Sample records for composting process temperature
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NASA Astrophysics Data System (ADS)
Azura Zakarya, Irnis; Baya Khalib, Siti Noor; Ramzi, Norhasykin Mohd
2018-03-01
Rice straw is considered as one of the most important agricultural residues and represented as one of the major by-products from rice production process. Normally, rice straw that produced after harvesting season been directly burned on-farm. Conversion of rice straw into value added compost will improve the productivity of plant, reduction of pollution towards environment and reduction of local pollution due to open burning activity. The objective of this study was to evaluate the performance of composting rice straw ash (RSA) with food waste (FW) and effective microorganisms (EM) in term of the compost quality (pH, temperature, moisture content). RSA was prepared by burning the raw rice straw at three different temperature of 300°C, 400°C and 500°C for one hour. EM used during the composting process was prepared by mixing of brown sugar, `tempe' and water that can be used after one week of fermentation process. There are four treatments of RSA-compost; RSA (300°C), RSA (400°C), RSA (500°C) and control (raw rice straw) with the same amount of compost medium; 1kg black soil, 0.5kg RSA, 3L EM and 1kg FW. The composting process happens for 30 days. During the composting process, all the parameters of RSA-compost obtained in a range like; pH value 8-10, temperature 20-50°C and moisture content 40-60%. The result showed that all compost quality of rice straw ash compost obtained in an acceptable range for final compost to establish.
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Effects of composting process on the dissipation of extractable sulfonamides in swine manure.
Liu, Bei; Li, Yanxia; Zhang, Xuelian; Feng, Chenghong; Gao, Min; Shen, Qiu
2015-01-01
Effects of composting on the fate of sulfonamides (SAs) in the manure-straw mixture were explored through a simulation of aerobic composting process. Additionally, factors of temperature and coexistence of heavy metal Cu that might influence the removal efficiency were particularly investigated. As shown in the results, the extractable SAs dissipated rapidly during the composting process. The coexistence of Cu in the composting process might have delayed the decline of SAs, but the drugs could still be completely removed by the end of the composting. In contrast to the thermophilic aerobic composting, extractable SAs in air-temperature-placed mixture dissipated much slower and 1.12-1.56mg/kg could be detected after 35days of incubation. The results confirmed that temperature could influence the dissipation of SAs, which was identified as a more important factor than Cu-coexistence. Hence, thermophilic aerobic composting is an effective process to eliminate VAs before manure land application. Copyright © 2014 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Barrena, R.; Canovas, C.; Sanchez, A.
2006-07-01
A macroscopic non-steady state energy balance was developed and solved for a composting pile of source-selected organic fraction of municipal solid waste during the maturation stage (13,500 kg of compost). Simulated temperature profiles correlated well with temperature experimental data (ranging from 50 to 70 deg. C) obtained during the maturation process for more than 50 days at full scale. Thermal inertia effect usually found in composting plants and associated to the stockpiling of large composting masses could be predicted by means of this simplified energy balance, which takes into account terms of convective, conductive and radiation heat dissipation. Heat lossesmore » in a large composting mass are not significant due to the similar temperatures found at the surroundings and at the surface of the pile (ranging from 15 to 40 deg. C). In contrast, thermophilic temperature in the core of the pile was maintained during the whole maturation process. Heat generation was estimated with the static respiration index, a parameter that is typically used to monitor the biological activity and stability of composting processes. In this study, the static respiration index is presented as a parameter to estimate the metabolic heat that can be generated according to the biodegradable organic matter content of a compost sample, which can be useful in predicting the temperature of the composting process.« less
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NASA Astrophysics Data System (ADS)
Oshima, Tairo; Moriya, Toshiyuki; Yoshii, Takahiro
The author and his colleagues have proposed the use of high temperature composting in space inhabitation. Composting has many advantages over burning in organic waste treatments. Composting is self-heating processes and needs no extra fuel. Composting requires no sophis-ticated equipment such as an incinerator. Composting emits no hazardous gases such as NOx, SOx and dioxines which are often produced by burning. The final product can be used as fer-tilizer in space farm land; resources recycling society can be constructed in space stations and space cities. In addition to these advantages, composting and compost soil may contribute to the environmental cleanup. During composting processes, harmful compounds to agricultural plants and animals can be destroyed. Seeds of weeds can be killed by high heat. Likewise pathogenic microbes in the waste can be eliminated during fermentation inside the composts. Recently we measured the survivability of E. coli in compost. E. coli was used as the represen-tative of the Gram-negative bacteria. Since many pathogenic strains belong to Gram-negative bacteria and Gram-negative bacteria are more resistant to antibiotics than gram-positive bac-teria. When E. coli cells were mixed in the compost pile of which inside temperature reaches up to 75oC, they died within a short period as expected. However, E. coli DNA was detected even after a day in high temperature compost. RNA has a shorter life-span than DNA, but was detected after incubation in compost for several hours. In addition to sterilizing effects due to high temperature, we found our compost soil has E. coli killing activity. When mixed with the compost soil at room temperature, E. coli died gradually. Extract of the compost soil also killed E. coli at room temperature, but it took a few days to eliminate E. coli completely. During the killing process, total number of living bacteria did not change, indicating that the killing activity is limited to some specific microorganisms. These findings suggest that the compost can be used to eliminate some of deleterious microbes from the environment without damages to the beneficial microbes. We are planning to test the killing activity of the com-post soil against more dangerous microorganisms such as Salmonella species, especially those pathogenic to barn animals.
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Bioremediation of diesel oil-contaminated soil by composting with biowaste.
Van Gestel, Kristin; Mergaert, Joris; Swings, Jean; Coosemans, Jozef; Ryckeboer, Jaak
2003-01-01
Soil spiked with diesel oil was mixed with biowaste (vegetable, fruit and garden waste) at a 1:10 ratio (fresh weight) and composted in a monitored composting bin system for 12 weeks. Pure biowaste was composted in parallel. In order to discern the temperature effect from the additional biowaste effect on diesel degradation, one recipient with contaminated soil was hold at room temperature, while another was kept at the actual composting temperature. Measurements of composting parameters together with enumerations and identifications of microorganisms demonstrate that the addition of the contaminated soil had a minor impact on the composting process. The first-order rate constant of diesel degradation in the biowaste mixture was four times higher than in the soil at room temperature, and 1.2 times higher than in the soil at composting temperature.
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Hanajima, Dai
2014-10-01
To elucidate the characteristics of ear corn residue as a bulking agent, the composting process using this residue was compared with processes using three other conventional materials such as sawdust, wheat straw and rice husk, employing a bench-scale composting reactor. As evaluated via biochemical oxygen demand (BOD), ear corn residue contains 3.3 and 2.0 times more easily digestible materials than sawdust and rice husk, respectively. In addition, mixing ear corn residue with manure resulted in reduced bulk density, which was the same as that of wheat straw and was 0.58 and 0.67 times lower than that of sawdust and a rice husk mixture, respectively. To evaluate temperature generation during the composting process, the maximum temperature and area under the temperature curve (AUCTEMP) were compared among the mixed composts of four bulking agents. Maximum temperature (54.3°C) as well as AUCTEMP (7310°C●h) of ear corn residue were significantly higher than those of sawdust and rice husk (P<0.05), and they are similar to that of wheat straw mixed compost. Along with the value of AUCTEMP, the highest organic matter losses of 31.1% were observed in ear corn residue mixed compost, followed by wheat straw, saw dust and rice husk. © 2014 Japanese Society of Animal Science.
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Co-composting of biowaste and wood ash, influence on a microbially driven-process.
Fernández-Delgado Juárez, Marina; Prähauser, Barbara; Walter, Andreas; Insam, Heribert; Franke-Whittle, Ingrid H
2015-12-01
A trial at semi-industrial scale was conducted to evaluate the effect of wood ash amendment on communal biowaste in a composting process and on the final composts produced. For this purpose, three treatments including an unamended control (C0) and composts with additions of 6% (C6), and 12% (C12) of wood ash (w/w) were studied, and physico-chemical parameters as well as microbial activity and community composition were investigated. At the end of the process, composts were tested for toxicity and quality, and microbial physiological activity. The influence of ash addition on compost temperature, pH, microbial activity and composition was stronger during the early composting stages and diminished with time, whereby composts became more similar. Using the COMPOCHIP microarray, a reduction in the pathogenic genera Listeria and Clostridium was observed, which together with the temperature increases of the composting process helped in the hygienisation of composts. Lactobacillus species were also affected, such that reduced hybridisation signals were observed with increased ash addition, due to the increased pH values in amended composts. Organic matter mineralisation was also increased through ash addition, and no negative effects on the composting process were observed. The nutrient content of the final products was increased through the addition of ash, and no toxic effects were observed. Nonetheless, greater concentrations of heavy metals were found in composts amended with more ash, which resulted in a downgrading of the compost quality according to the Austrian Compost Ordinance. Thus, regulation of both input materials and end-product quality is essential in optimising composting processes. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Ceustermans, A; De Clercq, D; Aertsen, A; Michiels, C; Geeraerd, A; Van Impe, J; Coosemans, J; Ryckeboer, J
2007-07-01
Determination of the minimum requirements (time-temperature relationship and moisture content) that are needed for a sufficient eradication of an indicator organism. To determine the hygienic safety of composting processes, the indicator organism Salmonella enterica ssp. enterica serotype Senftenberg strain W 775 (further abbreviated as W 775) was artificially inoculated on a meat carrier and monitored subsequently. Different types of composting processes, e.g. composting in enclosed facilities, in open-air and in-vessel composting, were investigated. The waste feedstocks used in this work were either biowastes (i.e. vegetable, fruit and garden wastes; also called source-separated household wastes) or pure garden wastes. Beside these large-scale trials, we also conducted some lab experiments in order to determine the impact of temperature, moisture content and the presence of an indigenous microflora on the eradication of W 775. We found the temperature to be the most important parameter to eradicate W 775 from compost. When the temperature of the compost heap is 60 degrees C and the moisture content varies between 60-65%, W 775 (10(8) CFU g(-1)) will be inactivated within 10 h of composting. The moisture content is, beside temperature, a second parameter that influences the survival of W 775. When the water content of the composting materials or meat carriers is reduced, a higher survival rate of W 775 was observed (survival rate increases 0.5 log(10) unit when there is a reduction of 5% in moisture content). In addition, other parameters (such as microbial antagonism, toxic compounds, etc.) have an influence on the survival of W 775 as well. Our study demonstrates that all types of composting processes tested in this work were sufficient to eradicate W 775 providing that they are well managed in terms of temperature and moisture content. To give a better view on the parameters of importance for the eradication of W 775 during composting.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kopčić, Nina, E-mail: nkopcic@fkit.hr; Vuković Domanovac, Marija; Kučić, Dajana
Highlights: • Apple and tobacco waste mixture was efficiently composted during 22 days. • Physical–chemical and microbiological properties of the mixture were suitable the process. • Evaluation of selected mathematical model showed good prediction of the temperature. • The temperature curve was a “mirror image” of the oxygen concentration curve. • The peak values of the temperature were occurred 9.5 h after the peak oxygen consumption. - Abstract: Efficient composting process requires set of adequate parameters among which physical–chemical properties of the composting substrate play the key-role. Combining different types of biodegradable solid waste it is possible to obtain amore » substrate eligible to microorganisms in the composting process. In this work the composting of apple and tobacco solid waste mixture (1:7, dry weight) was explored. The aim of the work was to investigate an efficiency of biodegradation of the given mixture and to characterize incurred raw compost. Composting was conducted in 24 L thermally insulated column reactor at airflow rate of 1.1 L min{sup −1}. During 22 days several parameters were closely monitored: temperature and mass of the substrate, volatile solids content, C/N ratio and pH-value of the mixture and oxygen consumption. The composting of the apple and tobacco waste resulted with high degradation of the volatile solids (53.1%). During the experiment 1.76 kg of oxygen was consumed and the C/N ratio of the product was 11.6. The obtained temperature curve was almost a “mirror image” of the oxygen concentration curve while the peak values of the temperature were occurred 9.5 h after the peak oxygen consumption.« less
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Martens, Jürgen
2005-01-01
The hygienic performance of biowaste composting plants to ensure the quality of compost is of high importance. Existing compost quality assurance systems reflect this importance through intensive testing of hygienic parameters. In many countries, compost quality assurance systems are under construction and it is necessary to check and to optimize the methods to state the hygienic performance of composting plants. A set of indicator methods to evaluate the hygienic performance of normal operating biowaste composting plants was developed. The indicator methods were developed by investigating temperature measurements from indirect process tests from 23 composting plants belonging to 11 design types of the Hygiene Design Type Testing System of the German Compost Quality Association (BGK e.V.). The presented indicator methods are the grade of hygienization, the basic curve shape, and the hygienic risk area. The temperature courses of single plants are not distributed normally, but they were grouped by cluster analysis in normal distributed subgroups. That was a precondition to develop the mentioned indicator methods. For each plant the grade of hygienization was calculated through transformation into the standard normal distribution. It shows the part in percent of the entire data set which meet the legal temperature requirements. The hygienization grade differs widely within the design types and falls below 50% for about one fourth of the plants. The subgroups are divided visually into basic curve shapes which stand for different process courses. For each plant the composition of the entire data set out of the various basic curve shapes can be used as an indicator for the basic process conditions. Some basic curve shapes indicate abnormal process courses which can be emended through process optimization. A hygienic risk area concept using the 90% range of variation of the normal temperature courses was introduced. Comparing the design type range of variation with the legal temperature defaults showed hygienic risk areas over the temperature courses which could be minimized through process optimization. The hygienic risk area of four design types shows a suboptimal hygienic performance.
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Germer, Jörn; Boh, Michael Yongha; Schoeffler, Marie; Amoah, Philip
2010-02-01
Small scale co-composting of faecal matter from dry toilet systems with shredded plant material and food waste was investigated in respect to heat development and deactivation of faecal indicators under tropical semiarid conditions. Open (uncovered) co-composting of faecal matter with shredded plant material alone did not generate temperatures high enough (<55 degrees C) to reduce the indicators sufficiently. The addition of food waste and confinement in chambers, built of concrete bricks and wooden boards, improved the composting process significantly. Under these conditions peak temperatures of up to 70 degrees C were achieved and temperatures above 55 degrees C were maintained over 2 weeks. This temperature and time is sufficient to comply with international composting regulations. The reduction of Escherichia coli, Enterococcus faecalis and Salmonella senftenberg in test containment systems placed in the core of the compost piles was very efficient, exceeding 5log10-units in all cases, but recolonisation from the cooler outer layers appeared to interfere with the sanitisation efficiency of the substrate itself. The addition of a stabilisation period by extending the composting process to over 4 months ensured that the load of E. coli was reduced to less than 10(3)cfu(-g) and salmonella were undetectable.
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Co-composting of palm oil mill sludge-sawdust.
Yaser, Abu Zahrim; Abd Rahman, Rakmi; Kalil, Mohd Sahaid
2007-12-15
Composting of Palm Oil Mill Sludge (POMS) with sawdust was conducted in natural aerated reactor. Composting using natural aerated reactor is cheap and simple. The goal of this study is to observe the potential of composting process and utilizing compost as media for growing Cymbopogun citratus, one of Malaysia herbal plant. The highest maximum temperature achieved is about 40 degrees C and to increase temperature bed, more biodegradable substrate needs to be added. The pH value decrease along the process with final pH compost is acidic (pH 5.7). The highest maximum organic losses are about 50% with final C/N ratio of the compost is about 19. Final compost also showed some fertilizing value but need to be adjusted to obtain an ideal substrate. Addition of about 70% sandy soil causes highest yield and excellent root development for C. citratus in potted media. Beside that, compost from POMS-sawdust also found to have fertilizer value and easy to handle. Composting of POMS with sawdust shows potential as an alternative treatment to dispose and recycle waste components.
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[Co-composting of high moisture vegetable waste, flower waste and chicken litter in pilot scale].
Zhang, Xiangfeng; Wang, Hongtao; Nie, Yongfeng; Qiu, Xiangyang
2003-03-01
Co-composting of different mixture made of vegetable waste, flower waste and chicken litter were studied. The first stage of composting was aerobic static bed based temperature feedback and control via aeration rate regulation. The second stage was window composting. At first stage, the pile was insulated and temperatures of at least 55 degrees C were maintained for a minimum of 3 days. The highest temperature was up to 73.3 degrees C. This is enough to kill pathogens. Moisture of pile decreased from 75% to 56% and organic matter was degraded from 65% to 50% during composting. The value of pH was stable at 8. Analysis of maturity and nutrition of compost showed that end-products of composting ware bio-stable and had abundant nutrition. This shows that co-composting of vegetable waste, flower waste and chicken litter can get high quality compost by optimizing composting process during 45 days. Composting can decrease nonpoint resource of organic solid waste by recycling nutrition to soil and improve fertility of soil.
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Arrigoni, Juan Pablo; Paladino, Gabriela; Garibaldi, Lucas Alejandro; Laos, Francisca
2018-06-01
Decentralized composting has been proposed as a best available practice, with a highly positive impact on municipal solid wastes management plans. However, in cold climates, decentralized small-scale composting performance to reach thermophilic temperatures (required for the product sanitization) could be poor, due to a lack of critical mass to retain heat. In addition, in these systems the composting process is usually disturbed when new portions of fresh organic waste are combined with previous batches. This causes modifications in the well-known composting evolution pattern. The objective of this work was to improve the understanding of these technical aspects through a real-scale decentralized composting experience carried out under cold climate conditions, in order to assess sanitization performance and to study the effects of fresh feedstock additions in the process evolution. Kitchen and garden organic wastes were composted in 500 L-static compost bins (without turning) for 244 days under cold climate conditions (Bariloche, NW Patagonia, Argentina), using pine wood shavings in a ratio of 1.5:1 v: v (waste: bulking agent). Temperature profile, stability indicators (microbial activity, carbon and nitrogen contents and ratio) and other variables (pH and electrical conductivity), were monitored throughout the experience. Our results indicate that small-scale composting (average generation rate of 7 kg d -1 ) is viable under cold weather conditions, since thermophilic sanitization temperatures (> 55 °C) were maintained for 3 consecutive days in most of the composting mass, according to available USEPA regulations commonly used as a reference for pathogens control in sewage sludge. On the other hand, stability indicators showed a differentiated organic matter degradation process along the compost bins height. Particularly, in the bottommost composting mix layer the process took a longer period to achieve compost stability than the upper layers, suggesting that differential organic matter transformation appears not to be necessarily associated to the order of the waste batches incorporation in a time line, as it could be expected. These findings suggest the need to discuss new ways of studying the composting process in small-scale compost bins as well as their commercial design. Copyright © 2018 Elsevier Ltd. All rights reserved.
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[Co-composting of high-moisture vegetable waste and flower waste in a batch operation].
Zhang, Xiangfeng; Wang, Hongtao; Nie, Yongfeng
2003-09-01
Co-composting of different mixture made of vegetable waste and flower waste were studied. The first stage of composting was aerobic static bed based temperature feedback in a batch operation and control via aeration rate regulation. The second stage was window composting. The total composting period was 45 days. About the station of half of celery and half of carnation, the pile was insulated and temperatures of at least 55 degrees C were maintained for about 11 days. The highest temperature was up to 65 degrees C. This is enough to kill pathogens. Moisture of pile decreased from 64.2% to 46.3% and organic matter was degraded from 74.7% to 55.6% during composting. The value of pH was had stable at 7. Analysis of maturity and nutrition of compost show that end-products of composting were bio-stable and had abundant nutrition. This shows that co-composting of vegetable waste and flower waste can get high quality compost by optimizing composting process during 45 days. Composting can decrease non-point resource of organic solid waste by recycling nutrition to soil and improve fertility of soil.
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In-Vessel Composting of Simulated Long-Term Missions Space-Related Solid Wastes
NASA Technical Reports Server (NTRS)
Rodriguez-Carias, Abner A.; Sager, John; Krumins, Valdis; Strayer, Richard; Hummerick, Mary; Roberts, Michael S.
2002-01-01
Reduction and stabilization of solid wastes generated during space missions is a major concern for the Advanced Life Support - Resource Recovery program at the NASA, Kennedy Space Center. Solid wastes provide substrates for pathogen proliferation, produce strong odor, and increase storage requirements during space missions. A five periods experiment was conducted to evaluate the Space Operation Bioconverter (SOB), an in vessel composting system, as a biological processing technology to reduce and stabilize simulated long-term missions space related solid-wastes (SRSW). For all periods, SRSW were sorted into components with fast (FBD) and slow (SBD) biodegradability. Uneaten food and plastic were used as a major FBD and SBD components, respectively. Compost temperature (C), CO2 production (%), mass reduction (%), and final pH were utilized as criteria to determine compost quality. In period 1, SOB was loaded with a 55% FBD: 45% SBD mixture and was allowed to compost for 7 days. An eleven day second composting period was conducted loading the SOB with 45% pre-composted SRSW and 55% FBD. Period 3 and 4 evaluated the use of styrofoam as a bulking agent and the substitution of regular by degradable plastic on the composting characteristics of SRSW, respectively. The use of ceramic as a bulking agent and the relationship between initial FBD mass and heat production was investigated in period 5. Composting SRSW resulted in an acidic fermentation with a minor increase in compost temperature, low CO2 production, and slightly mass reduction. Addition of styrofoam as a bulking agent and substitution of regular by biodegradable plastic improved the composting characteristics of SRSW, as evidenced by higher pH, CO2 production, compost temperature and mass reduction. Ceramic as a bulking agent and increase the initial FBD mass (4.4 kg) did not improve the composting process. In summary, the SOB is a potential biological technology for reduction and stabilization of mission space-related solid wastes. However, the success of the composting process may depend of the physical characteristics (particle size, porosity, structure, texture) of the SBD components which would require pre-processing of solid wastes before placing them in the SOB.
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Effects of air flow directions on composting process temperature profile
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kulcu, Recep; Yaldiz, Osman
2008-07-01
In this study, chicken manure mixed with carnation wastes was composted by using three different air flow directions: R1-sucking (downward), R2-blowing (upward) and R3-mixed. The aim was to find out the most appropriate air flow direction type for composting to provide more homogenous temperature distribution in the reactors. The efficiency of each aeration method was evaluated by monitoring the evolution of parameters such as temperature, moisture content, CO{sub 2} and O{sub 2} ratio in the material and dry material losses. Aeration of the reactors was managed by radial fans. The results showed that R3 resulted in a more homogenous temperaturemore » distribution and high dry material loss throughout the composting process. The most heterogeneous temperature distribution and the lowest dry material loss were obtained in R2.« less
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Utilization of solar energy in sewage sludge composting: fertilizer effect and application.
Chen, Yiqun; Yu, Fang; Liang, Shengwen; Wang, Zongping; Liu, Zizheng; Xiong, Ya
2014-11-01
Three reactors, ordinary, greenhouse, and solar, were constructed and tested to compare their impacts on the composting of municipal sewage sludge. Greenhouse and solar reactors were designed to evaluate the use of solar energy in sludge composting, including their effects on temperature and compost quality. After 40 days of composting, it was found that the solar reactor could provide more stable heat for the composting process. The average temperature of the solar reactor was higher than that of the other two systems, and only the solar reactor could maintain the temperature above 55°C for more than 3 days. Composting with the solar reactor resulted in 31.3% decrease in the total organic carbon, increased the germination index to 91%, decreased the total nitrogen loss, and produced a good effect on pot experiments. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Characterization and open windrow composting of MSW in Jodhpur City, Rajasthan, India.
Ambade, Bhushan; Sharma, Sunil; Sharma, Yukti; Sharma, Yagya
2013-07-01
Solid waste is sometimes not suitable for direct land application. Processing solid waste through composting converts it to a humus-containing organic material advantageous for agriculture/horticulture use. Major advantages of composting are stabilization of the wastes; substantially reduced C/N ratio and gas formation, and virtually elimination of odors and pathogens. Composting is accomplished under aerobic conditions developing temperatures of 55 degrees C or above. The windrow technique is simple and accomplished easily with standard equipments. The open windrow composting of municipal solid waste (MSW) in windrows was analyzed in this study for six weeks. The raw MSW was introduced to active composting without any source segregations. The moisture content of the MSW dropped from 58.88% to 48.06% and windrow attained a thermophillic temperature for about two weeks. It was observed that the pH, C/N ratio and temperature variations were comparable to that of traditional windrow composting. The peak temperature recorded was 68 degrees C and temperature remained above 60 degrees C for more than three weeks. The volume reduction was obtained by using one-cu.m. cage. The results indicate that the bulk composting could reduce by about 29% the total mass of the waste.
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Chroni, Christina; Kyriacou, Adamadini; Manios, Thrassyvoulos; Lasaridi, Konstantia-Ekaterini
2009-08-01
In a bid to identify suitable microbial indicators of compost stability, the process evolution during windrow composting of poultry manure (PM), green waste (GW) and biowaste was studied. Treatments were monitored with regard to abiotic factors, respiration activity (determined using the SOUR test) and functional microflora. The composting process went through typical changes in temperature, moisture content and microbial properties, despite the inherent feedstock differences. Nitrobacter and pathogen indicators varied as a monotonous function of processing time. Some microbial groups have shown a potential to serve as fingerprints of the different process stages, but still they should be examined in context with respirometric tests and abiotic parameters. Respiration activity reflected well the process stage, verifying the value of respirometric tests to access compost stability. SOUR values below 1 mg O(2)/g VS/h were achieved for the PM and the GW compost.
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Composting rice straw with sewage sludge and compost effects on the soil-plant system.
Roca-Pérez, L; Martínez, C; Marcilla, P; Boluda, R
2009-05-01
Composting organic residue is an interesting alternative to recycling waste as the compost obtained may be used as organic fertilizer. This study aims to assess the composting process of rice straw and sewage sludge on a pilot-scale, to evaluate both the quality of the composts obtained and the effects of applying such compost on soil properties and plant development in pot experiments. Two piles, with shredded and non-shredded rice straw, were composted as static piles with passive aeration. Throughout the composting process, a number of parameters were determined, e.g. colour, temperature, moisture, pH, electrical conductivity, organic matter, C/N ratio, humification index, cation exchange capacity, chemical oxygen demand, and germination index. Moreover, sandy and clayey soils were amended with different doses of mature compost and strewed with barley in pot experiments. The results show that compost made from shredded rice straw reached the temperatures required to maximise product sanitisation, and that the parameters indicating compost maturity were all positive; however, the humification index and NH(4) content were more selective. Therefore, using compost-amended soils at a dose of 34 Mg ha(-1) for sandy soil, and of 11 Mg ha(-1) for clayey soil improves soil properties and the growth of Hordeum vulgare plants. Under there conditions, the only limiting factor of agronomic compost utilisation was the increased soil salinity.
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Evaluation of laboratory-scale in-vessel co-composting of tobacco and apple waste.
Kopčić, Nina; Vuković Domanovac, Marija; Kučić, Dajana; Briški, Felicita
2014-02-01
Efficient composting process requires set of adequate parameters among which physical-chemical properties of the composting substrate play the key-role. Combining different types of biodegradable solid waste it is possible to obtain a substrate eligible to microorganisms in the composting process. In this work the composting of apple and tobacco solid waste mixture (1:7, dry weight) was explored. The aim of the work was to investigate an efficiency of biodegradation of the given mixture and to characterize incurred raw compost. Composting was conducted in 24 L thermally insulated column reactor at airflow rate of 1.1 L min(-1). During 22 days several parameters were closely monitored: temperature and mass of the substrate, volatile solids content, C/N ratio and pH-value of the mixture and oxygen consumption. The composting of the apple and tobacco waste resulted with high degradation of the volatile solids (53.1%). During the experiment 1.76 kg of oxygen was consumed and the C/N ratio of the product was 11.6. The obtained temperature curve was almost a "mirror image" of the oxygen concentration curve while the peak values of the temperature were occurred 9.5h after the peak oxygen consumption. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Cáceres, Rafaela; Coromina, Narcís; Malińska, Krystyna; Marfà, Oriol
2015-03-01
This study aimed to monitor process parameters when two by-products (green waste - GW, and the solid fraction of cattle slurry - SFCS) were composted to obtain growing media. Using compost in growing medium mixtures involves prolonged composting processes that can last at least half a year. It is therefore crucial to study the parameters that affect compost stability as measured in the field in order to shorten the composting process at composting facilities. Two mixtures were prepared: GW25 (25% GW and 75% SFCS, v/v) and GW75 (75% GW and 25% SFCS, v/v). The different raw mixtures resulted in the production of two different growing media, and the evolution of process management parameters was different. A new parameter has been proposed to deal with attaining the thermophilic temperature range and maintaining it during composting, not only it would be useful to optimize composting processes, but also to assess the hygienization degree. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Utilization of solar energy in sewage sludge composting: Fertilizer effect and application
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yiqun; Yu, Fang; Liang, Shengwen
2014-11-15
Highlights: • Solar energy technologies were utilized in aerobic sewage sludge composting. • Greenhouse and solar reactors were constructed to compare impacts on the composting. • Impatiens balsamina was planted in pot experiments to evaluate fertilizer effect. - Abstract: Three reactors, ordinary, greenhouse, and solar, were constructed and tested to compare their impacts on the composting of municipal sewage sludge. Greenhouse and solar reactors were designed to evaluate the use of solar energy in sludge composting, including their effects on temperature and compost quality. After 40 days of composting, it was found that the solar reactor could provide more stablemore » heat for the composting process. The average temperature of the solar reactor was higher than that of the other two systems, and only the solar reactor could maintain the temperature above 55 °C for more than 3 days. Composting with the solar reactor resulted in 31.3% decrease in the total organic carbon, increased the germination index to 91%, decreased the total nitrogen loss, and produced a good effect on pot experiments.« less
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Singh, R; Kim, J; Jiang, X
2012-05-01
The purpose of this study was to determine the effect of moisture on thermal inactivation of Salmonella spp. in poultry litter under optimal composting conditions. Thermal inactivation of Salmonella was studied in fresh poultry compost by simulating early phase of composting process. A mixture of three Salmonella serotypes grown in Tryptic soy broth with rifampin (TSB-R) was inoculated in fresh compost with 40 or 50% moisture at a final concentration of c. 7 log CFU g(-1). The inoculated compost was kept in an environmental chamber which was programmed to rise from room temperature to target composting temperatures in 2 days. In poultry compost with optimal moisture content (50%), Salmonella spp. survived for 96, 72 and 24 h at 50, 55 and 60°C, respectively, as compared with 264, 144 and 72 h at 50, 55 and 60°C, respectively, in compost with suboptimal moisture (40%). Pathogen decline was faster during the come-up time owing to higher ammonia volatilization. Our results demonstrated that Salmonella spp. survived longer in fresh poultry compost with suboptimal moisture of 40% than in compost with optimal moisture of 50% during thermophilic composting. High nitrogen content of the poultry compost is an additional factor contributing to Salmonella inactivation through ammonia volatilization during thermal exposure. This research validated the effectiveness of the current composting guidelines on Salmonella inactivation in fresh poultry compost. Both initial moisture level and ammonia volatilization are important factors affecting microbiological safety and quality of compost product. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.
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Nakasaki, Kiyohiko; Hirai, Hidehira
2017-07-01
The effects of inoculating the mesophilic yeast Pichia kudriavzevii RB1, which is able to degrade organic acids, on organic matter degradation in composting were elucidated. When model food waste with high carbohydrate content (C/N=22.3) was used, fluctuation in the inoculated yeast cell density was observed, as well as fluctuation in the composting temperature until day 5 when the temperature rose to 60°C, which is lethal for the yeast. After the decrease in yeast, acetic acid accumulated to levels as high as 20mg/g-ds in the composting material and vigorous organic matter degradation was inhibited. However, by maintaining the temperature at 40°C for 2days during the heating phase in the early stage of composting, both the organic acids originally contained in the raw material and acetic acid produced during the heating phase were degraded by the yeast. The concentration of acetic acid was kept at a relatively low level (10.1mg/g-ds at the highest), thereby promoting the degradation of organic matter by other microorganisms and accelerating the composting process. These results indicate that temperature control enhances the effects of microbial inoculation into composts. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Variation in microbial population during composting of agro-industrial waste.
Coelho, Luísa; Reis, Mário; Dionísio, Lídia
2013-05-01
Two compost piles were prepared, using two ventilation systems: forced ventilation and ventilation through mechanical turning. The material to compost was a mixture of orange waste, olive pomace, and grass clippings (2:1:1 v/v). During the composting period (375 days), samples were periodically taken from both piles, and the enumeration of fungi, actinomycetes, and heterotrophic bacteria was carried out. All studied microorganisms were incubated at 25 and 55 °C after inoculation in appropriate growth media. Fungi were dominant in the early stages of both composting processes; heterotrophic bacteria proliferated mainly during the thermophilic stage, and actinomycetes were more abundant in the final stage of the composting process. Our results showed that the physical and chemical parameters: temperature, pH, moisture, and aeration influenced the variation of the microbial population along the composting process. This study demonstrated that composting of these types of wastes, despite the prolonged mesophilic stage, provided an expected microbial variation.
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Indigenous microorganisms production and the effect on composting process
NASA Astrophysics Data System (ADS)
Abu-Bakar, Nurul-Ain; Ibrahim, Nazlina
2013-11-01
In this study, production of indigenous microorganisms (IMO) and effect on addition of IMO in composting process were done. Production of IMO was done in a series of steps to allow propagation of beneficial microorganisms. Effect of IMO addition in composting process was investigated by having 4 treatments; 1) rice straw without IMO nor manure and rice bran, 2) rice straw with IMO only, 3) rice straw with manure and rice bran, 4) rice straw with IMO, manure and rice bran. Production of IMO using cooked rice yields white molds. Addition of IMO during composting did not affect temperature increment. However, there were differences in numbers of microorganisms found during each stages of composting. Initial composting stage was dominated by mesophilic bacteria and actinomycetes, followed by thermophilic bacteria and later by actinomycetes upon composting completion. In conclusion, this study showed that IMO addition in composting increased microorganisms which are responsible in organic decomposition.
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Biochar for composting improvement and contaminants reduction. A review.
Godlewska, Paulina; Schmidt, Hans Peter; Ok, Yong Sik; Oleszczuk, Patryk
2017-12-01
Biochar is characterised by a large specific surface area, porosity, and a large amount of functional groups. All of those features cause that biochar can be a potentially good material in the optimisation of the process of composting and final compost quality. The objective of this study was to compile the current knowledge on the possibility of biochar application in the process of composting and on the effect of biochar on compost properties and on the content of contaminants in compost. The paper presents the effect of biochar on compost maturity indices, composting temperature and moisture, and also on the content and bioavailability of nutrients and of organic and inorganic contaminants. In the paper note is also taken of the effect of biochar added to composted material on plants, microorganisms and soil invertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Composting in small laboratory pilots: performance and reproducibility.
Lashermes, G; Barriuso, E; Le Villio-Poitrenaud, M; Houot, S
2012-02-01
Small-scale reactors (<10 l) have been employed in composting research, but few attempts have assessed the performance of composting considering the transformations of organic matter. Moreover, composting at small scales is often performed by imposing a fixed temperature, thus creating artificial conditions, and the reproducibility of composting has rarely been reported. The objectives of this study are to design an innovative small-scale composting device safeguarding self-heating to drive the composting process and to assess the performance and reproducibility of composting in small-scale pilots. The experimental setup included six 4-l reactors used for composting a mixture of sewage sludge and green wastes. The performance of the process was assessed by monitoring the temperature, O(2) consumption and CO(2) emissions, and characterising the biochemical evolution of organic matter. A good reproducibility was found for the six replicates with coefficients of variation for all parameters generally lower than 19%. An intense self-heating ensured the existence of a spontaneous thermophilic phase in all reactors. The average loss of total organic matter (TOM) was 46% of the initial content. Compared to the initial mixture, the hot water soluble fraction decreased by 62%, the hemicellulose-like fraction by 68%, the cellulose-like fraction by 50% and the lignin-like fractions by 12% in the final compost. The TOM losses, compost stabilisation and evolution of the biochemical fractions were similar to observed in large reactors or on-site experiments, excluding the lignin degradation, which was less important than in full-scale systems. The reproducibility of the process and the quality of the final compost make it possible to propose the use of this experimental device for research requiring a mass reduction of the initial composted waste mixtures. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Changes in the microbial communities during co-composting of digestates☆
Franke-Whittle, Ingrid H.; Confalonieri, Alberto; Insam, Heribert; Schlegelmilch, Mirko; Körner, Ina
2014-01-01
Anaerobic digestion is a waste treatment method which is of increasing interest worldwide. At the end of the process, a digestate remains, which can gain added value by being composted. A study was conducted in order to investigate microbial community dynamics during the composting process of a mixture of anaerobic digestate (derived from the anaerobic digestion of municipal food waste), green wastes and a screened compost (green waste/kitchen waste compost), using the COMPOCHIP microarray. The composting process showed a typical temperature development, and the highest degradation rates occurred during the first 14 days of composting, as seen from the elevated CO2 content in the exhaust air. With an exception of elevated nitrite and nitrate levels in the day 34 samples, physical–chemical parameters for all compost samples collected during the 63 day process indicated typical composting conditions. The microbial communities changed over the 63 days of composting. According to principal component analysis of the COMPOCHIP microarray results, compost samples from the start of the experiment were found to cluster most closely with the digestate and screened compost samples. The green waste samples were found to group separately. All starting materials investigated were found to yield fewer and lower signals when compared to the samples collected during the composting experiment. PMID:24456768
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Characterization of dairy cattle manure/wallboard paper compost mixture.
Saludes, Ronaldo B; Iwabuchi, Kazunori; Miyatake, Fumihito; Abe, Yoshiyuki; Honda, Yoshifumi
2008-10-01
The aim of this research was to evaluate the use of manufacturing wallboard paper scraps as an alternative bulking agent for dairy cattle manure composting. The characteristics of the composting process were studied based on the changes in physico-chemical parameters and final compost quality. Composting of dairy cattle manure with wallboard paper was performed in a 481-L cylindrical reactor with vacuum-type aeration. Rapid degradation of organic matter was observed during the thermophilic stage of composting due to high microbial activity. High temperature and alkaline pH conditions promoted intense ammonia emission during the early stage of composting. The number of mesophilic and thermophilic microorganisms were found to be affected by changes in temperature at different composting stages. The total nitrogen (N), phosphorus (P), potassium (K), and sodium (Na) concentrations of the mixture did not change significantly after 28days of composting. However, the presence of gypsum in the paper scraps increased the calcium content of the final compost. The wallboard paper had no phyto-inhibitory effects as shown by high germination index of final compost (GI=99%).
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Evaluation of an aerobic composting process for the management of Specified Risk Materials (SRM).
Zeng, J; Price, G W; Arnold, P
2012-06-15
In Nova Scotia (NS), approximately 2700 tonnes of Specified Risk Materials (SRM) are produced annually. SRM disposal is a serious concern for abattoirs and the beef industry. Composting offers a low risk and simple means to transform raw SRM into a more stable and easily managed material. In this project, wheat straw and sawdust were used to compost with SRM on a pilot scale. The study evaluated changes over time in total carbon, total nitrogen, pH, temperature, moisture content and electrical conductivity. Compost temperatures in all treatments met the Canadian Council of Ministers of the Environment (CCME) guidelines for pathogen kill. The compost maturity tests showed that the evolution of CO(2)-C in all the final compost products was less than 1 mg g(-1) organic matter day(-1). Wheat straw performed well as a composting feedstock for raw SRM as sawdust. While the wheat straw has advantages including greater availability, lower cost and easily decomposable carbon compounds more management is required to maintain adequate compost temperatures. The influences of seasonal variations due to temperate climatic conditions on SRM composting were also studied with wheat straw. The results suggest no significant differences in composting effectiveness between the two seasons. Copyright © 2012 Elsevier B.V. All rights reserved.
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Spatial variability of heating profiles in windrowed poultry litter
USDA-ARS?s Scientific Manuscript database
In-house windrow composting of broiler litter has been suggested as a means to reduce microbial populations between flocks. Published time-temperature goals are used to determine the success of the composting process for microbial reductions. Spatial and temporal density of temperature measurement ...
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USDA-ARS?s Scientific Manuscript database
Composting is a complex process to produce fertilizers used to improve crop yields. A complete composting process usually confers bactericidal effect due to change of temperature and pH However, some produce outbreaks associated with Shiga toxin-producing E. coli (STEC) contamination were linked to ...
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Changes in the microbial communities during co-composting of digestates.
Franke-Whittle, Ingrid H; Confalonieri, Alberto; Insam, Heribert; Schlegelmilch, Mirko; Körner, Ina
2014-03-01
Anaerobic digestion is a waste treatment method which is of increasing interest worldwide. At the end of the process, a digestate remains, which can gain added value by being composted. A study was conducted in order to investigate microbial community dynamics during the composting process of a mixture of anaerobic digestate (derived from the anaerobic digestion of municipal food waste), green wastes and a screened compost (green waste/kitchen waste compost), using the COMPOCHIP microarray. The composting process showed a typical temperature development, and the highest degradation rates occurred during the first 14 days of composting, as seen from the elevated CO2 content in the exhaust air. With an exception of elevated nitrite and nitrate levels in the day 34 samples, physical-chemical parameters for all compost samples collected during the 63 day process indicated typical composting conditions. The microbial communities changed over the 63 days of composting. According to principal component analysis of the COMPOCHIP microarray results, compost samples from the start of the experiment were found to cluster most closely with the digestate and screened compost samples. The green waste samples were found to group separately. All starting materials investigated were found to yield fewer and lower signals when compared to the samples collected during the composting experiment. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Wang, Lin; Mao, Jiugeng; Zhao, Hejuan; Li, Min; Wei, Qishun; Zhou, Ying; Shao, Heping
2016-09-01
Rice straw (RS) is an important raw material for the preparation of Agaricus bisporus compost in China. In this study, the characterization of composting process from RS and wheat straw (WS) was compared for mushroom production. The results showed that the temperature in RS compost increased rapidly compared with WS compost, and the carbon (C)/nitrogen (N) ratio decreased quickly. The microbial changes during the Phase I and Phase II composting process were monitored using denaturing gradient gel electrophoresis (DGGE) and phospholipid fatty acid (PLFA) analysis. Bacteria were the dominant species during the process of composting and the bacterial community structure dramatically changed during heap composting according to the DGGE results. The bacterial community diversity of RS compost was abundant compared with WS compost at stages 4-5, but no distinct difference was observed after the controlled tunnel Phase II process. The total amount of PLFAs of RS compost, as an indicator of microbial biomass, was higher than that of WS. Clustering by DGGE and principal component analysis of the PLFA compositions revealed that there were differences in both the microbial population and community structure between RS- and WS-based composts. Our data indicated that composting of RS resulted in improved degradation and assimilation of breakdown products by A. bisporus, and suggested that the RS compost was effective for sustaining A. bisporus mushroom growth as well as conventional WS compost.
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Singh, Randhir; Kim, Jinkyung; Shepherd, Marion W; Luo, Feng; Jiang, Xiuping
2011-06-01
A three-strain mixture of Escherichia coli O157:H7 was inoculated into fresh dairy compost (ca. 10(7) CFU/g) with 40 or 50% moisture and was placed in an environmental chamber (ca. 70% humidity) that was programmed to ramp from room temperature to selected composting temperatures in 2 and 5 days to simulate the early composting phase. The surviving E. coli O157:H7 population was analyzed by direct plating and enrichment. Optimal and suboptimal compost mixes, with carbon/nitrogen (C/N) ratios of 25:1 and 16:1, respectively, were compared in this study. In the optimal compost mix, E. coli O157:H7 survived for 72, 48, and 24 h in compost with 40% moisture and for 72, 24, and 24 h with 50% moisture at 50, 55, and 60°C, respectively, following 2 days of come-up time (rate of heating up). However, in the suboptimal compost mix, the pathogen survived for 288, 72, and 48 h in compost with 40% moisture and for 240, 72, 24 h in compost with 50% moisture at the same temperatures, respectively. Pathogen survival was longer, with 5 days of come-up time compared with 2 days of come-up. Overall, E. coli O157:H7 was inactivated faster in the compost with 50% moisture than in the compost with 40% at 55 and 60°C. Both moisture and come-up time were significant factors affecting Weibull model parameters. Our results suggest that slow come-up time at the beginning of composting can extend pathogen survival during composting. Additionally, both the C/N ratio and the initial moisture level in the compost mix affect the rate of pathogen inactivation as well.
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Singh, Randhir; Kim, Jinkyung; Shepherd, Marion W.; Luo, Feng; Jiang, Xiuping
2011-01-01
A three-strain mixture of Escherichia coli O157:H7 was inoculated into fresh dairy compost (ca. 107 CFU/g) with 40 or 50% moisture and was placed in an environmental chamber (ca. 70% humidity) that was programmed to ramp from room temperature to selected composting temperatures in 2 and 5 days to simulate the early composting phase. The surviving E. coli O157:H7 population was analyzed by direct plating and enrichment. Optimal and suboptimal compost mixes, with carbon/nitrogen (C/N) ratios of 25:1 and 16:1, respectively, were compared in this study. In the optimal compost mix, E. coli O157:H7 survived for 72, 48, and 24 h in compost with 40% moisture and for 72, 24, and 24 h with 50% moisture at 50, 55, and 60°C, respectively, following 2 days of come-up time (rate of heating up). However, in the suboptimal compost mix, the pathogen survived for 288, 72, and 48 h in compost with 40% moisture and for 240, 72, 24 h in compost with 50% moisture at the same temperatures, respectively. Pathogen survival was longer, with 5 days of come-up time compared with 2 days of come-up. Overall, E. coli O157:H7 was inactivated faster in the compost with 50% moisture than in the compost with 40% at 55 and 60°C. Both moisture and come-up time were significant factors affecting Weibull model parameters. Our results suggest that slow come-up time at the beginning of composting can extend pathogen survival during composting. Additionally, both the C/N ratio and the initial moisture level in the compost mix affect the rate of pathogen inactivation as well. PMID:21498743
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He, Xueqin; Han, Lujia; Ge, Jinyi; Huang, Guangqun
2018-04-01
This study establishes an optimal mathematical modelling to rationally describe the dynamic changes and spatial distribution of temperature and oxygen concentration in the aerobic composting process using coupling mass-heat-momentum transfer based on the microbial mechanism. Two different conditional composting experiments, namely continuous aeration and intermittent aeration, were performed to verify the proposed model. The results show that the model accurately predicted the dynamic changes in temperature (case I: R 2 = 0.93, RMSE = 1.95 K; case II: R 2 = 0.86, RMSE = 4.69 K) and oxygen concentration (case I: R 2 = 0.90, RMSE = 1.26%; case II: R 2 = 0.75, RMSE = 2.93%) in the central point of compost substrates. It also systematically simulated fluctuations in oxygen concentration caused by boundary conditions and the spatial distribution of the actual temperature and oxygen concentration. The proposed model exhibits good applicability in simulating the actual working conditions of aerobic composting process. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Zhang, Lu; Sun, Xiangyang
2016-02-01
A recyclable organic bulking agent (BA) that can be screened and was developed to optimize green waste (GW) composting. This study investigated the use of wood chips (WC) (at 0%, 15%, and 25%) and/or composted green waste (CGW) (at 0%, 25%, and 35%) as the BAs in the two-stage composting of GW. The combined addition of WC and CGW improved the conditions of composting process and the quality of compost product in terms of composting temperature, porosity, water retention, particle-size distribution, pH, electrical conductivity (EC), cation exchange capacity (CEC), nitrogen losses, humification indices, microbial numbers, enzyme activities, macro- and micro-nutrient contents, and toxicity to germinating seeds. The compost matured in only 22days with the optimized two-stage composting method rather than in the 90-270days typically required for traditional composting. The optimal two-stage composting process and the best quality of compost product were obtained with the combined addition of 15% WC and 35% CGW. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Jain, Mayur Shirish; Jambhulkar, Rohit; Kalamdhad, Ajay S
2018-04-01
Composting is an efficient technology to reduce pathogenic bodies and stabilize the organic matter in organic wastes. This research work investigates an effect of biochar as amendment to improve the composting efficiency and its effect on degradation kinetics, physical and nutritional properties. Biochar (2.5, 5 and 10% (w/w)) were added into a mixture of Hydrilla verticillata, cow dung and sawdust having ratio of 8:1:1 (control), respectively. Biochar addition resulted in advanced thermophilic temperatures (59 °C) and could improve the physical properties of composting process. Owing to addition of 5% biochar as a bulking agent in composting mixture, the final product from composting, total nitrogen increased by 45% compared to the other trials, and air-filled porosity decreased by 39% and was found to be within recommended range from literature studies. Considering temperature, degradation rate and nitrogen transformation the amendment of 5% biochar is recommended for Hydrilla verticillata composting. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Makan, Abdelhadi; Assobhei, Omar; Mountadar, Mohammed
2013-01-03
This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts.For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times.This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications.
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Berendes, David; Levy, Karen; Knee, Jackie; Handzel, Thomas; Hill, Vincent R
2015-01-01
The goal of this study was to evaluate the microbial die-off in a latrine waste composting system in Port-au-Prince, Haiti. Temperature data and samples were collected from compost aged 0-12+ months. Samples collected from compost bin centers and corners at two depths were assessed for moisture content, E. coli concentration, and Ascaris spp. viability. Center temperatures in compost bins were all above 58 °C, while corner temperatures were 10 - 20 °C lower. Moisture content was 67 ± 10% in all except the oldest compost. A 4-log reduction in E. coli was observed over the first sixteen weeks of composting at both locations and depths, after which E. coli was undetectable (LOD: 142 MPN g(-1) dry weight). In new compost, 10.4% and 8.3% of Ascaris eggs were viable and fully embryonated, respectively. Percent viability dropped to zero in samples older than six weeks. These findings indicate that the Haitian EcoSan composting process was effective in inactivating E. coli and Ascaris spp. in latrine waste within sixteen weeks. This study is one of the first to document efficacy of an ecological sanitation system under field conditions and provides insight into composting methods and monitoring for other international settings.
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Moore, John E; Watabe, Miyuki; Stewart, Andrew; Cherie Millar, B; Rao, Juluri R
2009-01-01
Maturing compost heaps normally attaining temperatures ranging from 55 to 65 degrees C is generally regarded to conform to recommended biological risks and sanitation standards for composts stipulated by either EU or US-EPA. Composted products derived from animal sources are further required by EU biohazard safety regulatory legislation that such composts either attain 70 degrees C for over 3h during maturation or via treatment at 70 degrees C for 1h before being considered for dispensation on land. The setting of the upper limit of thermal lethality at 70 degrees C/1h for achieving biosecurity of the animal waste composted products (e.g. pelleted fertilizer formulations) is not properly substantiated by specific validation tests, comprising a 'wipe-out' step (usually via autoclaving) followed by inoculation of a prescribed bacterium, exposure to 70 degrees C/1h and the lethality determined. Pelleted formulations of composts are not amenable for wet methods (autoclaving) for wipe-out sterilization step as this is detrimental to the pellet and compromises sample integrity. This study describes a laboratory method involving the employment of ((60)Co) irradiation 'wipe-out' step to: (a) compost sub-samples drawn from compost formulation heaps and (b) pelleted products derived from composted animal products while determining the thermal lethality of a given time/temperature (70 degrees C/1h) treatment process and by challenging the irradiated sample (not just with one bacterium but), out with 10 potential food-poisoning organisms from the bacterial genera (Campylobacter, Escherichia, Listeria, Salmonella, Yersinia) frequently detected in pig and poultry farm wastes. This challenge test on compost sub-samples can be a useful intervention ploy for 'inspection and validation' technique for composters during the compost maturity process, whose attainment of temperatures of 55-65 degrees C is presumed sufficient for attainment of sanitation. Stringent measures are further required by law for composted products arising from rural industrialists producing pelleted fertilizers from re-composted animal agriculture wastes comprising pig slurry solids, poultry litter and spent mushroom compost, which carry residual food-borne pathogens with implications to the food chain including humans. Environmentally, sustainable means of recycling farm wastes require that final composted products are free of pathogens in compliance with environmental safety legislation before their release to the market. This test developed provides a science-based risk characterization tool for sustainably managing environmental safety by 'validating' thermal lethality of a given composting process or their derivatives achieved without compromising the sample integrity or ambiguity attached to microbiological validation involving steam sterilization or autoclaving procedures and helps audit the resurgent bacterial populations from surviving non-pathogenic organisms in the end-products of animal waste compost formulations.
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Darimani, Hamidatu S; Ito, Ryusei; Maiga, Ynoussa; Sou, Mariam; Funamizu, Naoyuki; Maiga, Amadou H
2016-01-01
Safe and appropriate disposal of human waste is a basic requirement for sanitation and protection of public health. For proper sanitation and nutrient recovery, it is necessary to ensure effective treatment methods to complete pathogen destruction in excreta prior to reuse. Composting toilets convert faeces to a reusable resource such as fertilizer or humus for organic agriculture. A composting toilet for rural Burkina Faso was created by modifying a commercial model available in Japan to improve hygiene and increase food production. The toilet has shown to result in a degraded final product, but its effectiveness for pathogen destruction was unclear due to low temperatures generated from the toilet. This study aimed to sanitize compost withdrawn from the composting toilet for food production by setting post-treatment conditions. The inactivation kinetics of Ascaris suum eggs, selected as an indicator for helminth eggs, was determined during post-treatment at different temperatures (30°C, 40°C, 50°C and 60°C) with varying moisture contents (MC) (50%, 60% and 70%). The treatment of compost in a possible additional post-treatment after the composting process was tried in the laboratory test. Inactivation of A. suum eggs was fast with greater than two log reductions achieved within 2 h for temperature 50°C and 50% MC and greater than three log reductions for temperature 60°C and 50% MC within 3 h. Statistical analysis showed the significant impact of temperature and moisture on the inactivation rates of A. suum eggs. The post-treatment can efficiently increase helminth eggs destruction prior to reuse.
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Laos, F; Semenas, L; Labud, V
2004-07-26
The composting process is used to treat biosolids from the Wastewater Treatment Plant of Bariloche (NW Patagonia, Argentina). Since 1998, an odourless, innocuous and stable organic amendment has been produced at the Biosolids Composting Plant of Bariloche. However, volatile compounds produced during this process, attract different vectors, mainly insects belonging to the Order Diptera, particularly in summer. To evaluate factors associated with the attraction of Diptera to composting windrows, volatile compounds, wind velocity, ambient and windrow temperatures were measured and their relationships with the taxa of flies found were determined. Sampling was conducted several months on newly formed windrows during 3 weeks of the thermophilic composting period. Composite samples from each windrow were taken on the first day of each sampling week, from November 1999 to March 2000 to analyze volatile compounds using an 'electronic nose'. Windrow and ambient temperatures and wind velocity were recorded on three consecutive days of each week, from January to March 2000; also the capture of flies was performed in this period. A weekly mean value was calculated for each environmental variable. Canonical Correspondence Analysis was employed to determine relationships between taxa of flies and the studied factors. The electronic nose discriminated among odours emitted, differentiating windrows by the bulking agent employed and by week of the thermophilic composting period. Ambient temperatures increased slightly during the sampling weeks; the highest values of wind velocity were registered during the second sampling week while windrow temperatures were sustained approximately 60 degrees C. Canonical Correspondence Analysis showed that attraction of flies to composting windrows was related to minimum and maximum ambient temperatures and volatile compounds for Muscina stabulans, Fannia sp. and Acaliptratae and to wind velocity for Ophyra sp., Sarcophaga sp., Cochliomyia macellaria and Phaenicia sericata. Copyright 2004 Elsevier B.V.
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Milczarek, M; Neczaj, E; Parkitna, K
2013-01-01
The purpose of this work is to study the characteristics of the co-composting of municipal solid waste (MSW), sewage sludge, grass and sawdust. Differing proportions of biodegradable waste were investigated through changes of temperature, oxygen consumption, organic matters, moisture content, carbon, nitrogen, C/N ratio as well as heavy metals and pathogen microorganisms content. The present study has shown that addition of MSW above 10% had a negative impact on the composting process. The initial C/N of the mixtures with a higher MSW content was below 18. Lower losses of organic matter occurred during composting for the mixture with the highest addition of MSW. Although studies have shown that composting is a good method for the disposal of organic waste additional research is required in order to optimize the organic and nitrogen compounds degradation during the co-composting process. In conclusion, a 1:4:4:1 mixture of MSW:sewage sludge:grass:sawdust is recommended because it can achieve high temperature as well as the highest organic matter degradation and highest N content in the final composting product. The concentration of heavy and light metals in all composts was within the limits of regulation of the Polish Minister of Agriculture and Rural Development.
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Intelligent composting assisted by a wireless sensing network.
López, Marga; Martinez-Farre, Xavier; Casas, Oscar; Quilez, Marcos; Polo, Jose; Lopez, Oscar; Hornero, Gemma; Pinilla, Mirta R; Rovira, Carlos; Ramos, Pedro M; Borges, Beatriz; Marques, Hugo; Girão, Pedro Silva
2014-04-01
Monitoring of the moisture and temperature of composting process is a key factor to obtain a quality product beyond the quality of raw materials. Current methodologies for monitoring these two parameters are time consuming for workers, sometimes not sufficiently reliable to help decision-making and thus are ignored in some cases. This article describes an advance on monitoring of composting process through a Wireless Sensor Network (WSN) that allows measurement of temperature and moisture in real time in multiple points of the composting material, the Compo-ball system. To implement such measurement capabilities on-line, a WSN composed of multiple sensor nodes was designed and implemented to provide the staff with an efficient monitoring composting management tool. After framing the problem, the objectives and characteristics of the WSN are briefly discussed and a short description of the hardware and software of the network's components are presented. Presentation and discussion of practical issues and results obtained with the WSN during a demonstration stage that took place in several composting sites concludes the paper. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Chen, Zhiqiang; Wang, Yao; Wen, Qinxue; Zhang, Shihua; Yang, Lian
2016-09-01
Composting is a potential alternative for cephalosporin C fermentation dregs (CCFDs) compared with incineration process or landfill because of its advantage of recovering nutrients. In this research, CCFDs and activated sludge (AS) were co-composted to analyze the feasibility of recycling the nutrients in CCFDs. A pilot-scale aerobic composting system with an auto-control system was used in this research, and the maturity and security of the compost product were evaluated. The temperature of the composting mixtures was maintained above 55°C for more than 3 days during the composting, indicating that co-composting of CCFDs and AS could reach the compost maturity standard, and the seeds germination index (GI) increased from 17.61% to 68.93% by the end of the composting process (28 days). However, the degradation rate of cephalosporin C (CPC) was only 6.58% during the composting process. Monitoring the quality of antibiotic resistance genes (ARGs) in the composts showed that the log copy of blaTEM in the composts increased from 2.15 in the initial phase to 6.37 after 28 days. Long-term investigation of CPC degradation and ARGs variation was conducted for the composts; CPC could still be detected after the maturity phases. A removal efficiency of 49.10% could be achieved in 110 days, while the log copy of ARGs increased to 7.93. Although a higher GI value (>80.00%) was observed, the risk of recycling the CCFDs compost product into land is still high.
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Composting technology in waste stabilization: On the methods, challenges and future prospects.
Onwosi, Chukwudi O; Igbokwe, Victor C; Odimba, Joyce N; Eke, Ifeanyichukwu E; Nwankwoala, Mary O; Iroh, Ikemdinachi N; Ezeogu, Lewis I
2017-04-01
Composting technology has become invaluable in stabilization of municipal waste due to its environmental compatibility. In this review, different types of composting methods reportedly applied in waste management were explored. Further to that, the major factors such as temperature, pH, C/N ratio, moisture, particle size that have been considered relevant in the monitoring of the composting process were elucidated. Relevant strategies to improve and optimize process effectiveness were also addressed. However, during composting, some challenges such as leachate generation, gas emission and lack of uniformity in assessing maturity indices are imminent. Here in, these challenges were properly addressed and some strategies towards ameliorating them were proffered. Finally, we highlighted some recent technologies that could improve composting. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Composting on Mars or the Moon: I. Comparative evaluation of process design alternatives
NASA Technical Reports Server (NTRS)
Finstein, M. S.; Strom, P. F.; Hogan, J. A.; Cowan, R. M.; Janes, H. W. (Principal Investigator)
1999-01-01
As a candidate technology for treating solid wastes and recovering resources in bioregenerative Advanced Life Support, composting potentially offers such advantages as compactness, low mass, near ambient reactor temperatures and pressures, reliability, flexibility, simplicity, and forgiveness of operational error or neglect. Importantly, the interactions among the physical, chemical, and biological factors that govern composting system behavior are well understood. This article comparatively evaluates five Generic Systems that describe the basic alternatives to composting facility design and control. These are: 1) passive aeration; 2) passive aeration abetted by mechanical agitation; 3) forced aeration--O2 feedback control; 4) forced aeration--temperature feedback control; 5) forced aeration--integrated O2 and temperature feedback control. Each of the five has a distinctive pattern of behavior and process performance characteristics. Only Systems 4 and 5 are judged to be viable candidates for ALS on alien worlds, though which is better suited in this application is yet to be determined.
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Fernández-Delgado Juárez, M; Gómez-Brandón, M; Insam, H
2015-04-01
A trial was carried out to evaluate the influence of wood ash admixture on biowaste composting. The aim was to find the optimal dosage of ash addition to enhance the composting process without endangering the final compost characteristics and use. Six treatments including an unamended control (K0) and composts with additions of 3% (K3), 6% (K6), 9% (K9), 12% (K12) and 15% (K15) of wood ash (w/w) were studied. The composting process was monitored in situ for 49days, by measuring temperature, CO2, O2, and CH4 in the piles and pH, electric conductivity (EC), and inorganic N in the laboratory. At the end of the process, the products were tested for Reifegrad (maturity), toxicity and quality. The addition of up to 15% of wood ash to biowaste did not negatively affect the composting process, and the initial differences found between both the low and high ash-treated composts were attenuated with the ongoing process development. Nevertheless, and mainly due to Cd level, composts with higher ash amendment did not comply with the highest quality standards established by the Austrian Compost Ordinance. The failure of obtaining class A+ quality after ash amendment emphasizes the need for a rigid quality selection of (bottom) ashes and thus reducing environmental risks related to high pollutant loads originating from the ashes. Copyright © 2014 Elsevier B.V. All rights reserved.
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Bari, Quazi H; Koenig, Albert
2012-11-01
The aeration rate is a key process control parameter in the forced aeration composting process because it greatly affects different physico-chemical parameters such as temperature and moisture content, and indirectly influences the biological degradation rate. In this study, the effect of a constant airflow rate on vertical temperature distribution and organic waste degradation in the composting mass is analyzed using a previously developed mathematical model of the composting process. The model was applied to analyze the effect of two different ambient conditions, namely, hot and cold ambient condition, and four different airflow rates such as 1.5, 3.0, 4.5, and 6.0 m(3) m(-2) h(-1), respectively, on the temperature distribution and organic waste degradation in a given waste mixture. The typical waste mixture had 59% moisture content and 96% volatile solids, however, the proportion could be varied as required. The results suggested that the model could be efficiently used to analyze composting under variable ambient and operating conditions. A lower airflow rate around 1.5-3.0 m(3) m(-2) h(-1) was found to be suitable for cold ambient condition while a higher airflow rate around 4.5-6.0 m(3) m(-2) h(-1) was preferable for hot ambient condition. The engineered way of application of this model is flexible which allows the changes in any input parameters within the realistic range. It can be widely used for conceptual process design, studies on the effect of ambient conditions, optimization studies in existing composting plants, and process control. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Effects of brown sugar and calcium superphosphate on the secondary fermentation of green waste.
Zhang, Lu; Sun, Xiangyang; Tian, Yun; Gong, Xiaoqiang
2013-03-01
The generation of green waste is increasing rapidly with population growth in China, and green waste is commonly treated by composting. The objective of this work was to study the physical and chemical characteristics of composted green waste as affected by a two-stage composting process and by the addition of brown sugar (at 0.0%, 0.5%, and 1%) and calcium superphosphate (Ca(H2PO4)2·H2O) (at 0%, 3%, and 6%) during the second stage. With or without these additives, all the composts displayed two peaks in fermentation temperature and matured in only 30days. Compared to traditional industrial composting, the composting method described here increased the duration of high-temperature fermentation period, reduced the maturity time, and reduced costs. Addition of 0.5% brown sugar plus 6% calcium superphosphate produced the highest quality compost with respect to C/N ratio, pH, organic matter content, electrical conductivity, particle-size distribution, and other characteristics. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Effects of biochar on nitrogen transformation and heavy metals in sludge composting.
Liu, Wei; Huo, Rong; Xu, Junxiang; Liang, Shuxuan; Li, Jijin; Zhao, Tongke; Wang, Shutao
2017-07-01
Composting is regarded as an effective treatment to suppress pathogenic organisms and stabilize the organic material in sewage sludge. This study investigated the use of biochar as an amendment to improve the composting effectiveness and reduce the bioavailability of heavy metals and loss of nitrogen during composting. Biochar of 0%, 1%, 3%, 5% and 7% were added into a mixture of sludge and straw, respectively. The use of biochar, even in small amounts, altered the composting process and the properties of the end products. Biochar addition resulted in a higher pile temperature (66°C) and could reduce nitrogen loss by transforming ammonium into nitrite. In the 5% biochar group, the final product from sludge composting, ammonia nitrogen, decreased by 22.4% compared to the control, and nitrate nitrogen increased by 310.6%. Considering temperature and N transformation, the treatment with 5% biochar is suggested for sludge composting. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Himanen, Marina; Hänninen, Kari
2011-02-01
In-vessel composting of three stocks with originally different degree of organic matter degradation was conducted for: (1) kitchen source-separated bio-waste (BW), (2) aerobic (AS) as well as (3) anaerobic sludges (AnS) from municipal wastewater treatment plant. Composting experiment lasted over a year. The highest activity of the process was in the BW compost. It was implied by the highest temperature, CO(2) release, ammonification and nitrification, intensive accumulation and removal of low-weight carboxylic acids (water- and NaOH-extractable). Between the sludges higher mineralization and CO2 release was in AnS, while ammonification and nitrification were higher in AS compost; no significant difference between sludge composts was noticed for dynamics of pH, conductivity, concentrations of LWCA, and some nutrient compounds and heavy metals. Nitrogen content of the final compost increased in BW, but decreased in AS and AnS. Phytotoxicity of Lepidium sativum was eliminated faster in sludge composts compared to BW compost. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Optimization of food waste compost with the use of biochar.
Waqas, M; Nizami, A S; Aburiazaiza, A S; Barakat, M A; Ismail, I M I; Rashid, M I
2018-06-15
This paper aims to examine the influence of biochar produced from lawn waste in accelerating the degradation and mineralization rates of food waste compost. Biochar produced at two different temperatures (350 and 450 °C) was applied at the rates 10 and 15% (w/w) of the total waste to an in-vessel compost bioreactor for evaluating its effects on food waste compost. The quality of compost was assessed against stabilization indices such as moisture contents (MC), electrical conductivity (EC), organic matters (OM) degradation, change in total carbon (TC) and mineral nitrogen contents such as ammonium (NH 4 + ) and nitrate (NO 3 - ). The use of biochar significantly improved the composting process and physiochemical properties of the final compost. Results showed that in comparison to control trial, biochar amended compost mixtures rapidly achieved the thermophilic temperature, increased the OM degradation by 14.4-15.3%, concentration of NH 4 + by 37.8-45.6% and NO 3 - by 50-62%. The most prominent effects in term of achieving rapid thermophilic temperature and a higher concentration of NH 4 + and NO 3 - were observed at 15% (w/w) biochar. According to compost quality standard of United States (US), California, Germany, and Austria, the compost stability as a result of biochar addition was achieved in 50-60 days. Nonetheless, the biochar produced at 450 °C had similar effects as to biochar produced at 350 °C for most of the compost parameters. Therefore, it is recommended to produce biochar at 350 °C to reduce the energy requirements for resource recovery of biomass and should be added at a concentration of 15% (w/w) to the compost bioreactor for achieving a stable compost. Copyright © 2017 Elsevier Ltd. All rights reserved.
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2013-01-01
This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts. For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times. This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications. PMID:23369502
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Composting of rice straw with effective microorganisms (EM) and its influence on compost quality.
Jusoh, Mohd Lokman Che; Manaf, Latifah Abd; Latiff, Puziah Abdul
2013-02-07
This study aims to assess the effect of EM application on the composting process of rice straw with goat manure and green waste and to evaluate the quality of both compost treatments. There are two treatment piles in this study, in which one pile was applied with EM and another pile without EM. Each treatment was replicated three times with 90 days of composting duration. The parameters for the temperature, pH, TOC and C/N ratio, show that decomposition of organic matter occurs during the 90-day period. The t-test conducted shows that there is a significant difference between compost with EM and compost without EM. The application of EM in compost increases the macro and micronutrient content. The following parameters support this conclusion: compost applied with EM has more N, P and K content (P < 0.05) compared to compost without EM. Although the Fe in compost with EM is much higher (P < 0.05) than in the compost without EM, for Zn and Cu, there is no significant difference between treatments. This study suggests that the application of EM is suitable to increase the mineralization in the composting process. The final resultant compost indicated that it was in the range of the matured level and can be used without any restriction.
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Respiration and enzymatic activities as indicators of stabilization of sewage sludge composting.
Nikaeen, Mahnaz; Nafez, Amir Hossein; Bina, Bijan; Nabavi, BiBi Fatemeh; Hassanzadeh, Akbar
2015-05-01
The objective of this work was to study the evolution of physico-chemical and microbial parameters in the composting process of sewage sludge (SS) with pruning wastes (PW) in order to compare these parameters with respect to their applicability in the evaluation of organic matter (OM) stabilization. To evaluate the composting process and organic matter stability, different microbial activities were compared during composting of anaerobically digested SS with two volumetric ratios, 1:1 and 3:1 of PW:SS and two aeration techniques including aerated static piles (ASP) and turned windrows (TW). Dehydrogenase activity, fluorescein diacetate hydrolysis, and specific oxygen uptake rate (SOUR) were used as microbial activity indices. These indices were compared with traditional parameters, including temperature, pH, moisture content, organic matter, and C/N ratio. The results showed that the TW method and 3:1 (PW:SS) proportion was superior to the ASP method and 1:1 proportion, since the former accelerate the composting process by catalyzing the OM stabilization. Enzymatic activities and SOUR, which reflect microbial activity, correlated well with temperature fluctuations. Based on these results it appears that SOUR and the enzymatic activities are useful parameters to monitor the stabilization of SS compost. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Qian, Xiaoyong; Shen, Genxiang; Wang, Zhenqi; Guo, Chunxia; Liu, Yangqing; Lei, Zhongfang; Zhang, Zhenya
2014-02-01
Composting is considered to be a primary treatment method for livestock manure and rice straw, and high degree of maturity is a prerequisite for safe land application of the composting products. In this study pilot-scale experiments were carried out to characterize the co-composting process of livestock manure with rice straw, as well as to establish a maturity evaluation index system for the composts obtained. Two pilot composting piles with different feedstocks were conducted for 3 months: (1) swine manure and rice straw (SM-RS); and (2) dairy manure and rice straw (DM-RS). During the composting process, parameters including temperature, moisture, pH, total organic carbon (TOC), organic matter (OM), different forms of nitrogen (total, ammonia and nitrate), and humification index (humic acid and fulvic acid) were monitored in addition to germination index (GI), plant growth index (PGI) and Solvita maturity index. OM loss followed the first-order kinetic model in both piles, and a slightly faster OM mineralization was achieved in the SM-RS pile. Also, the SM-RS pile exhibited slightly better performance than the DM-RS according to the evolutions of temperature, OM degradation, GI and PGI. The C/N ratio, GI and PGI could be included in the maturity evaluation index system in which GI>120% and PGI>1.00 signal mature co-composts. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Influence of compost covers on the efficiency of biowaste composting process.
Marešová, Karolina; Kollárová, Mária
2010-12-01
The temperature of matured compost is an indicator of feedstock quality and also a good feedback informing about the suitability of an applied technological procedure. Two independent experiments using the technology of windrow composting at open area were conducted with the final goal to evaluate the effect of compost pile covering (in comparison with uncovered piles) on the course of composting process - behaviour of temperature over time and oxygen content. Two types of sheets were used - Top Tex permeable sheet and impermeable polyethylene sheet. The experiment I (summer months) aimed at comparison of efficiency between the Top Tex sheet cover and the uncovered compost piles, while experiment II (autumn months) compared treatments using the Top Tex sheet and polyethylene sheet by contrast. Within the experiment I the composts consisted of cattle slurry and fresh grass matter at a ratio of 1:1, in case of experiment II consisted of pig/cattle manure, fresh grass matter and chipped material at a ratio of about 1:2:1. The obtained data showed no significant differences among the cover treatments according to ANOVA. The only exception was oxygen content in pile 4 (experiment II) under Top Tex sheet, where a markedly higher oxygen content than under polyethylene sheet was measured during the whole composting period. It was the only case where statistical analysis proved a significant difference; the p-value was 0.0002. Copyright © 2010. Published by Elsevier Ltd.
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Zafar, Urooj; Houlden, Ashley; Robson, Geoffrey D
2013-12-01
Plastics play an essential role in the modern world due to their low cost and durability. However, accumulation of plastic waste in the environment causes wide-scale pollution with long-lasting effects, making plastic waste management expensive and problematic. Polyurethanes (PUs) are heteropolymers that made up ca. 7% of the total plastic production in Europe in 2011. Polyester PUs in particular have been extensively reported as susceptible to microbial biodegradation in the environment, particularly by fungi. In this study, we investigated the impact of composting on PUs, as composting is a microbially rich process that is increasingly being used for the processing of green waste and food waste as an economically viable alternative to landfill disposal. PU coupons were incubated for 12 weeks in fresh compost at 25°C, 45°C, and 50°C to emulate the thermophilic and maturation stages of the composting process. Incubation at all temperatures caused significant physical deterioration of the polyester PU coupons and was associated with extensive fungal colonization. Terminal restriction fragment length polymorphism (TRFLP) analysis and pyrosequencing of the fungal communities on the PU surface and in the surrounding compost revealed that the population on the surface of PU was different from the surrounding compost community, suggesting enrichment and selection. The most dominant fungi identified from the surfaces of PU coupons by pyrosequencing was Fusarium solani at 25°C, while at both 45°C and 50°C, Candida ethanolica was the dominant species. The results of this preliminary study suggest that the composting process has the potential to biodegrade PU waste if optimized further in the future.
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Zafar, Urooj; Houlden, Ashley
2013-01-01
Plastics play an essential role in the modern world due to their low cost and durability. However, accumulation of plastic waste in the environment causes wide-scale pollution with long-lasting effects, making plastic waste management expensive and problematic. Polyurethanes (PUs) are heteropolymers that made up ca. 7% of the total plastic production in Europe in 2011. Polyester PUs in particular have been extensively reported as susceptible to microbial biodegradation in the environment, particularly by fungi. In this study, we investigated the impact of composting on PUs, as composting is a microbially rich process that is increasingly being used for the processing of green waste and food waste as an economically viable alternative to landfill disposal. PU coupons were incubated for 12 weeks in fresh compost at 25°C, 45°C, and 50°C to emulate the thermophilic and maturation stages of the composting process. Incubation at all temperatures caused significant physical deterioration of the polyester PU coupons and was associated with extensive fungal colonization. Terminal restriction fragment length polymorphism (TRFLP) analysis and pyrosequencing of the fungal communities on the PU surface and in the surrounding compost revealed that the population on the surface of PU was different from the surrounding compost community, suggesting enrichment and selection. The most dominant fungi identified from the surfaces of PU coupons by pyrosequencing was Fusarium solani at 25°C, while at both 45°C and 50°C, Candida ethanolica was the dominant species. The results of this preliminary study suggest that the composting process has the potential to biodegrade PU waste if optimized further in the future. PMID:24056469
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Composting toilets as a sustainable alternative to urban sanitation – A review
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anand, Chirjiv K., E-mail: chirjiv@gmail.com; Apul, Defne S., E-mail: defne.apul@utoledo.edu
2014-02-15
Highlights: • Composting toilets can be an alternative to flush based sanitation. • Many different composting toilet designs are available. • Composting is affected by moisture content, temperature, carbon to nitrogen ratio. • There are many barriers to composting toilets. • Research is needed in science based design of composting toilets. - Abstract: In today’s flush based urban sanitation systems, toilets are connected to both the centralized water and wastewater infrastructures. This approach is not a sustainable use of our water and energy resources. In addition, in the U.S., there is a shortfall in funding for maintenance and upgrade ofmore » the water and wastewater infrastructures. The goal of this paper was to review the current knowledge on composting toilets since this technology is decentralized, requires no water, creates a value product (fertilizer) and can possibly reduce the burden on the current infrastructure as a sustainable sanitation approach. We found a large variety of composting toilet designs and categorized the different types of toilets as being self contained or central; single or multi chamber; waterless or with water/foam flush, electric or non-electric, and no-mix or combined collection. Factors reported as affecting the composting process and their optimum values were identified as; aeration, moisture content (50–60%), temperature (40–65 °C), carbon to nitrogen ratio (25–35), pH (5.5–8.0), and porosity (35–50%). Mass and energy balance models have been created for the composting process. However there is a literature gap in the use of this knowledge in design and operation of composting toilets. To evaluate the stability and safety of compost for use as fertilizer, various methods are available and the temperature–time criterion approach is the most common one used. There are many barriers to the use of composting toilets in urban settings including public acceptance, regulations, and lack of knowledge and experience in composting toilet design and operation and program operation.« less
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Berry, Elaine D; Millner, Patricia D; Wells, James E; Kalchayanand, Norasak; Guerini, Michael N
2013-08-01
Reducing Escherichia coli O157:H7 in livestock manures before application to cropland is critical for reducing the risk of foodborne illness associated with produce. Our objective was to determine the fate of naturally occurring E. coli O157:H7 and other pathogens during minimally managed on-farm bovine manure composting processes. Feedlot pen samples were screened to identify E. coli O157:H7-positive manure. Using this manure, four piles of each of three different composting formats were constructed in each of two replicate trials. Composting formats were (i) turned piles of manure plus hay and straw, (ii) static stockpiles of manure, and (iii) static piles of covered manure plus hay and straw. Temperatures in the tops, toes, and centers of the conical piles (ca. 6.0 m(3) each) were monitored. Compost piles that were turned every 2 weeks achieved higher temperatures for longer periods in the tops and centers than did piles that were left static. E. coli O157:H7 was not recovered from top samples of turned piles of manure plus hay and straw at day 28 and beyond, but top samples from static piles were positive for the pathogen up to day 42 (static manure stockpiles) and day 56 (static covered piles of manure plus hay and straw). Salmonella, Campylobacter spp., and Listeria monocytogenes were not found in top or toe samples at the end of the composting period, but E. coli O157:H7 and Listeria spp. were recovered from toe samples at day 84. Our findings indicate that some minimally managed composting processes can reduce E. coli O157:H7 and other pathogens in bovine manure but may be affected by season and/or initial levels of indigenous thermophilic bacteria. Our results also highlight the importance of adequate C:N formulation of initial mixtures for the production of high temperatures and rapid composting, and the need for periodic turning of the piles to increase the likelihood that all parts of the mass are subjected to high temperatures.
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NASA Technical Reports Server (NTRS)
Finstein, M. S.; Hogan, J. A.; Sager, J. C.; Cowan, R. M.; Strom, P. F.; Janes, H. W. (Principal Investigator)
1999-01-01
Whereas Earth-based composting reactors that effectively control the process are batch operations with bottom-to-top airflow, in extraterrestrial application both the fresh waste and the air need to be introduced from above. Stabilized compost and used air would exit below. This materials flow pattern permits the addition of waste whenever generated, obviating the need for multiple reactors, and the incorporation of a commode in the lid. Top loading in turn dictates top-down aeration, so that the most actively decomposing material (greatest need for heat removal and O2 replenishment) is first encountered. This novel material and aeration pattern was tested in conjunction with temperature feedback process control. Reactor characteristics were: working, volume, 0.15 m3; charge, 2 kg dry biomass per day (comparable to a 3-4 person self-sufficient bioregenerative habitat); retention time, 7 days. Judging from temperature profile, O2 level, air usage, pressure head loss, moisture, and odor, the system was effectively controlled over a 35-day period. Dry matter disappearance averaged 25% (10-42%). The compost product was substantially, though not completely, stabilized. This demonstrates the compatibility of top-wise introduction of waste and air with temperature feedback process control.
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Finstein, M S; Hogan, J A; Sager, J C; Cowan, R M; Strom, P F
1999-01-01
Whereas Earth-based composting reactors that effectively control the process are batch operations with bottom-to-top airflow, in extraterrestrial application both the fresh waste and the air need to be introduced from above. Stabilized compost and used air would exit below. This materials flow pattern permits the addition of waste whenever generated, obviating the need for multiple reactors, and the incorporation of a commode in the lid. Top loading in turn dictates top-down aeration, so that the most actively decomposing material (greatest need for heat removal and O2 replenishment) is first encountered. This novel material and aeration pattern was tested in conjunction with temperature feedback process control. Reactor characteristics were: working, volume, 0.15 m3; charge, 2 kg dry biomass per day (comparable to a 3-4 person self-sufficient bioregenerative habitat); retention time, 7 days. Judging from temperature profile, O2 level, air usage, pressure head loss, moisture, and odor, the system was effectively controlled over a 35-day period. Dry matter disappearance averaged 25% (10-42%). The compost product was substantially, though not completely, stabilized. This demonstrates the compatibility of top-wise introduction of waste and air with temperature feedback process control.
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Zhou, Cheng; Liu, Zhang; Huang, Zhao-Lin; Dong, Ming; Yu, Xiao-Long; Ning, Ping
2015-06-01
In considering the impact of inoculation time and the characteristics of composting material and inoculants on the usefulness of inoculation, a new composting strategy has been proposed and studied, in which three inocula were inoculated at three stages of composting process respectively: inoculum A (Thermoactinomyces sp. GF1 and GF2) was inoculated before fermentation to increase or maintain high temperature of pile, inoculum B (Coprinus cinerea and Coprinus comatus) was inoculated after thermophilic phase to promote degradation of lignin, and inoculum C (Trichoderma harzianum and Rhizopus oryzae) was inoculated after 30-day fermentation to promote degradation of cellulose. The results showed that the inoculations could significantly enhance the temperature of pile and the degradation of lignocelluloses. When inocula A, B, and C were inoculated into pile, temperature increased from 25°C to 65°C, from 33°C to 39°C and from 33°C to 38°C respectively and 35% lignin and 43% cellulose had been degraded in inoculated pile compared to the degradation of 15% lignin and 25% cellulose in control pile. As a result, the C/N ratio dropped more rapidly degraded in the inoculated pile (reached 20 after 33-day fermentation) than that in the control pile (reached 21.7 after 45-day fermentation). In addition, the volume loss in inoculated pile (76.5%) was higher than that in control pile (53.2%). The study, therefore, indicated that inoculating proper microorganisms at appropriate time improved the composting process and our new composting strategy would be propitious to the co-composting dairy manure with rice straw. Copyright © 2015 Elsevier Ltd. All rights reserved.
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The fate of the recombinant DNA in corn during composting.
Guan, Jiewen; Spencer, J Lloyd; Ma, Bao-Luo
2005-01-01
In order to make regulations that safeguard food and the environment, an understanding of the fate oftransgenes from genetically modified (GM) plants is of crucial importance. A compost experiment including mature transgenic corn plants and seeds of event Bt 176 (Zea mays L.) was conducted to trace the fate of the transgene cryIA(b) during the period of composting. In bin 1, shredded corn plants including seeds were composted above a layer of cow manure and samples from the corn layer were collected at intervals during a 12-month period. The samples were tested for the transgene persistence and microbial counts and also the compost was monitored for temperature. In bin 2, piles of corn seeds, surrounded by sheep manure and straw, were composted for 12 months. A method combining nested polymerase chain reaction (PCR) and southern hybridization was developed for detection of the transgene in compost. The detection sensitivity was 200 copies of the transgene per gram of dry composted corn material. Composting commenced on day 0, and the transgene was detected in specimens from bin 1 on days 0 and 7 but not on day 14 or thereafter. The transgene in corn seeds was not detectable after 12 months of composting in bin 2. Temperatures in both bins rose to about 50 degrees C within 2 weeks and remained above that temperature for about 3 months, even when the ambient temperature dropped below -20 degrees C. Extracts from compost were inoculated onto culture plates and then were incubated at 23 to 55 degrees C. Within the first 2 weeks of composting in bin 1, the counts of bacteria incubated at 55 degrees C increased from 3.5 to 7.5 log10, whereas those incubated at 23 degrees C remained at about 7.5 log10. The counts of fungi incubated at 45 degrees C increased slightly from 2.5 to 3.1 log10, but those incubated at 23 degrees C decreased from 6.3 to 3.0 log10. The rapid degradation of the transgene during composting of Bt corn plants suggested that the composting process could be used for safe disposal of transgenic plant wastes.
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Effects of alkyl polyglycoside (APG) on composting of agricultural wastes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang Fabao; Gu Wenjie, E-mail: guwenjie1982@yahoo.cn; Xu Peizhi
2011-06-15
Composting is the biological degradation and transformation of organic materials under controlled conditions to promote aerobic decomposition. To find effective ways to accelerate composting and improve compost quality, numerous methods including additive addition, inoculation of microorganisms, and the use of biosurfactants have been explored. Studies have shown that biosurfactant addition provides more favorable conditions for microorganism growth, thereby accelerating the composting process. However, biosurfactants have limited applications because they are expensive and their use in composting and microbial fertilizers is prohibited. Meanwhile, alkyl polyglycoside (APG) is considered a 'green' surfactant. This study aims to determine whether APG addition into amore » compost reaction vessel during 28-day composting can enhance the organic matter degradation and composting process of dairy manure. Samples were periodically taken from different reactor depths at 0, 3, 5, 7, 14, 21, and 28 days. pH levels, electrical conductivity (EC), ammonium and nitrate nitrogen, seed germination indices, and microbial population were determined. Organic matter and total nitrogen were also measured. Compared with the untreated control, the sample with APG exhibited slightly increased microbial populations, such as bacteria, fungi, and actinomycetes. APG addition increased temperatures without substantially affecting compost pH and EC throughout the process. After 28 days, APG addition increased nitrate nitrogen concentrations, promoted matter degradation, and increased seed germination indices. The results of this study suggest that the addition of APG provides more favorable conditions for microorganism growth, slightly enhancing organic matter decomposition and accelerating the composting process, improving the compost quality to a certain extent.« less
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Effects of alkyl polyglycoside (APG) on composting of agricultural wastes.
Zhang, Fabao; Gu, Wenjie; Xu, Peizhi; Tang, Shuanhu; Xie, Kaizhi; Huang, Xu; Huang, Qiaoyi
2011-06-01
Composting is the biological degradation and transformation of organic materials under controlled conditions to promote aerobic decomposition. To find effective ways to accelerate composting and improve compost quality, numerous methods including additive addition, inoculation of microorganisms, and the use of biosurfactants have been explored. Studies have shown that biosurfactant addition provides more favorable conditions for microorganism growth, thereby accelerating the composting process. However, biosurfactants have limited applications because they are expensive and their use in composting and microbial fertilizers is prohibited. Meanwhile, alkyl polyglycoside (APG) is considered a "green" surfactant. This study aims to determine whether APG addition into a compost reaction vessel during 28-day composting can enhance the organic matter degradation and composting process of dairy manure. Samples were periodically taken from different reactor depths at 0, 3, 5, 7, 14, 21, and 28 days. pH levels, electrical conductivity (EC), ammonium and nitrate nitrogen, seed germination indices, and microbial population were determined. Organic matter and total nitrogen were also measured. Compared with the untreated control, the sample with APG exhibited slightly increased microbial populations, such as bacteria, fungi, and actinomycetes. APG addition increased temperatures without substantially affecting compost pH and EC throughout the process. After 28 days, APG addition increased nitrate nitrogen concentrations, promoted matter degradation, and increased seed germination indices. The results of this study suggest that the addition of APG provides more favorable conditions for microorganism growth, slightly enhancing organic matter decomposition and accelerating the composting process, improving the compost quality to a certain extent. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Assessment of compost maturity by using an electronic nose.
López, Rafael; Giráldez, Inmaculada; Palma, Alberto; Jesús Díaz, M
2016-02-01
The composting process produces and emits hundreds of different gases. Volatile organic compounds (VOCs) can provide information about progress of composting process. This paper is focused on the qualitative and quantitative relationships between compost age, as sign of compost maturity, electronic-nose (e-nose) patterns and composition of compost and composting gas at an industrial scale plant. Gas and compost samples were taken at different depths from composting windrows of different ages. Temperature, classical chemical parameters, O2, CO, combustible gases, VOCs and e-nose profiles were determined and related using principal component analysis (PCA). Factor analysis carried out to a data set including compost physical-chemical properties, pile pore gas composition and composting time led to few factors, each one grouping together standard composting parameters in an easy to understand way. PCA obtained from e-nose profiles allowed the classifying of piles, their aerobic-anaerobic condition, and a rough estimation of the composting time. That would allow for immediate and in-situ assessment of compost quality and maturity by using an on-line e-nose. The e-nose patterns required only 3-4 sensor signals to account for a great percentage (97-98%) of data variance. The achieved patterns both from compost (chemical analysis) and gas (e-nose analysis) samples are robust despite the high variability in feedstock characteristics (3 different materials), composting conditions and long composting time. GC-MS chromatograms supported the patterns. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Composting of rice straw with effective microorganisms (EM) and its influence on compost quality
2013-01-01
This study aims to assess the effect of EM application on the composting process of rice straw with goat manure and green waste and to evaluate the quality of both compost treatments. There are two treatment piles in this study, in which one pile was applied with EM and another pile without EM. Each treatment was replicated three times with 90 days of composting duration. The parameters for the temperature, pH, TOC and C/N ratio, show that decomposition of organic matter occurs during the 90-day period. The t-test conducted shows that there is a significant difference between compost with EM and compost without EM. The application of EM in compost increases the macro and micronutrient content. The following parameters support this conclusion: compost applied with EM has more N, P and K content (P < 0.05) compared to compost without EM. Although the Fe in compost with EM is much higher (P < 0.05) than in the compost without EM, for Zn and Cu, there is no significant difference between treatments. This study suggests that the application of EM is suitable to increase the mineralization in the composting process. The final resultant compost indicated that it was in the range of the matured level and can be used without any restriction. PMID:23390930
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Composting in small laboratory pilots: Performance and reproducibility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lashermes, G.; Barriuso, E.; Le Villio-Poitrenaud, M.
2012-02-15
Highlights: Black-Right-Pointing-Pointer We design an innovative small-scale composting device including six 4-l reactors. Black-Right-Pointing-Pointer We investigate the performance and reproducibility of composting on a small scale. Black-Right-Pointing-Pointer Thermophilic conditions are established by self-heating in all replicates. Black-Right-Pointing-Pointer Biochemical transformations, organic matter losses and stabilisation are realistic. Black-Right-Pointing-Pointer The organic matter evolution exhibits good reproducibility for all six replicates. - Abstract: Small-scale reactors (<10 l) have been employed in composting research, but few attempts have assessed the performance of composting considering the transformations of organic matter. Moreover, composting at small scales is often performed by imposing a fixed temperature, thus creatingmore » artificial conditions, and the reproducibility of composting has rarely been reported. The objectives of this study are to design an innovative small-scale composting device safeguarding self-heating to drive the composting process and to assess the performance and reproducibility of composting in small-scale pilots. The experimental setup included six 4-l reactors used for composting a mixture of sewage sludge and green wastes. The performance of the process was assessed by monitoring the temperature, O{sub 2} consumption and CO{sub 2} emissions, and characterising the biochemical evolution of organic matter. A good reproducibility was found for the six replicates with coefficients of variation for all parameters generally lower than 19%. An intense self-heating ensured the existence of a spontaneous thermophilic phase in all reactors. The average loss of total organic matter (TOM) was 46% of the initial content. Compared to the initial mixture, the hot water soluble fraction decreased by 62%, the hemicellulose-like fraction by 68%, the cellulose-like fraction by 50% and the lignin-like fractions by 12% in the final compost. The TOM losses, compost stabilisation and evolution of the biochemical fractions were similar to observed in large reactors or on-site experiments, excluding the lignin degradation, which was less important than in full-scale systems. The reproducibility of the process and the quality of the final compost make it possible to propose the use of this experimental device for research requiring a mass reduction of the initial composted waste mixtures.« less
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Study on rapid bio-drying technology of cow dung with CaO2
NASA Astrophysics Data System (ADS)
Chen, Xiaotian; Qu, Guangfei; Liu, Shugen; Xie, Ruosong; He, Yanhua
2017-05-01
Effect of CaO2 on cow dung rapid bio-drying technology was researched. A static aerobic composting system was applied to this experiment which combining natural ventilation with Turing in the process of composting. The physical characteristics of cow dung was observed and the compost temperature, moisture content, organic matter, total nitrogen, total phosphorus, potassium content was determined which in order to study the effect of CaO2 on rapid drying of cattle in the compost. In the initial stage of compost, adding CaO2 groups compared with the control group, the temperature rise faster, 4-6 days in advance to the thermophilic phase; at the end of composting, the CaO2 composition and moisture content decreased significantly to below 30%. The addition of CaO2 in fertilizer was shorten the composting time, extend the thermophilic phase, to provide sufficient oxygen meeting the growth needs of aerobic microorganisms. It convinced that the rapid bio-drying of dairy manure has a good effect and provided a new idea for the effective treatment of cow dung.
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Domestic sewage sludge composting in a rotary drum reactor: optimizing the thermophilic stage.
Rodríguez, Luis; Cerrillo, María I; García-Albiach, Valentín; Villaseñor, José
2012-12-15
The aim of this paper was to study the influence of four process variables (turning frequency, gas-phase oxygen level, type of bulking agent and sludge/bulking agent mixing ratio) on the performance of the sewage sludge composting process using a rotary drum pilot scale reactor, in order to optimize the thermophilic stage and reduce the processing time. Powdered sawdust, wood shavings, wood chips, prunings waste and straw were used as bulking agents and the thermophilic stage temperature profile was used as the main indicator for gauging if the composting process was developing correctly. Our results showed that a 12 h(-1) turning frequency and an oxygen concentration of 10% were the optimal conditions for the composting process to develop. The best results were obtained by mixing the sewage sludge with wood shavings in a 3:1 w/w ratio (on a wet basis), which adapted the initial moisture content and porosity to an optimal range and led to a maximum temperature of 70 °C being reached thus ensuring the complete removal of pathogens. Moisture, C:N ratio, pH, organic matter, heavy metals, pathogens and stability were all analysed for every mixture obtained at the end of the thermophilic stage. These parameters were compared with the limits established by the Spanish regulation on fertilizers (RD 824/2005) in order to assess if the compost obtained could be used on agricultural soils. The right combination of having optimal process variables combined with an appropriate reactor design allowed the thermophilic stage of the composting process to be speeded up, hence obtaining a compost product, after just two weeks of processing that (with the exception of the moisture content) complied with the Spanish legal requirements for fertilizers, without requiring a later maturation stage. Copyright © 2012 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, R.T.; Ziegenfuss, P.S.; Marks, P.J.
1989-03-01
A field-scale demonstration of composting propellants-contaminated sediment was conducted at the Badger Army Ammunition Plant (BAAP). Composting, as used at BAAP, is a treatment process in which organic-chemical contaminated soils or sediments are mixed with organic materials such as manure to enhance the role of microbial metabolism in degrading and stabilizing soil/sediment contaminants. Sediments contaminated with the propellant nitrocellulose (NC) were mixed with manure, alfalfa, livestock feed, and wood chips and composted in four static piles. Negative pressure aeration was used to maintain aerobiosis and remove excess heat. Experimental variables investigated during the study were temperature (mesophilic, 35 C vs.more » thermophilic, 55 C), sediment loading (19 to 32 weight percent), and NC loading. Small aliquots of compost (approximately 400 cu cm) were spiked with pure NC, placed in porous nylon bags and buried in compost piles. These bagged compost samples were used to determine if high levels of NC could be successfully composted. Thermophilic temperatures resulted in the highest percent reduction in NC concentration.« less
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Meat waste as feedstock for home composting: Effects on the process and quality of compost.
Storino, Francesco; Arizmendiarrieta, Joseba S; Irigoyen, Ignacio; Muro, Julio; Aparicio-Tejo, Pedro M
2016-10-01
Home composting is a powerful tool, which is spreading in different parts of the world, to reduce the generation of municipal waste. However, there is debate concerning the appropriateness, in terms of domestic hygiene and safety, of keeping a composter bin in the household deputed to kitchen waste of animal origin, such as meat or fish scraps and pet droppings. The purpose of our work was to study how the addition of meat scraps to household waste influences the composting process and the quality of the final compost obtained. We compared four raw material mixtures, characterized by a different combination of vegetable and meat waste and different ratios of woody bulking agent. Changes in temperature, mass and volume, phenotypic microbial diversity (by Biolog™) and organic matter humification were determined during the process. At the end of the experiment, the four composts were weighed and characterized by physicochemical analysis. In addition, the presence of viable weed seeds was investigated and a germination bioassay was carried out to determine the level of phytotoxicity. Finally, the levels of pathogens (Escherichia coli and Salmonella spp.) were also determined in the final compost. Here we show that the presence of meat waste as raw feedstock for composting in bins can improve the activity of the process, the physicochemical characteristics and maturity of the compost obtained, without significantly affecting its salinity, pH and phytotoxicity. Pathogen levels were low, showing that they can be controlled by an intensive management and proper handling of the composter bins. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Lu, Xin; Liu, Lizhu; Fan, Ruqin; Luo, Jia; Yan, Shaohua; Rengel, Zed; Zhang, Zhenhua
2017-10-01
Composting is one of the post-treatment methods for phytoremediation plants. Due to a high potential of water hyacinth to accumulate pollutants, the physicochemical parameters, microbial activity as well as fates of copper (Cu) and tetracyclines (TCs) were investigated for the different amended water hyacinth biomass harvested from intensive livestock and poultry wastewater, including unamended water hyacinth (W), water hyacinth amended with peat (WP), and water hyacinth amended with pig manure (WPM) during the composting process. Pig manure application accelerated the composting process as evidenced by an increase of temperature, electrical conductivity (EC), NH 4 -N, as well as functional diversity of microbial communities compared to W and WP treatments. Composting process was slowed down by high Cu, but not by TCs. The addition of peat significantly increased the residual fraction of Cu, while pig manure addition increased available Cu concentration in the final compost. Cu could be effectively transformed into low available (oxidizable) and residual fractions after fermentation. In contrast, less than 0.5% of initial concentrations of TCs were determined at the end of 60-day composting for all treatments in the final composts. The dissipation of TCs was accelerated by the high Cu concentration during composting. Therefore, composting is an effective method for the post-treatment and resource utilization of phytoremediation plants containing Cu and/or TCs.
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Asquer, Carla; Cappai, Giovanna; De Gioannis, Giorgia; Muntoni, Aldo; Piredda, Martina; Spiga, Daniela
2017-11-01
In this work the effects of selected types of biomass ash on the composting process and final product quality were studied by conducting a 96-day long experiment where the source separated organic fraction of municipal waste, mixed with wood prunings that served as bulking agent, was added with 0%, 2%, 4% and 8% wt/wt of biomass ash. The evolution over time of the main process parameters was observed, and the final composts were characterised. On the basis of the results, both the composting process and the quality of the final product were improved by ash addition. Enhanced volatile solids reduction and biological stability (up to 32% and 52%, respectively, as compared to the unamended product) were attained when ash was added, since ash favored the aerobic degradation by acting asa physical conditioner. In the final products, higher humification of organic matter (expressed in terms of the humification index, that was 2.25 times higher in the most-enriched compost than in the unamended one) and total Ca, K, Mg and P content were observed when ash was used. The latter aspect may influence the composts marketability positively, particularly with regards to potassium and phosphorus. The heavy metals content, that is regarded as the main environmental disadvantage when using ash asa composting additive, did not negatively affect the final composts quality. However, some other controversial effects of ash, related to the moisture and temperature values attained during the process, pH (8.8-9.2 as compared to 8.2 of the unamended compost) and electrical conductivity levels (up to 53% higher as compared to the unamended compost) in the final composts, were also observed. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Jiang, Yang; Ju, Meiting; Li, Weizun; Ren, Qingbin; Liu, Le; Chen, Yu; Yang, Qian; Hou, Qidong; Liu, Yiliang
2015-12-01
Keep composting matrix in continuous collision and friction under a relatively high-temperature can significantly accelerate the progress of composting. A bioreactor was designed according to the novel process. Using this technology, organic fertilizer could be produced within 96h. The electric conductivity (EC) and pH value reached to a stable value of 2.35mS/cm and 7.7 after 96h of fermentation. The total carbon/total nitrogen (TC/TN) and dissolved carbon/dissolved nitrogen (DC/DN) ratio was decrease from 27.3 and 36.2 to 17.4 and 7.6 respectively. In contrast, it needed 24days to achieve the similar result in traditional static composting (TSC). Compost particles with different size were analyzed to explore the rapid degradation mechanism of food waste. The evidence of anaerobic fermentation was firstly discovered in aerobic composting. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Song, Caihong; Li, Mingxiao; Jia, Xuan; Wei, Zimin; Zhao, Yue; Xi, Beidou; Zhu, Chaowei; Liu, Dongming
2014-01-01
This study investigated the impact of composting substrate types on the bacterial community structure and dynamics during composting processes. To this end, pig manure (PM), chicken manure (CM), a mixture of PM and CM (PM + CM), and a mixture of PM, CM and anaerobic digestion residue (ADR) (PM + CM + ADR) were selected for thermophilic composting. The bacterial community structure and dynamics during the composting process were detected and analysed by polymerase chain reaction–denaturing gradient gel electrophoresis (DGGE) coupled with a statistic analysis. The physical-chemical analyses indicated that compared to single-material composting (PM, CM), co-composting (PM + CM, PM + CM + ADR) could promote the degradation of organic matter and strengthen the ability of conserving nitrogen. A DGGE profile and statistical analysis demonstrated that co-composting, especially PM + CM + ADR, could improve the bacterial community structure and functional diversity, even in the thermophilic stage. Therefore, co-composting could weaken the screening effect of high temperature on bacterial communities. Dominant sequencing analyses indicated a dramatic shift in the dominant bacterial communities from single-material composting to co-composting. Notably, compared with PM, PM + CM increased the quantity of xylan-degrading bacteria and reduced the quantity of human pathogens. PMID:24963997
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Stanford, K; Reuter, T; Gilroyed, B H; McAllister, T A
2015-04-01
To investigate impact of sporulation and compost temperatures on feasibility of composting for disposal of carcasses contaminated with Bacillus anthracis. Two strains of B. cereus, 805 and 1391, were sporulated at either 20 or 37°C (Sporulation temperature, ST) and 7 Log10 CFU g(-1) spores added to autoclaved manure in nylon bags (pore size 50 μm) or in sealed vials. Vials and nylon bags were embedded into compost in either a sawdust or manure matrix each containing 16 bovine mortalities (average weight 617 ± 33 kg), retrieved from compost at intervals over 217 days and survival of B. cereus spores assessed. A ST of 20°C decreased spore survival by 1·4 log10 CFU g(-1) (P < 0·05) compared to a 37°C ST. Spore survival was strain dependent. Compost temperatures >55°C reduced spore survival (P < 0·05) and more frequently occurred in the sawdust matrix. Sporulation and compost temperatures were key factors influencing survival of B. cereus spores in mortality compost. Composting may be most appropriate for the disposal of carcasses infected with B. anthracis at ambient temperatures ≤20°C under thermophillic composting conditions (>55°C). © 2015 The Society for Applied Microbiology.
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NASA Astrophysics Data System (ADS)
Mounier, Stéphane; Abaker, Madi; Domeizel, Mariane; Rapetti, Nicola
2014-05-01
The maturity process of compost goes through several phases that have to be monitored in order to optimize the production process which in turn assure a good quality product and less time consumption. In order to estimate rapidly the phase where the compost is present and to measure the cellulose, the ratio C:N and the Stability Index Organic Matter (ISMO) a crucial parameter that needs to be monitored and controlled is the temperature. However, the temperature is not really a good indicator for the maturity of the compost because it is not constant and it depends on the mixing and environmental processes. The final measurements are performed at the end of the production process after certain time period that is subjectively determined by the producer. The work presented here is based on the optical properties of the organic matter that are observed each month for a period of six months. The organic matter of 5 composts was extracted by water and analyzed by UV-VIS spectroscopic technique [1] and 3D fluorescence emission technique [2]. The usual indexes were calculated (E2/E3, E4/E6, EBZ/EET, SUVA254), but also the PARAFAC decomposition of the 3D fluorescence response by Milori [3] and the Hx indexes [4]. The comparison of these results and the cellulose composition with the corresponding ISMO index indicates that the maturity process occurs more rapidly then the expectation of the producers. Further, the combination of the indicators gives useful information about different processes that take place during the maturity of the compost such as aromatization, the condensation and the stabilization of the parameters.
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Isolation of Thermus strains from hot composts (60 to 80 degrees C).
Beffa, T; Blanc, M; Lyon, P F; Vogt, G; Marchiani, M; Fischer, J L; Aragno, M
1996-01-01
High numbers (10(7) to 10(10) cells per g [dry weight]) of heterotrophic, gram-negative, rod-shaped, non-sporeforming, aerobic, thermophilic bacteria related to the genus Thermus were isolated from thermogenic composts at temperatures between 65 and 82 degrees C. These bacteria were present in different types of wastes (garden and kitchen wastes and sewage sludge) and in all the industrial composting systems studied (open-air windows, boxes with automated turning and aeration, and closed bioreactors with aeration). Isolates grew fast on a rich complex medium at temperatures between 40 and 80 degrees C, with optimum growth between 65 and 75 degrees C. Nutritional characteristics, total protein profiles, DNA-DNA hybridization (except strain JT4), and restriction fragment length polymorphism profiles of the DNAs coding for the 16S rRNAs (16S rDNAs) showed that Thermus strains isolated from hot composts were closely related to Thermus thermophilus HB8. These newly isolated T. thermophilus strains have probably adapted to the conditions in the hot-compost ecosystem. Heterotrophic, ovalspore-forming, thermophilic bacilli were also isolated from hot composts, but none of the isolates was able to grow at temperatures above 70 degrees C. This is the first report of hot composts as habitats for a high number of thermophilic bacteria related to the genus Thermus. Our study suggests that Thermus strains play an important role in organic-matter degradation during the thermogenic phase (65 to 80 degrees C) of the composting process. PMID:8633870
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Biowaste home composting: experimental process monitoring and quality control.
Tatàno, Fabio; Pagliaro, Giacomo; Di Giovanni, Paolo; Floriani, Enrico; Mangani, Filippo
2015-04-01
Because home composting is a prevention option in managing biowaste at local levels, the objective of the present study was to contribute to the knowledge of the process evolution and compost quality that can be expected and obtained, respectively, in this decentralized option. In this study, organized as the research portion of a provincial project on home composting in the territory of Pesaro-Urbino (Central Italy), four experimental composters were first initiated and temporally monitored. Second, two small sub-sets of selected provincial composters (directly operated by households involved in the project) underwent quality control on their compost products at two different temporal steps. The monitored experimental composters showed overall decreasing profiles versus composting time for moisture, organic carbon, and C/N, as well as overall increasing profiles for electrical conductivity and total nitrogen, which represented qualitative indications of progress in the process. Comparative evaluations of the monitored experimental composters also suggested some interactions in home composting, i.e., high C/N ratios limiting organic matter decomposition rates and final humification levels; high moisture contents restricting the internal temperature regime; nearly horizontal phosphorus and potassium evolutions contributing to limit the rates of increase in electrical conductivity; and prolonged biowaste additions contributing to limit the rate of decrease in moisture. The measures of parametric data variability in the two sub-sets of controlled provincial composters showed decreased variability in moisture, organic carbon, and C/N from the seventh to fifteenth month of home composting, as well as increased variability in electrical conductivity, total nitrogen, and humification rate, which could be considered compatible with the respective nature of decreasing and increasing parameters during composting. The modeled parametric kinetics in the monitored experimental composters, along with the evaluation of the parametric central tendencies in the sub-sets of controlled provincial composters, all indicate that 12-15 months is a suitable duration for the appropriate development of home composting in final and simultaneous compliance with typical reference limits. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Alves, David; Mato, Salustiano
2016-01-01
In general, in composting facilities the active, or intensive, stage of the process is done separately from the maturation stage, using a specific technology and time. The pre-composted material to be matured can contain enough biodegradable substrates to cause microbial proliferation, which in turn can cause temperatures to increase. Therefore, not controlling the maturation period during waste management at an industrial level can result in undesired outcomes. The main hypothesis of this study is that controlling the maturation stage through turning provides one with an optimized process when compared to the static approach. The waste used was sludge from a seafood-processing plant, mixed with shredded wood (1:2, v/v). The composting system consists of an intensive stage in a 600L static reactor, followed by maturation in triplicate in 200L boxes for 112 days. Two tests were carried out with the same process in reactor and different treatments in boxes: static maturation and turning during maturation when the temperature went above 55°C. PLFAs, organic matter, pH, electrical conductivity, forms of nitrogen and carbon, hydrolytic enzymes and respiratory activity were periodically measured. Turning significantly increased the duration of the thermophilic phase and consequently increased the organic-matter degradation. PCA differentiated significantly the two treatments in function of tracking parameters, especially pH, total carbon, forms of nitrogen and C/N ratio. So, stability and maturity optimum values for compost were achieved in less time with turnings. Whereas turning resulted in microbial-group stabilization and a low mono/sat ratio, static treatment produced greater variability in microbial groups and a high mono/sat ratio, the presence of more degradable substrates causes changes in microbial communities and their study during maturation gives an approach of the state of organic-matter degradation. Obtaining quality compost and optimizing the composting process requires using turning as a control mechanism during maturation. PMID:28002444
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Maeda, Koki; Morioka, Riki; Hanajima, Dai; Osada, Takashi
2010-01-01
The diversity and dynamics of the denitrifying genes (nirS, nirK, and nosZ) encoding nitrite reductase and nitrous oxide (N(2)O) reductase in the dairy cattle manure composting process were investigated. A mixture of dried grass with a cattle manure compost pile and a mature compost-added pile were used, and denaturing gradient gel electrophoresis was used for denitrifier community analysis. The diversity of nirK and nosZ genes significantly changed in the initial stage of composting. These variations might have been induced by the high temperature. The diversity of nirK was constant after the initial variation. On the other hand, the diversity of nosZ changed in the latter half of the process, a change which might have been induced by the accumulation of nitrate and nitrite. The nirS gene fragments could not be detected. The use of mature compost that contains nitrate and nitrite promoted the N(2)O emission and significantly affected the variation of nosZ diversity in the initial stage of composting, but did not affect the variation of nirK diversity. Many Pseudomonas-like nirK and nosZ gene fragments were detected in the stage in which N(2)O was actively emitted.
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Daur, Ihsanullah
2016-09-01
The present study addresses the problem of organic farmers' that needs local organic resources with their enhanced quality to effectively fertilize their agriculture crops. In accordance with the objective of the experiment that is about enhancing quality of compost, a blend of organic resources, comprising cow manure (CM), poultry manure (PM) and kitchen waste (KW) (2:1:1 ratio by volume) was composted with effective microorganisms (EM.1) (CompostEM.1) and without (Compostplain). During composting, temperature, pH, carbon, nitrogen, C/N ratio, total and diethylene triamine pentaacetic acid (DTPA)-extractable essential metal micronutrient (Fe3+, Cu2+, Zn2+, and Mn2+) contents of both the composts were recorded following the standard procedures. Low temperature range (24−24), low pH (6.7−7.2) and higher N-content (1.15−1.40) were recorded for CompostEM.1 as compared to Compostplain. Carbon degradation was also faster in CompostEM.1 than in Compostplain. Consequently, C/N ratio stabilization took 6 weeks in CompostEM.1 as compared to 18 weeks in Compostplain, leading to rapid completion of composting. Total concentration of micronutrients increased while their DTPA-extractable content decreased during the composting. Total micronutrient concentration was augmented more in Compostplain samples than in CompostEM.1. However, decrease in DTPA-extractable content was similar in both the composts. Increase in micronutrient content was attributed to decrease in organic matter weight, whereas decrease in metal micronutrients was attributed to the formation of organic matter-metal complexes during decomposition. Findings of the study indicated that effective micro-organisms enhanced composting process, however, further studies are required to evaluate its quality, especially effect on plant and soil.
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Barrena, Raquel; Pagans, Estel la; Artola, Adriana; Vázquez, Felícitas; Sánchez, Antoni
2007-06-01
Production of waste hair in the leather manufacturing industry is increasing every year due to the adoption of hair-save unhairing techniques, leaving the tanners with the problem of coping with yet another solid by-product. Numerous potential strategies for hair utilisation have been proposed. However, the use of hair waste as agricultural fertiliser is one of its most promising applications due to the high nitrogen content of hair. Agricultural value of hair can be increased by composting. This paper deals with the composting of hair from the unhairing of bovine hide. Results indicated that hair cannot be either composted on its own or co-composted with de-inking sludge, a chemical complementary co-substrate. However, good results were obtained when co-composted with raw sludge from a municipal wastewater treatment plant at hair:raw sludge weight ratios 1:1, 1:2 and, 1:4 in lab scale and pilot plant scale composters. In all cases, a more stable product was achieved at the end of the process. Composting in the pilot plant composter was effectively monitored using Static Respiration Indices determined at process temperature at sampling (SRI(T)) and at 37 degrees C (SRI(37)). Notably, SRI(T) values were more sensitive to changes in the biological activity. In contrast, Respiratory Quotient (RQ) values were not adequate to follow the development of the process.
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Composting toilets as a sustainable alternative to urban sanitation--a review.
Anand, Chirjiv K; Apul, Defne S
2014-02-01
In today's flush based urban sanitation systems, toilets are connected to both the centralized water and wastewater infrastructures. This approach is not a sustainable use of our water and energy resources. In addition, in the U.S., there is a shortfall in funding for maintenance and upgrade of the water and wastewater infrastructures. The goal of this paper was to review the current knowledge on composting toilets since this technology is decentralized, requires no water, creates a value product (fertilizer) and can possibly reduce the burden on the current infrastructure as a sustainable sanitation approach. We found a large variety of composting toilet designs and categorized the different types of toilets as being self contained or central; single or multi chamber; waterless or with water/foam flush, electric or non-electric, and no-mix or combined collection. Factors reported as affecting the composting process and their optimum values were identified as; aeration, moisture content (50-60%), temperature (40-65°C), carbon to nitrogen ratio (25-35), pH (5.5-8.0), and porosity (35-50%). Mass and energy balance models have been created for the composting process. However there is a literature gap in the use of this knowledge in design and operation of composting toilets. To evaluate the stability and safety of compost for use as fertilizer, various methods are available and the temperature-time criterion approach is the most common one used. There are many barriers to the use of composting toilets in urban settings including public acceptance, regulations, and lack of knowledge and experience in composting toilet design and operation and program operation. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Song, Caihong; Li, Mingxiao; Jia, Xuan; Wei, Zimin; Zhao, Yue; Xi, Beidou; Zhu, Chaowei; Liu, Dongming
2014-09-01
This study investigated the impact of composting substrate types on the bacterial community structure and dynamics during composting processes. To this end, pig manure (PM), chicken manure (CM), a mixture of PM and CM (PM + CM), and a mixture of PM, CM and anaerobic digestion residue (ADR) (PM + CM + ADR) were selected for thermophilic composting. The bacterial community structure and dynamics during the composting process were detected and analysed by polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) coupled with a statistic analysis. The physical-chemical analyses indicated that compared to single-material composting (PM, CM), co-composting (PM + CM, PM + CM + ADR) could promote the degradation of organic matter and strengthen the ability of conserving nitrogen. A DGGE profile and statistical analysis demonstrated that co-composting, especially PM + CM + ADR, could improve the bacterial community structure and functional diversity, even in the thermophilic stage. Therefore, co-composting could weaken the screening effect of high temperature on bacterial communities. Dominant sequencing analyses indicated a dramatic shift in the dominant bacterial communities from single-material composting to co-composting. Notably, compared with PM, PM + CM increased the quantity of xylan-degrading bacteria and reduced the quantity of human pathogens. © 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.
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Mathematical model of organic substrate degradation in solid waste windrow composting.
Seng, Bunrith; Kristanti, Risky Ayu; Hadibarata, Tony; Hirayama, Kimiaki; Katayama-Hirayama, Keiko; Kaneko, Hidehiro
2016-01-01
Organic solid waste composting is a complex process that involves many coupled physical, chemical and biological mechanisms. To understand this complexity and to ease in planning, design and management of the composting plant, mathematical model for simulation is usually applied. The aim of this paper is to develop a mathematical model of organic substrate degradation and its performance evaluation in solid waste windrow composting system. The present model is a biomass-dependent model, considering biological growth processes under the limitation of moisture, oxygen and substrate contents, and temperature. The main output of this model is substrate content which was divided into two categories: slowly and rapidly degradable substrates. To validate the model, it was applied to a laboratory scale windrow composting of a mixture of wood chips and dog food. The wastes were filled into a cylindrical reactor of 6 cm diameter and 1 m height. The simulation program was run for 3 weeks with 1 s stepwise. The simulated results were in reasonably good agreement with the experimental results. The MC and temperature of model simulation were found to be matched with those of experiment, but limited for rapidly degradable substrates. Under anaerobic zone, the degradation of rapidly degradable substrate needs to be incorporated into the model to achieve full simulation of a long period static pile composting. This model is a useful tool to estimate the changes of substrate content during composting period, and acts as a basic model for further development of a sophisticated model.
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Pérez-Lomas, A L; Delgado, G; Párraga, J; Delgado, R; Almendros, G; Aranda, V
2010-10-01
The effect of co-compost application from sewage sludge and pruning waste, on quality and quantity of soil organic carbon (SOC) in four Mediterranean agricultural soils (South Spain), was studied in soil microcosm conditions. Control soil samples (no co-compost addition) and soils treated with co-composts to a rate equivalent of 140 Mg ha(-1) were incubated for 90 days at two temperatures: 5 and 35 degrees C. The significances of incubation temperature and the addition of co-compost, on the evolution of the different fractions of SOC, were studied using a 2(3) factorial design. The co-compost amendment increased the amounts of humic fractions: humic acids (HA) (1.9 times), fulvic acids (FA) (3.3 times), humin (1.5 times), as well as the free organic matter (1.4 times) and free lipids (21.8 times). Incubation of the soils enhanced its biological activity mainly in the amended soils and at 35 degrees C, leading to progressive SOC mineralization and humification, concomitant to the preferential accumulation of HA. The incubation results show large differences depending on temperature and soil types. This fact allows us to select suitable organic amendment for the soil when a rapid increase in nutrients through mineralization is preferred, or in cases intending the stabilization and preservation of the SOC through a process of humification. In soils with HA of more than 5 E(4)/E(6) ratio, the incubation temperature increased rates of mineralization and humification, whereas lower temperatures limited the extent of both processes. In these soils the addition of co-compost in spring or summer is the most recommendable. In soils with HA of lower E(4)/E(6) ratio (<5), the higher temperature favoured mineralization but not humification, whereas the low temperature maintained the SOC levels and even increased the HA/FA ratio. In these soils the moment of addition of organic amendment should be decided depending on the effect intended. On the other hand, the lower the SOC content in the original soil, the greater are the changes observed in the SOC after amendment with co-compost. The results suggest that proper recommendations for optimum organic matter evolution after soil amendment is possible after considering a small set of characteristics of soil and the corresponding soil organic matter fractions, in particular HA. (c) 2010 Elsevier Ltd. All rights reserved.
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Nakasaki, Kiyohiko; Araya, Shogo; Mimoto, Hiroshi
2013-09-01
In this study, the yeast strain Pichia kudriavzevii RB1 was used as an inoculum to accelerate organic matter degradation of rabbit food with added organic acids, which was used as a model food waste for composting. The RB1 strain rapidly degraded the organic acids present in the raw compost material, leading to an increase in pH beyond the neutral level, within 2 days. Both mesophilic and thermophilic bacteria proliferated faster in the compost with RB1 inoculation than in that without inoculation. Although the yeast died with the increase in compost temperature, it affected the early stages of composting prior to the thermophilic stage and accelerated the composting process by 2 days by eliminating the initial lag phase seen in the growth of other microorganisms. Moreover, populations of Bacillus thermoamylovorans, Bacillus foraminis, and Bacillus coagulans became dominant during the thermophilic stages of both composting with and without RB1 inoculation. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Wang, Gui-Zhen; Li, Zhao-Jun; Zhang, Shu-Qing; Ma, Xiao-Tong; Liang, Yong-Chao
2013-02-01
In order to illustrate the degradation of tetracyclines (TCs) and their influences on process parameters during the period of chicken feces aerobic-composting, the degradation of oxytetracycline (OTC), a kind of TCs and its effects on parameters during the period of chick feces aerobic-composting including temperature, pH, and germination index were investigated using the method of aerobic-composting. The contents of OTC decreased gradually with composting time. The degradation rate was high before 10 d, and then decreased gradually. The differences in OTC degradation among the OTC treatments were also found. The degradation rate of OTC was higher at the level of 25 mg.kg-1, than that of other levels. The degradation curve of OTC could be described by the first-order kinetic model, and the correlation coefficients ranged from 0. 911 1 to 0. 9913. The impacts of OTC on chick feces composting were found. OTC could decrease the rising rate of composting temperature and make the high temperature (> or =50 degrees C) period shorter than that of the control. The values of pH, TN, WSC, and the content of NH: -N of composting were 4.58%, 12.62%, 49.06%, and 35.30% higher than those of the control. The impacts of OTC on maturity of chicken feces composting was not found when the OTC addition contents were lower than 50 mg.kg-1. However, the strong impacts of OTC on maturity of chicken feces composting were found when the OTC addition contents were higher than 50 mg.kg-1. The rates of NH+4 -N to NO-3 -N, and GI were much higher than 0. 5 and lower than 80% , respectively. Theses results suggest that OTC have strong impacts on chicken feces composting when the contents of TOC was higher than 50 mg.kg-1, although OTC have the short half-life period ranged from 1.79-4.88 d.
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Komar, S; Miskewitz, R; Westendorf, M; Williams, C A
2012-03-01
Our objective in this study is to compare 4 of the most common bedding materials used by equine operations on the chemical and physical characteristics of composted equine stall waste. Twelve Standardbred horses were adapted to the barn and surrounding environment for 2 wk before the start of the study. Groups of 3 horses were bedded on 1 of 4 different bedding types (wood shavings, pelletized wood materials, long straw, and pelletized straw) for 16 h per day for 18 d. Stalls were cleaned by trained staff daily, and all contents removed were weighed and stored separately by bedding material on a level covered concrete pad for the duration of the study. Compost piles were constructed using 3 replicate piles of each bedding type in a randomized complete block design. Each pile was equipped with a temperature sensor and data logger. Water was added and piles were turned weekly throughout the 100-d compost process. Initial and final samples were taken, dried, and analyzed for DM mass, OM, inorganic nitrogen (nitrate-N and ammonium-N), electrical conductivity, and soluble (plant-available) nutrients. Data were analyzed using the GLM procedure, and means were separated using Fischer's protected LSD test (P < 0.05). No significant temperature differences were observed among the bedding materials. The composting process resulted in significant reductions (P < 0.05) in DM mass for each of the 4 bedding materials. The composting process resulted in significant reductions (P < 0.05) in OM and C:N ratio for all 4 bedding materials. The composted long straw material had greater concentrations of total Kjeldahl nitrogen (P < 0.05), nitrate-N (P < 0.05), and ammonium-N (P < 0.05) than the composted wood shavings. This study demonstrated that incorporating a simple aerobic composting system may greatly reduce the overall volume of manure and yield a material that is beneficial for land application in pasture-based systems. The straw-based materials may be better suited for composting and subsequent land application; however, factors such as suitability of the bedding material for equine use, material cost, labor, and availability must be considered when selecting a bedding material.
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Zhang, Lili; Li, Lijuan; Pan, Xiaoguang; Shi, Zelu; Feng, Xihong; Gong, Bin; Li, Jian; Wang, Lushan
2018-01-01
As a consequence of intensive feeding, the bulk deposition of livestock manure causes severe environmental problems. Composting is a promising method for waste disposal, and the fermentation process is driven by microbial communities. However, chicken manure contains diverse gut microbes, mainly species derived from Proteobacteria , which may include pathogens that threaten human health. To evaluate composting as a harmless treatment of livestock manure, the dynamics of the microbiota in two chicken manure composts were studied, and the influences of adding maize straw on the compost microbiota were compared. The results revealed that microbes from Firmicutes including Bacillus and Lentibacillus are the most dominant degraders with a strong amino acid metabolism, and they secrete a diverse array of proteases as revealed in metaproteomics data. The addition of maize straw to the chicken manure compost accelerated species succession at the initial stage, and stimulated carbohydrate metabolism in the dominant microbiota. Besides, under the resulting high temperature (>70°C) conditions, the relative abundance of Proteobacteria was reduced by 78% in composts containing maize straw by day 4, which was faster than in compost without added maize straw, in which the abundance was reduced by 66%. Adding maize straw to chicken manure composts can therefore increase the fermentation temperature and inhibit the growth of Proteobacteria . In general, these findings provide increased insight into the dynamic changes among the dominant functional microbiota in chicken manure composts, and may contribute to the optimization of livestock manure composting on an industrial scale.
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Mathematical modeling of olive mill waste composting process.
Vasiliadou, Ioanna A; Muktadirul Bari Chowdhury, Abu Khayer Md; Akratos, Christos S; Tekerlekopoulou, Athanasia G; Pavlou, Stavros; Vayenas, Dimitrios V
2015-09-01
The present study aimed at developing an integrated mathematical model for the composting process of olive mill waste. The multi-component model was developed to simulate the composting of three-phase olive mill solid waste with olive leaves and different materials as bulking agents. The modeling system included heat transfer, organic substrate degradation, oxygen consumption, carbon dioxide production, water content change, and biological processes. First-order kinetics were used to describe the hydrolysis of insoluble organic matter, followed by formation of biomass. Microbial biomass growth was modeled with a double-substrate limitation by hydrolyzed available organic substrate and oxygen using Monod kinetics. The inhibitory factors of temperature and moisture content were included in the system. The production and consumption of nitrogen and phosphorous were also included in the model. In order to evaluate the kinetic parameters, and to validate the model, six pilot-scale composting experiments in controlled laboratory conditions were used. Low values of hydrolysis rates were observed (0.002841/d) coinciding with the high cellulose and lignin content of the composting materials used. Model simulations were in good agreement with the experimental results. Sensitivity analysis was performed and the modeling efficiency was determined to further evaluate the model predictions. Results revealed that oxygen simulations were more sensitive on the input parameters of the model compared to those of water, temperature and insoluble organic matter. Finally, the Nash and Sutcliff index (E), showed that the experimental data of insoluble organic matter (E>0.909) and temperature (E>0.678) were better simulated than those of water. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Li, Ronghua; Wang, Quan; Zhang, Zengqiang; Zhang, Guangjie; Li, Zhonghong; Wang, Li; Zheng, Jianzhong
2015-01-01
The effects of the corn stalk charred biomass (CB) prepared at different pyrolysis temperatures as additives on nutrient transformation during aerobic composting of pig manure were investigated. The results showed that the addition of CB carbonized at different temperatures to pig manure compost significantly influenced the compost temperature, moisture, pH, electrical conductivity, organic matter degradation, total nitrogen, [Formula: see text] and NH3 variations during composting. Compared with control and adding CB charred at lower temperature treatments, the addition of CB prepared over 700°C resulted in higher pH (over 9.2) and NH3 emission and lower potherb mustard seed germination index value during the thermophilic phase. Peak temperatures of composts appeared at 7 days for control and 11 days for CB added treatments. During 90 days composting, the organic matter degradation could be increased over 14.8-29.6% after adding of CB in the compost mixture. The introduction of CB in pig manure could prolong the thermophilic phase, inhibit moisture reduce, facilitate the organic matter decomposition, reduce diethylene triamine pentaacetic acid (DTPA) extractable Zn and Cu contents in pig manure composts and increase ryegrass growth. The study indicated that the corn stalk CB prepared around 500°C was a suitable additive in pig manure composting.
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Nasri, Behzad; Brun, Florent; Fouché, Olivier
2017-11-05
One of the most undesired wastes is the human excreta due to the socio-environmental pressure. Otherwise, the nutriments contained in human excreta could be used as fertilizers to enrich the soil. Familial waterless litter composting toilets (FWLCT) are an alternative for locations where a centralized sewerage network cannot be provided or where there is a lack of standard urban infrastructure including roads, electricity, and water supply. The scientific researches on the composting techniques, the methods of control of the composting processors, and the rate of produced leachate are very limited. In this research, the composting systems included a feces and urine collection device. In each passage, the litter (carbonaceous material) is added to the excreta. Regularly, the buckets were emptied into a composting device located outside the house to which an additional portion of carbonaceous materials can be added. Monitoring was carried out on five rural and one urban familial composting areas in France for 1.5 years. The physiochemical and microbiological properties of the compost and leachate have been monitored and measured in compliance with the protocols. The results show that one of the main problems of this system of human excreta treatment is that the composting process does not achieve a significant rise in temperature and does not allow reaching the optimum temperatures (> 50 °C). Otherwise, from an agronomic point of view, the obtained compost is not rich enough in nutriments to be a good compost as soil fertilizer. But it can be used as a soil conditioner. The average leachate flux from the composters is 1.79 L/day. Because of the very short stay time in the piles, the leachate is contaminated by harmful bacteria and should be treated by another sanitation system.
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Zhao, Gui-Hong; Yu, Yan-Ling; Zhou, Xiang-Tong; Lu, Bin-Yu; Li, Zi-Mu; Feng, Yu-Jie
2017-05-01
The main characteristic of discarded flue-cured tobacco leaves is their high nicotine content. Aerobic composting is an effective method to decrease the nicotine level in tobacco leaves and stabilize tobacco wastes. However, high levels of nicotine in discarded flue-cured tobacco leaves complicate tobacco waste composting. This work proposes a drying pretreatment process to reduce the nicotine content in discarded flue-cured tobacco leaves and thus enhance its carbon-to-nitrogen ratio to a suitable level for composting. The effect of another pretreatment method, particle size adjustment, on composting efficiency was also tested in this work. The results indicated that the air-dried (nicotine content: 1.35%) and relatively long discarded flue-cured tobacco leaves (25 mm) had a higher composting efficiency than damp (nicotine content: 1.57%) and short discarded flue-cured tobacco leaves (15 mm). When dry/25 mm discarded flue-cured tobacco leaves mixed with tobacco stems in an 8:2 ratio was composted at a temperature above 55 °C for 9 days, the nicotine content dropped from 1.29% to 0.28%. Since the discarded flue-cured tobacco leaves was successfully composted to a fertile and harmless material, the germination index values increased to 85.2%. The drying pretreatment and particle size adjustment offered ideal physical and chemical conditions to support microbial growth and bioactivity during the composting process, resulting in efficient conversion of discarded flue-cured tobacco leaves into a high quality and mature compost.
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Quecholac-Piña, Xochitl; García-Rivera, Mariel Anel; Espinosa-Valdemar, Rosa María; Vázquez-Morillas, Alethia; Beltrán-Villavicencio, Margarita; Cisneros-Ramos, Adriana de la Luz
2017-11-01
Plastics are widely used in the production of short-life products, which are discarded producing an accumulation of these materials and problems due to their persistence in the environment and waste management systems. Degradable plastics (compostable, oxodegradable) have been presented as an alternative to decrease the negative effect of plastic waste. In this research, the feasibility of degrading a commercially available compostable film and oxodegradable polyethylene, with and without previous abiotic oxidation, is assessed in a home composting system. Reactors (200 L) were used to degrade the plastic films along with a mixture of organic food waste (50 %), mulch (25 %), and dry leaves (25 %), amended with yeast and a solution of brown sugar to increase the speed of the process. The presence of the plastic film did not affect the composting process, which showed an initial increase in temperature and typical profiles for moisture content, pH, with a final C/N of 17.4. After 57 days, the compostable plastic has decreased its mechanical properties in more than 90 %, while the oxodegradable film did not show significant degradation if it was not previously degraded by UV radiation. The use of these plastics should be assessed against the prevailing waste management system in each city or country. In the case of Mexico, which lacks the infrastructure for industrial composting, home composting could be an option to degrade compostable plastics along organic waste. However, more testing is needed in order to set the optimal parameters of the process.
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Yossa, Irene; Macarisin, Dumitru; Millner, Patricia
2015-01-01
This study investigated the effect of a 30-cm covering of finished compost (FC) on survival of Escherichia coli O157:H7 and Salmonella spp. in active static and windrow composting systems. Feedstocks inoculated with E. coli O157:H7 (7.41 log CFU/g) and Salmonella (6.46 log CFU/g) were placed in biosentry tubes (7.5-cm diameter, 30-cm height) at three locations: (i and ii) two opposing sides at the interface between the FC cover layer (where present) and the feedstock material (each positioned approximately 10 cm below the pile's surface) and (iii) an internal location (top) (approximately 30 cm below the surface). On specific sampling days, surviving populations of inoculated E. coli O157:H7 and Salmonella, generic E. coli, and coliforms in compost samples were determined. Salmonella spp. were reduced significantly within 24 h in windrow piles and were below the detection limit after 3 and 7 days at internal locations of windrow and static piles containing FC covering, respectively. Likewise, E. coli O157:H7 was undetectable after 1 day in windrow piles covered with finished compost. Use of FC as a covering layer significantly increased the number of days that temperatures in the windrows remained ≥55°C at all locations and in static piles at internal locations. These time-temperature exposures resulted in rapid reduction of inoculated pathogens, and the rate of bacterial reduction was rapid in windrow piles. The sample location significantly influenced the survival of these pathogens at internal locations compared to that at interface locations of piles. Finished compost covering of compost piles aids in the reduction of pathogens during the composting process. PMID:25576620
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Tashiro, Yukihiro; Tabata, Hanae; Itahara, Asuka; Shimizu, Natsuki; Tashiro, Kosuke; Sakai, Kenji
2016-11-01
A unique compost, Satsuma soil, is produced from three types of wastewater sludge using hyper-thermal processes at temperatures much higher than that of general thermophilic processes in Kagoshima City, Japan. We analyzed the bacterial community structures of this hyper-thermal compost sample and other sludges and composts by a high-throughput barcoded pyrosequencing method targeting the 16S rRNA gene. In total, 621,076 reads were derived from 17 samples and filtered. Artificial sequences were deleted and the reads were clustered based on the operational taxonomic units (OTUs) at 97% similarity. Phylum-level analysis of the hyper-thermal compost revealed drastic changes of the sludge structures (each relative abundance) from Firmicutes (average 47.8%), Proteobacteria (average 22.3%), and Bacteroidetes (average 10.1%) to two main phyla including Firmicutes (73.6%) and Actinobacteria (25.0%) with less Proteobacteria (∼0.3%) and Bacteroidetes (∼0.1%). Furthermore, we determined the predominant species (each relative abundance) of the hyper-thermal compost including Firmicutes related to Staphylococcus cohnii (13.8%), Jeotgalicoccus coquinae (8.01%), and Staphylococcus lentus (5.96%), and Actinobacteria related to Corynebacterium stationis (6.41%), and found that these species were not predominant in wastewater sludge. In contrast, we did not observe any common structures among eight other composts produced, using the hyper-thermal composts as the inoculums, under thermophilic conditions from different materials. Principle coordinate analysis of the hyper-thermal compost indicated a large difference in bacterial community structures from material sludge and other composts. These results suggested that a distinct bacterial community structure was formed by hyper-thermal composting. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
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Co-composting of eggshell waste in self-heating reactors: monitoring and end product quality.
Soares, Micaela A R; Quina, Margarida M J; Quinta-Ferreira, Rosa M
2013-11-01
Industrial eggshell waste (ES) is classified as an animal by-product not intended to human consumption. For reducing pathogen spreading risk due to soil incorporation of ES, sanitation by composting is a pre-treatment option. This work aims to evaluate eggshell waste recycling in self-heating composting reactors and investigate ES effect on process evolution and end product quality. Potato peel, grass clippings and rice husks were the starting organic materials considered. The incorporation of 30% (w/w) ES in a composting mixture did not affect mixture biodegradability, nor its capacity to reach sanitizing temperatures. After 25 days of composting, ES addition caused a nitrogen loss of about 10 g N kg(-1) of initial volatile solids, thus reducing nitrogen nutritional potential of the finished compost. This study showed that a composting mixture with a significant proportion of ES (30% w/w) may be converted into calcium-rich marketable compost to neutralize soil acidity and/or calcium deficiencies. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Survival of Human Pathogens in Composted Sewage
Wiley, B. Beauford; Westerberg, Stephen C.
1969-01-01
Studies were conducted to assess the effectiveness of an aerobic composter in destroying pathogens that may possibly be present in raw sewage sludge. Experiments conducted in this study were designed to determine whether or not selected indicator organisms (i.e., Salmonella newport, poliovirus type 1, Ascaris lumbricoides ova, and Candida albicans) could survive the composting process. The results of the assay showed that after 43 hr of composting, no viable indicator organisms could be detected. The poliovirus type I was the most sensitive, being inactivated within the first hour, whereas C. albicans was the most resistant, requiring more than 28 hr of composting for its inactivation. The data from this study indicated that aerobic composting of sewage sludge would destroy the indicator pathogens when a temperature of 60 to 70 C is maintained for a period of 3 days. PMID:4313209
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Vieira, Fabricio Rocha; Pecchia, John Andrew
2018-02-01
Substrate preparation (i.e., composting) for Agaricus bisporus cultivation is the most critical point of mushroom production. Among many factors involved in the composting process, the microbial ecology of the system is the underlying drive of composting and can be influenced by composting management techniques. Pasteurization temperature at the beginning of phase II, in theory, may influence the bacterial community and subsequently the "selectivity" and nutrition of the final substrate. Therefore, this hypothesis was tested by simulation in bioreactors under different pasteurization conditions (57 °C/6 h, 60 °C/2 h, and 68 °C/2 h), simulating conditions adopted by many producers. Bacterial diversity, based on 16S ribosomal RNA obtained by high-throughput sequencing and classified in operational taxonomic units (OTUs), was greater than previously reported using culture-dependent methods. Alpha diversity estimators show a lower diversity of OTUs under a high-temperature pasteurization condition. Bacillales order shows a relatively higher OTU abundance under a high-pasteurization temperature, which also was related to high ammonia emission measurements. On the other hand, beta diversity analysis showed no significantly changes in the bacterial community structure under different conditions. Agaricus bisporus mycelium growth during a standard spawn run period was significantly slower in the compost pasteurized at high temperature. Since the bacterial community structure was not greatly affected by different pasteurization conditions but by-products left (e.g., ammonia) at the end of compost conditioning varied, further studies need to be conducted to determine the functional role of the microbial communities found during substrate preparation for Agaricus bisporus cultivation.
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Dynamic modeling the composting process of the mixture of poultry manure and wheat straw.
Petric, Ivan; Mustafić, Nesib
2015-09-15
Due to lack of understanding of the complex nature of the composting process, there is a need to provide a valuable tool that can help to improve the prediction of the process performance but also its optimization. Therefore, the main objective of this study is to develop a comprehensive mathematical model of the composting process based on microbial kinetics. The model incorporates two different microbial populations that metabolize the organic matter in two different substrates. The model was validated by comparison of the model and experimental data obtained from the composting process of the mixture of poultry manure and wheat straw. Comparison of simulation results and experimental data for five dynamic state variables (organic matter conversion, oxygen concentration, carbon dioxide concentration, substrate temperature and moisture content) showed that the model has very good predictions of the process performance. According to simulation results, the optimum values for air flow rate and ambient air temperature are 0.43 l min(-1) kg(-1)OM and 28 °C, respectively. On the basis of sensitivity analysis, the maximum organic matter conversion is the most sensitive among the three objective functions. Among the twelve examined parameters, μmax,1 is the most influencing parameter and X1 is the least influencing parameter. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Autoheated thermophilic aerobic digestion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deeny, K.; Hahn, H.; Leonhard, D.
1991-10-01
Autothermal thermophilic aerobic digestion (ATAD) is first and foremost a digestion process, the primary purpose of which is to decompose a portion of the waste organic solids generated from wastewater treatment. As a result of the high operating temperature, digestion is expected to occur within a short time period (6 days) and accomplish a high degree of pathogen reduction. ATAD systems are two-stage aerobic digestion processes that operate under thermophilic temperature conditions (40 to 80C) without supplemental heat. Like composting, the systems rely on the conservation of heat released during digestion itself to attain and sustain the desired operating temperature.more » Typical ATAD systems operate at 55C and may reach temperatures of 60 to 65C in the second-stage reactor. Perhaps because of the high operating temperature, this process has been referred to as Liquid Composting.' Major advantages associated with thermophilic operation include high biological reaction rates and a substantial degree of pathogen reduction.« less
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NASA Astrophysics Data System (ADS)
Trisakti, B.; Mhardela, P.; Husaini, T.; Irvan; Daimon, H.
2018-02-01
This research was to determine the effect of pieces sizes of oil palm empty fruit bunch (EFB) on the composting of EFB mixed with activated liquid organic fertilizer (ALOF) in a basket composter in order to obtain high quality compost. The composting process was started by cutting the EFB into pieces with varies sizes, inserting the EFB pieces into basket composter (33 cm W × 28 cm L × 40 cm H), and adding ALOF until moisture content (MC) in the range of 55-65%. During composting, the compost pile was turned every 3 days and the MC was maintained at 55-65% range by adding the ALOF. The sizes of the EFB pieces were varied into <1, 1-3, 4-7, 8-11, and 12-15 cm. The parameters analysed during the composting were temperature, pH, MC, compost weight, water holding capacity (WHC), CN ratio, and the quality of the final compost. Composting was carried out for 40 days and the best result obtained at EFB pieces size was 1-3 cm with compost characteristic were pH 9.0; MC 52.59%; WHC 76%; CN ratio 12.15; N 1.96%; P 0.58%; and K 0. 95%.
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NASA Astrophysics Data System (ADS)
Trisakti, B.; Lubis, J.; Husaini, T.; Irvan
2017-03-01
Composting of Empty Fruit Bunch (EFB) by mixing it with activated liquid organic fertilizer (ALOF) is an alternative way in the utilization of solid waste produced from the palm oil mill (POM). This research was to determine the effect of turning frequency on the rate of composting of EFB mixed with ALOF in a basket composter. The composting process was started with cutting the EFB into pieces with size 1-3 cm, inserting the EFB pieces into basket composter (33 cm W × 28 cm L × 40 cm H), and adding ALOF until moisture content (MC) in the range of 55-65%. During composting, the MC was maintained at 55-65% range by adding the ALOF. The turning frequency on each composter was varied i.e. once in every 1, 2, 3, 4, and 5 days. The parameters analysed during composting were temperature, pH, MC, compost weight, water holding capacity (WHC), CN ratio, and the quality of the final compost. Composting was carried out for 40 days and the best result obtained at turning frequency was 3 days. The best compost characteristic was pH 9.0; MC 57.24%; WHC 76%; CN ratio 12.15%; P 0.58%; and K 0. 95%.
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Latifah, Omar; Ahmed, Osumanu Haruna; Susilawati, Kassim; Majid, Nik Muhamad
2015-04-01
The availability of paddy husk from rice processing plants remains high owing to increase in the worldwide rice consumption. Increasing demand for chicken products leads to poultry wastes production. Co-composting of the aforementioned wastes could solve the indiscriminate disposal of these wastes. Thus, co-composting of paddy husk and chicken slurry with clinoptilolite zeolite and urea as additive was carried out. Clinoptilolite zeolite was used to enhance ammonium and nitrate retention in the compost. Temperature of the compost was monitored three times daily for 55 days. Cation exchange capacity, organic matter, ash, humic acids, pH, total C, N, C/N ratio; total P, exchangeable Ca, Mg, K, NH4+, NO3-, and heavy metals contents were determined using standard procedures. pH, total N, humic acids, ash, NH4+, NO3-, P, Ca, Mg, and K contents increased but the salinity, heavy metals contents, and microbial population were low after the co-composting process. Zea mays L. (test crop) seed germination rate in distilled water and the compost were not significantly different. Growth of Spinach oleracea (test crop) on a peat-based growing medium and the compost was also not significantly different. These findings were possible because the clinoptilolite zeolite used in co-composting reduced accumulation of heavy metals that may have damage effects on the test crops. Mature compost with good agronomic properties can be produced by co-composting chicken slurry and paddy husk using clinoptilolite zeolite and urea as additives. © The Author(s) 2015.
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Home composting using different ratios of bulking agent to food waste.
Guidoni, Lucas Lourenço Castiglioni; Marques, Roger Vasques; Moncks, Rodrigo Bilhalva; Botelho, Fabiana Torma; da Paz, Matheus Francisco; Corrêa, Luciara Bilhalva; Corrêa, Érico Kunde
2018-02-01
The negative environmental impacts associated with home composting may be due to the absence of a defined operation criteria for the degradation process. In addition to the potentially low environmental impact in terms of energy and water usage, which is minimal to the manufacture of the composting unit and avoiding the processing and transportation of waste or byproduct, composting at home can also promote a reduction in the emission of unpleasant gases. The proportion of the food waste and bulking agents in the composting mixture may be decisive to fulfill good practices of waste stabilization. The aim of this study was to investigate how different ratios of bulking agent and organic household waste can affect the progress and outcome of the composting process. Three treatments, varying in the ratio of rice husk: raw fruit and vegetable leftovers (70:30, 50:50, 30:70; v:v) were used in a home composting system on a pilot scale. Results show that the proportion of starting materials used in the composting mixture influenced the degradation of organic matter, nitrogen dynamics of the process and its toxicity on germinating plants. The proportions with greater amounts of food waste had higher concentrations of mineral matter, higher peak temperature, and a better initial carbon-to-nitrogen ratio, while the proportion containing 70% of bulking agent lacked odors and leachate generation and showed a low nitrogen loss. A higher proportion of food waste presented better conditions for microbiological development and less time to obtain characteristics of matured composts. A higher proportion of bulking agents resulted in favorable conditions for household handling and less potential for environmental impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Evaluation of composition and performance of composts derived from guacamole production residues.
González-Fernández, J Jorge; Galea, Zesay; Alvarez, José M; Hormaza, J Iñaki; López, Rafael
2015-01-01
The utilization of organic wastes to improve soils or for growth media components in local farms and nurseries can reduce the environmental pollution linked to waste disposal while increasing the sustainability of crop production. This approach could be applied to waste products generated from the production of guacamole (an emerging activity in the avocado production areas in mainland Spain), where appropriate treatment of this oily and doughy waste product has not been previously reported. The aim of this work is to study the feasibility of co-composting guacamole production residues (GR) with garden pruning waste (PW) as bulking agent, and the possible use of the compost produced depending on its quality. A windrow composting trial using three GR:PW ratios, 2:1, 1:2, and 1:7 was carried out. Temperature, moisture, organic matter, and C/N ratio were used to follow the evolution of the composting process during 7 months. After an additional 3-month curing period, composts were sieved to less than 10 mm and a set of European quality criteria was used to assess compost quality and intended use. In general, the 3 composting mixtures followed the classical process evolution, with minor differences among them. The 1:2 GR:PW ratio appeared most adequate for combining better process evolution and maximum GR ratio. Except for their high pH that limits their use as growing media component in some particular cases, the obtained composts fulfilled the more stringent European standards for commercial composts. Self-heating tests confirmed the high stability of the composts produced. The germination of cress by the direct contact method was satisfactory for composts GR:PW 1:2 and 1:7, showing no signs of toxicity. Avocado seedlings planted in substrates containing 67% of the GR:PW composts exhibited greater plant growth than those in the control treatment, and with no signs of phytotoxicity. The results open an interesting opportunity for the sustainable treatment of avocado fruit by-products derived from guacamole and avocado oil processing. Copyright © 2014 Elsevier Ltd. All rights reserved.
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[Production of a compost accelerator inoculant].
Medina Lara, M Socorro; Quintero Lizaola, Roberto; Espinosa Victoria, David; Alarcón, Alejandro; Etchevers Barra, Jorge D; Trinidad Santos, Antonio; Conde Martínez, F Víctor
2017-10-26
Composting was performed using a mixture of ovine manure and straw. Inoculum was extracted at five different phases of the composting process (18, 23, 28, 33 and 38 days after the start of the composting process) and its effect on reducing biotransformation time was evaluated in the composted ovine manure. The samples were preserved in a deep freezer, then lyophilized to obtain the inoculum, 50g of which was added to each treatment in the second experimental phase. Six treatments were established; C=straw (P)+ovine manure (E), T1=P+ E+inoculum 18 days after the start of the composting process (I18), T2=P+E+I23, T3=P+E+I28, T4=P+E+I33, T5=P+E+I38, with three replications. Treatments were placed in a controlled-environment chamber at 45% relative humidity and 30°C along with flasks containing 50g of material to measure daily production, CO 2 accumulation, temperature, pH, electric conductivity (dS/m), organic matter (%), total nitrogen (%), total carbon (%), C: N ratio, particle size (Tp) and bulk density (g/l). CO 2 production (mg) showed a significant difference (p ≤.05) of treatments T2 and T5 with respect to the others, which demonstrated that the inoculum of these treatments accelerated the dynamics of microorganisms and the composting process. The quality and maturity of the compost are guaranteed as the amount of CO 2 decreases. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
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Komilis, Dimitrios; Evangelou, Alexandros; Voudrias, Evangelos
2011-09-01
The management of dewatered wastewater sludge is a major issue worldwide. Sludge disposal to landfills is not sustainable and thus alternative treatment techniques are being sought. The objective of this work was to determine optimal mixing ratios of dewatered sludge with other organic amendments in order to maximize the degradability of the mixtures during composting. This objective was achieved using mixture experimental design principles. An additional objective was to study the impact of the initial C/N ratio and moisture contents on the co-composting process of dewatered sludge. The composting process was monitored through measurements of O(2) uptake rates, CO(2) evolution, temperature profile and solids reduction. Eight (8) runs were performed in 100 L insulated air-tight bioreactors under a dynamic air flow regime. The initial mixtures were prepared using dewatered wastewater sludge, mixed paper wastes, food wastes, tree branches and sawdust at various initial C/N ratios and moisture contents. According to empirical modeling, mixtures of sludge and food waste mixtures at 1:1 ratio (ww, wet weight) maximize degradability. Structural amendments should be maintained below 30% to reach thermophilic temperatures. The initial C/N ratio and initial moisture content of the mixture were not found to influence the decomposition process. The bio C/bio N ratio started from around 10, for all runs, decreased during the middle of the process and increased to up to 20 at the end of the process. The solid carbon reduction of the mixtures without the branches ranged from 28% to 62%, whilst solid N reductions ranged from 30% to 63%. Respiratory quotients had a decreasing trend throughout the composting process. Copyright © 2011 Elsevier Ltd. All rights reserved.
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[Co-composting high moisture vegetable waste and flower waste in a sequential fed operation].
Zhang, Xiangfeng; Wang, Hongtao; Nie, Yongfeng
2003-11-01
Co-composting of high moisture vegetable wastes (celery and cabbage) and flower wastes (carnation) were studied in a sequential fed bed. The preliminary materials of composting were celery and carnation wastes. The sequential fed materials of composting were cabbage wastes and were fed every 4 days. Moisture content of mixture materials was between 60% and 70%. Composting was done in an aerobic static bed of composting based temperature feedback and control via aeration rate regulation. Aeration was ended when temperature of the pile was about 40 degrees C. Changes of composting of temperature, aeration rate, water content, organic matter, ash, pH, volume, NH4(+)-N, and NO3(-)-N were studied. Results show that co-composting of high moisture vegetable wastes and flower wastes, in a sequential fed aerobic static bed based temperature feedback and control via aeration rate regulation, can stabilize organic matter and removal water rapidly. The sequential fed operation are effective to overcome the difficult which traditional composting cannot applied successfully where high moisture vegetable wastes in more excess of flower wastes, such as Dianchi coastal.
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Sun, Xiang-Ping; Li, Guo-Xue; Xiao, Ai-Ping; Shi, Hong; Wang, Yi-Ming; Li, Yang-Yang
2014-09-01
Using pig manure and corn straw as raw materials for high-temperature composting, setting three different treat- ments: C/N 15, C/N 25, and C/N 35. Composting period is 120 days, which contains 30 days for ventilation cycle by forced continuous ventilation. Sampled on 0, 22, 30, 60, 90, 120th days, they were analyzed by elemental analysis and IR spectroscopy to study effect of different lignin content on compost humic acid (HA) composition and molecular structure. The results showed that the change in composting humic acid C focused on the first 30 days, while after composting, the O/C of compost HA increased, H/C decreased, and N content increased. Low C/N (15) and higher C/N ratio (35) had higher degree of oxidation than the C/N 25 in compost HA. FTIR indicated that the infrared spectrum shapes with different lignin content treatment are similar during the composting process, but the peak intensity is obviously different. Research results proved that the composting stage is more conducive to enhanced aromatic in compost HA. After composting, C/N 15 had less polysaccharide and fat ingredients and more aromatic structural components in compost HA, compared with C/N 25 and 35. In addition, compost HA of C/N 15 had higher degree of humification and its structure was more stable.
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Li, Sen; Luo, Xue Mei; Tu, Wei Guo; Fan, Hua; Gou, Xiao Lin; DU, Yu Long; Li, Ling; Wang, Qiong Yao
2017-04-18
To study the effects of nitrogen preserving agent (NPA) on composting process and nitrogen loss of Eichhornia crassipes, an aerobic composting was conducted for 35 days using four treatments. The NPA was prepared by mixing ferrous sulfate, humic acid sodium, and superphosphate (M:M:M=75:20:5). Four treatments were included with different mass ratios of NPA, including 0% (CK), 1% (PN1), 2% (PN2), and 3% (PN3). The physical and chemical properties, N fraction concentrations, ammonia volatilization, and N loss rates were measured and explored during composting process. The results showed that the pile temperature of NPA treatments were higher than that of CK in thermophillic period, however their water contents were significantly (P＜0.05) lower than that in CK in cooling period. At the end of composting, the concentrations of total nitrogen and organic nitrogen increased significantly in NPA treatments (P＜0.05), and their highest concentrations in the PN3 treatment were 16.3% and 13.2% higher than those in CK, respectively. The ammonia volatilization losses of PN1, PN2 and PN3 treatments were 25.9%, 31.5% and 42.4% lower than that of CK, respectively, however, their nitrogen fixation rates reached 31.3%, 40.7% and 72.2% respectively. Therefore, adding NPA could accelerate start-up speed, shorten composting time, and also could effectively reduce ammonia volatilizations and nitrogen loss in the composting process of E. crassipes. Therefore, PN3 showed the best effects of nitrogen preserving.
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Improvement of home composting process of food waste using different minerals.
Margaritis, M; Psarras, K; Panaretou, V; Thanos, A G; Malamis, D; Sotiropoulos, A
2018-03-01
This article presents the experimental study of the process of composting in a prototype home-scale system with a special focus on process improvement by using different additives (i.e. woodchips, perlite, vermiculite and zeolite). The interventions with different bulking agents were realized through composting cycles using substrates with 10% additives in specific mixtures of kitchen waste materials. The pre-selected proportion of the mixtures examined was 3:1:1 in cellulosic:proteins:carbohydrates, in order to achieve an initial C/N ratio equal to 30. The control of the initial properties of the examined substrates aimed at the consequent improvement of the properties of the final product (compost). The results indicated that composting process was enhanced with the use of additives and especially the case of zeolite and perlite provided the best results, in terms of efficient temperature evolution (>55 °C for 4 consecutive days). Carbon to nitrogen ratios decreased by 40% from the initial values for the reactors were minerals were added, while for the bioreactor tested with woodchips the reduction was slight, showing slowest degradation rate. Moisture content of produced compost varied within the range of 55-64% d.m., while nutrient content (K, Na, Ca, Mg) was in accordance with the limit values reported in literature. Finally, the composts obtained, exhibited a satisfactory degree of maturity, fulfilling the criterion related to the absence of phytotoxic compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Yu, Zhen; Tang, Jia; Liao, Hanpeng; Liu, Xiaoming; Zhou, Puxiong; Chen, Zhi; Rensing, Christopher; Zhou, Shungui
2018-06-07
The application of conventional thermophilic composting (TC) is limited by poor efficiency. Newly-developed hyperthermophilic composting (HTC) is expected to overcome this shortcoming. However, the characterization of microbial communities associated with HTC remains unclear. Here, we compared the performance of HTC and TC in a full-scale sludge composting plant, and found that HTC running at the hyperthermophilic and thermophilic phases for 21 days, led to higher composting efficiency and techno-economic advantages over TC. Results of high-throughput sequencing showed drastic changes in the microbial community during HTC. Thermaceae (35.5-41.7%) was the predominant family in the hyperthermophilic phase, while the thermophilic phase was dominated by both Thermaceae (28.0-53.3%) and Thermoactinomycetaceae (29.9-36.1%). The change of microbial community could be the cause of continuous high temperature in HTC, and thus improve composting efficiency by accelerating the maturation process. This work has provided theoretical and practical guidance for managing sewage sludge by HTC. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Improved composting of poultry feces via supplementation with ammonia oxidizing archaea.
Xie, Kaizhi; Jia, Xiaoshan; Xu, Peizhi; Huang, Xu; Gu, Wenjie; Zhang, Fabao; Yang, Shaohai; Tang, Shuanhu
2012-09-01
Ammonia-oxidizing archaea (AOA) play an important role in the oxidation of ammonia. However, the participation of AOA in the composting process has not been established. The addition of AOA to a compost mix was able to speed up both the onset of the hyperthermic phase and the composting time. The composition of the microflora and the relative abundance were determined by using denaturing gradient gel electrophoresis and quantitative real-time PCR, based on the presence of the archaeal amoA genes. The amplicon profiles allowed some of the major AOA species present in the final compost to be identified, and their relative abundance to be estimated from their amplification intensity. The lower pH during the lower temperature phase of compost served to enhance the nitrogen content of the final compost. The addition of AOA resulted in the expanding diversity of microflora species than that of the natural colonization. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.
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Fate and Effect of Antibiotics in Beef and Dairy Manure during Static and Turned Composting.
Ray, Partha; Chen, Chaoqi; Knowlton, Katharine F; Pruden, Amy; Xia, Kang
2017-01-01
Manure composting has general benefits for production of soil amendment, but the effects of composting on antibiotic persistence and effects of antibiotics on the composting process are not well-characterized, especially for antibiotics commonly used in dairy cattle. This study provides a comprehensive, head-to-head, replicated comparison of the effect of static and turned composting on typical antibiotics used in beef and dairy cattle in their actual excreted form and corresponding influence on composting efficacy. Manure from steers (with or without chlortetracycline, sulfamethazine, and tylosin feeding) and dairy cows (with or without pirlimycin and cephapirin administration) were composted at small scale (wet mass: 20-22 kg) in triplicate under static and turned conditions adapted to represent US Food and Drug Administration guidelines. Thermophilic temperature (>55°C) was attained and maintained for 3 d in all composts, with no measureable effect of compost method on the pattern, rate, or extent of disappearance of the antibiotics examined, except tylosin. Disappearance of all antibiotics, except pirlimycin, followed bi-phasic first-order kinetics. However, individual antibiotics displayed different fate patterns in response to the treatments. Reduction in concentration of chlortetracycline (71-84%) and tetracycline (66-72%) was substantial, while near-complete removal of sulfamethazine (97-98%) and pirlimycin (100%) was achieved. Tylosin removal during composting was relatively poor. Both static and turned composting were generally effective for reducing most beef and dairy antibiotic residuals excreted in manure, with no apparent negative impact of antibiotics on the composting process, but with some antibiotics apparently more recalcitrant than others. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
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Sun, Wei; Huang, Guo H; Zeng, Guangming; Qin, Xiaosheng; Yu, Hui
2011-03-01
It is widely known that variation of the C/N ratio is dependent on many state variables during composting processes. This study attempted to develop a genetic algorithm aided stepwise cluster analysis (GASCA) method to describe the nonlinear relationships between the selected state variables and the C/N ratio in food waste composting. The experimental data from six bench-scale composting reactors were used to demonstrate the applicability of GASCA. Within the GASCA framework, GA searched optimal sets of both specified state variables and SCA's internal parameters; SCA established statistical nonlinear relationships between state variables and the C/N ratio; to avoid unnecessary and time-consuming calculation, a proxy table was introduced to save around 70% computational efforts. The obtained GASCA cluster trees had smaller sizes and higher prediction accuracy than the conventional SCA trees. Based on the optimal GASCA tree, the effects of the GA-selected state variables on the C/N ratio were ranged in a descending order as: NH₄+-N concentration>Moisture content>Ash Content>Mean Temperature>Mesophilic bacteria biomass. Such a rank implied that the variation of ammonium nitrogen concentration, the associated temperature and the moisture conditions, the total loss of both organic matters and available mineral constituents, and the mesophilic bacteria activity, were critical factors affecting the C/N ratio during the investigated food waste composting. This first application of GASCA to composting modelling indicated that more direct search algorithms could be coupled with SCA or other multivariate analysis methods to analyze complicated relationships during composting and many other environmental processes. Copyright © 2010 Elsevier B.V. All rights reserved.
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Greenhouse gas emissions from home composting in practice.
Ermolaev, Evgheni; Sundberg, Cecilia; Pell, Mikael; Jönsson, Håkan
2014-01-01
In Sweden, 16% of all biologically treated food waste is home composted. Emissions of the greenhouse gases CH4 and N2O and emissions of NH3 from home composts were measured and factors affecting these emissions were examined. Gas and substrate in the compost bins were sampled and the composting conditions assessed 13 times during a 1-year period in 18 home composts managed by the home owners. The influence of process parameters and management factors was evaluated by regression analysis. The mean CH4 and N2O concentration was 28.1 and 5.46 ppm (v/v), respectively, above the ambient level and the CH4:CO2 and N2O:CO2 ratio was 0.38% and 0.15%, respectively (median values 0.04% and 0.07%, respectively). The home composts emitted less CH4 than large-scale composts, but similar amounts of N2O. Overall NH3 concentrations were low. Increasing the temperature, moisture content, mixing frequency and amount of added waste all increased CH4 emissions. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Economic feasibility of irradiation-composting plant of sewage sludge
NASA Astrophysics Data System (ADS)
Hashimoto, S.; Nishimura, K.; Machi, S.
Design and cost analysis were made for a sewage sludge treatment plant (capacity 25 - 200 ton sludge/day) with an electron accelerator. Dewatered sludge is spreaded on a rolling drum through a flat nozzle and disinfected by electron irradiation with a dose of 5 kGy. Composting of the irradiated sludge is also made at the optimum temperature for 3 days. The accelerating voltage of electron and capacity of the accelerator are 1.5 MV and 15 kW, respectively. Total volume of the fermentor is about one third of that of conventional composting process because the irradiation makes the time of composting shorter. The cost of sludge treatment is almost the same as that of conventional method.
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Oviedo-Ocaña, E R; Torres-Lozada, P; Marmolejo-Rebellon, L F; Hoyos, L V; Gonzales, S; Barrena, R; Komilis, D; Sanchez, A
2015-10-01
Stability and maturity are important criteria to guarantee the quality of a compost that is applied to agriculture or used as amendment in degraded soils. Although different techniques exist to evaluate stability and maturity, the application of laboratory tests in municipalities in developing countries can be limited due to cost and application complexities. In the composting facilities of such places, some classical low cost on-site tests to monitor the composting process are usually implemented; however, such tests do not necessarily clearly identify conditions of stability and maturity. In this article, we have applied and compared results of stability and maturity tests that can be easily employed on site (i.e. temperature, pH, moisture, electrical conductivity [EC], odor and color), and of tests that require more complex laboratory techniques (volatile solids, C/N ratio, self-heating, respirometric index, germination index [GI]). The evaluation of the above was performed in the field scale using 2 piles of biowaste applied compost. The monitoring period was from day 70 to day 190 of the process. Results showed that the low-cost tests traditionally employed to monitor the composting process on-site, such as temperature, color and moisture, do not provide consistent determinations with the more complex laboratory tests used to assess stability (e.g. respiration index, self-heating, volatile solids). In the case of maturity tests (GI, pH, EC), both the on-site tests (pH, EC) and the laboratory test (GI) provided consistent results. Although, stability was indicated for most of the samples, the maturity tests indicated that products were consistently immature. Thus, a stable product is not necessarily mature. Conclusively, the decision on the quality of the compost in the installations located in developing countries requires the simultaneous use of a combination of tests that are performed both in the laboratory and on-site. Copyright © 2015 Elsevier Ltd. All rights reserved.
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The Utilization of Banana Peel in the Fermentation Liquid in Food Waste Composting
NASA Astrophysics Data System (ADS)
Kadir, A. A.; Rahman, N. A.; Azhari, N. W.
2016-07-01
Municipal solid waste in Malaysia contains a high amount of organic matters, particularly food waste. Food waste represents almost 60% from the total municipal solid waste disposed in the landfill. Food waste can be converted into useful materials such as compost. However, source separation of food waste for recycling is not commonly practiced in Malaysia due to various constraints. These constraints include low awareness among the waste generators and low demand of the products produced from the food waste such as composts. Composting is one of the alternatives that can be used in food waste disposal from Makanan Ringan Mas. The aim of the study is to convert food waste generated from Makanan Ringan Mas which is a medium sale industry located at Parit Kuari Darat, Batu Pahat by using composting method. The parameters which include temperature, pH value, NPK (Nitrogen, Phosphorus, Potassium) values has been examined. Banana peel is being used as the fermentation liquid whilst soil and coconut husk were used as the composting medium. Based on the results during the composting process, most of the pH value in each reactor is above 5 and approximately at neutral. This shown that the microbial respiration in the well controlled composting reactor was inhibited and had approached the mature phase. On the other hand, during the period of composting, the overall temperature range from 25 °C to 47 °C which shown the active phase for composting will occoured. As for NPK content Nitrogen value range is 35325 mg/L to 78775 mg/L, Phosphorus, 195.83 mg/L to 471 mg/L and potassium is 422.3 mg/L to 2046 mg/L which is sufficient to use for agricultural purpose. The comparison was made with available organic compost in the market and only showed slightly difference. Nevertheless, in comparison with common fertilizer, the NPK value of organic compost are considerably very low.
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Zainudin, Mohd Huzairi Mohd; Ramli, Norhayati; Hassan, Mohd Ali; Shirai, Yoshihito; Tashiro, Kosuke; Sakai, Kenji; Tashiro, Yukihiro
2017-06-01
A recently developed rapid co-composting of oil palm empty fruit bunch (OPEFB) and palm oil mill effluent (POME) anaerobic sludge is beginning to attract attention from the palm oil industry in managing the disposal of these wastes. However, a deeper understanding of microbial diversity is required for the sustainable practice of the co-compositing process. In this study, an in-depth assessment of bacterial community succession at different stages of the pilot scale co-composting of OPEFB-POME anaerobic sludge was performed using 454-pyrosequencing, which was then correlated with the changes of physicochemical properties including temperature, oxygen level and moisture content. Approximately 58,122 of 16S rRNA gene amplicons with more than 500 operational taxonomy units (OTUs) were obtained. Alpha diversity and principal component analysis (PCoA) indicated that bacterial diversity and distributions were most influenced by the physicochemical properties of the co-composting stages, which showed remarkable shifts of dominant species throughout the process. Species related to Devosia yakushimensis and Desemzia incerta are shown to emerge as dominant bacteria in the thermophilic stage, while Planococcus rifietoensis correlated best with the later stage of co-composting. This study proved the bacterial community shifts in the co-composting stages corresponded with the changes of the physicochemical properties, and may, therefore, be useful in monitoring the progress of co-composting and compost maturity.
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Stanford, K; Hao, X; Xu, S; McAllister, T A; Larney, F; Leonard, J J
2009-10-01
As residual bones in mortality compost negatively impact subsequent tillage, two studies were performed. For the first study, windrows of mature cattle or calves were placed on a base of barley straw and covered with beef manure. Windrows were divided into two sections and turned at 3-month intervals. Approximately 5000 kg of finished compost per windrow was passed through a 6mm trommel screen, with bones collected and weighed. Bone weight was 0.66% of mature cattle compost and 0.38% of calf compost on a dry matter basis, but did not differ after adjustment for weights of compost ingredients. In a subsequent study, four windrows were constructed containing mortalities, straw and beef manure (STATC) or straw, manure and slaughter waste (STATW). Also, straw, beef manure and slaughter waste was added to an 850 L rolling drum composter (DRUMW). Fresh bovine long-bones from calves were collected, weighed and embedded in the compost. Bones were retrieved and weighed when windrows were turned, or with DRUMW, after 8 weeks. Temperatures achieved followed the order STATW>STATC>DRUMW (p<0.05). Rate of bone disappearance followed a pattern identical to temperature, with the weight of bones in STATW declining by 53.7% during 7 weeks of composting. For STATC, temperatures were uniform over three composting periods, but bone disappearance was improved (p<0.05) when compost dry matter was lower (46%), as compared to 58%. Using a ratio of five parts manure to one part mortalities, results of this study demonstrated that residual bone was <1% of cured cattle compost and may be reduced by maintaining a high compost temperature and moisture content.
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Water state changes during the composting of kitchen waste.
Shen, Dong-Sheng; Yang, Yu-Qiang; Huang, Huan-Lin; Hu, Li-Fang; Long, Yu-Yang
2015-04-01
Changes in water states during the composting of kitchen waste were determined. Three experiments, R(55), R(60), and R(65), with different initial moisture contents, 55%, 60%, and 65%, respectively, were performed. Three water states, entrapped water (EW), capillary water (CW), and multiple-molecular-layer water (MMLW), were monitored during the experiments. Changes only occurred with the EW and CW during the composting process. The percentage of EW increased, and the percentage of CW decreased as the composting process progressed. The R(60) experiment performed better than the other experiments according to changes in the temperature and carbon-to-nitrogen ratio (C/N). The percentage of EW correlated well (P<0.05) with the dissolved organic carbon content (DOC), electrical conductivity (EC), pH, and C/N, and was affected by the hemicellulose and cellulose contents. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Composting of sewage sludge with solid fraction of digested pulp from agricultural biogas plant
NASA Astrophysics Data System (ADS)
Czekała, Wojciech; Dach, Jacek; Przybył, Jacek; Mazurwiekiwcz, Jakub; Janczak, Damian; Lewicki, Andrzej; Smurzyńska, Anna; Kozłowski, Kamil
2018-02-01
Sewage sludge management is an important element of environmental protection. Composting and anaerobic digestion are the biological conversion methods for sewage sludge management. Mass and volume reduction is a result of a properly composted process. Solid fraction of digested pulp can be use as co-substrate, because it is good structural material. The aim of the study was to determine the possibility of composting sewage sludge with a solid fraction of digestate. The compost mix consisted of 25 kilograms of sewage sludge and 20 kilograms solid fraction of digestate in fresh mass. The experiment was carried out in laboratory conditions. Bioreactors of 165 dm3 volume were used. The experiment included two stages. Stage I took place in bioreactors and lasted until the cooling phase of the compost was complete. Stage II included compost maturation for a period of eight months (to 287 day of composting). The reduction of mass obtained at the end of Stage I amounted 30.2%. At the end of Stage II, it was 86.7% relative to the initial weight of the compost. The maximum value of temperature was 75.1°C. Studies have shown that sludge with a solid fraction of digestate can be a suitable substrate for composting with sewage sludge.
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Quality assessment of compost prepared with municipal solid waste
NASA Astrophysics Data System (ADS)
Jodar, J. R.; Ramos, N.; Carreira, J. A.; Pacheco, R.; Fernández-Hernández, A.
2017-11-01
One way that helps maintain the sustainability of agro-ecosystems land is the application of compost from municipal solid waste as fertilizer, because it can recover the nutrients contained in them, minimizing the negative impact on the environment. Composting as a method for preparing organic fertilizers and amendments is economically and ecologically sound and may well represent an acceptable solution for disposing of municipal solid waste. In the present work, the quality of compost is studied made from municipal solid waste; the content of mineral nutrients: potassium, calcium, magnesium, sodium, zinc, manganese, cupper, iron, nickel, chromium and lead has been investigated. The objective was to evaluate the changes in mineral nutrient concentration during the composting process. The compost was prepared in a pilot-plant using the turning-pile system. Temperature was used as a monitoring parameter to follow the composting progress, which underwent the typical trend of municipal solid waste composting mixtures. The results showed a similar evolution on the content of mineral nutrients of the mixture of municipal solid waste. This evolution originated in a mature compost (end sample) with an adequate content of mineral elements and physical-chemical characteristics for its use in agriculture. So, the use of compost of municipal solid waste represents an important tool for fertilization requirements for its use in agriculture.
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Wang, Cheng; Dong, Da; Strong, P J; Zhu, Weijing; Ma, Zhuang; Qin, Yong; Wu, Weixiang
2017-08-16
Animal manure is a reservoir of antibiotic resistance genes (ARGs) that pose a potential health risk globally, especially for resistance to the antibiotics commonly used in livestock production (such as tetracycline, sulfonamide, and fluoroquinolone). Currently, the effects of biological treatment (composting) on the transcriptional response of manure ARGs and their microbial hosts are not well characterized. Composting is a dynamic process that consists of four distinct phases that are distinguished by the temperature resulting from microbial activity, namely the mesophilic, thermophilic, cooling, and maturing phases. In this study, changes of resistome expression were determined and related to active microbiome profiles during the dynamic composting process. This was achieved by integrating metagenomic and time series metatranscriptomic data for the evolving microbial community during composting. Composting noticeably reduced the aggregated expression level of the manure resistome, which primarily consisted of genes encoding for tetracycline, vancomycin, fluoroquinolone, beta-lactam, and aminoglycoside resistance, as well as efflux pumps. Furthermore, a varied transcriptional response of resistome to composting at the ARG levels was highlighted. The expression of tetracycline resistance genes (tetM-tetW-tetO-tetS) decreased during composting, where distinctive shifts in the four phases of composting were related to variations in antibiotic concentration. Composting had no effect on the expression of sulfonamide and fluoroquinolone resistance genes, which increased slightly during the thermophilic phase and then decreased to initial levels. As indigenous populations switched greatly throughout the dynamic composting, the core resistome persisted and their reservoir hosts' composition was significantly correlated with dynamic active microbial phylogenetic structure. Hosts for sulfonamide and fuoroquinolone resistance genes changed notably in phylognetic structure and underwent an initial increase and then a decrease in abundance. By contrast, hosts for tetracycline resistance genes (tetM-tetW-tetO-tetS) exhibited a constant decline through time. The transcriptional patterns of a core resistome over the course of composting were identified, and microbial phylogeny was the key determinant in defining the varied transcriptional response of resistome to this dynamic biological process. This research demonstrated the benefits of composting for manure treatment. It reduced the risk of emerging environmental contaminants such as tetracyclines, tetracycline resistance genes, and clinically relevant pathogens carrying ARGs, as well as RNA viruses and bacteriophages.
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A compost bin for handling privy wastes: its fabrication and use
R.E. Leonard; S.C. Fay
1978-01-01
A 24-ft3 (6.8-m3) fiberglass bin was constructed and tested for its effectiveness in composting privy wastes. A mixture of ground hardwood bark and raw sewage was used for composting. Temperatures in excess of 60°C for 36 hours were produced in the bin by aerobic, thermophilic composting. This temperature is...
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Musioł, Marta; Sikorska, Wanda; Adamus, Grazyna; Janeczek, Henryk; Richert, Jozef; Malinowski, Rafal; Jiang, Guozhan; Kowalczuk, Marek
2016-06-01
This paper presents a forensic engineering study on the biodegradation behaviour of prototype packaging thermoformed from PLA-extruded film and plain PLA film under industrial composting conditions. Hydrolytic degradation in water was conducted for reference. The effects of composting duration on changes in molar mass, glass transition temperature and degree of crystallinity of the polymeric material were monitored using gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). The chemical structure of water soluble degradation products of the polymeric material was determined using nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). The results show that the biodegradation process is less dependent on the thermoforming process of PLA and more dependent on the composting/degradation conditions that are applied. The increase in the dispersity index, leading to the bimodal molar mass distribution profile, suggests an autocatalytic hydrolysis effect at the early stage of the composting process, during which the bulk hydrolysis mechanism dominantly operates. Both the prototype PLA-packaging and PLA rigid film samples were shown to have a gradual increase in opacity due to an increase in the degree of crystallinity. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Low-Temperature Effects on the Design and Performance of Composting of Explosives-Contaminated Soils
1991-03-01
7 7. Aerated bins used in field composting tests on dairy manure ............................. 10 8. Typical temperature developed...during bin compostiag of dairy manure under conditions of constant airflow and optimum moisture ................. 10 9. Effect of agitation on the...temperature profile during bin composting of dairy manure
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NASA Astrophysics Data System (ADS)
Pettersson, K. A.
1981-03-01
The conditions for the construction of an economical plant of wet composting are considered. Eleven cu. m. oil were saved when 90,000 SEK were invested. By means of a heat pump the temperature was increased to 600 C. The properties of the manure are improved which simplifies the subsequent handling.
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Treatment of smuggled cigarette tobacco by composting process in facultative reactors.
Zittel, Rosimara; Pinto da Silva, Cleber; Domingues, Cinthia Eloise; de Oliveira Stremel, Tatiana Roselena; de Almeida, Thiago Eduardo; Vieira Damiani, Gislaine; Xavier de Campos, Sandro
2018-01-01
This paper presents a study on the degradation of smuggled cigarette tobacco combined with domestic organic waste and sawdust or wood chips, using facultative reactor. Four reactors with different amounts of residue were assembled. For the study of the quality of the compost obtained, physicochemical, phytotoxicity and microbiological analyses were carried out. The mixture with wood chips presented the best temperature conditions and pH variation optimizing the degradation. The final germination index (GI) values of all treatments were above the recommended GI value (50%) and the final C/N ratio between 8 and 13 indicated a mature compost. The concentration of metals under study was below the limit allowed for the commercialization. The composting carried out in all facultative reactors provided ideal conditions for the total sterilization of the final compost. Therefore, the treatment of smuggled cigarettes through facultative reactors was efficient to produce stable and mature compost. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Odour in composting processes at pilot scale: monitoring and biofiltration.
Gutiérrez, M C; Serrano, A; Martín, M A; Chica, A F
2014-08-01
Although odour emissions associated with the composting process, especially during the hydrolytic stage, are widely known, their impact on surrounding areas is not easily quantifiable, For this reason, odour emissions during the first stage ofcomposting were evaluated by dynamic olfactometry at pilot scale in order to obtain results which can be extrapolated to industrial facilities. The composting was carried out in a commercial dynamic respirometer equipped with two biofilters at pilot scale filled with prunings (Populus) and mature compost obtained from the organic fraction of municipal solid waste. Given that the highest odour emissions occur in the first stage of the composting process, this stage was carried out in a closed system to better control the odour emissions, whose maximum value was estimated to be 2.78 ouF S-1 during the experiments. Odour concentration, the dynamic respiration index and temperature showed the same evolution during composting, thus indicating that odour could be a key variable in the monitoring process. Other variables such as total organic carbon (CTOC) and pH were also found to be significant in this study due to their influence over odour emissions. The efficiency of the biofilters (empty bed residence time of 86 s) was determined by quantifying the odour emissions at the inlet and outlet of both biofilters. The moisture content in the biofilters was found to be an important variable for improving odour removal efficiency, while the minimum moisture percentage to obtain successful results was found to be 55% (odour removal efficiency of 95%).
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Inoculation of Scytalidium thermophilum in Button Mushroom Compost and Its Effect on Yield.
Straatsma, G; Olijnsma, T W; Gerrits, J P; Amsing, J G; Op Den Camp, H J; Van Griensven, L J
1994-09-01
Scytalidium thermophilum isolates in culture, as well as the endogenous strain(s) in mushroom compost, were inactivated at 70 degrees C. This temperature was used to pasteurize composts for experiments. Of nine thermophilic fungal species, only S. thermophilum and Myriococcum thermophilum grew well on pasteurized compost in test tubes. The effect of both species on the crop yield of Agaricus bisporus mushrooms was studied. In solid-state fermentation rooms called tunnels, compost was pasteurized and inoculated. After incubation, the inoculated organisms were reisolated and counted, showing their successful colonization. The yield of mushrooms on inoculated composts was almost twice that on the pasteurized control. This result demonstrates the effectiveness of S. thermophilum in compost preparation. Inoculation is not necessary for traditional compost preparation. Naturally occurring strains of S. thermophilum, present in ingredients, readily colonize compost during preparation. Inoculation may be vital if compost is pretreated at a high temperature in tunnels. This finding is of relevance for the environmentally controlled production of high-yielding compost.
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Inoculation of Scytalidium thermophilum in Button Mushroom Compost and Its Effect on Yield
Straatsma, Gerben; Olijnsma, Tineke W.; Gerrits, Jan P. G.; Amsing, Jos G. M.; Op Den Camp, Huub J. M.; Van Griensven, Leo J. L. D.
1994-01-01
Scytalidium thermophilum isolates in culture, as well as the endogenous strain(s) in mushroom compost, were inactivated at 70°C. This temperature was used to pasteurize composts for experiments. Of nine thermophilic fungal species, only S. thermophilum and Myriococcum thermophilum grew well on pasteurized compost in test tubes. The effect of both species on the crop yield of Agaricus bisporus mushrooms was studied. In solid-state fermentation rooms called tunnels, compost was pasteurized and inoculated. After incubation, the inoculated organisms were reisolated and counted, showing their successful colonization. The yield of mushrooms on inoculated composts was almost twice that on the pasteurized control. This result demonstrates the effectiveness of S. thermophilum in compost preparation. Inoculation is not necessary for traditional compost preparation. Naturally occurring strains of S. thermophilum, present in ingredients, readily colonize compost during preparation. Inoculation may be vital if compost is pretreated at a high temperature in tunnels. This finding is of relevance for the environmentally controlled production of high-yielding compost. PMID:16349366
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Greenhouse gas emission from covered windrow composting with controlled ventilation.
Ermolaev, Evgheni; Pell, Mikael; Smårs, Sven; Sundberg, Cecilia; Jönsson, Håkan
2012-02-01
Data on greenhouse gas (GHG) emissions from full-scale composting of municipal solid waste, investigating the effects of process temperature and aeration combinations, is scarce. Oxygen availability affects the composition of gases emitted during composting. In the present study, two experiments with three covered windrows were set up, treating a mixture of source separated biodegradable municipal solid waste (MSW) fractions from Uppsala, Sweden, and structural amendment (woodchips, garden waste and re-used compost) in the volume proportion 1:2. The effects of different aeration and temperature settings on the emission of methane (CH(4)), nitrous oxide (N(2)O) and carbon dioxide (CO(2)) during windrow composting with forced aeration following three different control schemes were studied. For one windrow, the controller was set to keep the temperature below 40 °C until the pH increased, another windrow had minimal aeration at the beginning of the process and the third one had constant aeration. In the first experiment, CH(4) concentrations (CH(4):CO(2) ratio) increased, from around 0.1% initially to between 1 and 2% in all windrows. In the second experiment, the initial concentrations of CH(4) displayed similar patterns of increase between windrows until day 12, when concentration peaked at 3 and 6%, respectively, in two of the windrows. In general, the N(2)O fluxes remained low (0.46 ± 0.02 ppm) in the experiments and were two to three times the ambient concentrations. In conclusion, the emissions of CH(4) and N(2)O were low regardless of the amount of ventilation. The data indicates a need to perform longer experiments in order to observe further emission dynamics.
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Humic acid batteries derived from vermicomposts at different C/N ratios
NASA Astrophysics Data System (ADS)
Shamsuddin, R. M.; Borhan, A.; Lim, W. K.
2017-06-01
Humic acid is a known fertilizer derived from decomposed organic matters. Organic wastes are normally landfilled for disposal which had contributed negatively to the environment. From waste-to-wealth perspective, such wastes are potential precursors for compost fertilizers. When worms are added into a composting process, the process is termed as vermicomposting. In this work, humic acid from vermicompost derived from campus green wastes was developed into a battery. This adds value proposition to compost instead of being traditionally used solely as soil improver. This research work aimed to study the correlation between electrical potential generated by humic acid at different Carbon to Nitrogen (C/N) ratios of vermicompost at 20, 25, 30 and 35. The temperature and pH profiles of composting revealed that the compost was ready after 55 days. The humic acid was extracted from compost via alkaline extraction followed by precipitation in a strong acid. The extracted humic acid together with other additives were packed into a compartment and termed as vermibattery. Another set of battery running only on the additives was also prepared as a control. The net voltage produced by a single vermibattery cell with Zn and PbO electrodes was in the range of 0.31 to 0.44 V with compost at C/N ratio of 30 gave the highest voltage. The battery can be connected in series to increase the voltage generation. Quality assessment on the compost revealed that the final carbon content is between 16 to 23 wt%, nitrogen content of 0.4 to 0.5 wt%, humic acid yield of 0.7 to 1.5 wt% and final compost mass reduction of 10 to 35 wt%. Composting campus green wastes carries multi-fold benefits of reducing labour requirement, generating fertilizer for campus greenery and green battery construction.
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Performance of five Montreal West Island home composters.
Adhikari, Bijaya K; Trémier, Anne; Barrington, Suzelle
2012-01-01
Even if home composting can eliminate municipal organic waste collection, handling and treatment costs, its compost quality requires investigation outside the laboratory. A study was thus conducted to evaluate the influence of the following management practices on the compost quality produced by five backyards home composters in Montreal West Island from June to October 2010: the type and backyard location of the home composter (HC), and the rate and type of organic waste (OW) fed into the home composter. The parameters monitored were compost temperature and final characteristics including trace elements and pathogens. For all HC compost, maximum but not necessarily thermophilic temperatures were highly probable within one week of adding more than 10 kg of OW composed of equal volumes of food waste (FW) and yard trimmings (YT). Top and bottom HC perforations enhanced convective aeration but concentrated OW decomposition within the bottom layer. Fed an equal volume of FW and YT, the final HC compost had a dry and organic matter content exceeding 30%, and 50%, respectively, and a total nitrogen, phosphorous and potassium level of 2, 1 and 3% on a dry matter basis, representing a good quality soil amendment. Clean OW feeding resulted in compost respecting Canadian and European regulations for Escherichia coli and Salmonella, irrespective of the temperature regime. For trace elements, regulatory limits may be exceeded when the home composter is fed ashes and soil. Homeowners must also be careful when applying pesticides to their lawns and gardens and then feeding the residues to the home composter.
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A stepwise-cluster microbial biomass inference model in food waste composting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun Wei; Huang, Guo H., E-mail: huangg@iseis.or; Chinese Research Academy of Environmental Science, North China Electric Power University, Beijing 100012-102206
2009-12-15
A stepwise-cluster microbial biomass inference (SMI) model was developed through introducing stepwise-cluster analysis (SCA) into composting process modeling to tackle the nonlinear relationships among state variables and microbial activities. The essence of SCA is to form a classification tree based on a series of cutting or mergence processes according to given statistical criteria. Eight runs of designed experiments in bench-scale reactors in a laboratory were constructed to demonstrate the feasibility of the proposed method. The results indicated that SMI could help establish a statistical relationship between state variables and composting microbial characteristics, where discrete and nonlinear complexities exist. Significance levelsmore » of cutting/merging were provided such that the accuracies of the developed forecasting trees were controllable. Through an attempted definition of input effects on the output in SMI, the effects of the state variables on thermophilic bacteria were ranged in a descending order as: Time (day) > moisture content (%) > ash content (%, dry) > Lower Temperature (deg. C) > pH > NH{sub 4}{sup +}-N (mg/Kg, dry) > Total N (%, dry) > Total C (%, dry); the effects on mesophilic bacteria were ordered as: Time > Upper Temperature (deg. C) > Total N > moisture content > NH{sub 4}{sup +}-N > Total C > pH. This study made the first attempt in applying SCA to mapping the nonlinear and discrete relationships in composting processes.« less
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NASA Technical Reports Server (NTRS)
Hogan, John; Kang, Sukwon; Cavazzoni, Jim; Levri, Julie; Finn, Cory; Luna, Bernadette (Technical Monitor)
2000-01-01
The objective of this study is to compare incineration and composting in a Mars-based advanced life support (ALS) system. The variables explored include waste pre-processing requirements, reactor sizing and buffer capacities. The study incorporates detailed mathematical models of biomass production and waste processing into an existing dynamic ALS system model. The ALS system and incineration models (written in MATLAB/SIMULINK(c)) were developed at the NASA Ames Research Center. The composting process is modeled using first order kinetics, with different degradation rates for individual waste components (carbohydrates, proteins, fats, cellulose and lignin). The biomass waste streams are generated using modified "Eneray Cascade" crop models, which use light- and dark-cycle temperatures, irradiance, photoperiod, [CO2], planting density, and relative humidity as model inputs. The study also includes an evaluation of equivalent system mass (ESM).
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Giuliana, D'Imporzano; Fabrizio, Adani
2007-02-01
This study aims to establish the contribution of the water soluble and water insoluble organic fractions to total oxygen uptake rate during high rate composting process of a mixture of organic fraction of municipal solid waste and lignocellulosic material. This mixture was composted using a 20 l self-heating pilot scale composter for 250 h. The composter was fully equipped to record both the biomass-temperature and oxygen uptake rate. Representative compost samples were taken at 0, 70, 100, 110, 160, and 250 h from starting time. Compost samples were fractionated in water soluble and water insoluble fractions. The water soluble fraction was then fractionated in hydrophilic, hydrophobic, and neutral hydrophobic fractions. Each fraction was then studied using quantitative (total organic carbon) and qualitative analysis (diffuse reflectance infrared spectroscopy and biodegradability test). Oxygen uptake rates were high during the initial stages of the process due to rapid degradation of the soluble degradable organic fraction (hydrophilic plus hydrophobic fractions). Once this fraction was depleted, polymer hydrolysis accounted for most of the oxygen uptake rate. Finally, oxygen uptake rate could be modeled using a two term kinetic. The first term provides the oxygen uptake rate resulting from the microbial growth kinetic type on easily available, no-limiting substrate (soluble fraction), while the second term considers the oxygen uptake rate caused by the degradation of substrate produced by polymer hydrolysis.
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Risks to farm animals from pathogens in composted catering waste containing meat.
Gale, P
2004-07-17
Uncooked meat may contain animal pathogens, including bovine spongiform encephalopathy, foot-and-mouth disease virus, African swine fever virus and classical swine fever virus, and to prevent outbreaks of these diseases in farm animals, the disposal of meat from catering waste is controlled under the Animal By-Products Regulations. This paper estimates the risks to farm animals of grazing land on to which compost, produced by the composting of catering waste containing meat, has been applied. The factors controlling the level of risk are the separation of the meat at source, the efficiency of the composting process, and the decay and dilution of the pathogens in soil. The net pathogen destruction by the composting process is determined largely by the degree of bypass, and to accommodate the possibility of large joints or even whole carcases being discarded uncooked to catering waste, a time/temperature condition of 60 degrees C for two days is recommended. Where data are lacking, worst-case assumptions have been applied. According to the model, classical swine fever virus constitutes the highest risk, but the assessment shows that a two-barrier composting approach, together with a two-month grazing ban, reduces the risk to one infection in pigs every 190 years in England and Wales. This work defined the operational conditions for the composting of catering waste as set out in the Animal By-Products Regulations 2003 (SI 1482).
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Arab, Golnaz; McCartney, Daryl
2017-10-01
Anaerobic digestion (AD) has gained a significant role in municipal solid waste management, but managing a high volume of digestate is one of the challenges with AD technology. One option is to mix digestate with fresh and/or stabilized organic waste and then feed to the composting process. In this study, the effect of co-composting anaerobic digestate (in different quantities) on a composting process was investigated. The digestate was prepared in a pilot-scale 500L high solids dry anaerobic digester and composting was completed in eight 25L reactors with different ratios of digestate to fresh feedstock from the organic fraction of municipal solid waste (OFMSW). The digestate constituted 0, 10, 20, 30, 40, 50, 75, or 100% (wet mass) of the feedstock. The co-composting experiment was conducted in two phases: active aeration and curing. Monitored parameters included: process temperature, aeration rate, oxygen concentration of the outlet gas, mass changes, total solids, organic matter, pH, and electrical conductivity. In addition, respirometry, C:N ratio, ammonium to nitrate ratio, and Solvita® tests were used to quantify stability and maturity end points. The results showed that the addition of digestate to the OFMSW increased composting reaction rates in all cases, with peak performance occurring within the ratio of 20-40% of digestate addition on a wet weight basis. Reactor performance may have been influenced by the high total ammonia nitrogen (TAN) levels in the digestate. Composting rates increased as TAN levels increased up to 5000 TAN mgkg -1 DM; however, TAN may have become inhibitory at higher levels. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
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Effect of semi-permeable cover system on the bacterial diversity during sewage sludge composting.
Robledo-Mahón, Tatiana; Aranda, Elisabet; Pesciaroli, Chiara; Rodríguez-Calvo, Alfonso; Silva-Castro, Gloria Andrea; González-López, Jesús; Calvo, Concepción
2018-06-01
Sewage sludge composting is a profitable process economically viable and environmentally friendly. In despite of there are several kind of composting types, the use of combined system of semipermeable cover film and aeration air-floor is widely developed at industrial scale. However, the knowledge of the linkages between microbial communities structure, enzyme activities and physico-chemical factors under these conditions it has been poorly explored. Thus, the aim of this study was to investigate the bacterial dynamic and community structure using next generation sequencing coupled to analyses of microbial enzymatic activity and culturable dependent techniques in a full-scale real composting plant. Sewage sludge composting process was conducted using a semi-permeable Gore-tex cover, in combination with an air-insufflation system. The highest values of enzymatic activities such as dehydrogenase, protease and arylsulphatase were detected in the first 5 days of composting; suggesting that during this period of time a greater degrading activity of organic matter took place. Culturable bacteria identified were in agreement with the bacteria found by massive sequencing technologies. The greatest bacterial diversity was detected between days 15 and 30, with Actinomycetales and Bacillales being the predominant orders at the beginning and end of the process. Bacillus was the most representative genus during all the process. A strong correlation between abiotic factors as total organic content and organic matter and enzymatic activities such as dehydrogenase, alkaline phosphatase, and ß-glucosidase activity was found. Bacterial diversity was strongly influenced by the stage of the process, community-structure change was concomitant with a temperature rise, rendering favorable conditions to stimulate microbial activity and facilitate the change in the microbial community linked to the degradation process. Moreover, results obtained confirmed that the use of semipermeable cover in the composting of sewage sludge allow a noticeable reduction in the process-time comparing to conventional open windrows. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Effect of temperature on bacterial species diversity in thermophilic solid-waste composting.
Strom, P F
1985-01-01
Continuously thermophilic composting was examined with a 4.5-liter reactor placed in an incubator maintained at representative temperatures. Feed was a mixture of dried table scraps and shredded newspaper wetted to 55% moisture. One run at 49 degrees C (run A) employed a 1:4 feed-to-compost ratio, while the other runs used a 10:1 ratio and were incubated at 50, 55, 60, or 65 degrees C. Due to self-heating, internal temperatures of the composting mass were 0 to 7 degrees C hotter than the incubator. Two full-scale composting plants (at Altoona, Pa., and Leicester, England) were also examined. Plate counts per gram (dry weight) on Trypticase soy broth (BBL Microbiology Systems) with 2% agar ranged from 0.7 X 10(9) to 5.3 X 10(9) for laboratory composting and 0.02 X 10(9) to 7.4 X 10(9) for field composting. Fifteen taxa were isolated, including 10 of genus Bacillus, which dominated all samples except that from run A. Species diversity decreased markedly in laboratory composting at 60 degrees C and above, but was similar for the three runs incubated at 49, 50, and 55 degrees C. The maximum desirable composting temperature based on species diversity is thus 60 degrees C, the same as that previously recommended based on measures of the rate of decomposition. PMID:4083885
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Ren, Xiaoya; Zeng, Guangming; Tang, Lin; Wang, Jingjing; Wan, Jia; Wang, Jiajia; Deng, Yaocheng; Liu, Yani; Peng, Bo
2018-02-01
Large numbers of organic pollutants (OPs), such as polycyclic aromatic hydrocarbons, pesticides and petroleum, are discharged into soil, posing a huge threat to natural environment. Traditional chemical and physical remediation technologies are either incompetent or expensive, and may cause secondary pollution. The technology of soil composting or use of compost as soil amendment can utilize quantities of active microbes to degrade OPs with the help of available nutrients in the compost matrix. It is highly cost-effective for soil remediation. On the one hand, compost incorporated into contaminated soil is capable of increasing the organic matter content, which improves the soil environment and stimulates the metabolically activity of microbial community. On the other hand, the organic matter in composts would increase the adsorption of OPs and affect their bioavailability, leading to decreased fraction available for microorganism-mediated degradation. Some advanced instrumental analytical approaches developed in recent years may be adopted to expound this process. Therefore, the study on bioavailability of OPs in soil is extremely important for the application of composting technology. This work will discuss the changes of physical and chemical properties of contaminated soils and the bioavailability of OPs by the adsorption of composting matrix. The characteristics of OPs, types and compositions of compost amendments, soil/compost ratio and compost distribution influence the bioavailability of OPs. In addition, the impact of composting factors (composting temperature, co-substrates and exogenous microorganisms) on the removal and bioavailability of OPs is also studied. Copyright © 2017 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Labrador, Juana; Gordillo, Judit; Ruiz, Trinidad; Albano, Eva; Moreno, Marta M.
2016-04-01
The biotransformation of the invasive water hyacinth (Eichhornia crassipes) by composting has been showed as a viable alternative to offset the economic cost of eliminating an invasive plant giving a value to the by-product; however, as result of the propagative plant capacity, it was necessary to check if the composting process could eliminate the germination seed rate. Despite the high temperatures and the biochemical biotransformation processes of the composting components, in the case of seed water hyacinth, with a recovery rate of 100%, damage was observed in some parts of the seed anatomy such as in the outer teguments; however, other parts of the seed coat and the endosperm maintained their integrity. A microscopic analysis revealed that the embryo was noticeable and this was supported by the rate of seed germination observed (3.5 ± 0.96%). The results indicate that the use of water hyacinth for compost production is not completely safe from an environmental perspective. Keywords: Eichhornia crassipes, water hyacinth, invasive plant, seed anatomy, seed germination rate, compost. References: Ruiz T., Martín de Rodrigo E., Lorenzo G., Albano E., Morán R., Sánchez J.M. 2008. The Water Hyacinth, Eichhornia crassipes: an invasive plant in the Guadiana River Basin (Spain). Aquatic Invasions Volume 3, Issue 1:42-53.
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Food Waste Composting Study from Makanan Ringan Mas
NASA Astrophysics Data System (ADS)
Kadir, A. A.; Ismail, S. N. M.; Jamaludin, S. N.
2016-07-01
The poor management of municipal solid waste in Malaysia has worsened over the years especially on food waste. Food waste represents almost 60% of the total municipal solid waste disposed in the landfill. Composting is one of low cost alternative method to dispose the food waste. This study is conducted to compost the food waste generation in Makanan Ringan Mas, which is a medium scale industry in Parit Kuari Darat due to the lack knowledge and exposure of food waste recycling practice. The aim of this study is to identify the physical and chemical parameters of composting food waste from Makanan Ringan Mas. The physical parameters were tested for temperature and pH value and the chemical parameter are Nitrogen, Phosphorus and Potassium. In this study, backyard composting was conducted with 6 reactors. Tapioca peel was used as fermentation liquid and soil and coconut grated were used as the fermentation bed. Backyard composting was conducted with six reactors. The overall results from the study showed that the temperature of the reactors were within the range which are from 30° to 50°C. The result of this study revealed that all the reactors which contain processed food waste tend to produce pH value within the range of 5 to 6 which can be categorized as slightly acidic. Meanwhile, the reactors which contained raw food waste tend to produce pH value within the range of 7 to 8 which can be categorized as neutral. The highest NPK obtained is from Reactor B that process only raw food waste. The average value of Nitrogen is 48540 mg/L, Phosphorus is 410 mg/L and Potassium is 1550 mg/L. From the comparison with common chemical fertilizer, it shows that NPK value from the composting are much lower than NPK of the common chemical fertilizer. However, comparison with NPK of organic fertilizer shown only slightly difference value in NPK.
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Busato, Jader G; Zandonadi, Daniel B; Mól, Alan R; Souza, Rafaela S; Aguiar, Kamilla P; Júnior, Fábio B Reis; Olivares, Fábio L
2017-02-01
Phosphorus-containing fertilizers play an important role in tropical agriculture owing to the well documented shortage of plant-available P in soils. Traditional P fertilizer production is based on chemical processing of insoluble rock phosphate (RP), which includes an acid treatment at high temperature. Processing the RP increases fertilizer costs, making it unavailable for undercapitalized and typically family-based farmers. Biotechnological methods have been proposed as an alternative to increase phosphate availability in RP. In this study, Burkholderia silvatlantica and Herbaspirillum seropedicae were co-inoculated into an RP-enriched compost with the aim of determining the effects of this technology on the levels of phosphatase activities and release of plant-available P. Inoculation of both microorganisms resulted in higher organic matter decomposition and higher humic acid formation in composting. Herbaspirillum seropedicae was the most promising microorganism for the production of acid and alkaline phosphatase enzymes. Both microorganisms presented potential to increase the supply of P from poorly soluble sources owing to increased levels of water-soluble P and citric acid P. Burkholderia silvatlantica and H. seropedicae in RP-enriched compost may represent an important biotechnological tool to reduce the overall time required for composting and increase the supply of P from poorly soluble sources. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
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Chen, Yaoning; Liu, Yao; Li, Yuanping; Wu, Yanxin; Chen, Yanrong; Zeng, Guangming; Zhang, Jiachao; Li, Hui
2017-11-01
Studies were performed to evaluate influence of biochar addition on physico-chemical process, heavy metals transformation and bacterial community diversity during composting of sediment with agricultural wastes. Simultaneously, the relationships between those parameters including heavy metals and bacterial community compositions were evaluated by redundancy analysis (RDA). The results show that the extraction efficiency of DTPA extractable heavy metals decreased in both piles, and reduced more in pile with biochar addition about 0.1-2.96%. Biochar addition dramatically influenced the bacterial community structure during the composting process. Moreover, the bacterial community composition was significantly correlated with C/N ratio, water soluble carbon (WSC), and organic matter (OM) (P<0.05) in pile with biochar addition; while significantly correlated with temperature, WSC, and C/N ratio in pile which was free of biochar. This study would provide some valuable information for improving the composting for disposal of river sediment with heavy metals contamination. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Evaluation of maifanite and silage as amendments for green waste composting.
Zhang, Lu; Sun, Xiangyang
2018-04-23
Composting is a popular method for recycling organic solid wastes including agricultural and forestry residues. However, traditional composting method is time consuming, generates foul smells, and produces an immature product. The effects of maifanite (MF; at 0%, 8.5%, and 13.5%) and/or silage (SG; at 0%, 25%, and 45%) as amendments on an innovative, two-stage method for composting green waste (GW) were investigated. The combined addition of MF and SG greatly improved composting conditions, reduced composting time, and enhanced compost quality in terms of composting temperature, bulk density, water-holding capacity, void ratio, pH, cation exchange capacity, ammonia nitrogen content, dissolved organic carbon content, crude fibre degradation, microbial numbers, enzyme activities, nutrient contents, and phytotoxicity. The two-stage composting of GW with 8.5% MF and 45% SG generated the highest quality and the most mature compost product and did so in only 21 days. With the optimized composting, the degradation rate of cellulose and hemicellulose reached 46.3 and 82.3%, respectively, and the germination index of Chinese cabbage and lucerne was 153 and 172%, respectively, which were all far higher than values obtained with the control. The combined effects of MF and SG on GW composting have not been previously explored, and this study therefore provided new and practical information. The comprehensive analyses of compost properties during and at the end of the process provided insight into underlying mechanisms. The optimized two-stage composting method may be a viable and sustainable alternative for GW management in that it converts the waste into a useful product. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Bacterial population dynamics in recycled mushroom compost leachate.
Safianowicz, Katarzyna; Bell, Tina L; Kertesz, Michael A
2018-06-01
Mushrooms are an important food crop throughout the world. The most important edible mushroom is the button mushroom (Agaricus bisporus), which comprises about 30% of the global mushroom market. This species is cultivated commercially on a selective compost that is produced predominantly from wheat straw/stable bedding and chicken manure, at a moisture content of around 70% (w/w) and temperatures of up to 80 °C. Large volumes of water are required to achieve this moisture content, and many producers therefore collect leachate from the composting windrows and bunkers (known in the industry as "goody water") and reuse it to wet the raw ingredients. This has the benefit of recycling and saving water and has the potential to enrich beneficial microorganisms that stimulate composting, but also the risk of enhancing pathogen populations that could reduce productivity. Here, we show by 16S rRNA gene sequencing that mushroom compost leachate contains a high diversity of unknown microbes, with most of the species found affiliated with the phyla Firmicutes and Proteobacteria. However, by far the most abundant species was the thermophile Thermus thermophilus, which made up approximately 50% of the bacterial population present. Although the leachate was routinely collected and stored in an aerated central storage tank, many of the bacterial species found in leachate were facultative anaerobes. However, there was no evidence for sulfide production, and no sulfate-reducing bacterial species were detected. Because T. thermophilus is important in the high temperature phase of composting, the use of recycled leachate as an inoculum for the raw materials is likely to be beneficial for the composting process.
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Feasibility study of a V-shaped pipe for passive aeration composting.
Ogunwande, Gbolabo A
2011-03-01
A V-shaped (Vs) pipe was improvised for composting of chicken litter in passive aeration piles. Three piles, equipped with horizontal (Ho), vertical (Ve) and Vs pipes were set up. The three treatments were replicated thrice. The effects of the aeration pipe on the physico-chemical properties of chicken litter and air distribution within the composting piles were investigated during composting. The properties monitored were temperature, pH, electrical conductivity, moisture content, total carbon, total nitrogen, total phosphorus and carbon-to-nitrogen ratio. Moisture level in the piles was replenished fortnightly to 60% during composting. The results of the study showed that all the piles attained the optimum temperature range (40-65°C) for effective composting and satisfied the requirements for sanitation. The non-significant (p > 0.05) temperature difference within the piles with Ve and Vs pipes indicated that these pipes were effective for uniform air distribution within the pile. The aeration pipe had significant (p ≤ 0.05) effect on pile temperature, pre-replenishment moisture content, pH and total phosphorus. In conclusion, the study showed that the Vs pipe is feasible and effective for passive aeration composting.
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Simple technologies for on-farm composting of cattle slurry solid fraction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brito, L.M., E-mail: miguelbrito@esa.ipvc.pt; Mourao, I.; Coutinho, J., E-mail: j_coutin@utad.pt
2012-07-15
Highlights: Black-Right-Pointing-Pointer Simple management techniques were examined for composting slurry solid fraction. Black-Right-Pointing-Pointer Composting slurry solids was effective without bulking agents, turning or rewetting. Black-Right-Pointing-Pointer Maximum rates of organic matter destruction were observed in short piles. Black-Right-Pointing-Pointer Thermophilic temperatures in tall piles maximised sanitation and moisture reduction. Black-Right-Pointing-Pointer The simple compost management approach maximised N retention and agronomic value. - Abstract: Composting technologies and control systems have reached an advanced stage of development, but these are too complex and expensive for most agricultural practitioners for treating livestock slurries. The development of simple, but robust and cost-effective techniques for composting animalmore » slurries is therefore required to realise the potential benefits of waste sanitation and soil improvement associated with composted livestock manures. Cattle slurry solid fraction (SF) was collected at the rates of 4 m{sup 3} h{sup -1} and 1 m{sup 3} h{sup -1} and composted in tall (1.7 m) and short (1.2 m) static piles, to evaluate the physicochemical characteristics and nutrient dynamics of SF during composting without addition of bulking agent materials, and without turning or water addition. Highest maximum temperatures (62-64 Degree-Sign C) were measured in tall piles compared to short piles (52 Degree-Sign C). However, maximum rates of organic matter (OM) destruction were observed at mesophilic temperature ranges in short piles, compared to tall piles, whereas thermophilic temperatures in tall piles maximised sanitation and enhanced moisture reduction. Final OM losses were within the range of 520-660 g kg{sup -1} dry solids and the net loss of OM significantly (P < 0.001) increased nutrient concentrations during the composting period. An advanced degree of stabilization of the SF was indicated by low final pile temperatures and C/N ratio, low concentrations of NH{sub 4}{sup +} and increased concentrations of NO{sub 3}{sup -} in SF composts. The results indicated that minimum intervention composting of SF in static piles over 168 days can produce agronomically effective organic soil amendments containing significant amounts of OM (772-856 g kg{sup -1}) and plant nutrients. The implications of a minimal intervention management approach to composting SF on compost pathogen reduction are discussed and possible measures to improve sanitation are suggested.« less
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Fernández, Francisco J; Sánchez-Arias, Virginia; Rodríguez, Lourdes; Villaseñor, José
2010-10-01
Representative samples of the following biowastes typically generated in Castilla La Mancha (Spain) were composted using a pilot-scale closed rotary drum composting reactor provided with adequate control systems: waste from the olive oil industry (olive mill waste; OMW), winery-distillery waste containing basically grape stalk and exhausted grape marc (WDW), and domestic sewage sludge. Composting these biowastes was only successful when using a bulking agent or if sufficient porosity was supported. OMW waste composting was not possible, probably because of its negligible porosity, which likely caused anaerobic conditions. WDW was successfully composted using a mixture of solid wastes generated from the same winery. SS was also successfully composted, although its higher heavy metal content was a limitation. Co-composting was an adequate strategy because the improved mixture characteristics helped to maintain optimal operating conditions. By co-composting, the duration of the thermophilic period increased, the final maturity level improved and OMW was successfully composted. Using the proposed reactor, composting could be accelerated compared to classical outdoor techniques, enabling easy control of the process. Moisture could be easily controlled by wet air feeding and leachate recirculation. Inline outlet gas analysis helped to control aerobic conditions without excessive aeration. The temperature reached high values in a few days, and sufficient thermal requirements for pathogen removal were met. The correct combination of biowastes along with appropriate reactor design would allow composting as a management option for such abundant biowastes in this part of Spain. (c) 2010 Elsevier Ltd. All rights reserved.
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Chen, Chih-Yu; Kuo, Jong-Tar; Chung, Ying-Chien
2013-01-01
The use of matured compost as an inoculation agent to improve the composting of vegetable and fruit wastes in a laboratory-scale composter was evaluated, and the commercial feasibility of this approach in a pilot-scale (1.8 x 10(4) L) composter was subsequently confirmed. The effect of aeration rate on the physico-chemical and biological properties of compost was also studied. Aeration rate affected the fermentation temperature, moisture content, pH, O2 consumption rate, CO2 production rate and the formation of odour. The optimal aeration rate was 2.5 L air/kg dry solid/min. The CO2 production rate approached the theoretical value during composting and was linearly dependent on temperature, indicating that the compost system had good operating characteristics. The inoculation of cellulolytic bacteria and deodorizing bacteria to compost in the pilot-scale composter led to an 18.2% volatile solids loss and a 64.3% volume reduction ratio in 52 h; only 1.5 ppm(v) odour was detected. This is the first study to focus on both operating performance and odour removal in a pilot-scale composter.
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Composting of pig manure and forest green waste amended with industrial sludge.
Arias, O; Viña, S; Uzal, M; Soto, M
2017-05-15
The aim of this research was to study the composting of chestnut forest green waste (FGW) from short rotation chestnut stands amended with sludge resulting from the manufacture of Medium Density Fibreboard (MDFS) and pig manure (PM). Both FGW and MDFS presented low biodegradation potential but different characteristics in granulometry and bulk density that make its mixture of interest to achieve high composting temperatures. PM decreased the C/N ratio of the mixture and increased its moisture content (MC). Three mixtures of MDFS:FGW at volume ratios of 1:1.3 (M2), 1:2.4 (M3) and 0:1 (M4) were composted after increasing its MC to about 70% with PM. A control with food waste (OFW) and FGW (1:2.4 in volume) (M1) was run in parallel. Watering ratios reached 0.25 (M1), 1.08 (M2) 1.56 (M3) and 4.35 (M4) L PM/kg TS of added solids wastes. Treatments M2 and M3 reached a thermophilic phase shorter than M1, whilst M4 remained in the mesophilic range. After 48days of composting, temperature gradients in respect to ambient temperature were reduced, but the mineralization process continued for around 8months. Final reduction in total organic carbon reached 35-56%, depending mainly on the content in MDFS. MDFS addition to composting matrices largely reduced nitrogen losses, which range from 22% (M2) to 37% (M3) and 53% (M4). Final products had high nutrient content, low electrical conductivity and low heavy metal content which make it a valuable product for soil fertilization, right to amend in the chestnut forests and as a pillar of their sustainable management. Copyright © 2017 Elsevier B.V. All rights reserved.
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Oishi, Ryu; Tada, Chika; Asano, Ryoki; Yamamoto, Nozomi; Suyama, Yoshihisa; Nakai, Yutaka
2012-05-01
A recent study showed that ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) coexist in the process of cattle manure composting. To investigate their physiological characteristics, liquid cultures seeded with fermenting cattle manure compost were incubated at various temperatures (37°C, 46°C, or 60°C) and ammonium concentrations (0.5, 1, 4, or 10 mM NH (4) (+) -N). The growth rates of the AOB and AOA were monitored using real-time polymerase chain reaction analysis targeting the bacterial and archaeal ammonia monooxygenase subunit A genes. AOB grew at 37°C and 4 or 10 mM NH (4) (+) -N, whereas AOA grew at 46°C and 10 mM NH (4) (+) -N. Incubation with allylthiourea indicated that the AOB and AOA grew by oxidizing ammonia. Denaturing gradient gel electrophoresis and subsequent sequencing analyses revealed that a bacterium related to Nitrosomonas halophila and an archaeon related to Candidatus Nitrososphaera gargensis were the predominant AOB and AOA, respectively, in the seed compost and in cultures after incubation. This is the first report to demonstrate that the predominant AOA in cattle manure compost can grow and can probably oxidize ammonia under moderately thermophilic conditions.
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Stoknes, Ketil; Beyer, David M; Norgaard, Erik
2013-07-01
Source-separated food waste is increasingly being treated by means of hygienisation followed by anaerobic digestion. The fibrous digester residue (digestate) is a potential mushroom substrate, while heat from the biogas can provide steam for the cultivation process. Using bag experiments the present study explored digestate as a full substitute for chicken manure conventionally used in mushroom composts. After mixing, a rapid temperature development in the compost was stimulated by a small amount of chicken manure, as aerobic microbial seeding. Mechanical elimination of lumps was essential for full mycelial colonisation. Three straw digestate composts had Agaricus bisporus mushroom yields above 370 g kg⁻¹ substrate. The optimal compost water content was 600 g kg⁻¹ at inoculation, and high digestate content (up to 500 g kg⁻¹ by dry weight) did not affect yield for this species. High yields of A. subrufescens (200 g kg⁻¹) were related to drier composts of lower digestate content (more straw) and lower pH values at inoculation. Digestate successfully substituted chicken manure in straw composts without affecting mushroom yields for both species. There were no clear differences between straw digestate and control composts in terms of mushroom dry matter, size, nitrogen or ash content. © 2012 Society of Chemical Industry.
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Time domain reflectometry measured moisture content of sewage sludge compost across temperatures.
Cai, Lu; Chen, Tong-Bin; Gao, Ding; Liu, Hong-Tao; Chen, Jun; Zheng, Guo-Di
2013-01-01
Time domain reflectometry (TDR) is a prospective measurement technology for moisture content of sewage sludge composting material; however, a significant dependence upon temperature has been observed. The objective of this study was to assess the impacts of temperature upon moisture content measurement and determine if TDR could be used to monitor moisture content in sewage sludge compost across a range of temperatures. We also investigated the combined effects of temperature and conductivity on moisture content measurement. The results revealed that the moisture content of composting material could be determined by TDR using coated probes, even when the measured material had a moisture content of 0.581 cm(3)cm(-3), temperature of 70°C and conductivity of 4.32 mS cm(-1). TDR probes were calibrated as a function of dielectric properties that included temperature effects. When the bulk temperature varied from 20°C to 70°C, composting material with 0.10-0.70 cm(3)cm(-3) moisture content could be measured by TDR using coated probes, and calibrations based on different temperatures minimized the errors. Copyright © 2012. Published by Elsevier Ltd.
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Application of aerobic composting system for space agriculture
NASA Astrophysics Data System (ADS)
Oshima, Tairo; Yoshii, Takahiro; Moriya, Toshiyuki; Yamashita, Masamichi
Composting is a classical technique to decompose organic wastes such as animal bodies, straw, paper, raw sludge, and so on. Compared with burning of wastes, the composting method has many advantages. It is an inexpensive and safer method because of its self-heating without spending extra energy resources. It does not emit toxic pollutants such as dioxin, NOx , and SOx . The composting products can be used as organic fertilizers for agricultural production. Composting is a promising way for digesting organic wastes safely on spaceships or manned exploration on extraterrestrial planets. We have developed a small scale high-temperature composter in order to examine its feasobility to operate food waste disposing facility and fertilizer production in space. This composter has a heated reaction vessel containing compost soil (seed bacteria) provided by a compost factory. To determine the optimal condition for its operation, we analyzed the effect of temperature on metabolic activity (CO2 production rate), and water content. The dynamics of microbial community was studied by polymerase chain reaction - denaturing gradient gel electrophoresis (PCR-DGGE). Water content was maintained to a range between 27% and 40% by continuously adding water. The highest CO2 emission was observed at around 70° C. PCR-DGGE analysis shows that the bacterial community of the compost soil is dramatically changed by changing reaction temperature. We will discuss the application of the composter in space in order to establish the closed recycling loop of bio-elements in space agriculture.
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Role of psychrotrophic bacteria in organic domestic waste composting in cold regions of China.
Hou, Ning; Wen, Luming; Cao, Huiming; Liu, Keran; An, Xuejiao; Li, Dapeng; Wang, Hailan; Du, Xiaopeng; Li, Chunyan
2017-07-01
To study the influence of psychrotrophic bacteria on organic domestic waste (ODW) composting in cold regions, twelve new efficient psychrotrophic composting strains were isolated. Together with the published representative composting strains, a phylogenetic tree was constructed showing that although the strains belong to the same phylum, the genera were markedly different. The twelve strains were inoculated into the ODW in the composting reactor at 13°C. After treatment, the indices of temperature, moisture content, pH, electrical conductivity, C/N, ammonium nitrogen, and nitrate nitrogen indicated that the compost had reached maturity. The thermophilic phase was reached at 17d, and composting was completed at 42d, a markedly shorter composting time than that in previous studies. High-throughput sequencing indicated that the inoculative strains became the dominant community during the mesophilic phase and that they enhanced the stability of the microbial community structure. Thus, psychrotrophic bacteria played a key role in low-temperature composting. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Jiang, Jishao; Kang, Kang; Chen, Dan; Liu, Ningning
2018-02-01
Delayed addition of Nitrogen (N)-rich and acidic substrates was investigated to evaluate its effects on N loss and compost quality during the composting process. Three different delayed adding methods of N-rich (pig manure) and acidic substrates (phosphate fertilizer and rotten apples) were tested during the pig manure and wheat straw is composting. The results showed that delayed addition of pig manure and acidic materials led two temperature peaks, and the durations of two separate thermophilic phase were closely related to the amount of pig manure. Delayed addition reduced total N loss by up to 14% when using superphosphate as acidic substrates, and by up to 12% when using rotten apples as acidic substrates, which is mainly due to the decreased NH 3 emissions. At the end of composting, delayed the addition of pig manure caused a significant increase in the HS (humus substance) content, and the highest HS content was observed when 70% of the pig manure was applied at day 0 and the remaining 30% was applied on day 27. In the final compost, the GI in all treatments almost reached the maturity requirement by exceeding 80%. The results suggest that delayed addition of animal manure and acidic substrates could prevent the N loss during composting and improve the compost quality. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Enhanced compositing of radiation disinfected sewage sludge
NASA Astrophysics Data System (ADS)
Kawakami, W.; Hashimoto, S.
Studies on isothermal composting of radiation disinfected sewage sludge and liquid chromatography of water extracts of the products were carried out. The optimum temperature and pH were around 50 °C and 7-8, respectively. The repeated use of products as seeds increased the rate of CO 2 evolution. The rate reached a maximum within 10 hours and decreased rapidly, and the CO 2 evolution ceased after about 3 days. The conversion of organic carbon to carbon dioxide attained to about 40% for the repeated use of products as seeds at the optimum conditions. As long as seeds in available were used, no remarkable difference was found in the composting of unirradiated and irradiated sludges. The composting process using radiation, however, can be carried out at the optimum conditions and is expected to shorten the composting period, because it is not necessary to keep fermentation temperature higher to reduce pathogen in sludge. Liquid chromatographic studies of the products showed that low molecular components decreased and higher molecular ones increased with fermentation. An index expressing the degree of reduction of easily decomposable organics was presented. The index also showed that the optimum temperature for fermentation was 50 °C, and that the easily decomposable organics disappeared above 30% of the conversion of organic carbon.
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Chakroune, K; Bouakka, M; Hakkou, A
2005-01-01
Composting of date palm (Phoenix dactylifera L.) residues contaminated with Fusarium f.sp oxysporum albedinis, causal agent of the vascular wilt (Bayoud) of the date palm, has been achieved. The effect of the aeration of the piles by manual turning has been studied. The maintenance of an adequate humidity of 60%-70%, necessary to the good progress of the composting process, required the contribution of 11.4 L of water/kg of the dried residues. The evolution of the temperatures in the three piles presents the same phases. A latency phase, followed after 2-3 d of composting by a thermophilic phase, which lasts about 24 d, where the temperature remains elevated between 50 and 70 degrees C. Then a cooling phase that takes about 15 d, during which the temperatures fall to values between 25 and 35 degrees C, near room temperature. Fusarium f.sp oxysporum albedinis is eliminated completely during the thermophilic phase of composting, and increasing frequencies of turning accelerate its disappearance to a certain extent. On the other hand, pH remained steady and relatively basic oscillating between 8.2 and 8.7. Ninety percent (90%) of the the date palm residues are composed exclusively of organic matters. The total nitrogen represents only 0.4%. The contribution of manure decreases the ratio of carbon to nitrogen (C/N) from 115 to 48 in the initial mixture. After 80 d of composting and according to the frequency of return up, there is a reduction of the granulometry of the substratum, the C/N ratio (from 29% to 44%), the organic matter (from 15% to 23%), the total volume (from 25% to 35%), and of the dry weight of the swaths (from 16% to 24%). On the other hand there is an increase in total nitrogen rate (from 20% to 40%) and in the mineral matter (from 23% to 35%).
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Liang, C; Das, K C; McClendon, R W
2003-01-01
To understand the relationships between temperature, moisture content, and microbial activity during the composting of biosolids (municipal wastewater treatment sludge), well-controlled incubation experiments were conducted using a 2-factor factorial design with six temperatures (22, 29, 36, 43, 50, and 57 degrees C) and five moisture contents (30, 40, 50, 60, and 70%). The microbial activity was measured as O2 uptake rate (mg g(-1) h(-1)) using a computer controlled respirometer. In this study, moisture content proved to be a dominant factor impacting aerobic microbial activity of the composting blend. Fifty percent moisture content appeared to be the minimal requirement for obtaining activities greater than 1.0 mg g(-1) h(-1). Temperature was also documented to be an important factor for biosolids composting. However, its effect was less influential than moisture content. Particularly, the enhancement of composting activities induced by temperature increment could be realized by increasing moisture content alone.
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NASA Astrophysics Data System (ADS)
Smet, Erik; Van Langenhove, Herman; De Bo, Inge
Two different biowaste composting techniques were compared with regard to their overall emission of volatile compounds during the active composting period. In the aerobic composting process, the biowaste was aerated during a 12-week period, while the combined anaerobic/aerobic composting process consisted of a sequence of a 3-week anaerobic digestion (phase I) and a 2-week aeration period (phase II). While the emission of volatiles during phase I of the combined anaerobic/aerobic composting process was measured in a full-scale composting plant, the aerobic stages of both composting techniques were performed in pilot-scale composting bins. Similar groups of volatile compounds were analysed in the biogas and the aerobic composting waste gases, being alcohols, carbonyl compounds, terpenes, esters, sulphur compounds and ethers. Predominance of alcohols (38% wt/wt of the cumulative emission) was observed in the exhaust air of the aerobic composting process, while predominance of terpenes (87%) and ammonia (93%) was observed in phases I and II of the combined anaerobic/aerobic composting process, respectively. In the aerobic composting process, 2-propanol, ethanol, acetone, limonene and ethyl acetate made up about 82% of the total volatile organic compounds (VOC)-emission. Next to this, the gas analysis during the aerobic composting process revealed a strong difference in emission profile as a function of time between different groups of volatiles. The total emission of VOC, NH 3 and H 2S during the aerobic composting process was 742 g ton -1 biowaste, while the total emission during phases I and II of the combined anaerobic/aerobic composting process was 236 and 44 g ton -1 biowaste, respectively. Taking into consideration the 99% removal efficiency of volatiles upon combustion of the biogas of phase I in the electricity generator, the combined anaerobic/aerobic composting process can be considered as an attractive alternative for aerobic biowaste composting because of its 17 times lower overall emission of the volatiles mentioned.
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Xi, Beidou; He, Xiaosong; Dang, Qiuling; Yang, Tianxue; Li, Mingxiao; Wang, Xiaowei; Li, Dan; Tang, Jun
2015-11-01
In this study, PCR-DGGE method was applied to investigate the impact of multi-stage inoculation treatment on the community composition of bacterial and fungal during municipal solid wastes (MSW) composting process. The results showed that the high temperature period was extended by the multi-stage inoculation treatment, 1day longer than initial-stage inoculation treatment, and 5days longer than non-inoculation treatment. The temperature of the secondary fermentation increased to 51°C with multi-stage inoculation treatment. The multi-stage inoculation method improved the community diversity of bacteria and fungi that the diversity indexes reached the maximum on the 17days and 20days respectively, avoided the competition between inoculations and indigenous microbes, and enhanced the growth of dominant microorganisms. The DNA sequence indicated that various kinds of uncultured microorganisms with determined ratios were detected, which were dominant microbes during the whole fermentation process. These findings call for further researches of compost microbial cultivation technology. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Assessment of a composting process for the treatment of beef cattle manure.
Magrí, Albert; Teira-Esmatges, M Rosa
2015-01-01
The intensive breeding of beef cattle in Juncosa de les Garrigues (Catalonia, Spain) leads to the production of a large volume of manure that needs appropriate management. Land application in the area at agronomic rates is not enough to ensure good management practices, making necessary extended on-farm storage and the export of part of the production to long distances. In this context, the implementation of a collective treatment based on composting could help in enhancing the handling of manure. We assessed a full-scale composting process based on turned windrows (W), and involving treatment of beef cattle manure (CM) alone (two typologies were considered according to carbon-to-nitrogen ratios of ~25 (CM1, W1) and ~14 (CM2, W2)), or mixed with bulking agent (CM2/BA, W3) and dewatered digested sewage sludge (CM2/BA/DDSS, W4). Composting significantly improved the transportability of nutrients (final volumes were 40-54% of the initial volume). Temperature >55°C was reached in all the treatments but following different time patterns. Under the applied conditions of turning and rewetting, 14 weeks of processing did not ensure the production of stable, and mature, compost. Thus, only compost from W1 attained the maximum degree of stability as well as concentration of ammonium-N < 0.01% (with ammonium-N/nitrate-N ratio of 0.2) and low phytotoxicity. However, high pH, salinity, and heavy metal contents (Cu and Zn) may limit its final use. Addition of BA was advised to be kept to minimum, whereas use of DDSS as a co-substrate was not recommended in agreement to the higher loss of N and levels of heavy metals in the final compost.
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Xu, Shanwei; Harvey, Amanda; Barbieri, Ruth; Reuter, Tim; Stanford, Kim; Amoako, Kingsley K.; Selinger, Leonard B.; McAllister, Tim A.
2016-01-01
Anthrax outbreaks in livestock have social, economic and health implications, altering farmer’s livelihoods, impacting trade and posing a zoonotic risk. Our study investigated the survival of Bacillus thuringiensis and B. anthracis spores sporulated at 15, 20, or 37°C, over 33 days of composting. Spores (∼7.5 log10 CFU g-1) were mixed with manure and composted in laboratory scale composters. After 15 days, the compost was mixed and returned to the composter for a second cycle. Temperatures peaked at 71°C on day 2 and remained ≥55°C for an average of 7 days in the first cycle, but did not exceed 55°C in the second. For B. thuringiensis, spores generated at 15 and 21°C exhibited reduced (P < 0.05) viability of 2.7 and 2.6 log10 CFU g-1 respectively, as compared to a 0.6 log10 CFU g-1 reduction for those generated at 37°C. For B. anthracis, sporulation temperature did not impact spore survival as there was a 2.5, 2.2, and 2.8 log10 CFU g-1 reduction after composting for spores generated at 15, 21, and 37°C, respectively. For both species, spore viability declined more rapidly (P < 0.05) in the first as compared to the second composting cycle. Our findings suggest that the duration of thermophilic exposure (≥55°C) is the main factor influencing survival of B. anthracis spores in compost. As sporulation temperature did not influence survival of B. anthracis, composting may lower the viability of spores associated with carcasses infected with B. anthracis over a range of sporulation temperatures. PMID:27303388
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Wang, Xiaojun; Pan, Songqing; Zhang, Zhaoji; Lin, Xiangyu; Zhang, Yuzhen; Chen, Shaohua
2017-01-01
To determine the suitable feeding ratio for fed-batch aerobic composting, four fermenters were operated by adding 0%, 5%, 10% or 15% of food waste every day. The results showed that the 5% and 10% treatments were able to maintain continuous thermophilic conditions, while the 15% treatment performed badly in regard to composting temperature, which was probably due to the negative effects of excessive moisture on microbial activity. As composting proceeded, both the 5% and the 10% treatments reached maturity and achieved weight losses of approximately 65%. High-throughput sequencing results indicated that Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria were the dominant phyla of the community structure. The communities sampled at the thermophilic phases had high similarity and relatively low diversity, while species diversity increased in the maturity phase. This study was devoted to optimizing the fed-batch composting process and assessing bacterial communities, both of which were supplied as a reference for practical application. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Chowdhury, Md Albarune; de Neergaard, Andreas; Jensen, Lars Stoumann
2014-01-01
Solid-liquid separation of animal slurry, with solid fractions used for composting, has gained interest recently. However, efficient composting of separated animal slurry solid fractions (SSFs) requires a better understanding of the process dynamics in terms of important physical parameters and their interacting physical relationships in the composting matrix. Here we monitored moisture content, bulk density, particle density and air-filled porosity (AFP) during composting of SSF collected from four commercially available solid-liquid separators. Composting was performed in laboratory-scale reactors for 30 days (d) under forced aeration and measurements were conducted on the solid samples at the beginning of composting and at 10-d intervals during composting. The results suggest that differences in initial physical properties of SSF influence the development of compost maximum temperatures (40-70 degreeC). Depending on SSF, total wet mass and volume losses (expressed as % of initial value) were up to 37% and 34%, respectively. After 30 d of composting, relative losses of total solids varied from 17.9% to 21.7% and of volatile solids (VS) from 21.3% to 27.5%, depending on SSF. VS losses in all composts showed different dynamics as described by the first-order kinetic equation. The estimated component particle density of 1441 kg m-3 for VS and 2625 kg m-3 for fixed solids can be used to improve estimates of AFP for SSF within the range tested. The linear relationship between wet bulk density and AFP reported by previous researchers held true for SSF.
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Putranto, Aditya; Chen, Xiao Dong
2017-05-01
During composting, self-heating may occur due to the exothermicities of the chemical and biological reactions. An accurate model for predicting maximum temperature is useful in predicting whether the phenomena would occur and to what extent it would have undergone. Elevated temperatures would lead to undesirable situations such as the release of large amount of toxic gases or sometimes would even lead to spontaneous combustion. In this paper, we report a new model for predicting the profiles of temperature, concentration of oxygen, moisture content and concentration of water vapor during composting. The model, which consists of a set of equations of conservation of heat and mass transfer as well as biological heating term, employs the reaction engineering approach (REA) framework to describe the local evaporation/condensation rate quantitatively. A good agreement between the predicted and experimental data of temperature during composting of sewage sludge is observed. The modeling indicates that the maximum temperature is achieved after some 46weeks of composting. Following this period, the temperature decreases in line with a significant decrease in moisture content and a tremendous increase in concentration of water vapor, indicating the massive cooling effect due to water evaporation. The spatial profiles indicate that the maximum temperature is approximately located at the middle-bottom of the compost piles. Towards the upper surface of the piles, the moisture content and concentration of water vapor decreases due to the moisture transfer to the surrounding. The newly proposed model can be used as reliable simulation tool to explore several geometry configurations and operating conditions for avoiding elevated temperature build-up and self-heating during industrial composting. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Kazamias, Georgios; Roulia, Maria; Kapsimali, Ioanna; Chassapis, Konstantinos
2017-12-01
In the present work, a new simple and quick eco-friendly method is discussed to handle effectively the green wastes and produce a sustainable peat substitute of high quality on the large scale. Principal physicochemical parameters, i.e., temperature, moisture, specific weight, pH, electrical conductivity and, also, microorganisms, organic matter, humic substances, total Kjeldahl nitrogen and total organic carbon, C/N ratio, ash, metal content and phytotoxicity, were monitored systematically. Humic substances content values were interrelated to both C/N ratio and pH values and, similarly, bulk density, TOC, TKN, C/N, GI, ash and organic matter were found interconnected to each other. A novel biocatalyst, extremely rich in soil microorganisms, prepared from compost extracts and peaty lignite, accelerated the biotransformation. Zeolite was also employed. The compost does not demonstrate any phytotoxicity throughout the entire biotransformation process and has increased humic substances content. Both humic substances content and germination index can be employed as maturation indices of the compost. Addition of compost, processed for 60 days only, in cultivations of grass plants led to a significant increase in the stem mass and root size, annotating the significant contribution of the compost to both growth and germination. The product obtained is comparable to peat humus, useful as peat substitute and can be classified as a first class soil conditioner suitable for organic farming. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Temperature measurement and performance assessment of the experimental composting bioreactor
NASA Astrophysics Data System (ADS)
Bajko, Jaroslav; Fišer, Jan; Jícha, Miroslav
2018-06-01
Considerable amount of heat produced during composting of organic matter is usually lost to the surrounding environment. In order to utilize this potential heat source, biomass is composted in mounds or vessels and excess thermal energy is captured via heat exchangers and transported to the site for space heating, preparation of utility water and other applications. The aim of this experimental research is to measure the temperature profiles in a pilot-scale composting bioreactor and assess its performance.
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Uma, R N; Manjula, G; Meenambal, T
2007-04-01
The reaction rates and activation energy in aerobic composting processes for yard waste were determined using specifically designed reactors. Different mixture ratios were fixed before the commencement of the process. The C/N ratio was found to be optimum for a mixture ratio of 1:6 containing one part of coir pith to six parts of other waste which included yard waste, yeast sludge, poultry yard waste and decomposing culture (Pleurotosis). The path of stabilization of the wastes was continuously monitored by observing various parameters such as temperature, pH, Electrical Conductivity, C.O.D, VS at regular time intervals. Kinetic analysis was done to determine the reaction rates and activation energy for the optimum mixture ratio under forced aeration condition. The results of the analysis clearly indicated that the temperature dependence of the reaction rates followed the Arrhenius equation. The temperature coefficients were also determined. The degradation of the organic fraction of the yard waste could be predicted using first order reaction model.
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Liao, Hanpeng; Lu, Xiaomei; Rensing, Christopher; Friman, Ville Petri; Geisen, Stefan; Chen, Zhi; Yu, Zhen; Wei, Zhong; Zhou, Shungui; Zhu, Yongguan
2018-01-02
Composting is an efficient way to convert organic waste into fertilizers. However, waste materials often contain large amounts of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) that can reduce the efficacy of antibiotic treatments when transmitted to humans. Because conventional composting often fails to remove these compounds, we evaluated if hyperthermophilic composting with elevated temperature is more efficient at removing ARGs and MGEs and explored the underlying mechanisms of ARG removal of the two composting methods. We found that hyperthermophilic composting removed ARGs and MGEs more efficiently than conventional composting (89% and 49%, respectively). Furthermore, the half-lives of ARGs and MGEs were lower in hyperthermophilic compositing compared to conventional composting (67% and 58%, respectively). More-efficient removal of ARGs and MGEs was associated with a higher reduction in bacterial abundance and diversity of potential ARG hosts. Partial least-squares path modeling suggested that reduction of MGEs played a key role in ARG removal in hyperthermophilic composting, while ARG reduction was mainly driven by changes in bacterial community composition under conventional composting. Together these results suggest that hyperthermophilic composting can significantly enhance the removal of ARGs and MGEs and that the mechanisms of ARG and MGE removal can depend on composting temperature.
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USDA-ARS?s Scientific Manuscript database
Composting management or conditions that result in inadequate exposure of the compostable materials to destructive time-temperature regimens can result in survival of enteric human pathogens. Bacterial pathogens, such as Escherichia coli O157:H7 and Salmonella spp., can regrow in finished compost. ...
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Michel, F C; Reddy, C A; Forney, L J
1995-01-01
The fate of the widely used lawn care herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) during the composting of yard trimmings consisting of primarily leaves and grass is an important unexplored question. In this study, we determined the extent of 2,4-D mineralization, incorporation into humic matter, volatilization, and sorption during the composting of yard trimmings. Yard trimmings (2:1 [wt/wt] leaves-grass) were amended with 14C-ring-labeled 2,4-D (17 mg/kg of dry weight) and composted in a temperature-controlled laboratory scale compost system. During composting, thermophilic microbes were numerically dominant, reaching a maximum of 2 x 10(11)/g. At the end of composting, 46% of the organic matter (OM) present in the yard trimmings was lost and the compost was stable, with an oxygen uptake rate of 0.09 mg of O2 per g of OM per h, and was well humified (humification index, 0.39). Mineralization of the OM temporally paralleled mineralization of 2,4-D. In the final compost, 47% of the added 2,4-D carbon was mineralized, about 23% was complexed with high-molecular-weight humic acids, and about 20% was not extractable (humin fraction). Less than 1% of the added 14C was present in water expressed from the finished compost, suggesting a low potential for leaching of 2,4-D. Very little volatilization of 2,4-D occurred during composting. It is of interest that our results indicate active mineralization of 2,4-D at composting temperatures of 60 degrees C because microbial 2,4-D degradation at thermophilic temperatures has not been previously documented. PMID:7618868
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Application of a recyclable plastic bulking agent for sewage sludge composting.
Zhou, Hai-Bin; Ma, Chuang; Gao, Ding; Chen, Tong-Bin; Zheng, Guo-Di; Chen, Jun; Pan, Tian-Hao
2014-01-01
A recyclable plastic bulking agent (RPBA) that can be screened and reused was developed to improve sludge composting and to reduce costs. Two RPBAs were developed: RPBA35 (35 mm in diameter) and RPBA50 (50mm in diameter). The objective was to study the influence of size and quantity of RPBA on temperature, oxygen content, water removal during sludge composting, and phytotoxicity of the compost. RPBAs of both sizes improved the temperature, oxygen supply, and water removal compared with the treatment with no RPBA, and obtained phytotoxic-free compost. RPBA50 more effectively removed water than RPBA35. Oxygen diffusion rate in the composting pile containing RPBA50 was higher than in the treatment with no RPBA. When the RPBA50: sludge mixture ratio was above 1:1.5, the period over which the temperature exceeded 55 °C was insufficient to meet the harmless treatment requirement. The water evaporation rate was highest at a ratio of 1:2. Copyright © 2013. Published by Elsevier Ltd.
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PRACTICAL SIMULATION OF COMPOSTING IN THE LABORATORY
A closed incubation system was developed for laboratory simulation of composting conditions at the interior of a large compost pile. A conductive heat flux control system (CHFC) was used to adjust the temperature of the internal wall to that of the compost center and compensate f...
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Effect of turning frequency on co-composting pig manure and fungus residue.
Jiang-Ming, Zhou
2017-03-01
Composting of agricultural wastes not only can reduce environmental pollution caused by improper disposal, but also can recycle agricultural wastes and transform them into highly valuable products, such as fertilizers or soil conditioners, for agricultural applications. However, the composting process and final product are easily affected by the limited oxygen supply that results from insufficient aeration, especially in the center of a large-scale windrow. Hence, a pilot-scale experiment was conducted to investigate the effects of the turning frequency on the composting efficiency and compost quality of used pig manure and fungus residue. Physical and chemical characteristics were measured over the course of 63 days of composting. The data indicate that higher temperatures and more rapid moisture removal generally result from a turning treatment of once every 2-4 days than in fewer, or no, turning treatments. The total nitrogen, total phosphorus, and total potassium contents increased in all windrows as the organic matter content decreased, but both the increases and decrease were greater in windrows that were turned more frequently. The reduction of the organic matter mass by 53.7-66.0% for a turning of once every 2-8 days is significantly higher than that for the static windrow (39.1%). Although there is an increase in nitrogen mass loss with an increased turning frequency, lower nitrogen mass losses (12.7-25.7%) in all treatments were noted compared with previous studies. A final compost product with less moisture, less weight, higher nutrient content (N, P, and K), and greater stability was obtained in windrows with turning frequencies of once every 2-4 days, which is recommended when composting pig manure and fungus residue. Composting of agricultural wastes not only can reduce environmental pollution caused by improper disposal, but recycling of agricultural wastes transforms them into highly valuable products, such as fertilizers or soil conditioners, for agricultural applications. However, the composting process and final product are easily affected by the limited oxygen supply that results from insufficient aeration, especially in the center of a large-scale windrow. Hence, a pilot-scale experiment was conducted to investigate the effects of the turning frequency on the composting efficiency and compost quality of used pig manure and fungus residue, so as to capture an operational technique suitable for the effective co-composting pig manure and edible fungi residue for a large-scale composting plant.
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Simple technologies for on-farm composting of cattle slurry solid fraction.
Brito, L M; Mourão, I; Coutinho, J; Smith, S R
2012-07-01
Composting technologies and control systems have reached an advanced stage of development, but these are too complex and expensive for most agricultural practitioners for treating livestock slurries. The development of simple, but robust and cost-effective techniques for composting animal slurries is therefore required to realise the potential benefits of waste sanitation and soil improvement associated with composted livestock manures. Cattle slurry solid fraction (SF) was collected at the rates of 4m(3)h(-1) and 1m(3)h(-1) and composted in tall (1.7 m) and short (1.2m) static piles, to evaluate the physicochemical characteristics and nutrient dynamics of SF during composting without addition of bulking agent materials, and without turning or water addition. Highest maximum temperatures (62-64 °C) were measured in tall piles compared to short piles (52 °C). However, maximum rates of organic matter (OM) destruction were observed at mesophilic temperature ranges in short piles, compared to tall piles, whereas thermophilic temperatures in tall piles maximised sanitation and enhanced moisture reduction. Final OM losses were within the range of 520-660 g kg(-1) dry solids and the net loss of OM significantly (P<0.001) increased nutrient concentrations during the composting period. An advanced degree of stabilization of the SF was indicated by low final pile temperatures and C/N ratio, low concentrations of NH(4)(+) and increased concentrations of NO(3)(-) in SF composts. The results indicated that minimum intervention composting of SF in static piles over 168 days can produce agronomically effective organic soil amendments containing significant amounts of OM (772-856 g kg(-1)) and plant nutrients. The implications of a minimal intervention management approach to composting SF on compost pathogen reduction are discussed and possible measures to improve sanitation are suggested. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Farah Nadia, Omar; Xiang, Loo Yu; Lie, Lee Yei; Chairil Anuar, Dzulkornain; Mohd Afandi, Mohammed P; Azhari Baharuddin, Samsu
2015-02-01
Co-composting of poultry manure and rubber wood sawdust was performed with the ratio of 2:1 (V/V) for a period of 60 days. An investigation was carried out to study the extracellular enzymatic activities and structural degradation utilizing Fourier transform infrared spectroscopy (FT-IR), thermogravimetry and differential thermal analysis (TG/DTA) and scanning electron microscopy (SEM). The microbial succession was also determined by using denaturing gel gradient electrophoresis (DGGE). The compost was able to reach its highest temperature of 71°C at day 3 and stabilized between 30 and 40°C for 8 weeks. CMCase, FPase and β-glucosidase acted synergistically in order to degrade the cellulosic substrate. The xylanase activities increased gradually during the composting and reached the peak value of 11.637 U/g on day 35, followed by a sharp decline. Both LiP and MnP activities reached their peak values on day 35 with 0.431 and 0.132 U/g respectively. The FT-IR spectra revealed an increase in aromaticity and a decrease in aliphatic compounds such as carbohydrates as decomposition proceeded. TGA/DTG data exhibited significant changes in weight loss in compost samples, indicating degradation of organic matter. SEM micrographs showed higher amounts of parenchyma exposed on the surface of rubber wood sawdust at day 60, showing significant degradation. DGGE and 16S rDNA analyses showed that Burkholderia sp., Pandoraea sp., and Pseudomonas sp. were present throughout the composting process. Ornithinibacillus sp. and Castellaniella ginsengisoli were only found in the initial stage of the composting, while different strains of Burkholderia sp. also occurred in the later stage of composting. Copyright © 2014. Published by Elsevier B.V.
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Ebrahimzadeh, Reza; Ghazanfari Moghaddam, Ahmad; Sarcheshmehpour, Mehdi; Mortezapour, Hamid
2017-12-01
Biomass degradation kinetics of the composting process for kitchen waste, pruned elm tree branches and sheep manure were studied to model changes in volatile solids (VS) over time. Three experimental reactors containing raw mixtures with a carbon to nitrogen (C/N) ratio of 27:1 and a moisture content of 65% were prepared. During the composting process two of the reactors used forced air and the third used natural aeration. The composting stabilization phases in all reactors were completed in 30 days. During this period, composting indexes such as temperature, moisture content and VS changes were recorded. Elementary reactions were used for kinetics modeling of the degradation process. Results showed that the numerical values of rate constant ( k) for zero-order ranged from 0.86 to 1.03 VS×day -1 , for first-order models it ranged from 0.01 to 0.02 day -1 , for second-order the range was from 1.36×10 -5 to 1.78×10 -5 VS -1 ×day -1 and for n-order the rate constant ranged from 0.031 to 0.095 VS (1-n) ×day -1 . The resulting models were validated by comparing statistical parameters. Evaluation of the models showed that, in the aerated reactors, the n-order models (less than 1) successfully estimated the VS changes. In the non-aeration reactor, for the second-order model good agreement was achieved between the simulated and actual quantities of VS. Also, half-life time provided a useful criterion for the estimation of expected time for completion of different phases of composting.
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Arab, Golnaz; Razaviarani, Vahid; Sheng, Zhiya; Liu, Yang; McCartney, Daryl
2017-10-01
Linkage between composting reactor performance and microbial community dynamics was investigated during co-composting of digestate and fresh feedstock (organic fraction of municipal solid waste) using 25L reactors. Previously, the relationship between composting performance and various physicochemical parameters were reported in Part I of the study (Arab and McCartney, 2017). Three digestate to fresh feedstock ratios (0, 40, and 100%; wet weight basis) were selected for analysis of microbial community dynamics. The 40% ratio was selected because it was found to perform the best (Arab and McCartney, 2017). Illumina sequencing results revealed that the reactor with a greater composting performance (higher organic matter degradation and higher heat generation; 40% ratio) was associated with higher microbial diversity. Two specific bacterial orders that might result in higher performance were Thermoactinomycetaceae and Actinomycetales with a higher sequence abundance during thermophilic composting phase and during the maturing composting phase, respectively. Galactomyces, Pichia, Chaetomium, and Acremonium were the four fungal genera that are probably also involved in higher organic matter degradation in the reactor with better performance. The redundancy analysis (RDA) biplot indicated that among the studied environmental variables, temperature, total ammonia nitrogen and nitrate concentration accounted for much of the major shifts in microbial sequence abundance during the co-composting process. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
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Gautam, S. P.; Bundela, P. S.; Pandey, A. K.; Jamaluddin; Awasthi, M. K.; Sarsaiya, S.
2012-01-01
Municipal solid waste contains high amounts of cellulose, which is an ideal organic waste for the growth of most of microorganism as well as composting by potential microbes. In the present study, Congo red test was performed for screening of microorganism, and, after selecting a potential strains, it was further used for biodegradation of organic municipal solid waste. Forty nine out of the 250 different microbes tested (165 belong to fungi and 85 to bacteria) produced cellulase enzyme and among these Trichoderma viride was found to be a potential strain in the secondary screening. During the biodegradation of organic waste, after 60 days, the average weight losses were 20.10% in the plates and 33.35% in the piles. There was an increase in pH until 20 days. pH however, stabilized after 30 days in the piles. Temperature also stabilized as the composting process progressed in the piles. The high temperature continued until 30 days of decomposition, after which the temperature dropped to 40°C and below during the maturation. Good quality compost was obtained in 60 days. PMID:22518141
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Co-composting of two-phase olive-mill pomace and poultry manure with tomato harvest stalks.
Sülük, Kemal; Tosun, İsmail; Ekinci, Kamil
2017-04-01
In this study, two-phase olive-mill pomace with poultry manure and chopped tomato harvest stalks were composted at different initial carbon/nitrogen (C/N) ratios with fixed free air space of 35%. Composting experiment was carried out in the 15 aerobic reactors made of stainless steel and was monitored for 28 days. During the composting process, temperature, moisture content, organic matter (OM), pH, electrical conductivity, oxygen and carbon dioxide concentrations, total carbon, total nitrogen, ammonium nitrogen ([Formula: see text]), nitrate nitrogen ([Formula: see text]), and total phosphorus were monitored. Compost mass and volume changes were determined at the beginning, during remixings, and at the end of composting. While the stabilization period took less time for the mixtures containing a high amount of poultry manure, the mixtures having the high portion of two-phase olive-mill pomace took a longer time due to the structure of olive stone and its lignin content. Dry matter loss (range: 18.1-34.0%.) in the mixtures increased with an increase in the share of poultry manure and tomato stalks in the initial mixture. OM loss (range: 21.7-46.1%) for tomato stalks (measured separately) during composting increased due to an increase in the ratio of poultry manure in the initial mixtures.
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Joseph, Stephen; Kammann, Claudia I; Shepherd, Jessica G; Conte, Pellegrino; Schmidt, Hans-Peter; Hagemann, Nikolas; Rich, Anne M; Marjo, Christopher E; Allen, Jessica; Munroe, Paul; Mitchell, David R G; Donne, Scott; Spokas, Kurt; Graber, Ellen R
2018-03-15
Recent studies have demonstrated the importance of the nutrient status of biochar and soils prior to its inclusion in particular agricultural systems. Pre-treatment of nutrient-reactive biochar, where nutrients are loaded into pores and onto surfaces, gives improved yield outcomes compared to untreated biochar. In this study we have used a wide selection of spectroscopic and microscopic techniques to investigate the mechanisms of nutrient retention in a high temperature wood biochar, which had negative effects on Chenopodium quinoa above ground biomass yield when applied to the system without prior nutrient loading, but positive effects when applied after composting. We have compared non-composted biochar (BC) with composted biochar (BCC) to elucidate the differences which may have led to these results. The results of our investigation provide evidence for a complex series of reactions during composting, where dissolved nutrients are first taken up into biochar pores along a concentration gradient and through capillary action, followed by surface sorption and retention processes which block biochar pores and result in deposition of a nutrient-rich organomineral (plaque) layer. The lack of such pretreatment in the BC samples would render it reactive towards nutrients in a soil-fertilizer system, making it a competitor for, rather than provider of, nutrients for plant growth. Copyright © 2017 Elsevier B.V. All rights reserved.
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Cabrera, G L; Rodriguez, D M; Maruri, A B
1999-05-19
The production of compost is one of the alternatives for the disposal of non-hazardous solid wastes. Compost is used in agriculture and gardening as fertilizer. In the State of Queretaro, Mexico, there is a project to produce compost from the municipal garbage which could be used as a fertilizer. The presence of mutagenic compounds in the compost could be a major disadvantage for the selection of this alternative. For the above reason, this study was initiated as a pilot project to determine the potential mutagenic activity in the compost using three plant bioassays: Tradescantia-micronucleus (Trad-MCN), Tradescantia stamen hair mutations (Trad-SHM) and Allium root anaphase aberrations (AL-RAA). Compost was produced using both aerobic and anaerobic processes from either organic waste (from the residential area) or from the total components of the municipal garbage. Extractions from the compost were done using distilled water and organic solvents and shaking the sample for about 12 h under relatively low temperatures (15-20 degrees C). Plant cuttings of Tradescantia or the roots of Allium were treated by submerging them in the extracts. Three replicates of each sample were analyzed in each one of the three bioassays. As expected the samples of compost from the total garbage showed a higher genetoxicity than those from organic waste. In conclusion, there are some substances present in the compost capable of inducing genotoxicity in the plant assays and therefore there must be some restrictions for its use as a fertilizer. Copyright 1999 Elsevier Science B.V.
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Resource recovery of food waste through continuous thermophilic in-vessel composting.
Waqas, Mohammad; Almeelbi, Talal; Nizami, Abdul-Sattar
2018-02-01
In the Kingdom of Saudi Arabia (KSA) and Gulf region, a very small amount of municipal solid waste (MSW) is treated for compost production. The produced compost through traditional methods of compost piles and trenches does not coincide with the international standards of compost quality. Therefore, in this study, a continuous thermophilic composting (CTC) method is introduced as a novel and efficient technique for treating food waste into a quality compost in a short period of time. The quality of the compost was examined by degradation rates of organic matter (OM), changes in total carbon (TC), ash contents, pH, dynamics in ammonium nitrogen (NH 4 -N) and nitrate nitrogen (NO 3 -N), and nitrification index (NI). The results showed that thermophilic treatment at 60 °C increased the pH of the substrate and promoted degradation and mineralization process. After 30 days of composting, the degree of OM degradation was increased by 43.26 and 19.66%, NH 4 -N by 65.22 and 25.23%, and NO 3 -N by 44.76 and 40.05% as compared to runs treated at 25 and 40 °C, respectively. The stability of the compost was attained after 30 to 45 days with quality better than the compost that was stabilized after 60 days of the experiment under mesophilic treatment (25 °C). The final compost also showed stability at room temperature, confirming the rapid degradation and maturation of food waste after thermophilic treatment. Moreover, the quality of produced compost is in line with the compost quality standard of United States (US), California, Germany, and Austria. Hence, CTC can be implemented as a novel method for rapid decomposition of food waste into a stable organic fertilizer in the given hot climatic conditions of KSA and other Gulf countries with a total net saving of around US $70.72 million per year.
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Evaluation of Effective Microorganisms on home scale organic waste composting.
Fan, Yee Van; Lee, Chew Tin; Klemeš, Jiří Jaromír; Chua, Lee Suan; Sarmidi, Mohamad Roji; Leow, Chee Woh
2018-06-15
Home composting can be an effective way to reduce the volume of municipal solid waste. The aim of this study is to evaluate the effect of Effective Microorganism™ (EM) for the home scale co-composting of food waste, rice bran and dried leaves. A general consensus is lacking regarding the efficiency of inoculation composting. Home scale composting was carried out with and without EM (control) to identify the roles of EM. The composting parameters for both trials showed a similar trend of changes during the decomposition. As assayed by Fourier Transform Infrared Spectroscopy (FTIR), the functional group of humic acid was initially dominated by aliphatic structure but was dominated by the aromatic in the final compost. The EM compost has a sharper peak of aromatic CC bond presenting a better degree of humification. Compost with EM achieved a slightly higher temperature at the early stage, with foul odour suppressed, enhanced humification process and a greater fat reduction (73%). No significant difference was found for the final composts inoculated with and without EM. The properties included pH (∼7), electric conductivity (∼2), carbon-to-nitrogen ratio (C: N < 14), colour (dark brown), odour (earthy smell), germination index (>100%), humic acid content (4.5-4.8%) and pathogen content (no Salmonella, <1000 Most Probable Number/g E. coli). All samples were well matured within 2 months. The potassium and phosphate contents in both cases were similar however the EM compost has a higher nitrogen content (+1.5%). The overall results suggested the positive effect provided by EM notably in odour control and humification. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Optimum moisture levels for biodegradation of mortality composting envelope materials.
Ahn, H K; Richard, T L; Glanville, T D
2008-01-01
Moisture affects the physical and biological properties of compost and other solid-state fermentation matrices. Aerobic microbial systems experience different respiration rates (oxygen uptake and CO2 evolution) as a function of moisture content and material type. In this study the microbial respiration rates of 12 mortality composting envelope materials were measured by a pressure sensor method at six different moisture levels. A wide range of respiration (1.6-94.2mg O2/g VS-day) rates were observed for different materials, with alfalfa hay, silage, oat straw, and turkey litter having the highest values. These four envelope materials may be particularly suitable for improving internal temperature and pathogen destruction rates for disease-related mortality composting. Optimum moisture content was determined based on measurements across a range that spans the maximum respiration rate. The optimum moisture content of each material was observed near water holding capacity, which ranged from near 60% to over 80% on a wet basis for all materials except a highly stabilized soil compost blend (optimum around 25% w.b.). The implications of the results for moisture management and process control strategies during mortality composting are discussed.
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Carbon monoxide from composting due to thermal oxidation of biomass.
Hellebrand, H J; Schade, G W
2008-01-01
Emissions of carbon monoxide (CO) were observed from decomposing organic wastes and litter under laboratory, pilot composting plant, and natural conditions. Field studies included air from inside a compost heap of about 200 m3, emissions from composting of livestock wastes at a biologically operating farm, and leaf litter pile air samples. The concentration of CO was up to 120 micromol mol(-1) in the compost piles of green waste, and up to 10 micromol mol(-1) in flux chambers above livestock waste windrow composts. The mean CO flux rates were approximately 20 mg CO m(-2) h(-1) for compost heaps of green waste, and varied from 30 to 100 mg CO m(-2) h(-1) for fresh dung windrows. Laboratory studies using a temperature and ventilation-controlled substrate container were performed to elucidate the origin of CO, and included hay samples of fixed moisture content at temperatures between 5 and 65 degrees C, including nonsterilized as well as sterilized samples. The concentration of CO was up to 160 micromol mol(-1) in these experiments, and Arrhenius-type plot analyses resulted in activation energies of 65 kJ mol(-1) for thermochemically produced CO from the nonsterilized compost substrate. Sterilized samples showed dramatically reduced CO2 but virtually unchanged CO emissions, albeit at a slightly lower activation energy, likely a result of the high-temperature sterilization. Though globally and regionally these CO emissions are only a minor source, thermochemically produced CO emissions might affect local air quality in and near composting facilities.
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Huang, Yu-Lian; Sun, Zhao-Yong; Zhong, Xiao-Zhong; Wang, Ting-Ting; Tan, Li; Tang, Yue-Qin; Kida, Kenji
2017-03-01
Digested residue remained at the end of a process for the production of fuel ethanol and methane from kitchen garbage. To develop a zero-emission process, the compostability of the digested residue was assessed to obtain an added-value fertilizer. Composting of the digested residue by adding matured compost and a bulking agent was performed using a lab-scale composting reactor. The composting process showed that volatile total solid (VTS) degradation mainly occurred during the first 13days, and the highest VTS degradation efficiency was about 27% at the end. The raw material was not suitable as a fertilizer due to its high NH 4 + and volatile fatty acids (VFAs) concentration. However, the composting process produced remarkable results; the physicochemical properties indicated that highly matured compost was obtained within 62days of the composting process, and the final N concentration, NO 3 - concentration, and the germination index (GI) at the end of the composting process was 16.4gkg -1 -TS, 9.7gkg -1 -TS, and 151%, respectively. Real-time quantitative PCR (qPCR) analysis of ammonia oxidizers indicated that the occurrence of nitrification during the composting of digested residue was attributed to the activity of ammonia-oxidizing bacteria (AOB). Copyright © 2017 Elsevier Ltd. All rights reserved.
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Comparing composts formed by different technological processing
NASA Astrophysics Data System (ADS)
Lyckova, B.; Mudrunka, J.; Kucerova, R.; Glogarova, V.
2017-10-01
The presented article compares quality of composts which were formed by different technological processes. The subject to comparison was a compost which was created in a closed fermenter where ideal conditions for decomposition and organic substances conversion were ensured, with compost which was produced in an open box of community composting. The created composts were analysed to determine whether it is more important for the final compost to comply with the composting conditions or better sorting of raw materials needed for compost production. The results of the carried out experiments showed that quality of the resulting compost cannot be determined unequivocally.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Chefetz, B.; Yona Chen; Hadar, Y.
Composting of municipal solid waste (MSW) was studied in an attempt to elaborate transformations of organic matter (OM) during the process and define parameters for the degree of maturity of the product. Composting was performed in 1-m{sup 3} plastic boxes and the following parameters were measured in 13 samples during 132 d of composting: temperature, C/N ratio, ash content, humic substance contents, and fractions (humic acid, fulvic acid, and nonbumic fraction-HA, FA and NHF, respectively). Spectroscopic methods (CPMAS {sup 13}C-NMR, DRIFT) were used to study the chemical composition of the OM. A bioassay based on growth of cucumber (Cucumis satifusmore » L. cv. Dlila) plants was correlated to other parameters. The C/N ratio and ash content showed a typical high rate of change during the first 60 d and reached a plateau thereafter. The HA content increased to a maximum at 112 d, corresponding to the highest plant dry weight and highest 1650/1560 (cm{sup {minus}1}/cm{sup {minus}1}) peak ratios calculated from DRIFT spectra. {sup 13}C-NMR and DRIFT spectra of samples taken from the composting MSW during the process showed that the residual OM contained an increasing level of aromatic structures. Plant-growth bioassay, HA content, and the DRIFT spectra indicated that MSW compost described in this study, stabilized and achieved maturity after about 110 d. 31 refs., 8 figs., 2 tabs.« less
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Co-composting of vegetable wastes and carton: Effect of carton composition and parameter variations.
Rawoteea, Soonita Anjeena; Mudhoo, Ackmez; Kumar, Sunil
2017-03-01
The aim of the study was to investigate the effects of carton in the composting process of mixed vegetable wastes using an experimental composter of capacity 80L. Three different mixes were set-up (Mixes 1, 2 and 3) which consisted of vegetable wastes, 2.0kg paper and bulking agents, vegetable wastes, 1.5kg carton and bulking agents, vegetable wastes, 4.5kg carton and bulking agents, respectively. Temperature evolution, pH trends, moisture levels, respiration rates, percentage volatile solids and electrical conductivity were monitored for a period of 50days. The system remained under thermophilic conditions for a very short period due to the small size of the reactor. The three mixes did not exceed a temperature of 55°C, where sanitization takes place by the destruction of pathogens. The highest peak of CO 2 evolution was observed in Mix 2 indicating that maximum microbial degradation took place in that mix. Copyright © 2016. Published by Elsevier Ltd.
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Zhu, Nengwu
2006-10-01
Pilot composting experiments of swine manure with corncob were conducted to evaluate the performance of the aerated static bin composting system. Effects of temperature control (60 and 70 degrees C) and moisture content (70% and 80%) were monitored on the composting by measuring physical and chemical indexes. The results showed that (1) the composting system could destroy pathogens, converted nitrogen from unstable ammonia to stable organic forms, and reduced the volume of waste; (2) significant difference of NH(4)(+)-N (P(12) = 0.074), and (NO(3)(-) + NO(2)(-))-N (P(12) = 0.085) was found between the temperature control treatments; (3) anaerobic reaction in the treatment with 80% moisture content resulted in significant difference of pH (P(23) = 0.006), total organic matter (P(23) = 0.003), and germination index (P(23) = 0.040) between 70% and 80%. Therefore, the optimum initial moisture content was less than 80% with the composting of swine manure and corncob by using the composting system.
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Gou, Changlong; Wang, Yuqiong; Zhang, Xiqing; Lou, Yujie; Gao, Yunhang
2017-11-01
The objective was to determine the effects of psychrotrophic-thermophilic complex microbial agent (PTCMA) comprised of a psychrotrophic bacterium consortium (PBC) and a thermophilic cellulolytic fungi consortium (TCFC), on composting in a cold climate. Mixtures of dairy manure and rice straw were inoculated with PTCMA, PBC, TCFC and sterile water (control) and composted at an initial ambient temperatures of -2 to 5°C. In compost piles inoculated with PBC or PTCMA, temperatures reached the thermophilic phase (>55°C) faster (8-11d) than piles inoculated with TCFC or control. Furthermore, compost inoculated with TCFC or PTCMA had greater decreases in total organic carbon and carbon-to-nitrogen ratios, as well as significant increases in total nitrogen, degradation of cellulose and lignin and germination index than PBC inoculation or Control compost. Consequently, inoculation with both (i.e. PTCMA) accelerated the onset and promoted maturity of composting under cold-climate conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Thermal hydrolysis (TDH) as a pretreatment method for the digestion of organic waste.
Schieder, D; Schneider, R; Bischof, F
2000-01-01
The recycling concept under consideration is based on the process of Thermal Hydrolysis (TDH) followed by an anaerobic digestion. By increasing pressure and temperature the organic part of the waste is split up in a first step into short-chain fragments that are biologically well suited for microorganisms. The following fermentation runs much faster and more complete than in conventional digestion processes and the biogas yield is increased. Left is just a small amount of a solid residue that can be easily dewatered and utilized as surrogate fuel for incineration or as compost additive. The thermal hydrolysis process allows a complete energy recovery from organic waste. During the total procedure more energy sources are produced than are needed for running the plant. The procedure is especially suited for wet organic waste and biosolids that are difficult to compost, such as food scraps, biological waste from compact residential areas and sewage sludge. As a complete disinfection is granted due to the process temperatures the procedure is also suited for carcasses.
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Assessment of co-composting process with high load of an inorganic industrial waste.
Soares, Micaela A R; Quina, Margarida J; Reis, Marco S; Quinta-Ferreira, Rosa
2017-01-01
This study aims to investigate the co-composting of an inorganic industrial waste (eggshell - ES) in very high levels (up to 60% w/w). Since composting is a process in which solid, liquid and gaseous phases interact in a very complex way, there is a need to shed light on statistical tools that can unravel the main relationships structuring the variability associated to this process. In this study, PCA and data visualisation were used with that purpose. The co-composting tests were designed with increasing quantities of ES (0, 10, 20, 30 and 60%ES w/w) mixed with industrial potato peel and rice husks. Principal component analysis showed that physical properties like free air space, bulk density and moisture are the most relevant variables for explaining the variability due to ES content. On the other hand, variability in time dynamics is mostly driven by some chemical and phytoxicological parameters, such as organic matter decay and nitrate content. Higher ES incorporation (60% ES) enhanced the initial biological activity of the mixture, but the higher bulk density and lower water holding capacity had a negative effect on the aerobic biological activity as the process evolved. Nevertheless, pathogen-killing temperatures (>70°C for 11h) were attained. All the final products obtained after 90days were stable and non-phytotoxic. This work proved that valorisation of high amounts of eggshell by co-composting is feasible, but prone to be influenced by the physical properties of the mixtures. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Huang, Yi-Mei; Liu, Xue-Ling; Jiang, Ji-Shao; Huang, Hua; Liu, Dong
2012-08-01
Taking substrates swine manure and wheat straw (fresh mass ratio 10.5:1) as the control (PMW), a composting experiment was conducted in a self-made aerated static composting bin to study the effects of adding 8% grape seed (treatment PMW + G) on the succession of microbial community and the transformation of carbon and nitrogen in the substrates during the composting. Seven samples were collected from each treatment, according to the temperature of the compost during the 30 d composting period. The microbial population and physiological groups were determined, and the NH4(+)-N, NO3(-)-N, organic N, and organic C concentrations in the compost were measured. Grape seed addition induced a slight increase of bacterial count and a significant increase of actinomycetes count, but decreased the fungal count significantly. Grape seed addition also decreased the ratio of bacteria to actinomycetes and the counts of ammonifiers and denitrifiers, but increased the counts of nitrifiers, N-fixing bacteria, and cellulose-decomposing microorganisms. The contents of NH4(+)-N and organic C decreased, while that of NO3(-)-N increased obviously. The NO3(-)-N content in the compost was positively correlated with the actinomycetes count. During composting, the compost temperature in treatment PMW + G increased more rapidly, and remained steady in thermophilic phase, while the water content changed little, which provided a stable and higher population of actinomycetes and nitrifiers in thermophilic phase, being beneficial to the increase of compost nitrate N.
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Green house gas emissions from composting and mechanical biological treatment.
Amlinger, Florian; Peyr, Stefan; Cuhls, Carsten
2008-02-01
In order to carry out life-cycle assessments as a basis for far-reaching decisions about environmentally sustainable waste treatment, it is important that the input data be reliable and sound. A comparison of the potential greenhouse gas (GHG) emissions associated with each solid waste treatment option is essential. This paper addresses GHG emissions from controlled composting processes. Some important methodological prerequisites for proper measurement and data interpretation are described, and a common scale and dimension of emission data are proposed so that data from different studies can be compared. A range of emission factors associated with home composting, open windrow composting, encapsulated composting systems with waste air treatment and mechanical biological waste treatment (MBT) are presented from our own investigations as well as from the literature. The composition of source materials along with process management issues such as aeration, mechanical agitation, moisture control and temperature regime are the most important factors controlling methane (CH4), nitrous oxide (N2O) and ammoniac (NH3) emissions. If ammoniac is not stripped during the initial rotting phase or eliminated by acid scrubber systems, biofiltration of waste air provides only limited GHG mitigation, since additional N2O may be synthesized during the oxidation of NH3, and only a small amount of CH4 degradation occurs in the biofilter. It is estimated that composting contributes very little to national GHG inventories generating only 0.01-0.06% of global emissions. This analysis does not include emissions from preceding or post-treatment activities (such as collection, transport, energy consumption during processing and land spreading), so that for a full emissions account, emissions from these activities would need to be added to an analysis.
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The effect of composting on the persistence of four ionophores in dairy manure and poultry litter.
Arikan, Osman A; Mulbry, Walter; Rice, Clifford
2016-08-01
Manure composting is a well-described approach for stabilization of nutrients and reduction of pathogens and odors. Although composting studies have shown that thermophilic temperatures and aerobic conditions can increase removal rates of selected antibiotics, comparable information is lacking for many other compounds in untreated or composted manure. The objective of this study was to determine the relative effectiveness of composting conditions to reduce concentrations of four widely used ionophore feed supplements in dairy manure and poultry litter. Replicate aliquots of fresh poultry litter and dairy manure were amended with monensin, lasalocid, salinomycin, or amprolium to 10mgkg(-1)DW. Non-amended and amended dairy manure and poultry litter aliquots were incubated at 22, 45, 55, or 65°C under moist, aerobic conditions. Residue concentrations were determined from aliquots removed after 1, 2, 4, 6, 8, and 12weeks. Results suggest that the effectiveness of composting for contaminant reduction is compound and matrix specific. Composting temperatures were not any more effective than ambient temperature in increasing the rate or extent of monensin removal in either poultry litter or dairy manure. Composting was effective for lasalocid removal in poultry litter, but is likely to be too slow to be useful in practice (8-12weeks at 65°C for >90% residue removal). Composting was effective for amprolium removal from poultry litter and salinomycin in dairy manure but both required 4-6weeks for >90% removal. However, composting did not increase the removal rates or salinomycin in poultry litter or the removal rates of lasalocid or amprolium in dairy manure. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Study and assessment of segregated biowaste composting: The case study of Attica municipalities.
Malamis, D; Bourka, A; Stamatopoulou, Ε; Moustakas, K; Skiadi, O; Loizidou, M
2017-12-01
This work aims to assess the operation of the first large scale segregated biowaste composting scheme in Greece to divert Household Food Waste (HFW) from landfill and produce a material which can be recovered and used as compost. The source separation and collection of HFW was deployed in selected areas in Attica Region serving about 3700 households. Sorted HFW is collected & transported to the Mechanical and Biological Treatment (MBT) plant in Attica Region that has been designed to produce Compost Like Output (CLO) from mixed MSW. The MBT facility has been adjusted in order to receive and treat aerobically HFW mixed with shredded green waste in a dedicated composting tunnel. The composting process was monitored against temperature, moisture and oxygen content indicating that the biological conditions are sufficiently developed. The product quality was examined and assessed against the quality specifications of EU End of Waste Criteria for biowaste subjected to composting aiming to specify whether the HFW that has undergone recovery ceases to be waste and can be classified as compost. More specifically, the heavy metals concentrations (Cr, Cu, Ni, Cd, Pb, Zn and Hg) are within the set limits and much lower compared to the CLO material that currently is being produced at the MBT plant. In regard to the hygienic requirements of the product it has been found that the process conditions result in a pathogen free material (i.e. E. Coli and Salmonella) which does not favor the growth of viable weeds and plant propagules, while it acquires sufficient organic matter content for soil fertilization. Noticeable physical impurities (mainly fractions of glass) have been detected exceeding the quality control threshold limit of 0.5% w/w (plastics, metals and glass). The latter is related to the missorted materials and to the limited pre-treatment configurations prior to composting. The above findings indicate that effective source separation of biowaste is prerequisite for good quality production and marketing of compost and special consideration should be made to minimize glass impurities prior composting (i.e. awareness raising and pretreatment stage). Therefore, it is feasible to gradually replace the production of questionable quality CLO in MBTs with biowaste compost which is in line with the required quality control standards especially when heavy metals concentrations is concerned. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Hachicha, Ridha; Rekik, Olfa; Hachicha, Salma; Ferchichi, Mounir; Woodward, Steve; Moncef, Nasri; Cegarra, Juan; Mechichi, Tahar
2012-07-01
The co-composting of spent coffee grounds, olive mill wastewater sludge and poultry manure was investigated on a semi-industrial scale. In order to reduce the toxicity of the phenolic fraction and to improve the degree of composting humification, composts were inoculated with the white-rot fungus Trametes versicolor in the early stages of the maturation phase. During composting, a range of physico-chemical parameters (temperature and both organic matter and C/N reduction), total organic carbon, total nitrogen, elemental composition, lignin degradation and spectroscopic characteristics of the humic acids (HAs) were determined; impacts of the composting process on germination index of Hordeum vulgare and Lactuca sativa were assessed. The coffee waste proved to be a highly compostable feedstock, resulting in mature final compost with a germination index of 120% in less than 5 months composting. In addition, inoculation with T. versicolor led to a greater degree of aromatization of HA than in the control pile. Moreover, in the inoculated mixture, lignin degradation was three times greater and HA increased by 30% (P<0.05), compared to the control pile. In the T. versicolor inoculated mixture, the averages of C and N were significantly enhanced in the HA molecules (P<0.05), by 26% and 22%, respectively. This improvement in the degree of humification was confirmed by the ratio of optical densities of HA solutions at 465 and 665 nm which was lower for HA from the treated mixture (4.5) than that from the control pile (5.4). Copyright © 2012 Elsevier Ltd. All rights reserved.
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Degradation of foot-and-mouth disease virus during composting of infected pig carcasses
Guan, J.; Chan, M.; Grenier, C.; Brooks, B.W.; Spencer, J.L.; Kranendonk, C.; Copps, J.; Clavijo, A.
2010-01-01
The objective of this study was to investigate the inactivation and degradation of foot-and-mouth disease (FMD) virus during composting of infected pig carcasses as measured by virus isolation in tissue culture and by real-time reverse transcriptase polymerase chain reaction (RRT-PCR). Three FMD-infected pig carcasses were composted in a mixture of chicken manure and wood shavings in a biocontainment level 3 facility. Compost temperatures had reached 50°C and 70°C by days 10 and 19, respectively. Under these conditions, FMD virus was inactivated in specimens in compost by day 10 and the viral RNA was degraded in skin and internal organ tissues by day 21. In comparison, at ambient temperatures close to 20°C, FMD virus survived to day 10 in the skin tissue specimen from the pig that had the highest initial level of viral RNA in its tissues and the viral RNA persisted to day 21. Similarly, beta-actin mRNA, tested as a PCR control, persisted to day 21 in specimens held at ambient temperatures, but it was degraded in the remnants of tissues recovered from compost on day 21. Results from this study provide evidence that composting could be used for safe disposal of pig carcasses infected with FMD virus. PMID:20357957
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Tashiro, Yukihiro; Matsumoto, Hiroko; Miyamoto, Hirokuni; Okugawa, Yuki; Pramod, Poudel; Miyamoto, Hisashi; Sakai, Kenji
2013-10-01
We investigated L-lactic acid production in static batch fermentation of kitchen refuse using a bacterial consortium from marine-animal-resource (MAR) composts at temperatures ranging from 30 to 65 °C. At relatively low temperatures butyric acid accumulated, whereas at higher temperatures L-lactic acid was produced. In particular, fermentation at 50 °C produced 34.5 g L(-1) L-lactic acid with 90% lactic acid selectivity and 100% optical purity. Denaturing gradient gel electrophoresis indicated that dominant bacteria present in the original MAR composts diminished rapidly and Bacillus coagulans strains became the dominant contributors to L-lactic acid production at 45, 50 and 55 °C. This is the first report of the achievement of 100% optical purity of L-lactic acid using a bacterial consortium. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Composting of empty fruit bunches in the tower composter - effect of air intake holes
NASA Astrophysics Data System (ADS)
Irvan; Husaini, T.; Trisakti, B.; Batubara, F.; Daimon, H.
2018-02-01
The process of composting empty fruit bunches (EFB) by mixing with activated liquid organic fertilizer (ALOF) is an alternative utilization of solid waste generated from palm oil mill. This study aims to find composting techniques of EFB and to obtain degradation data of composting EFB by varying the air intake holes to produce good quality compost. Composting process was carried out by tearing the EFB into four shreds, then put into the tower composter while adding ALOF until it reached the optimum moisture content of 55 -65%. During the composting process, we maintained moisture content at optimum conditions by adding ALOF. Variations of air intake holes area to the outer surface area of the composter are 0/44.314; 72.39/44.314 and 144.78/44.314 (cm2/cm2). Composting is carried out for forty days, however, based on the result, compost began to mature on the 10th day. The results revealed that there was an influence of air intake holes to the composting process. The best degradation of EFB was obtained on the variation of air intake holes 72.39/44.314 (cm2/cm2), pH 8.1, moisture content 79.14%, water holding capacity 60%, electrical conductivity 4.725 dS/m and C/N ratio 20.97.
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Duan, Manli; Gu, Jie; Wang, Xiaojuan; Li, Yang; Zhang, Sheqi; Yin, Yanan; Zhang, Ranran
2018-01-01
Genetically modified (GM) cotton production generates a large yield of stalks and their disposal is difficult. In order to study the feasibility of using GM cotton stalks for composting and the changes that occur in antibiotic resistance genes (ARGs) during composting, we supplemented pig manure with GM or non-GM cotton stalks during composting and we compared their effects on the absolute abundances (AA) of intI1, intI2, and ARGs under the two treatments. The compost was mature after processing based on the germination index and C/N ratio. After composting, the AAs of ARGs, intI1, and intI2 were reduced by 41.7% and 45.0% in the non-GM and GM treatments, respectively. The ARG profiles were affected significantly by temperature and ammonia nitrogen. In addition, excluding tetC, GM cotton stalks had no significant effects on ARGs, intI1, and intI2 compared with the non-GM treatment (p < 0.05). Thus, similar to non-GM cotton stalks, GM cotton stalks can be used for aerobic composting with livestock manure, and the AAs of ARGs can be reduced. Furthermore, the results of this study provide a theoretical basis for the harmless utilization of GM cotton stalks. Copyright © 2017 Elsevier Inc. All rights reserved.
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The Compost Pile Meets the 1990's.
ERIC Educational Resources Information Center
Paddock, Todd
1991-01-01
Advocates composting as a valuable alternative to the landfill for waste management. As much as two-thirds of garbage can be composted, and the process has become more cost effective. Some challenges to composting are producing a compost product that will sell and dealing with the odor created by the process. (KS)
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Characterization of a soil amendment derived from co-composting of agricultural wastes and biochar
NASA Astrophysics Data System (ADS)
Curaqueo, Gustavo; Ángel Sánchez-Monedero, Miguel; Meier, Sebastián; Medina, Jorge; Panichini, Marcelo; Borie, Fernando; Navia, Rodrigo
2016-04-01
The aim of this study was to characterize a compost blend prepared from sheep manure and oat straw in a co-composting process enriched with oat husk biochar (BC). For this, a co-composting trial was carried out in rotatories bins of 200 L capacity. Three mixtures (piles) were assayed: BC0: sheep manure (SM) 65% w/w with 35% w/w oat straw (OS) and no biochar; BC5: SM 62.5% w/w, 32.5% of OS and 5% of BC and BC10: SM 60% w/w, 30% of OS and 10% of BC. The piles were turned 3 times per week in the first week, and then once a week until the end of the composting process (140 days). The temperature and humidity of the piles were monitored continually and the humidity was maintained in a range from 55% to 65%. The maturity of final compost was evaluated by FTIR and Solvita Test analysis. At the same time a chemical characterization including macro and micro nutrient for each compost was performed and the compost phytotoxic effect was evaluated by a germination test using aqueous extract over lettuce, radish and wheat seeds. FTIR analysis showed bands attributed to aromatic C=C, C=O stretching of amide groups, quinone C=O and/or C=O of H-bonded conjugated ketones (1640 cm-1) which are typical in biological stabilized composts and compost with high concentration of highly aromatic materials such as biochar, which seems to become relatively more intense specially in BC10 treatment. Both composts were characterized by a Solvita maturity index of 7, reflecting an adequate degree of maturation. The CO2 emission was lower in the piles enriched with BC compared to control treatment without BC. In the same way, NH3 index was 5 for all the treatments indicating a null NH3 emission. In this respect, a decrease in the N-NH4 content was related with the use of BC which indicate that BC could reduce N-losses during composting favoring nitrification process. Chemical characterization showed pH values higher than 8 for all piles and EC ranged from 8.6 to 14.7 dS cm-1. The Total N and P contents increased in BC10 treatment, while the K contents were similar in all treatments as well as C/N ratio (around 15). The organic matter content was BC10>BC5>BC0 and the dissolved organic C content was lower than 8.3 g kg-1 for all piles confirming the maturity of compost. The germination test showed a non-toxic effect of all amendments in the species assayed obtaining a germination index between 55% and 80.7% indicating maturity of the amendments evaluated. Our results indicated that the combined use of agricultural wastes and biochar by mean of a co-composting process is a suitable option for generating good quality amendments for improving soil condition and optimizing nutrient cycling at farm scale. Financial support for this research was provided by the National Commission for Scientific and Technological Research through FONDECYT 11140508 Project
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Gong, Xiaoqiang; Li, Suyan; Sun, Xiangyang; Zhang, Lu; Zhang, Tao; Wei, Le
2017-04-01
Green waste was separately inoculated on day 0 and day 14 with either Trametes versicolor or Phanerochaete chrysosporium to determine their effects on composting time and compost quality. Inoculation with T. versicolor and P. chrysosporium caused more rapid and higher increases in compost temperatures, increased the duration of the thermophilic temperature stage, and reduced the maturity time. Inoculation with T. versicolor and P. chrysosporium greatly increased the quality of the final composts in terms of pH, electrical conductivity, organic matter concentration, C/N ratio, germination index, and nutrient content. Inoculation with T. versicolor and P. chrysosporium also significantly increased the degradation of lignin by 7.1% and 8.2%, respectively, and increased the degradation of cellulose by 10.6% and 13.6%, respectively.
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Monitoring of biopile composting of oily sludge.
Kriipsalu, Mait; Nammari, Diauddin
2010-05-01
This paper describes a bioreactor set-up used to simulate degradation of petroleum hydrocarbons in a static biopile. The large-scale test was performed in a 28 m(3) custom-designed reactor. Oily sludge (40% by weight, having 7% dry matter [DM], and hydrocarbons C(10)-C(40) 160,000 mg kg(-1) DM) was mixed with organic-rich amendments - mature oil-compost (40%) and garden waste compost (20%). Within the reactor, the temperature and soil gases were monitored continuously during 370 days via 24 measurement points. Also, moisture content was continuously recorded and airflow through compost mix occasionally measured. Three-dimensional ordinary kriging spatial models were created to describe the dynamic variations of temperature, air distribution, and hydrocarbon concentration. There were large temperature differences in horizontal and vertical sections during initial months of composting only. Water content of the mixture was uneven by layers, referring on relocation of moisture due to aeration and condensation. The air distribution through the whole reactor varied largely despite of continuous aeration, while the concentration of O(2) was never reduced less than 1-2% on average. The results showed that composting of sludge using force-aerated static biopile technology was justified during the first 3-4 months, after which the masses could be re-mixed and heaped for further maturation in low-tech compost windrows. After 370 days of treatment, the content of hydrocarbons (C( 10)-C(40)) in the compost mixture was reduced by 68.7%.
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Composting of food wastes: Status and challenges.
Cerda, Alejandra; Artola, Adriana; Font, Xavier; Barrena, Raquel; Gea, Teresa; Sánchez, Antoni
2018-01-01
This review analyses the main challenges of the process of food waste composting and examines the crucial aspects related to the quality of the produced compost. Although recent advances have been made in crucial aspects of the process, such composting microbiology, improvements are needed in process monitoring. Therefore, specific problems related to food waste composting, such as the presence of impurities, are thoroughly analysed in this study. In addition, environmental impacts related to food waste composting, such as emissions of greenhouse gases and odours, are discussed. Finally, the use of food waste compost in soil bioremediation is discussed in detail. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Bijlsma, P B; de Wit, D H; Duindam, J W; Elsinga, G J; Elsinga, W
2013-01-30
This study was aimed to collect data and develop methodologies to determine if and how Dutch biowaste composting plants can meet the microbiological requirements set out in EU-Regulations (EC) 1774/2002 and (EC) 1069/2009, and to provide the European Food and Safety Authority (EFSA) with data and analysis for evaluation of these regulations. We examined twenty plant locations and four types of composting technologies, all with forced aeration and without an anaerobic digestion phase. Raw biowaste, material after sanitation and compost were sampled by spot test analysis according to a standard protocol, and according to an additional protocol with enhanced hygienic precautions. Samples were analyzed for Escherichia coli, Enterococcaceae and Salmonella content. The latter protocol resulted in improved bacterial reductions after sanitation, whereas in compost Enterococcus levels but not E. coli levels increased substantially with both protocols, due to more thermo-resistant regrowth. Salmonella presence in compost coincided with low temperatures and increased levels of E. coli and Enterococcus, absence of Salmonella was associated with absence of E. coli (74%), but not with absence of Enterococcus (17%). In compost, E. coli and Salmonella showed a comparable time-temperature inactivation pattern. A pilot study with co-composting of biowaste and poultry manure indicated a similar inactivation pattern for ESBL-containing bacteria. We conclude that the abundance of Enterococcus in compost is caused by regrowth and not by (re)contamination, and that E. coli is a more reliable indicator species for the absence/presence of Salmonella in compost. Compliance with current EU-regulations concerning biowaste composting can be shown by spot test analysis at all examined plants, provided that adequate hygienic precautions are taken during sampling. Copyright © 2012 Elsevier Ltd. All rights reserved.
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ERIC Educational Resources Information Center
Stanley, Andrew; Turner, Geraldine
2010-01-01
Composting can provide both a means of managing organic waste, and a vehicle to teach Science at all levels of schooling. In response to a local organic waste issue a process has been developed to compost waste from an olive oil press and analyse the resultant compost. In this article, the composting process is described in a manner that can be…
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Maeda, Koki; Morioka, Riki; Osada, Takashi
2009-01-01
To control ammonia (NH(3)) volatilization from the dairy cattle (Bos taurus) manure composting process, a compost pile was covered with mature compost and the gas emissions evaluated using the dynamic chamber system. The peak of NH(3) volatilization observed immediately after piling up of the compost was reduced from 196 to 62 mg/m(3) by covering the compost pile with mature compost. The accumulation of NH(4)-N to the covered mature compost was also observed. Covering and mixing the compost with mature compost had no effect on the microbial community structure. However, over time the microbial community structure changed because of a decrease in easily degradable organic compounds in the compost piles. The availability of volatile fatty acids (VFA) was considered to be important for microbial community structure in the compost. After the VFA had disappeared, the NO(3)-N concentration increased and the cellulose degrading bacteria such as Cytophaga increased in number.
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Zhang, Lu; Sun, Xiangyang
2014-11-01
This research determined whether the two-stage co-composting can be used to convert green waste (GW) into a useful compost. The GW was co-composted with spent mushroom compost (SMC) (at 0%, 35%, and 55%) and biochar (BC) (at 0%, 20%, and 30%). The combined addition of SMC and BC greatly increased the nutrient contents of the compost product and also improved the compost quality in terms of composting temperature, particle-size distribution, free air space, cation exchange capacity, nitrogen transformation, organic matter degradation, humification, element contents, abundance of aerobic heterotrophs, dehydrogenase activity, and toxicity to germinating seeds. The addition of 35% SMC and 20% BC to GW (dry weight % of initial GW) and the two-stage co-composting technology resulted in the production of the highest quality compost product in only 24 days rather than the 90-270 days required with traditional composting. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Compost supplementation with nutrients and microorganisms in composting process.
Sánchez, Óscar J; Ospina, Diego A; Montoya, Sandra
2017-11-01
The composting is an aerobic, microorganism-mediated, solid-state fermentation process by which different organic materials are transformed into more stable compounds. The product obtained is the compost, which contributes to the improvement of physical, chemical and microbiological properties of the soil. However, the compost usage in agriculture is constrained because of its long-time action and reduced supply of nutrients to the crops. To enhance the content of nutrients assimilable by the plants in the compost, its supplementation with nutrients and inoculation with microorganisms have been proposed. The objective of this work was to review the state of the art on compost supplementation with nutrients and the role played by the microorganisms involved (or added) in their transformation during the composting process. The phases of composting are briefly compiled and different strategies for supplementation are analyzed. The utilization of nitrogenous materials and addition of microorganisms fixing nitrogen from the atmosphere or oxidizing ammonia into more assimilable for plants nitrogenous forms are analyzed. Several strategies for nitrogen conservation during composting are presented as well. The supplementation with phosphorus and utilization of microorganisms solubilizing phosphorus and potassium are also discussed. Main groups of microorganisms relevant during the composting process are described as well as most important strategies to identify them. In general, the development of this type of nutrient-enriched bio-inputs requires research and development not only in the supplementation of compost itself, but also in the isolation and identification of microorganisms and genes allowing the degradation and conversion of nitrogenous substances and materials containing potassium and phosphorus present in the feedstocks undergoing the composting process. In this sense, most important research trends and strategies to increase nutrient content in the compost are provided in this work. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Estrada-Bonilla, German A; Lopes, Cintia M; Durrer, Ademir; Alves, Paulo R L; Passaglia, Nicolle; Cardoso, Elke J B N
2017-07-01
Sugarcane processing generates a large quantity of residues, such as filter cake and ashes, which are sometimes composted prior to their amendment in soil. However, important issues still have to be addressed on this subject, such as the description of bacterial succession that occurs throughout the composting process and the possibilities of using phosphate-solubilizing bacteria (PSB) during the process to improve phosphorus (P) availability in the compost end product. Consequently, this study evaluated the bacterial diversity and P dynamics during the composting process when inoculated with Pseudomonas aeruginosa PSBR12 and Bacillus sp. BACBR01. To characterize the bacterial community structure during composting, and to compare PSB-inoculated compost with non-inoculated compost, partial sequencing of the bacterial 16S rRNA gene and sequential P fractionation were used. The data indicated that members of the order Lactobacillales prevailed in the early stages of composting for up to 30 days, mostly due to initial changes in pH and the C/N ratio. This dominant bacterial group was then slowly replaced by Bacillales during a composting process of up to 60 days. In addition, inoculation of PSB reduced the levels of Ca-bound P by 21% and increased the labile organic P fraction. In PSB-inoculated compost, Ca-P compound solubilization occurred concomitantly with an increase of the genus Bacillus. The bacterial succession and the final community is described in compost from sugarcane residues and the possible use of these inoculants to improve P availability in the final compost is validated. Copyright © 2017 Elsevier GmbH. All rights reserved.
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Ogunwande, Gbolabo A; Osunade, James A
2011-01-01
A passive aeration composting study was undertaken to investigate the effects of aeration pipe orientation (PO) and perforation size (PS) on some physico-chemical properties of chicken litter (chicken manure + sawdust) during composting. The experimental set up was a two-factor completely randomised block design with two pipe orientations: horizontal (Ho) and vertical (Ve), and three perforation sizes: 15, 25 and 35 mm diameter. The properties monitored during composting were pile temperature, moisture content (MC), pH, electrical conductivity (EC), total carbon (C(T)), total nitrogen (N(T)) and total phosphorus (P(T)). Moisture level in the piles was periodically replenished to 60% for efficient microbial activities. The results of the study showed that optimum composting conditions (thermophilic temperatures and sanitation requirements) were attained in all the piles. During composting, both PO and PS significantly affected pile temperature, moisture level, pH, C(T) loss and P(T) gain. EC was only affected by PO while N(T) was affected by PS. Neither PO nor PS had a significant effect on the C:N ratio. A vertical pipe was effective for uniform air distribution, hence, uniform composting rate within the composting pile. The final values showed that PO of Ve and PS of 35 mm diameter resulted in the least loss in N(T). The PO of Ho was as effective as Ve in the conservation of C(T) and P(T). Similarly, the three PSs were equally effective in the conservation of C(T) and P(T). In conclusion, the combined effects of PO and PS showed that treatments Ve35 and Ve15 were the most effective in minimizing N(T) loss. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Co-composting of invasive Acacia longifolia with pine bark for horticultural use.
Brito, Luis Miguel; Mourão, Isabel; Coutinho, João; Smith, Stephen R
2015-01-01
The feasibility of commercial-scale co-composting of waste biomass from the control of invasive Acacia species with pine bark waste from the lumber industry, in a blend ratio of 60:40 (v:v), was investigated and compared with previous research on the composting of Acacia without additional feedstock, to determine the potential process and end-product quality benefits of co-composting with bark. Pile temperatures rose rapidly to >70 °C and were maintained at >60 °C for several months. Acacia and bark biomass contained a large fraction of mineralizable organic matter (OM) equivalent to approximately 600 g kg(-1) of initial OM. Bark was more recalcitrant to biodegradation compared with Acacia, which degraded at twice the rate of bark. Therefore, incorporating the bark increased the final amount of compost produced compared with composting Acacia residues without bark. The relatively high C/N ratio of the composting matrix (C/N=56) and NH3 volatilization explained the limited increases in NH4+-N content, whereas concentrations of conservative nutrient elements (e.g. P, K, Ca, Mg, Fe) increased in proportion to OM mineralization, enriching the compost as a nutrient source for horticultural use. Nitrogen concentrations also increased to a small extent, but were much more dynamic and losses, probably associated with N volatilization mechanisms, were difficult to actively control. The physicochemical characteristics of the stabilized end-product, such as pH, electrical conductivity and OM content, were improved with the addition of bark to Acacia biomass, and the final compost characteristics were suitable for use for soil improvement and also as horticultural substrate components.
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Sylla, Youssouf Boundou; Kuroda, Masao; Yamada, Masayuki; Matsumoto, Naoko
2006-10-01
Pilot-scale composting was carried out with cow manure to evaluate the performances of two passive aeration systems: a conventional passive aeration system equipped with horizontal pipes and an unusual passive aeration method based on air delivery by means of vertical pipes. The effects of both types of passive aeration apparatus were investigated in order to determine the degree of composting rate by continuously monitoring temperature, moisture content, organic matter, electrical conductivity, pH and C/N ratio in the piles. Temperatures in the range of thermophily (55-65 degrees C) were reached in all runs within 1-2 days then lasting for about 1 week, a span long enough for pathogen abatement. Results suggest that passive aeration carried out by vertical pipes is more effective for air delivery into compost piles than conventional passive aeration of air adduction with horizontal pipes. The variation in the number of vertical pipes was revealed to be an important parameter for the control of composting rate and temperature. Composting rates estimated from the heat balance equation were substantially in agreement with those computed through the conversion ratio of total organic matter decrement. The conversion ratios and composting rates obtained in this study using passive aeration with vertical pipes were well aligned with those found using forced air delivery systems.
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Yu, Hang; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Yunshu; Zheng, Zhen; Hao, Xiaodi
2015-10-01
Bioelectrochemically-assisted anaerobic composting process (AnCBE) with dewatered sludge as the anode fuel was constructed to accelerate composting of dewatered sludge, which could increase the quality of the compost and harvest electric energy in comparison with the traditional anaerobic composting (AnC). Results revealed that the AnCBE yielded a voltage of 0.60 ± 0.02 V, and total COD (TCOD) removal reached 19.8 ± 0.2% at the end of 35 d. The maximum power density was 5.6 W/m(3). At the end of composting, organic matter content (OM) reduction rate increased to 19.5 ± 0.2% in AnCBE and to 12.9 ± 0.1% in AnC. The fuzzy comprehensive assessment (FCA) result indicated that the membership degree of class I of AnCBE compost (0.64) was higher than that of AnC compost (0.44). It was demonstrated that electrogenesis in the AnCBE could improve the sludge stabilization degree, accelerate anaerobic composting process and enhance composting maturity with bioelectricity generation. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Chan, Yiu C; Sinha, Rajiv K; Weijin Wang
2011-05-01
This study investigated greenhouse gas (GHG) emissions from three different home waste treatment methods in Brisbane, Australia. Gas samples were taken monthly from 34 backyard composting bins from January to April 2009. Averaged over the study period, the aerobic composting bins released lower amounts of CH(4) (2.2 mg m(- 2) h(-1)) than the anaerobic digestion bins (9.5 mg m(-2) h(-1)) and the vermicomposting bins (4.8 mg m(-2) h( -1)). The vermicomposting bins had lower N(2)O emission rates (1.2 mg m(-2) h(- 1)) than the others (1.5-1.6 mg m(-2) h( -1)). Total GHG emissions including both N(2)O and CH(4) were 463, 504 and 694 mg CO(2)-e m(- 2) h(-1) for vermicomposting, aerobic composting and anaerobic digestion, respectively, with N(2)O contributing >80% in the total budget. The GHG emissions varied substantially with time and were regulated by temperature, moisture content and the waste properties, indicating the potential to mitigate GHG emission through proper management of the composting systems. In comparison with other mainstream municipal waste management options including centralized composting and anaerobic digestion facilities, landfilling and incineration, home composting has the potential to reduce GHG emissions through both lower on-site emissions and the minimal need for transportation and processing. On account of the lower cost, the present results suggest that home composting provides an effective and feasible supplementary waste management method to a centralized facility in particular for cities with lower population density such as the Australian cities.
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Sunflower hulls degradation by co-composting with different nitrogen sources.
Conghos, M M; Aguirre, M E; Santamaría, R M
2006-09-01
The decomposition of sunflower hull and its mixtures was examined under mesophilic (M) and thermophilic (T) temperatures during 100 days. Thermophilic conditions were used to define the composting process. Vetch, alfalfa and ammonium nitrate were used as nitrogen co-substrates, in 6 treatments: sunflower hulls alone (C), sunflower hulls plus ammonium nitrate (CN), sunflower hulls plus alfalfa (CA), sunflower hulls plus alfalfa and ammonium nitrate (CAV), sunflower hulls plus vetch (CV), sunflower hulls plus vetch and ammonium nitrate (CVN). Total organic carbon (TOC), oxidizable carbon (OC), dry matter, ashes content, total nitrogen (N), cellulose, hemicellulose, lignin, pH, electrical conductivity and C to N ratio were measured to asses the efficiency of the composting process and to determine the best amendment. Results show that sunflower hulls (Sh) treatment with the organic amendments had a better response than the inorganic ones. This was concluded from the variation in the fiberfractions, the decrease in dry matter and the major decrease in C to N ratio.
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NASA Astrophysics Data System (ADS)
Chen, Huixia; Dou, Junfeng; Xu, Hongbin
2017-12-01
Sewage sludge compost biomass was used as a novel biosorbent to remove hexavalent chromium from water. Surface area analysis, scanning electron microscopy, fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and point zero charge was applied to study the microstructure, compositions and chemical bonding states of the biomass adsorbent. Effects of contact time, biomass dosage, agitation speed, pH, the initial concentration of Cr(VI) and Cr(Ⅲ) on its adsorption removal were also performed in the batch experiments. A model describing adsorption, desorption and reduction phenomena during the sorption process has been referenced to model Cr(VI) sorption onto sewage sludge compost biomass. The result of characterization test shows that adsorption of Cr(VI) onto sewage sludge compost biomass followed by the partial reduction to Cr(Ⅲ) by biomass groups such as hydroxyl, carboxyl, and amino groups. The absorption kinetics model in the description of adsorption-coupled reduction of Cr(VI) fits successfully the kinetic data obtained at different temperatures and describes the kinetics profile of total, hexavalent and trivalent chromium. The study shows that sewage sludge compost biomass could be used as a potential biosorbent for removal of hexavalent chromium from wastewaters.
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Erickson, Marilyn C; Liao, Jean; Jiang, Xiuping; Doyle, Michael P
2014-11-01
Two separate studies were conducted to address the condition and the type of feedstocks used during composting of dairy manure. In each study, physical (temperature), chemical (ammonia, volatile acids, and pH), and biological (Salmonella, Listeria monocytogenes, and Escherichia coli O157:H7) parameters were monitored during composting in bioreactors to assess the degree to which they were affected by the experimental variables and, ultimately, the ability of the chemical and physical parameters to predict the fate of pathogens during composting. Compost mixtures that contained either aged dairy manure or pine needles had reduced heat generation; therefore, pathogen reduction took longer than if fresh manure or carbon amendments of wheat straw or peanut hulls were used. Based on regression models derived from these results, ammonia concentration, in addition to heat, were the primary factors affecting the degree of pathogen inactivation in compost mixtures formulated to an initial carbon-nitrogen (C:N) ratio of 40:1, whereas, the pH of the compost mixture along with the amount of heat exposure were most influential in compost mixtures formulated to an initial C:N ratio of 30:1. Further studies are needed to validate these models so that additional criteria in addition to time and temperature can be used to evaluate the microbiological safety of composted manures.
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Greenhouse gas emissions from home composting of organic household waste
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andersen, J.K., E-mail: jka@env.dtu.d; Boldrin, A.; Christensen, T.H.
2010-12-15
The emission of greenhouse gases (GHGs) is a potential environmental disadvantage of home composting. Because of a lack of reliable GHG emission data, a comprehensive experimental home composting system was set up. The system consisted of six composting units, and a static flux chamber method was used to measure and quantify the GHG emissions for one year composting of organic household waste (OHW). The average OHW input in the six composting units was 2.6-3.5 kg week{sup -1} and the temperature inside the composting units was in all cases only a few degrees (2-10 {sup o}C) higher than the ambient temperature.more » The emissions of methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) were quantified as 0.4-4.2 kg CH{sub 4} Mg{sup -1} input wet waste (ww) and 0.30-0.55 kg N{sub 2}O Mg{sup -1} ww, depending on the mixing frequency. This corresponds to emission factors (EFs) (including only CH{sub 4} and N{sub 2}O emissions) of 100-239 kg CO{sub 2}-eq. Mg{sup -1} ww. Composting units exposed to weekly mixing had the highest EFs, whereas the units with no mixing during the entire year had the lowest emissions. In addition to the higher emission from the frequently mixed units, there was also an instant release of CH{sub 4} during mixing which was estimated to 8-12% of the total CH{sub 4} emissions. Experiments with higher loads of OHW (up to 20 kg every fortnight) entailed a higher emission and significantly increased overall EFs (in kg substance per Mg{sup -1} ww). However, the temperature development did not change significantly. The GHG emissions (in kg CO{sub 2}-eq. Mg{sup -1} ww) from home composting of OHW were found to be in the same order of magnitude as for centralised composting plants.« less
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Greenhouse gas emissions from home composting of organic household waste.
Andersen, J K; Boldrin, A; Christensen, T H; Scheutz, C
2010-12-01
The emission of greenhouse gases (GHGs) is a potential environmental disadvantage of home composting. Because of a lack of reliable GHG emission data, a comprehensive experimental home composting system was set up. The system consisted of six composting units, and a static flux chamber method was used to measure and quantify the GHG emissions for one year composting of organic household waste (OHW). The average OHW input in the six composting units was 2.6-3.5 kg week(-1) and the temperature inside the composting units was in all cases only a few degrees (2-10 °C) higher than the ambient temperature. The emissions of methane (CH(4)) and nitrous oxide (N(2)O) were quantified as 0.4-4.2 kg CH(4)Mg(-1) input wet waste (ww) and 0.30-0.55 kg N(2)OMg(-1)ww, depending on the mixing frequency. This corresponds to emission factors (EFs) (including only CH(4) and N(2)O emissions) of 100-239 kg CO(2)-eq.Mg(-1)ww. Composting units exposed to weekly mixing had the highest EFs, whereas the units with no mixing during the entire year had the lowest emissions. In addition to the higher emission from the frequently mixed units, there was also an instant release of CH(4) during mixing which was estimated to 8-12% of the total CH(4) emissions. Experiments with higher loads of OHW (up to 20 kg every fortnight) entailed a higher emission and significantly increased overall EFs (in kg substance per Mg(-1)ww). However, the temperature development did not change significantly. The GHG emissions (in kg CO(2)-eq.Mg(-1)ww) from home composting of OHW were found to be in the same order of magnitude as for centralised composting plants. Copyright © 2010 Elsevier Ltd. All rights reserved.
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McLaughlin, M R; Brooks, J P; Adeli, A; Miles, D M
2015-11-01
Disposition of mortalities challenges confined animal feeding operations (CAFOs), especially sow (farrowing) farms, which experience mortalities daily. Regulations and transportation costs may preclude incineration, landfill burial, and rendering; therefore, swine CAFOs in Mississippi in the Mid-South U.S. often compost mortalities. In this study, a farm-standard composting mix of sawdust (S) and water (W) was compared with mixes where N was supplied by broiler litter (L) and water was replaced with swine lagoon effluent (E). The objective was to assess the effects of these manure byproducts: 1) on nutrients and bacteria in composts destined for land application; and 2) on emissions of ammonia and greenhouse gases. Three replications of four mixes (SW, SLW, SE, SLE) were compared in microcosms comprising modified plastic recycling bins. The experiment was repeated three times in different seasons in one year. Mixes were compared for differences in temperature, water content, nutrients (C, N, P, K, Ca, Mg, Na, Mn, Fe, Cu, Zn), bacteria (Gram-, Gram+, Clostridium perfringens, Salmonella, Listeria, Escherichia coli), and emissions (NH3, CO2, CH4, N2O). Litter addition increased composting temperatures initially and after aerations; increased nutrient concentrations, except C, in start mixes and all except C and N, in finish mixes; increased Gram+ bacteria, Salmonella, and E. coli in start mixes, but only Gram+s in finish mixes; and increased emissions. Effluent addition increased early composting temperatures; had no effect on nutrients or bacteria, except increased C. perfringens in start, but not finish mixes; and had no effect on emissions. Nutrients in finish composts did not differ among mixes for N (average 3.3%), but litter composts had more P and K, and lower N:P than composts without litter. Improving mortality composting is of global importance as increasing livestock populations and intensive animal production systems require practical, safe, environmentally sound disposal of carcasses. Published by Elsevier B.V.
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Vandecasteele, Bart; Sinicco, Tania; D'Hose, Tommy; Vanden Nest, Thijs; Mondini, Claudio
2016-03-01
We investigated the use of biochar (10% on a dry weight basis) to improve the composting process and/or the compost quality by adding it to either the feedstock mixture or the mature compost. The addition of biochar to the feedstocks was essayed in a full scale trial using a mixture of green waste and the organic fraction of municipal solid waste. Addition of biochar to mature compost was performed in a medium scale experiment. The use of biochar, even in small amounts, changed the composting process and the properties of the end products. However these effects depended on the time of application. We observed a faster decomposition in the bio-oxidative phase and lower greenhouse gas emissions when biochar was added at the beginning of the composting process, and a reduction in readily available P when biochar was applied during compost storage. Biochar as a means to increase the C content of the compost was only effective during compost storage. The P fertilizer replacement value of the compost with and without biochar was tested in a plant trial with annual ryegrass. While there was a clear effect on readily available P concentrations in the compost, adding biochar to the feedstock or the compost did not affect the P fertilizer replacement value. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria
NASA Astrophysics Data System (ADS)
Space Agriculture Task Force; Ishikawa, Y.; Tomita-Yokotani, K.; Hashimoto, H.; Kitaya, Y.; Yamashita, M.; Nagatomo, M.; Oshima, T.; Wada, H.
Manned Mars exploration, especially for extended periods of time, will require recycle of materials to support human life. Here, a conceptual design is developed for a Martian agricultural system driven by biologically regenerative functions. One of the core biotechnologies function is the use of hyper-thermophilic aerobic composting bacterial ecology. These thermophilic bacteria can play an important role in increasing the effectiveness of the processing of human metabolic waste and inedible biomass and of converting them to fertilizer for the cultivation of plants. This microbial technology has been already well established for the purpose of processing sewage and waste materials for small local communities in Japan. One of the characteristics of the technology is that the metabolic heat release that occurs during bacterial fermentation raises the processing temperature sufficiently high at 80 100 °C to support hyper-thermophilic bacteria. Such a hyper-thermophilic system is found to have great capability of decomposing wastes including even their normally recalcitrant components, in a reasonably short period of time and of providing a better quality of fertilizer as an end-product. High quality compost has been shown to be a key element in creating a healthy regenerative food production system. In ground-based studies, the soil microbial ecology after the addition of high quality compost was shown to improve plant growth and promote a healthy symbiosis of arbuscular mycorrhizal fungi. Another advantage of such high processing temperature is the ability to sterilize the pathogenic organisms through the fermentation process and thus to secure the hygienic safety of the system. Plant cultivation is one of the other major systems. It should fully utilize solar energy received on the Martian surface for supplying energy for photosynthesis. Subsurface water and atmospheric carbon dioxide mined on Mars should be also used in the plant cultivation system. Oxygen and food production for human thus rely on local Martian resources. A tree growing subsystem will also give an interesting feature to Martian agriculture. In addition to producing excess oxygen, trees’ rigid body will provide structural material, which can be used for habitat construction. The combination of hyper-thermophilic aerobic composting, plant cultivation, and tree growing with utilizing in-situ natural local resources available on Mars can provide important elements which can enable space agriculture on Mars.
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Grigatti, Marco; Cavani, Luciano; Ciavatta, Claudio
2007-01-01
Three blends formed by: agro-industrial waste, wastewater sewage sludge, and their mixture, blended with tree pruning as bulking agent, were composted over a 3-month period. During the composting process the blends were monitored for the main physical and chemical characteristics. Electrofocusing (EF) was carried out on the extracted organic matter. The EF profiles were analyzed by principal component analysis (PCA) in order to assess the suitability of EF to evaluate the stabilisation level during the composting process. Throughout the process, the blends showed a general shifting of focused bands, from low to high pH, even though the compost origin affected the EF profiles. If the EF profile is analyzed by dividing it into pH regions, the interpretation of the results can be affected by the origin of compost. A good clustering of compost samples depending on the process time was obtained by analyzing the whole profile by PCA. Analysis of EF results with PCA represents a useful analytical technique to study the evolution and the stabilisation of composted organic matter.
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NASA Astrophysics Data System (ADS)
Taha, M. P. M.; Drew, G. H.; Tamer Vestlund, A.; Aldred, D.; Longhurst, P. J.; Pollard, S. J. T.
Actinomycetes are the dominant bacteria isolated from bioaerosols sampled at composting facilities. Here, a novel method for the isolation of actinomycetes is reported, overcoming masking of conventional agar plates, as well as reducing analysis time and costs. Repeatable and reliable actinomycetes growth was best achieved using a soil compost media at an incubation temperature of 44 °C and 7 days' incubation. The results are of particular value to waste management operators and their advisors undertaking regulatory risk assessments that support environmental approvals for compost facilities.
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Environmental impact of mushroom compost production.
Leiva, Francisco; Saenz-Díez, Juan-Carlos; Martínez, Eduardo; Jiménez, Emilio; Blanco, Julio
2016-09-01
This research analyses the environmental impact of the creation of Agaricus bisporus compost packages. The composting process is the intermediate stage of the mushroom production process, subsequent to the mycelium cultivation stage and prior to the fruiting bodies cultivation stage. A full life cycle assessment model of the Agaricus bisporus composting process has been developed through the identification and analysis of the inputs-outputs and energy consumption of the activities involved in the production process. The study has been developed based on data collected from a plant during a 1 year campaign, thereby obtaining accurate information used to analyse the environmental impact of the process. A global analysis of the main stages of the process shows that the process that has the greatest impact in most categories is the compost batch preparation process. This is due to an increased consumption of energy resources by the machinery that mixes the raw materials to create the batch. At the composting process inside the tunnel stage, the activity that has the greatest impact in almost all categories studied is the initial stage of composting. This is due to higher energy consumption during the process compared to the other stages. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
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The effect of composting on the persistence of four ionophores in dairy manure and poultry litter
USDA-ARS?s Scientific Manuscript database
Manure composting is a well-described approach for stabilization of nutrients and reduction of pathogens and odors. Although composting studies have shown that thermophilic temperatures and aerobic conditions can increase removal rates of selected antibiotics, comparable information is lacking for ...
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Wastewater Biosolid Composting Optimization Based on UV-VNIR Spectroscopy Monitoring
Temporal-Lara, Beatriz; Melendez-Pastor, Ignacio; Gómez, Ignacio; Navarro-Pedreño, Jose
2016-01-01
Conventional wastewater treatment generates large amounts of organic matter–rich sludge that requires adequate treatment to avoid public health and environmental problems. The mixture of wastewater sludge and some bulking agents produces a biosolid to be composted at adequate composting facilities. The composting process is chemically and microbiologically complex and requires an adequate aeration of the biosolid (e.g., with a turner machine) for proper maturation of the compost. Adequate (near) real-time monitoring of the compost maturity process is highly difficult and the operation of composting facilities is not as automatized as other industrial processes. Spectroscopic analysis of compost samples has been successfully employed for compost maturity assessment but the preparation of the solid compost samples is difficult and time-consuming. This manuscript presents a methodology based on a combination of a less time-consuming compost sample preparation and ultraviolet, visible and short-wave near-infrared spectroscopy. Spectroscopic measurements were performed with liquid compost extract instead of solid compost samples. Partial least square (PLS) models were developed to quantify chemical fractions commonly employed for compost maturity assessment. Effective regression models were obtained for total organic matter (residual predictive deviation—RPD = 2.68), humification ratio (RPD = 2.23), total exchangeable carbon (RPD = 2.07) and total organic carbon (RPD = 1.66) with a modular and cost-effective visible and near infrared (VNIR) spectroradiometer. This combination of a less time-consuming compost sample preparation with a versatile sensor system provides an easy-to-implement, efficient and cost-effective protocol for compost maturity assessment and near-real-time monitoring. PMID:27854280
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Wastewater Biosolid Composting Optimization Based on UV-VNIR Spectroscopy Monitoring.
Temporal-Lara, Beatriz; Melendez-Pastor, Ignacio; Gómez, Ignacio; Navarro-Pedreño, Jose
2016-11-15
Conventional wastewater treatment generates large amounts of organic matter-rich sludge that requires adequate treatment to avoid public health and environmental problems. The mixture of wastewater sludge and some bulking agents produces a biosolid to be composted at adequate composting facilities. The composting process is chemically and microbiologically complex and requires an adequate aeration of the biosolid (e.g., with a turner machine) for proper maturation of the compost. Adequate (near) real-time monitoring of the compost maturity process is highly difficult and the operation of composting facilities is not as automatized as other industrial processes. Spectroscopic analysis of compost samples has been successfully employed for compost maturity assessment but the preparation of the solid compost samples is difficult and time-consuming. This manuscript presents a methodology based on a combination of a less time-consuming compost sample preparation and ultraviolet, visible and short-wave near-infrared spectroscopy. Spectroscopic measurements were performed with liquid compost extract instead of solid compost samples. Partial least square (PLS) models were developed to quantify chemical fractions commonly employed for compost maturity assessment. Effective regression models were obtained for total organic matter (residual predictive deviation-RPD = 2.68), humification ratio (RPD = 2.23), total exchangeable carbon (RPD = 2.07) and total organic carbon (RPD = 1.66) with a modular and cost-effective visible and near infrared (VNIR) spectroradiometer. This combination of a less time-consuming compost sample preparation with a versatile sensor system provides an easy-to-implement, efficient and cost-effective protocol for compost maturity assessment and near-real-time monitoring.
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Yahya, Azmi; Sye, Chong Puay; Ishola, Tajudeen Abiodun; Suryanto, Hadi
2010-11-01
Formation of compost from oil palm empty fruit bunches (EFB) and decanter cake slurry by adding palm oil mill effluent (POME) with regular turning operation was investigated. The experiment was conducted in a commercial composting plant under the normal production process. The addition of decanter cake slurry has hastened the composting process of the EFB. The C/N ratio after 51 days for the mature compost with the decanter cake slurry was 18.65 while that of the matured compost without the decanter cake slurry remained high at 28.96. The compost formed from the addition of decanter cake to EFB and POME had 46.4% nitrogen, 17.9% phosphorus, 17.7% potassium and 23.1% calcium more than that without decanter cake. The use of compost produced from EFB, POME and decanter cake slurry could solve more environmental problems and enhance economic benefits in the oil palm industry.
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Conditions for energy generation as an alternative approach to compost utilization.
Raclavska, H; Juchelkova, D; Skrobankova, H; Wiltowski, T; Campen, A
2011-01-01
Very strict limits constrain the current possibilities for compost utilization in agriculture and for land reclamation, thus creating a need for other compost utilization practices. A favourable alternative can be compost utilization as a renewable heat source - alternative fuel. The changes of the basic physical-chemical parameters during the composting process are evaluated. During the composting process, energy losses of 920 kJ/kg occur, caused by carbohydrate decomposition (loss of 12.64% TOC). The net calorific value for mature compost was 11.169 kJ/kg dry matter. The grain size of compost below 0.045 mm has the highest ash content. The energetic utilization of compost depended on moisture, which can be influenced by paper addition or by prolonging the time of maturation to six months.
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Bacterial diversity at different stages of the composting process
2010-01-01
Background Composting is an aerobic microbiological process that is facilitated by bacteria and fungi. Composting is also a method to produce fertilizer or soil conditioner. Tightened EU legislation now requires treatment of the continuously growing quantities of organic municipal waste before final disposal. However, some full-scale composting plants experience difficulties with the efficiency of biowaste degradation and with the emission of noxious odours. In this study we examine the bacterial species richness and community structure of an optimally working pilot-scale compost plant, as well as a full-scale composting plant experiencing typical problems. Bacterial species composition was determined by isolating total DNA followed by amplifying and sequencing the gene encoding the 16S ribosomal RNA. Results Over 1500 almost full-length 16S rRNA gene sequences were analysed and of these, over 500 were present only as singletons. Most of the sequences observed in either one or both of the composting processes studied here were similar to the bacterial species reported earlier in composts, including bacteria from the phyla Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria and Deinococcus-Thermus. In addition, a number of previously undetected bacterial phylotypes were observed. Statistical calculations estimated a total bacterial diversity of over 2000 different phylotypes in the studied composts. Conclusions Interestingly, locally enriched or evolved bacterial variants of familiar compost species were observed in both composts. A detailed comparison of the bacterial diversity revealed a large difference in composts at the species and strain level from the different composting plants. However, at the genus level, the difference was much smaller and illustrated a delay of the composting process in the full-scale, sub-optimally performing plants. PMID:20350306
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Zhou, Hai-Bin; Chen, Tong-Bin; Gao, Ding; Zheng, Guo-Di; Chen, Jun; Pan, Tian-Hao; Liu, Hong-Tao; Gu, Run-Yao
2014-11-01
Reducing moisture in sewage sludge is one of the main goals of sewage sludge composting and biodrying. A mathematical model was used to simulate the performance of water removal under different aeration strategies. Additionally, the correlations between temperature, moisture content (MC), volatile solids (VS), oxygen content (OC), and ambient air temperature and aeration strategies were predicted. The mathematical model was verified based on coefficients of correlation between the measured and predicted results of over 0.80 for OC, MC, and VS, and 0.72 for temperature. The results of the simulation showed that water reduction was enhanced when the average aeration rate (AR) increased to 15.37 m(3) min(-1) (6/34 min/min, AR: 102.46 m(3) min(-1)), above which no further increase was observed. Furthermore, more water was removed under a higher on/off time of 7/33 (min/min, AR: 87.34 m(3) min(-1)), and when ambient air temperature was higher. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Composting of Sewage Sludge Using Recycled Matured Compost as a Single Bulking Agent
NASA Astrophysics Data System (ADS)
Zhang, Xiangyang; Ren, Jian; Niu, Huasi; Wu, Xingwu
2010-11-01
Pretreatment (bulking agent choice and mixing) is an essential phase of dewatered raw sludge (RS) composting affecting its industrialization significantly. In this paper recycled compost (RC) was chosen as a single bulking agent in the composting experiment instead of other agents such as sawdust, rice straw, MSW, and the mixing machine was developed for mixing of SS and RC. According to the mixing experiment, SS and RC can be mixed uniformly and formed into small particles of 10˜15 mm in diameter, which improved the availability of oxygen during composting. The effect of different volumetric ratios of RS to RC, 1:1 (Exp.1), 1:2 (Exp.2) and 1:4 (Exp.3), on the performance of composting was investigated in detail. Temperature, oxygen consumption rate, organic matter, C/N ratio and moisture content were monitored in each experiment. In despite of low initial C/N of the mixture, intensive fermentation happened in all the experiments. Exp.1 and Exp.2 achieved stability and sanitization, but Exp 1 took more days to accomplish the fermentation. Exp 3 maintained thermophilic temperatures for a shortest time and did not satisfy the necessary sanitation requirements because more RC was recycled. In all experiments, the moisture content of their final composts were too high to be used as bulking agents before extra moisture was reduced. RS: RC = 1:2 (v/v) was the optimum and advisable proportion for the industrialization of sewage sludge composting of, the composting period was about 10 days, and the aeration rate 0.05 m3/(m3ṡmin) was appropriate in this study.
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Nitrogen losses and chemical parameters during co-composting of solid wastes and liquid pig manure.
Vázquez, M A; de la Varga, D; Plana, R; Soto, M
2017-07-04
The aim of this research was to study nitrogen losses during the treatment of the liquid fraction (LF) of pig manure by co-composting and to establish the best conditions for compost production with higher nitrogen and low heavy metal contents. Windrows were constituted with the solid fraction (SF) of pig manure, different organic waste (SF of pig manure, sawdust and grape bagasse) as co-substrate and Populus spp. wood chips as bulking material and watered intensely with the LF. Results show that nitrogen losses ranged from 30% to 66% of initial nitrogen and were mainly governed by substrate to bulking mass ratio and liquid fraction to substrate (LF/S) ratio, and only secondarily by operational parameters. Nitrogen losses decreased from 55-65% at low LF/S ratios (1.7-1.9 m 3 /t total solids (TS)) to 30-39% at high LF/S ratios (4.4-4.7 m 3 /t TS). Therefore, integrating the LF in the composting process at high LF/S ratios favoured nitrogen recovery and conservation. Nitrogen in the fine fraction (ranging from 27% to 48% of initial nitrogen) was governed by operational parameters, namely pH and temperature. Final compost showed low content in most heavy metals, but Zn was higher than the limits for compost use in agriculture. Zn content in the obtained compost varied from 1863 to 3269 mg/kg dm, depending on several factors. The options for obtaining better quality composts from the LF of pig manure are selecting co-substrates with low heavy metal content and using them instead of the SF of pig manure.
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Tanaka, Ryusuke; Miyamoto, Hirokuni; Inoue, Shin-Ichi; Shigeta, Kazuhiro; Kondo, Masakazu; Ito, Toshiyuki; Kodama, Hiroaki; Miyamoto, Hisashi; Matsushita, Teruo
2016-05-01
Recently, a compost fermented with marine animals with thermophilic Bacillaceae in a clean and exclusive process at high temperature was reported as a possible feed additive to improve the healthy balance in sea fish and mammals (i.e., pigs and rodents). Here, the effects of the oral administration of the compost on the muscle and internal organs of carp (Cyprinus carpio) as a freshwater fish model were investigated. The fatty acid composition was different in the muscle of the carp fed with or without the compost extract, but there was little difference in the hepatopancreas. The accumulation of triacylglycerols, cholesterol, lipid peroxide and hydroxyl lipids decreased in the muscle after the oral administration of the compost extract in the carps over 12 weeks, but the accumulation did not always decrease in the hepatopancreas. In contrast, free-radical-scavenging activities and the concentrations of free amino acids in the muscle did not always increase and was dependent on the dose of the compost at 12 weeks. The scavenging activities and part of free amino acid levels in the muscle of the carp were improved at 24 weeks after a high dose of compost exposure, and then the survival rates of the carp were maintained. Thus, the oral administration of thermophile-fermented compost can prevent peroxidation and increase the content of free amino acids in the muscle of the freshwater fish, depending on the dose and term of the administration, and may be associated with the viability of the fish. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
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Borges, Yan V; Alves, Luciano; Bianchi, Ivan; Espíndola, Jonas C; Oliveira, Juahil M De; Radetski, Claudemir M; Somensi, Cleder A
2017-11-02
The goal of this study was to optimize the mixture of swine manure (SM) and cattle manure (CM) used in the vermicomposting process, seeking to increase the manure biodegradation rate and enhance the biomass production of both earthworms and higher plants. To achieve this goal, physico-chemical parameters were determined to assess the final compost quality after 50 days of vermicomposting. The different manure ratios used to produce the composts (C) were as follows (SM:CM, % m/m basis): C1 100:0, C2 (75:25), C3 (50:50), C4 (25:75), and C5 (0:100). In addition, the earthworm biomass and the phytoproductivity of lettuce (Lactuca sativa L.) plants grown in mixtures (1:1) of natural soil and the most viable vermicomposts were investigated. The C1 and C2 compost compositions were associated with high earthworm mortality rates. The C3 compost provided the highest mineral concentrations and C5 showed the highest lettuce yield (wet biomass). The results verify that stabilized cattle manure is an excellent substrate for the vermicomposting process and that fresh swine manure must be mixed with pre-stabilized cattle manure to ensure an optimized vermicomposting process, which must be controlled in terms of temperature and ammonia levels. It is concluded that small livestock farmers could add value to swine manure by applying the vermicomposting process, without the need for high investments and with a minimal requirement for management of the biodegradation process. These are important technical aspects to be considered when circular economy principles are applied to small farms.
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Zhang, Zhenhua; Zhao, Juan; Yu, Cigang; Dong, Shanshan; Zhang, Dini; Yu, Ran; Wang, Changyong; Liu, Yan
2015-12-01
Improper treatment of penicillin fermentation fungi residue (PFFR), one of the by-products of penicillin production process, may result in environmental pollution due to the high concentration of penicillin. Aerobic co-composting of PFFR with pig manure was determined to degrade penicillin in PFFR. Results showed that co-composting of PFFR with pig manure can significantly reduce the concentration of penicillin in PFFR, make the PFFR-compost safer as organic fertilizer for soil application. More than 99% of penicillin in PFFR were removed after 7-day composting. PFFR did not affect the composting process and even promote the activity of the microorganisms in the compost. Quantitative PCR (qPCR) indicated that the bacteria and actinomycetes number in the AC samples were 40-80% higher than that in the pig-manure compost (CK) samples in the same composting phases. This research indicated that the aerobic co-composting was a feasible PFFR treatment method. Copyright © 2015 Elsevier Ltd. All rights reserved.
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de Guardia, A; Petiot, C; Benoist, J C; Druilhe, C
2012-06-01
The paper focused on the modelling of the heat transfers during composting in a pilot-scale reactor under forced aeration. The model took into account the heat production and the transfers by evaporation, convection between material and gas crossing the material, conduction and surface convection between gas and material in bottom and upper parts of the reactor. The model was adjusted thanks to the measurements practised during fifteen composting experiments in which five organic wastes were, each, composted under three constant aeration rates. Heat production was considered proportional to oxygen consumption rate and the enthalpy per mole oxygen consumed was assumed constant. The convective heat transfer coefficients were determined on basis of the continuous measurements of the temperatures of both the lid and the bottom part of the reactor. The model allowed a satisfying prediction of the temperature of the composting material. In most cases, the mean absolute discard between the experimental and the simulated temperatures was inferior to 2.5°C and the peaks of temperature occurred with less than 8h delay. For the half of the experiments the temperature discard between the simulated peak and the experimental one was inferior to 5°C. On basis of the calculation of a stoichiometric production of water through oxidation of the biodegradable organic matter, the simulation of water going out from material as vapour also allowed a rather satisfying prediction of the mass of water in final mixture. The influence of the aeration rate on every type of heat loss was characterized. Finally, the model was used to evaluate the impacts on material temperature caused by the change of the insulation thickness, the ambient temperature, take the lid away, the increase or the decrease of the mass of waste to compost. Copyright © 2012 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Guardia, A. de, E-mail: amaury.de-guardia@irstea.fr; Universite Europeenne de Bretagne, F-35000 Rennes; Petiot, C.
2012-06-15
The paper focused on the modelling of the heat transfers during composting in a pilot-scale reactor under forced aeration. The model took into account the heat production and the transfers by evaporation, convection between material and gas crossing the material, conduction and surface convection between gas and material in bottom and upper parts of the reactor. The model was adjusted thanks to the measurements practised during fifteen composting experiments in which five organic wastes were, each, composted under three constant aeration rates. Heat production was considered proportional to oxygen consumption rate and the enthalpy per mole oxygen consumed was assumedmore » constant. The convective heat transfer coefficients were determined on basis of the continuous measurements of the temperatures of both the lid and the bottom part of the reactor. The model allowed a satisfying prediction of the temperature of the composting material. In most cases, the mean absolute discard between the experimental and the simulated temperatures was inferior to 2.5 Degree-Sign C and the peaks of temperature occurred with less than 8 h delay. For the half of the experiments the temperature discard between the simulated peak and the experimental one was inferior to 5 Degree-Sign C. On basis of the calculation of a stoichiometric production of water through oxidation of the biodegradable organic matter, the simulation of water going out from material as vapour also allowed a rather satisfying prediction of the mass of water in final mixture. The influence of the aeration rate on every type of heat loss was characterized. Finally, the model was used to evaluate the impacts on material temperature caused by the change of the insulation thickness, the ambient temperature, take the lid away, the increase or the decrease of the mass of waste to compost.« less
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Neher, Deborah A.; Weicht, Thomas R.; Bates, Scott T.; Leff, Jonathan W.; Fierer, Noah
2013-01-01
Compost production is a critical component of organic waste handling, and compost applications to soil are increasingly important to crop production. However, we know surprisingly little about the microbial communities involved in the composting process and the factors shaping compost microbial dynamics. Here, we used high-throughput sequencing approaches to assess the diversity and composition of both bacterial and fungal communities in compost produced at a commercial-scale. Bacterial and fungal communities responded to both compost recipe and composting method. Specifically, bacterial communities in manure and hay recipes contained greater relative abundances of Firmicutes than hardwood recipes with hay recipes containing relatively more Actinobacteria and Gemmatimonadetes. In contrast, hardwood recipes contained a large relative abundance of Acidobacteria and Chloroflexi. Fungal communities of compost from a mixture of dairy manure and silage-based bedding were distinguished by a greater relative abundance of Pezizomycetes and Microascales. Hay recipes uniquely contained abundant Epicoccum, Thermomyces, Eurotium, Arthrobotrys, and Myriococcum. Hardwood recipes contained relatively abundant Sordariomycetes. Holding recipe constant, there were significantly different bacterial and fungal communities when the composting process was managed by windrow, aerated static pile, or vermicompost. Temporal dynamics of the composting process followed known patterns of degradative succession in herbivore manure. The initial community was dominated by Phycomycetes, followed by Ascomycota and finally Basidiomycota. Zygomycota were associated more with manure-silage and hay than hardwood composts. Most commercial composters focus on the thermophilic phase as an economic means to insure sanitation of compost from pathogens. However, the community succeeding the thermophilic phase begs further investigation to determine how the microbial dynamics observed here can be best managed to generate compost with the desired properties. PMID:24278144
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Neher, Deborah A; Weicht, Thomas R; Bates, Scott T; Leff, Jonathan W; Fierer, Noah
2013-01-01
Compost production is a critical component of organic waste handling, and compost applications to soil are increasingly important to crop production. However, we know surprisingly little about the microbial communities involved in the composting process and the factors shaping compost microbial dynamics. Here, we used high-throughput sequencing approaches to assess the diversity and composition of both bacterial and fungal communities in compost produced at a commercial-scale. Bacterial and fungal communities responded to both compost recipe and composting method. Specifically, bacterial communities in manure and hay recipes contained greater relative abundances of Firmicutes than hardwood recipes with hay recipes containing relatively more Actinobacteria and Gemmatimonadetes. In contrast, hardwood recipes contained a large relative abundance of Acidobacteria and Chloroflexi. Fungal communities of compost from a mixture of dairy manure and silage-based bedding were distinguished by a greater relative abundance of Pezizomycetes and Microascales. Hay recipes uniquely contained abundant Epicoccum, Thermomyces, Eurotium, Arthrobotrys, and Myriococcum. Hardwood recipes contained relatively abundant Sordariomycetes. Holding recipe constant, there were significantly different bacterial and fungal communities when the composting process was managed by windrow, aerated static pile, or vermicompost. Temporal dynamics of the composting process followed known patterns of degradative succession in herbivore manure. The initial community was dominated by Phycomycetes, followed by Ascomycota and finally Basidiomycota. Zygomycota were associated more with manure-silage and hay than hardwood composts. Most commercial composters focus on the thermophilic phase as an economic means to insure sanitation of compost from pathogens. However, the community succeeding the thermophilic phase begs further investigation to determine how the microbial dynamics observed here can be best managed to generate compost with the desired properties.
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Wang, Yongjiang; Niu, Wenjuan; Ai, Ping
2016-12-01
Dynamic estimation of heat transfer through composting reactor wall was crucial for insulating design and maintaining a sanitary temperature. A model, incorporating conductive, convective and radiative heat transfer mechanisms, was developed in this paper to provide thermal resistance calculations for composting reactor wall. The mechanism of thermal transfer from compost to inner surface of structural layer, as a first step of heat loss, was important for improving insulation performance, which was divided into conduction and convection and discussed specifically in this study. It was found decreasing conductive resistance was responsible for the drop of insulation between compost and reactor wall. Increasing compost porosity or manufacturing a curved surface, decreasing the contact area of compost and the reactor wall, might improve the insulation performance. Upon modeling of heat transfers from compost to ambient environment, the study yielded a condensed and simplified model that could be used to conduct thermal resistance analysis for composting reactor. With theoretical derivations and a case application, the model was applicable for both dynamic estimation and typical composting scenario. Copyright © 2016 Elsevier Ltd. All rights reserved.
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A systematic review on the composting of green waste: Feedstock quality and optimization strategies.
Reyes-Torres, M; Oviedo-Ocaña, E R; Dominguez, I; Komilis, D; Sánchez, A
2018-04-27
Green waste (GW) is an important fraction of municipal solid waste (MSW). The composting of lignocellulosic GW is challenging due to its low decomposition rate. Recently, an increasing number of studies that include strategies to optimize GW composting appeared in the literature. This literature review focuses on the physicochemical quality of GW and on the effect of strategies used to improve the process and product quality. A systematic search was carried out, using keywords, and 447 papers published between 2002 and 2018 were identified. After a screening process, 41 papers addressing feedstock quality and 32 papers on optimization strategies were selected to be reviewed and analyzed in detail. The GW composition is highly variable due to the diversity of the source materials, the type of vegetation, and climatic conditions. This variability limits a strict categorization of the GW physicochemical characteristics. However, this research established that the predominant features of GW are a C/N ratio higher than 25, a deficit in important nutrients, namely nitrogen (0.5-1.5% db), phosphorous (0.1-0.2% db) and potassium (0.4-0.8% db) and a high content of recalcitrant organic compounds (e.g. lignin). The promising strategies to improve composting of GW were: i) GW particle size reduction (e.g. shredding and separation of GW fractions); ii) addition of energy amendments (e.g. non-refined sugar, phosphate rock, food waste, volatile ashes), bulking materials (e.g. biocarbon, wood chips), or microbial inoculum (e.g. fungal consortia); and iii) variations in operating parameters (aeration, temperature, and two-phase composting). These alternatives have successfully led to the reduction of process length and have managed to transform recalcitrant substances to a high-quality end-product. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Shepherd, Marion W.; Kim, Jinkyung; Jiang, Xiuping; Doyle, Michael P.; Erickson, Marilyn C.
2011-01-01
Throughout four field trials, compost heaps covered with finished compost maintained temperatures under the physical covering that were ca. 7 to 15.5°C higher, resulting in rapid Escherichia coli O157:H7 reduction, than those of the heaps covered with fresh straw or left uncovered. Our results validated recommendations made by the U.S. Environmental Protection Agency for covering fresh compost. PMID:21622780
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Jeong, Seung Tak; Kim, Gil Won; Hwang, Hyun Young; Kim, Pil Joo; Kim, Sang Yoon
2018-02-01
Livestock manure application can stimulate greenhouse gas (GHG) emissions, especially methane (CH 4 ) in rice paddy. The stabilized organic matter (OM) is recommended to suppress CH 4 emission without counting the additional GHG emission during the composting process. To evaluate the effect of compost utilization on the net global warming potential (GWP) of a rice cropping system, the fluxes of GHGs from composting to land application were calculated by a life cycle assessment (LCA) method. The model framework was composed of GHG fluxes from industrial activities and biogenic GHG fluxes from the composting and rice cultivation processes. Fresh manure emitted 30MgCO 2 -eq.ha -1 , 90% and 10% of which were contributed by CH 4 and nitrous oxide (N 2 O) fluxes, respectively, during rice cultivation. Compost utilization decreased net GWP by 25% over that of the fresh manure during the whole process. The composting process increased the GWP of the industrial processes by 35%, but the 60% reduction in CH 4 emissions from the rice paddy mainly influenced the reduction of GWP during the overall process. Therefore, compost application could be a good management strategy to reduce GHG emissions from rice paddy systems. Copyright © 2017 Elsevier B.V. All rights reserved.
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Zhu, Fengxiang; Pan, Zaifa; Hong, Chunlai; Wang, Weiping; Chen, Xiaoyang; Xue, Zhiyong; Yao, Yanlai
2016-12-01
Changes in volatile organic compound contents in compost samples during pig manure composting were studied using a headspace, solid-phase micro-extraction method (HS-SPME) followed by gas chromatography with mass spectrometric detection (GC/MS). Parameters affecting the SPME procedure were optimized as follows: the coating was carbon molecular sieve/polydimethylsiloxane (CAR/PDMS) fiber, the temperature was 60°C and the time was 30min. Under these conditions, 87 compounds were identified from 17 composting samples. Most of the volatile components could only be detected before day 22. However, benzenes, alkanes and alkenes increased and eventually stabilized after day 22. Phenol and acid substances, which are important factors for compost quality, were almost undetectable on day 39 in natural compost (NC) samples and on day 13 in maggot-treated compost (MC) samples. Our results indicate that the approach can be effectively used to determine the composting times by analysis of volatile substances in compost samples. An appropriate composting time not only ensures the quality of compost and reduces the loss of composting material but also reduces the generation of hazardous substances. The appropriate composting times for MC and NC were approximately 22days and 40days, respectively, during the summer in Zhejiang. Copyright © 2016 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Azura Zakarya, Irnis; Azri Jamial, Khairul; Mat Tanda, Norazlinda
2018-03-01
Currently, the Ministry of Housing and Local Government manage solid waste in Malaysia, with the participation of the private sector. Food waste represents almost 60% of the total municipal solid waste disposed in the landfill. Material valorisation of food waste usually conducted by biological processes such as composting. Compost, an organic amendment, is the final product of the composting process. These processes are efficient, low cost and environmentally friendly alternative for managing food waste and are used extensively worldwide. Therefore, organic solid waste management practices program for the communities in Perlis was conducted. The main objective of this program was to instilling environment awareness especially among Perlis citizens. This study was investigated the impact of food waste or kitchen waste composting to the citizens in Perlis State and the beneficial of compost fertilizer to our environment especially in plant growth. Composting method was taught to the food premises owner, individuals, teachers, and students and their responses to the composting practices were then summarized. In future, we can prolong our landfill lifespan by practicing organic waste composting and can preserving our environment.
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Effect of light Sphagnum peat on odour formation in the early stages of biowaste composting.
Kurola, Jukka M; Arnold, Mona; Kontro, Merja H; Talves, Matti; Romantschuk, Martin
2010-05-01
In the present study, we investigated the effects of two bulking materials, Sphagnum peat and pine wood chips, on the early stages of biowaste composting in two pilot-scale processes. Emphasis was placed on studying the formation conditions of malodorous compost gases in the initial phases of the processes. The results showed that gas emission leaving an open windrow and a closed drum composting system contained elevated concentrations of fermentative microbial metabolites when acid Sphagnum peat (pH 3.2) was used as a bulking material. Moreover, the gas emission of the peat amended drum composter contained a high concentration of odour (up to 450,000oum(-3) of air). The highest odour values in the outlet gas of peat amended composts coincided with the elevated concentrations of volatile organic compounds such as acetoin and buthanedion. We conclude that the acidifying qualities of composting substrates or bulking material may intensify odour emission from biowaste composts and prolong the early stages of the composting process. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
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Cayuela, Maria Luz; Sánchez-Monedero, Miguel A; Roig, Asunción
2010-06-01
Two-phase olive mill waste (TPOMW) is a semisolid sludge generated by the olive oil industry. Its recycling as a soil amendment, either unprocessed or composted, is being promoted as a beneficial agricultural practice in the Mediterranean area. One of the major difficulties when composting TPOMW is the compaction of the material due to its dough-like texture, which leads to an inadequate aeration. For this reason, the addition of bulking agents is particularly important to attain a proper composting process. In this study we followed the evolution of two composting mixtures (A and B) prepared by mixing equal amounts of TPOMW and sheep litter (SL) (in a dry weight basis). In pile B grape stalks (GS) were added (10% dry weight) as bulking agent to study their effect on the development of the composting process and the final compost quality. The incorporation of grape stalks to the composting mixture changed the organic matter (OM) degradation dynamics and notably reduced the total amount of lixiviates. The evolution of several maturation indices (C/N, germination index, water soluble carbon, humification indices, C/N in the leachates) showed a faster and improved composting process when GS were added. Moreover, chemical (NH4+, NO3(-), cation exchange capacity, macro and micronutrients, heavy metals) and physical properties (bulk and real densities, air content, total water holding capacity, porosity) of the final composts were analysed and confirmed the superior quality of the compost where GS were added.
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[Interaction Between Sulfonamide Antibiotics Fates and Chicken Manure Composting].
Lin, Hui; Wang, Jian-mei; Sun, Wan-chun; Fu, Jian-rong; Chen, Hong-jin; Ma, Jun-wei
2016-05-15
Based on aerobic manure composting with or without the addition of a mixture of sulfadimethoxine SM2 and sulfamonomethoxine SMM (1:1, m/m), changes in the physic-chemical properties of manure compost, the microbial community physiological profiles, the antibiotics concentration and the abundances of five antibiotic resistance genes (ARGs) during the composting were tracked. The results indicated that the introduction of sulfonamide antibiotics led to inhibition on the basal respiration of manure compost during the early composting period, delayed the formation of thermophilic temperature and reduced the conversion of nutrients such as organic matter, ammonia nitrogen and nitrate nitrogen. Meanwhile, the introduction of sulfonamide antibiotics dramatically affected the physiological profile of microbial community in manure in the middle stage of composting. HPLC-MS/MS results showed that both SMM and SM2 in manure were completely degraded within 14 days, while the degradation rate of SMM was faster than that of SM2. For both composting treatments with or without addition of exogenous antibiotics, the relative abundance of sull and sul2 showed an initial decline in the first 14 or 21 days and a slight increase thereafter. The addition of exogenous antibiotics showed insignificant enhancement on increasing the relative abundance of sul1 and IntI1 in manure, but resulted in an apparent increase in sul2 relative abundance. Although the fates of tetQ and tetW during composting were different from that of sulfonamide ARGs, the introduction of sulfonamide antibiotics into manure increased the relative abundance of tetracycline ARGs. Redundancy analysis indicated that composting temperature correlated negatively with sul1, sul2 and IntI1 relative abundance in manure but had no obvious relationship with tetQ and tetW relative abundance. All the ARGs detected in this work correlated negatively with C/N ratio and the nitrate nitrogen concentration of manure compost but positively correlated with pH, moisture and ammonia nitrogen concentration of manure compost.
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9 CFR 82.7 - Interstate movement of manure and litter from a quarantined area.
Code of Federal Regulations, 2012 CFR
2012-01-01
... manure and litter at the destination listed on the permit. (b) Compost derived from manure generated by... composting site at the same time; (5) Following the composting process, the composted manure or litter... composted manure or litter from the infected site is removed at the same time; (7) The resulting compost...
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9 CFR 82.7 - Interstate movement of manure and litter from a quarantined area.
Code of Federal Regulations, 2013 CFR
2013-01-01
... manure and litter at the destination listed on the permit. (b) Compost derived from manure generated by... composting site at the same time; (5) Following the composting process, the composted manure or litter... composted manure or litter from the infected site is removed at the same time; (7) The resulting compost...
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Rotary drum composting of vegetable waste and tree leaves.
Kalamdhad, Ajay S; Singh, Yatish K; Ali, Muntjeer; Khwairakpam, Meena; Kazmi, A A
2009-12-01
High rate composting studies on institutional waste, i.e. vegetable wastes, tree leaves, etc., were conducted on a demonstration-scale (3.5 m(3)) rotary drum composter by evaluating changes in some physico-chemical and biological parameters. During composting, higher temperature (60-70 degrees C) at inlet zone and (50-60 degrees C) at middle zone were achieved which resulted in high degradation in the drum. As a result, all parameters including TOC, C/N ratio, CO(2) evolution and coliforms were decreased significantly within few days of composting. Within a week period, quality compost with total nitrogen (2.6%) and final total phosphorus (6 g/kg) was achieved; but relatively higher final values of fecal coliforms and CO(2) evolution, suggested further maturation. Thus, two conventional composting methods namely windrow (M1) and vermicomposting (M2) tried for maturation of primary stabilized compost. By examining these methods, it was suggested that M2 was found suitable in delivering fine grained, better quality matured compost within 20 days of maturation period.
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Effects of bean dregs and crab shell powder additives on the composting of green waste.
Zhang, Lu; Sun, Xiangyang
2018-07-01
Composting is an effective and economic technology for the recycling of organic waste. In this study, bean dregs (BD) (at 0, 35, and 45%) and crab shell powder (CSP) (at 0, 15, and 25%) were evaluated as additives during the two-stage composting of green waste (GW). The GW used in this experiment mainly consisted of branch cuttings collected during the maintenance of the urban green landscape. Combined additions of BD and CSP improved composting conditions and compost quality in terms of composting temperature, specific surface area, average pore diameter, pH and EC values, carbon dioxide release, ammonia and nitrous oxide emissions, E 4 /E 6 ratio, elemental composition and atomic ratios, organic matter degradation, microbial numbers, enzyme activities, compost phytotoxicity, and environmental and economic benefits. The combined addition of 35% BD and 25% CSP to the two-stage composting of GW resulted in the highest quality compost product in only 22 days. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Potential of a gypsum-free composting process of wheat straw for mushroom production.
Mouthier, Thibaut M B; Kilic, Baris; Vervoort, Pieter; Gruppen, Harry; Kabel, Mirjam A
2017-01-01
Wheat straw based composting generates a selective substrate for mushroom production. The first phase of this process requires 5 days, and a reduction in time is wished. Here, we aim at understanding the effect of gypsum on the duration of the first phase and the mechanism behind it. Hereto, the regular process with gypsum addition and the same process without gypsum were studied during a 5-day period. The compost quality was evaluated based on compost lignin composition analysed by py-GC/MS and its degradability by a commercial (hemi-)cellulolytic enzyme cocktail. The composting phase lead to the decrease of the pyrolysis products 4-vinylphenol and 4-vinylguaiacol that can be associated with p-coumarates and ferulates linking xylan and lignin. In the regular compost, the enzymatic conversion reached 32 and 39% for cellulose, and 23 and 32% for xylan after 3 and 5 days, respectively. In absence of gypsum similar values were reached after 2 and 4 days, respectively. Thus, our data show that in absence of gypsum the desired compost quality was reached 20% earlier compared to the control process.
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Potential of a gypsum-free composting process of wheat straw for mushroom production
Mouthier, Thibaut M. B.; Kilic, Baris; Vervoort, Pieter; Gruppen, Harry
2017-01-01
Wheat straw based composting generates a selective substrate for mushroom production. The first phase of this process requires 5 days, and a reduction in time is wished. Here, we aim at understanding the effect of gypsum on the duration of the first phase and the mechanism behind it. Hereto, the regular process with gypsum addition and the same process without gypsum were studied during a 5-day period. The compost quality was evaluated based on compost lignin composition analysed by py-GC/MS and its degradability by a commercial (hemi-)cellulolytic enzyme cocktail. The composting phase lead to the decrease of the pyrolysis products 4-vinylphenol and 4-vinylguaiacol that can be associated with p-coumarates and ferulates linking xylan and lignin. In the regular compost, the enzymatic conversion reached 32 and 39% for cellulose, and 23 and 32% for xylan after 3 and 5 days, respectively. In absence of gypsum similar values were reached after 2 and 4 days, respectively. Thus, our data show that in absence of gypsum the desired compost quality was reached 20% earlier compared to the control process. PMID:28982119
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Cáceres, Rafaela; Coromina, Narcís; Malińska, Krystyna; Martínez-Farré, F Xavier; López, Marga; Soliva, Montserrat; Marfà, Oriol
2016-12-01
Next generation of waste management systems should apply product-oriented bioconversion processes that produce composts or biofertilisers of desired quality that can be sold in high priced markets such as horticulture. Natural acidification linked to nitrification can be promoted during composting. If nitrification is enhanced, suitable compost in terms of pH can be obtained for use in horticultural substrates. Green waste compost (GW) represents a potential suitable product for use in growing medium mixtures. However its low N provides very limited slow-release nitrogen fertilization for suitable plant growth; and GW should be composted with a complementary N-rich raw material such as the solid fraction of cattle slurry (SFCS). Therefore, it is important to determine how very different or extreme proportions of the two materials in the mixture can limit or otherwise affect the nitrification process. The objectives of this work were two-fold: (a) To assess the changes in chemical and physicochemical parameters during the prolonged composting of extreme mixtures of green waste (GW) and separated cattle slurry (SFCS) and the feasibility of using the composts as growing media. (b) To check for nitrification during composting in two different extreme mixtures of GW and SFCS and to describe the conditions under which this process can be maintained and its consequences. The physical and physicochemical properties of both composts obtained indicated that they were appropriate for use as ingredients in horticultural substrates. The nitrification process occurred in both mixtures in the medium-late thermophilic stage of the composting process. In particular, its feasibility has been demonstrated in the mixtures with a low N content. Nitrification led to the inversion of each mixture's initial pH. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Co-composting of Beef Cattle Feedlot Manure with Construction and Demolition Waste.
Hao, Xiying; Hill, Brett; Caffyn, Pam; Travis, Greg; Olson, Andrew F; Larney, Francis J; McAllister, Tim; Alexander, Trevor
2014-09-01
With increased availability of dried distillers' grains with solubles (DDGS) as cattle feed and the need to recycle organic wastes, this research investigated the feasibility of co-composting DDGS cattle feedlot manure with construction and demolition (C&D) waste. Manure was collected from cattle fed a typical western Canadian finishing diet (CK) of 860 g rolled barley ( L.) grain, 100 g barley silage, and 40 g vitamin and mineral supplement kg dry matter (DM) and from cattle fed the same diet but (DG manure) with 300 g kg DM barley grain being replaced by DDGS. The CK and DG manures were co-composted with and without C&D waste in 13 m bins. Compost materials were turned on Days 14, 37, and 64, and terminated on Day 99. Adding C&D waste led to higher compost temperatures (0.4 to 16.3°C, average 7.2°C) than manure alone. Final composts had similar total C, total N, C/N ratios, and water-extractable K, Mg, and NO content across all treatments. However, adding C&D waste increased δC, δN, water-extractable SO, and Ca contents and decreased pH, total P (TP), water-extractable C, N, and P and most volatile fatty acids (VFA). The higher C&D compost temperatures should reduce pathogens while reduced VFA content should reduce odors. When using the final compost product, the increased SO and reduced TP and available N and P content in C&D waste compost should be taken into consideration. Increased S content in C&D compost may be beneficial for some crops grown on S-deficient soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
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Vandecasteele, Bart; Boogaerts, Christophe; Vandaele, Elke
2016-12-01
The question was tackled on how the green waste compost industry can optimally apply the available biomass resources for producing both bioenergy by combustion of the woody fraction, and high quality soil improvers as renewable sources of carbon and nutrients. Compost trials with removal of woody biomass before or after composting were run at 9 compost facilities during 3 seasons to include seasonal variability of feedstock. The project focused on the changes in feedstock and the effect on the end product characteristics (both compost and recovered woody biomass) of this woody biomass removal. The season of collection during the year clearly affected the biochemical and chemical characteristics of feedstock, woody biomass and compost. On one hand the effect of removal of the woody fraction before composting did not significantly affect compost quality when compared to the scenario where the woody biomass was sieved from the compost at the end of the composting process. On the other hand, quality of the woody biomass was not strongly affected by extraction before or after composting. The holocellulose:lignin ratio was used in this study as an indicator for (a) the decomposition potential of the feedstock mixture and (b) to assess the stability of the composts at the end of the process. Higher microbial activity in green waste composts (indicated by higher oxygen consumption) and thus a lower compost stability resulted in higher N immobilization in the compost. Removal of woody biomass from the green waste before composting did not negatively affect the compost quality when more intensive composting was applied. The effect of removal of the woody fraction on the characteristics of the green waste feedstock and the extracted woody biomass is depending on the season of collection. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Effective pine bark composting with the Dome Aeration Technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trois, Cristina; Polster, Andreas
2007-07-01
In South Africa garden refuse is primarily disposed of in domestic landfills. Due to the large quantities generated, any form of treatment would be beneficial for volume reduction, waste stabilization and resource recovery. Dome Aeration Technology (DAT) is an advanced process for aerobic biological degradation of garden refuse and general waste [Paar, S., Brummack, J., Gemende, B., 1999a. Advantages of dome aeration in mechanical-biological waste treatment. In: Proceedings of the 7th International Waste Management and Landfill Symposium, Cagliari, 4-8 October 1999; Paar, S., Brummack, J., Gemende, B., 1999b. Mechanical-biological waste stabilization by the dome aeration method. Environment Protection Engineering 25more » (3/99). Mollekopf, N., Brummack, J., Paar, S., Vorster, K., 2002. Use of the Dome Aeration Technology for biochemical stabilization of waste prior to landfilling. In: Proceedings of the Wastecon 2002, Waste Congress and Exhibition, Durban, South Africa.]. It is a non-reactor open windrow composting process, with the main advantage being that the input material needs no periodic turning. A rotting time of only 3-4 months indicates the high efficiency. Additionally, the low capital/operational costs, low energy inputs and limited plant requirements provide potential for use in aerobic refuse stabilization. The innovation in the DAT process is the passive aeration achieved by thermally driven advection through open windrows caused by temperature differences between the degrading material and the outside environment. This paper investigates the application of Dome Aeration Technology to pine bark composting as part of an integrated waste management strategy. A full-scale field experiment was performed at the Bisasar Road Landfill Site in Durban to assess the influence of climate, waste composition and operational conditions on the process. A test windrow was constructed and measurements of temperature and airflow through the material were taken. The process monitoring revealed that prevailing climatic conditions in a subtropical location do not affect the high efficiency of this technology. However, the composition of the input material can be detrimental for production of high quality compost because of a lack of nitrate.« less
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[Fungal community structure in phase II composting of Volvariella volvacea].
Chen, Changqing; Li, Tong; Jiang, Yun; Li, Yu
2014-12-04
To understand the fungal community succession during the phase II of Volvariella volvacea compost and clarify the predominant fungi in different fermentation stages, to monitor the dynamic compost at the molecular level accurately and quickly, and reveal the mechanism. The 18S rDNA-denaturing gradient gel electrophoresis (DGGE) and sequencing methods were used to analyze the fungal community structure during the course of compost. The DGGE profile shows that there were differences in the diversity of fungal community with the fermentation progress. The diversity was higher in the stages of high temperature. And the dynamic changes of predominant community and relative intensity was observed. Among the 20 predominant clone strains, 9 were unknown eukaryote and fungi, the others were Eurotiales, Aspergillus sp., Melanocarpus albomyces, Colletotrichum sp., Rhizomucor sp., Verticillium sp., Penicillium commune, Microascus trigonosporus and Trichosporon lactis. The 14 clone strains were detected in the stages of high and durative temperature. The fungal community structure and predominant community have taken dynamic succession during the phase II of Volvariella volvacea compost.
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Sun, Jiajun; Qian, Xun; Gu, Jie; Wang, Xiaojuan; Gao, Hua
2016-09-01
The effects of oxytetracycline (OTC) on nitrogen-fixing bacterial communities were investigated during cattle manure composting. The abundance and community structure of nitrogen-fixing bacteria were determined by qPCR and denaturing gradient gel electrophoresis (DGGE), respectively. The matrix was spiked with OTC at four levels: no OTC, 10mg/kg dry weight (DW) OTC (L), 60mg/kg DW OTC (M), and 200mg/kg DW OTC (H). The high temperature period of composting was shorter with M and H, and the decline in temperature during the cooling stage was accelerated by OTC. OTC had a concentration-dependent inhibitory effect on the nitrogenase activity during early composting, and the nifH gene abundance declined significantly during the later composting stage. The DGGE profile and statistical analysis showed that OTC changed the nitrogen-fixing bacterial community succession and reduced the community richness and dominance. The nitrogen-fixing bacterial community structure was affected greatly by the high level of OTC. Copyright © 2016. Published by Elsevier Ltd.
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Koolivand, Ali; Naddafi, Kazem; Nabizadeh, Ramin; Saeedi, Reza
2017-07-31
In this research, removal of petroleum hydrocarbons from oily sludge of crude oil storage tanks was investigated under the optimized conditions of in-vessel composting process and chemical oxidation with H 2 O 2 and Fenton. After determining the optimum conditions, the sludge was pre-treated with the optimum state of the oxidation process. Then, the determined optimum ratios of the sludge to immature compost were composted at a C:N:P ratio of 100:5:1 and moisture content of 55% for a period of 10 weeks. Finally, both pre-treated and composted mixtures were again oxidized with the optimum conditions of the oxidants. Results showed that total petroleum hydrocarbons (TPH) removal of the 1:8 and 1:10 composting reactors which were pre-treated with H 2 O 2 were 88.34% and 90.4%, respectively. In addition, reduction of TPH in 1:8 and 1:10 composting reactors which were pre-treated with Fenton were 83.90% and 84.40%, respectively. Without applying the pre-treatment step, the composting reactors had a removal rate of about 80%. Therefore, pre-treatment of the reactors increased the TPH removal. However, post-oxidation of both pre-treated and composted mixtures reduced only 13-16% of TPH. Based on the results, remarkable overall removal of TPH (about 99%) was achieved by using chemical oxidation and subsequent composting process. The study showed that chemical oxidation with H 2 O 2 followed by in-vessel composting is a viable choice for the remediation of the sludge.
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7 CFR 3201.64 - Compost activators and accelerators.
Code of Federal Regulations, 2014 CFR
2014-01-01
... PROCUREMENT Designated Items § 3201.64 Compost activators and accelerators. (a) Definition. Products in liquid or powder form designed to be applied to compost piles to aid in speeding up the composting process... 7 Agriculture 15 2014-01-01 2014-01-01 false Compost activators and accelerators. 3201.64 Section...
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7 CFR 3201.64 - Compost activators and accelerators.
Code of Federal Regulations, 2013 CFR
2013-01-01
... PROCUREMENT Designated Items § 3201.64 Compost activators and accelerators. (a) Definition. Products in liquid or powder form designed to be applied to compost piles to aid in speeding up the composting process... 7 Agriculture 15 2013-01-01 2013-01-01 false Compost activators and accelerators. 3201.64 Section...
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7 CFR 3201.64 - Compost activators and accelerators.
Code of Federal Regulations, 2012 CFR
2012-01-01
... PROCUREMENT Designated Items § 3201.64 Compost activators and accelerators. (a) Definition. Products in liquid or powder form designed to be applied to compost piles to aid in speeding up the composting process... 7 Agriculture 15 2012-01-01 2012-01-01 false Compost activators and accelerators. 3201.64 Section...
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Physical analyses of compost from composting plants in Brazil.
Barreira, L P; Philippi Junior, A; Rodrigues, M S; Tenório, J A S
2008-01-01
Nowadays the composting process has shown itself to be an alternative in the treatment of municipal solid wastes by composting plants. However, although more than 50% of the waste generated by the Brazilian population is composed of matter susceptible to organic composting, this process is, still today, insufficiently developed in Brazil, due to low compost quality and lack of investments in the sector. The objective of this work was to use physical analyses to evaluate the quality of the compost produced at 14 operative composting plants in the Sao Paulo State in Brazil. For this purpose, size distribution and total inert content tests were done. The results were analyzed by grouping the plants according to their productive processes: plants with a rotating drum, plants with shredders or mills, and plants without treatment after the sorting conveyor belt. Compost quality was analyzed considering the limits imposed by the Brazilian Legislation and the European standards for inert contents. The size distribution tests showed the influence of the machinery after the sorting conveyer on the granule sizes as well as the inert content, which contributes to the presence of materials that reduce the quality of the final product.
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Sossou, S K; Hijikata, N; Sou, M; Tezuka, R; Maiga, A H; Funamizu, N
2014-01-01
This study aimed to compare the inactivation rate and the mechanisms of pathogenic bacteria in three matrixes (sawdust, rice husk and charcoal) during the composting process. The inactivation rate was evaluated with Escherichia coli strain and the damaged parts and/or functions were evaluated with three different media. Normalized inactivation rate constant in three media and from three matrixes had no significant difference in each process (pure, 1 month and 2 months). The value in rice husk was relatively increased during 2 months but there was no significant difference. The inactivation rate constants of Tryptic Soy Agar (TSA) and Compact Dry E. coli/Coliform in pure sawdust and rice husk were relatively lower than that of Desoxycholate Agar, but increased in 2 months. This indicated that damaging part was changed from outer membrane to enzymes and metabolisms during the 2-month composting process. In the case of charcoal, only the TSA value in apure matrix was relatively lower than that of others, but it increased in 2 months. This indicated that damaging part was changed from outer membrane and enzyme to metabolisms during the composting process. Composting matrix and composting process did not significantly affect inactivation rate of pathogenic bacteria during the process but affected the damaging part of the bacteria.
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Microbial ecology of the Agaricus bisporus mushroom cropping process.
McGee, Conor F
2018-02-01
Agaricus bisporus is the most widely cultivated mushroom species in the world. Cultivation is commenced by inoculating beds of semi-pasteurised composted organic substrate with a pure spawn of A. bisporus. The A. bisporus mycelium subsequently colonises the composted substrate by degrading the organic material to release nutrients. A layer of peat, often called "casing soil", is laid upon the surface of the composted substrate to induce the development of the mushroom crop and maintain compost environmental conditions. Extensive research has been conducted investigating the biochemistry and genetics of A. bisporus throughout the cultivation process; however, little is currently known about the wider microbial ecology that co-inhabits the composted substrate and casing layers. The compost and casing microbial communities are known to play important roles in the mushroom production process. Microbial species present in the compost and casing are known for (1) being an important source of nitrogen for the A. bisporus mycelium, (2) releasing sugar residues through the degradation of the wheat straw in the composted substrate, (3) playing a critical role in inducing development of the A. bisporus fruiting bodies and (4) acting as pathogens by parasitising the mushroom mycelium/crop. Despite a long history of research into the mushroom cropping process, an extensive review of the microbial communities present in the compost and casing has not as of yet been undertaken. The aim of this review is to provide a comprehensive summary of the literature investigating the compost and casing microbial communities throughout cultivation of the A. bisporus mushroom crop.
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Production of compost with bagasse and vinasses for cane crop in Brazil
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, Y.K.; Castro Gomez, R.J.H.
1982-10-01
Recent laboratory experiments have shown that a mixture of bagasse, animal manure and vinasse can be transformed into compost suitable for agriculture. The factors necessary for good composting are discussed, these include the carbon-nitrogen ratio, moisture, aeration and temperature. A mixture of 300 kg cane bagasse and 38 kg poultry manure moistened with vinasse gave the best results.
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Lv, Baoyi; Xing, Meiyan; Yang, Jian; Zhang, Liangbo
2015-12-01
This study aimed to compare the microbial community structures and compositions in composting and vermicomposting processes. We applied 454 high-throughput pyrosequencing to analyze the 16S rRNA gene of bacteria obtained from bio-stabilization of sewage sludge and cattle dung. Results demonstrated that vermicomposting process presented higher operational taxonomic units and bacterial diversity than the composting. Analysis using weighted UniFrac indicated that composting exhibited higher effects on shaping microbial community structure than the vermicomposting. The succession of dominant bacteria was also detected during composting. Firmicutes was the dominant bacteria in the thermophilic phase of composting and shifted to Actinomycetes in the maturing stage. By contrast, Proteobacteria accounted for the highest proportions in the whole process of the vermicomposting. Furthermore, vermicomposting contained more uncultured and unidentified bacteria at the taxonomy level of genus than the composting. In summary, the bacterial community during composting significantly differed from that during vermicomposting. These two techniques played different roles in changing the diversity and composition of microbial communities.
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Sun, Zhao-Yong; Zhang, Jing; Zhong, Xiao-Zhong; Tan, Li; Tang, Yue-Qin; Kida, Kenji
2016-05-01
In the present study, we developed an efficient composting process for the solid fraction of dairy manure (SFDM) using lab-scale systems. We first evaluated the factors affecting the SFDM composting process using different thermophilic phase durations (TPD, 6 or 3days) and aeration rates (AR, 0.4 or 0.2 lmin(-1)kg(-1)-total solid (TS)). Results indicated that a similar volatile total solid (VTS) degradation efficiency (approximately 60%) was achieved with a TPD of 6 or 3days and an AR of 0.4 l min(-1) kg(-1)-TS (hereafter called higher AR), and a TPD of 3days resulted in less N loss caused by ammonia stripping. N loss was least when AR was decreased to 0.2 l min(-1) kg(-1)-TS (hereafter called lower AR) during the SFDM composting process. However, moisture content (MC) in the composting pile increased at the lower AR because of water production by VTS degradation and less water volatilization. Reduced oxygen availability caused by excess water led to lower VTS degradation efficiency and inhibition of nitrification. Adding sawdust to adjust the C/N ratio and decrease the MC improved nitrification during the composing processes; however, the addition of increasing amounts of sawdust decreased NO3(-) concentration in matured compost. When an improved composting reactor with a condensate removal and collection system was used for the SFDM composting process, the MC of the composting pile was significantly reduced, and nitrification was detected 10-14days earlier. This was attributed to the activity of ammonia-oxidizing bacteria (AOB). Highly matured compost could be generated within 40-50days. The VTS degradation efficiency reached 62.0% and the final N content, NO3(-) concentration, and germination index (GI) at the end of the composting process were 3.3%, 15.5×10(3)mg kg(-1)-TS, and 112.1%, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.
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High-rate composting of barley dregs with sewage sludge in a pilot scale bioreactor.
Lu, Li-An; Kumar, Mathava; Tsai, Jen-Chieh; Lin, Jih-Gaw
2008-05-01
The feasibility of high-rate composting of barley dregs and sewage sludge was examined using a pilot scale bioreactor. A central composite design (CCD) was used to optimize the mix ratio of barley dregs/sewage sludge and moisture content. The performance of the bioreactor was monitored as a function of carbon decomposition rate (CDR) and total volatile solids (TVS) loss rate. The optimum range of mix ratio and moisture content was found to be 35-40% and 55-60%, respectively. High CO2 evolution rate (CER) and TVS loss rate were observed after 3 days of the composting and the compost was matured/stable after 7 days. Cardinal temperature model with inflection (CTMI) was used to analyze the compost stability with respect to CER as a parameter of composting efficiency. After examining the phytotoxicity, the compost can be promoted for land application.
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Aerobic Food Waste Composting: Measurement of Green House Gases
NASA Astrophysics Data System (ADS)
Chung, J.
2016-12-01
Greenhouse gases (GHGs) are a major cause of global warming. While food waste composting can reduce the amount of waste being sent to traditional landfills, it also produces GHGs during the process. The objective of this research is to evaluate the GHGs emitted from an aerobic food composting machine, which is used in ISF. The Independent Schools Foundation Academy is a private independent school in Hong Kong with approximately 1500 students. Each academic year, the school produces 27 metric tons of food waste. In November 2013, the school installed a food waste composting system. Over the past 3 years, various improvements, such as installing a bio-filter to reduce the smell of the compost, have been made to the composting process. Meanwhile the compost is used by the primary students, as part of their experiential learning curriculum and organic farming projects. The composting process employs two machines: the Dehydra and A900 Rocket. The Dehydra reduces the mass of the food waste by separating the ground food waste and excessive water. The A900 Rocket, a composter made by Tidy Planet, processes food waste into compost in 14 days. This machine runs in an aerobic process, in which oxygen is used as an input gas and gases, such as carbon dioxide, are released. Carbon Dioxide is one of the greenhouse gases (GHGs). This research focuses on GHGs that are emitted from the A900 Rocket. The data is collected by the Gasmet DX 4015, a Fourier transform infrared spectroscopy (FTIR) multi gas analyser. This equipment measures the concentration (ppm) of different GHGs, including N2O, CO2, CH4, NH3 and CO.
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Zeng, Jianfei; Shen, Xiuli; Sun, Xiaoxi; Liu, Ning; Han, Lujia; Huang, Guangqun
2018-05-01
With the advantages of high treatment capacity and low operational cost, large-scale trough composting has become one of the mainstream composting patterns in composting plants in China. This study measured concentrations of O 2 , CO 2 , CH 4 and NH 3 on-site to investigate the spatial and temporal distribution of pore gas concentrations during mainstream large-scale trough composting in China. The results showed that the temperature in the center of the pile was obviously higher than that in the side of the pile. Pore O 2 concentration rapidly decreased and maintained <5% (in volume) for 38 days or more in both the center and side of the pile and effective O 2 diffusion occurred at most in every two contiguous layers. Pore CO 2 and CH 4 concentrations at each measurement point were positively correlated (0.436 ≤ r ≤ 0.570, P < 0.01) and the concentrations in the side of the pile were obviously lower than those in the center. The top layer exhibited highest pore O 2 concentration and lowest CO 2 and CH 4 concentrations, and the bottom layer was on the contrary. No significant differences in pore NH 3 concentrations between different layers or between different measurement points in the same layer were found. Therefore, mixing the center and the side of the pile when mechanical turning and adjusting the height of the pile according to the physical properties of bulking agents are suggested to optimize the oxygen distribution and promote the composting process during large-scale trough composting when the pile was naturally aerated, which will contribute to improving the current undesirable atmosphere environment in China. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Odor composition analysis and odor indicator selection during sewage sludge composting
Zhu, Yan-li; Zheng, Guo-di; Gao, Ding; Chen, Tong-bin; Wu, Fang-kun; Niu, Ming-jie; Zou, Ke-hua
2016-01-01
ABSTRACT On the basis of total temperature increase, normal dehydration, and maturity, the odor compositions of surface and internal piles in a well-run sewage sludge compost plant were analyzed using gas chromatography–mass spectrometry with a liquid nitrogen cooling system and a portable odor detector. Approximately 80 types of substances were detected, including 2 volatile inorganic compounds, 4 sulfur organic compounds, 16 benzenes, 27 alkanes, 15 alkenes, and 19 halogenated compounds. Most pollutants were mainly produced in the mesophilic and pre-thermophilic periods. The sulfur volatile organic compounds contributed significantly to odor and should be controlled primarily. Treatment strategies should be based on the properties of sulfur organic compounds. Hydrogen sulfide, methyl mercaptan, dimethyl disulfide, dimethyl sulfide, ammonia, and carbon disulfide were selected as core indicators. Ammonia, hydrogen sulfide, carbon disulfide, dimethyl disulfide, methyl mercaptan, dimethylbenzene, phenylpropane, and isopentane were designated as concentration indicators. Benzene, m-xylene, p-xylene, dimethylbenzene, dichloromethane, toluene, chlorobenzene, trichloromethane, carbon tetrachloride, and ethylbenzene were selected as health indicators. According to the principle of odor pollution indicator selection, dimethyl disulfide was selected as an odor pollution indicator of sewage sludge composting. Monitoring dimethyl disulfide provides a highly scientific method for modeling and evaluating odor pollution from sewage sludge composting facilities. Implications: Composting is one of the most important methods for sewage sludge treatment and improving the low organic matter content of many agricultural soils. However, odors are inevitably produced during the composting process. Understanding the production and emission patterns of odors is important for odor control and treatment. Core indicators, concentration indicators, and health indicators provide an index system to odor evaluation. An odor pollution indicator provides theoretical support for further modelling and evaluating odor pollution from sewage sludge composting facilities. PMID:27192607
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Pang, Long; Yang, Peijie; Ge, Liming; Du, Jingjing; Zhang, Hongzhong
2017-02-01
Organophosphate esters (OPEs), widely used as flame retardants and plasticizers, are regarded as emerging pollutants. OPEs are prone to concentrate into residual activated sludge, which might cause secondary pollution if not suitably treated. Composting is an economical and effective approach to make sewage sludge stable and harmless. Therefore, it is essential to develop a novel method for analyzing OPEs in sewage sludge compost samples. However, in the composting process, large amounts of amendments are doped into the sludge to adjust the carbon-nitrogen ratio. Amendment has a strong capacity for adsorption and thus induces a decrease of extraction efficiency. This study developed a novel procedure for determining OPEs in compost samples. Accelerated solvent extraction (ASE) and solid phase extraction (SPE) were used for extracting and concentrating the OPEs from sewage sludge compost samples, and then analyzed by UHPLC-MS/MS. Some parameters were optimized in this study, mainly including the extraction solvent type, extraction temperature, static extraction time, extraction cycles, and flush volume. Under the optimal conditions, the proposed method showed good linearity between 0.50 and 100 μg kg -1 with regression coefficients in the range of 0.9984-0.9998. Detection limits were in the range of 0.02-3 μg kg -1 with standard deviations ranging from 2 to 6%. Acceptable recoveries between 56 and 119% for samples spiked at different concentration levels were achieved. In contrast, the recoveries merely ranged from 24 to 58% by using ultrasonic-assisted extraction. Graphical abstract A comparison of recoveries between ultrasonic-assisted extraction (UAS) and accelerated solvent extraction (ASE) for organophosphate esters from sewage sludge compost samples.
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Jolanun, Banjarata; Kaewkam, Chompoonuch; Bauoon, Orapin; Chiemchaisri, Chart
2014-08-01
Turned windrow composting was investigated as appropriate technology for recycling the wastewater (excluding black liquor) from mulberry pulp and paper handicrafts. Two exterior turned windrows (1.5 m width x 1.5 m height x 2.0 m length) with dry leaves/cow manure/sawdust wet weight ratios of 60:40:0 (Pile A) and 55:40:5 (Pile B) were used for the investigation. Changes in the physical and chemical properties of the compost were examined and a phytotoxicity analysis was performed. A soil incubation test and an informal focus group discussion were also conducted. The results revealed that while both piles met the regulatory processing requirements for further reduced pathogens (>or= 55 degrees C for 15 days or longer), the operation without sawdust (Pile A) not only significantly enhanced the thermophilic temperature regime (P < 0.05) but also yielded the highest amount (1.4 m3 ton-1 pile) of wastewater elimination during the first 2 months of composting. It was found that the constant rates of degradation were 0.006 day- 1 (Pile A) and 0.003 day-1 (Pile B), and no pronounced statistically significant difference in N losses was found (P > 0.05). The germination index of two plant species in both piles varied between 126% and 230% throughout the experiment, and no pronounced differences (P > 0.05) among the samples were found. Addition of the compost significantly improved soil organic matter and pH (7-8), as well as reduced the loss of NO3-N. Local discussion groups were initiated to evaluate the cost-benefits, the potential of wastewater removal, the cooperation of community users and supporters, the compost quality and the potential compost market.
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Odor composition analysis and odor indicator selection during sewage sludge composting.
Zhu, Yan-Li; Zheng, Guo-di; Gao, Ding; Chen, Tong-Bin; Wu, Fang-Kun; Niu, Ming-Jie; Zou, Ke-Hua
2016-09-01
On the basis of total temperature increase, normal dehydration, and maturity, the odor compositions of surface and internal piles in a well-run sewage sludge compost plant were analyzed using gas chromatography-mass spectrometry with a liquid nitrogen cooling system and a portable odor detector. Approximately 80 types of substances were detected, including 2 volatile inorganic compounds, 4 sulfur organic compounds, 16 benzenes, 27 alkanes, 15 alkenes, and 19 halogenated compounds. Most pollutants were mainly produced in the mesophilic and pre-thermophilic periods. The sulfur volatile organic compounds contributed significantly to odor and should be controlled primarily. Treatment strategies should be based on the properties of sulfur organic compounds. Hydrogen sulfide, methyl mercaptan, dimethyl disulfide, dimethyl sulfide, ammonia, and carbon disulfide were selected as core indicators. Ammonia, hydrogen sulfide, carbon disulfide, dimethyl disulfide, methyl mercaptan, dimethylbenzene, phenylpropane, and isopentane were designated as concentration indicators. Benzene, m-xylene, p-xylene, dimethylbenzene, dichloromethane, toluene, chlorobenzene, trichloromethane, carbon tetrachloride, and ethylbenzene were selected as health indicators. According to the principle of odor pollution indicator selection, dimethyl disulfide was selected as an odor pollution indicator of sewage sludge composting. Monitoring dimethyl disulfide provides a highly scientific method for modeling and evaluating odor pollution from sewage sludge composting facilities. Composting is one of the most important methods for sewage sludge treatment and improving the low organic matter content of many agricultural soils. However, odors are inevitably produced during the composting process. Understanding the production and emission patterns of odors is important for odor control and treatment. Core indicators, concentration indicators, and health indicators provide an index system to odor evaluation. An odor pollution indicator provides theoretical support for further modelling and evaluating odor pollution from sewage sludge composting facilities.
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Insights into the redox components of dissolved organic matters during stabilization process.
Yuan, Ying; Xi, Bei-Dou; He, Xiao-Song; Ma, Yan; Zhang, Hui; Li, Dan; Zhao, Xin-Yu
2018-05-01
The changes of dissolved organic matter (DOM) components during stabilization process play significant effects on its redox properties but are little reported. Composting is a stabilization process of DOM, during which both the components and electron transfer capacities (ETCs) of DOM change. The redox components within compost-derived DOM during the stabilization process are investigated in this study. The results show that compost-derived DOM contained protein-like, fulvic-like, and humic-like components. The protein-like component decreases during composting, whereas the fulvic- and humic-like components increase during the process. The electron-donating capacity (EDC), electron-accepting capacity (EAC), and ETC of compost-derived DOM all increase during composting but their correlations with the components presented significant difference. The humic-like components were the main functional component responsible for both EDC and ETC, whereas the protein- and fluvic-like components show negative effects with the EAC, EDC, and ETC, suggesting that the components within DOM have specific redox properties during the stabilization process. These findings are very meaningful for better understanding the geochemical behaviors of DOM in the environment.
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Date palm and the activated sludge co-composting actinobacteria sanitization potential.
El Fels, Loubna; Hafidi, Mohamed; Ouhdouch, Yedir
2016-01-01
The objective of this study was to find a connection between the development of the compost actinobacteria and the potential involvement of antagonistic thermophilic actinomycetes in compost sanitization as high temperature additional role. An abundance of actinobacteria and coliforms during the activated sludge and date palm co-composting is determined. Hundred actinomycete isolates were isolated from the sample collected at different composting times. To evaluate the antagonistic effects of the different recovered actinomycete isolates, several wastewater-linked microorganisms known as human and plant potential pathogens were used. The results showed that 12 isolates have an in vitro inhibitory effect on at least 9 of the indicator microorganisms while only 4 active strains inhibit all these pathogens. The antimicrobial activities of sterilized composting time extracts are also investigated.
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Zhu, Feng-Xiang; Wang, Wei-Ping; Hong, Chun-Lai; Feng, Ming-Guang; Xue, Zhi-Yong; Chen, Xiao-Yang; Yao, Yan-Lai; Yu, Man
2012-07-01
A two-stage composting experiment was performed to utilize pig manure for producing maggots as feed supplement and organic fertilizer. Seven-day composting of 1.8 ton fresh manure inoculated with 9 kg mixture of housefly neonates and wheat bran produced 193 kg aging maggots, followed by 12 week composting to maturity. Reaching the thermophilic phase and final maturity faster was characteristic of the maggot-treated compost compared with the same-size natural compost. Upon the transit of the maggot-treated compost to the second stage, the composting temperature maintained around 55 °C for 9 days and the moisture decreased to ~40%. Moreover, higher pH, faster detoxification and different activity patterns for some microbial enzymes were observed. There was a strong material loss (35% water-soluble carbon and 16% total nitrogen) caused by the maggot culture in the first stage. Our results highlight a higher economic value of pig manure achieved through the two-stage composting without bulking agents. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Degradation of Degradable Starch-Polyethylene Plastics in a Compost Environment †
Johnson, Kenneth E.; Pometto, Anthony L.; Nikolov, Zivko L.
1993-01-01
The degradation performance of 11 types of commercially produced degradable starch-polyethylene plastic compost bags was evaluated in municipal yard waste compost sites at Iowa State University (Ames) and in Carroll, Dubuque, and Grinnell, Iowa. Masterbatches for plastic production were provided by Archer Daniels Midland Co. (Decatur, Ill.), St. Lawrence Starch Co. Ltd. (Mississauga, Ontario, Canada), and Fully Compounded Plastics (Decatur, Ill.). Bags differed in starch content (5 to 9%) and prooxidant additives (transition metals and a type of unsaturated vegetable oil). Chemical and photodegradation properties of each material were evaluated. Materials from St. Lawrence Starch Co. Ltd. and Fully Compounded Plastics photodegraded faster than did materials from Archer Daniels Midland Co., whereas all materials containing transition metals demonstrated rapid thermal oxidative degradation in 70°C-oven (dry) and high-temperature, high-humidity (steam chamber) treatments. Each compost site was seeded with test strips (200 to 800 of each type) taped together, which were recovered periodically over an 8- to 12-month period. At each sampling date, the compost row temperature was measured (65 to 95°C), the location of the recovered test strip was recorded (interior or exterior), and at least four strips were recovered for evaluation. Degradation was followed by measuring the change in polyethylene molecular weight distribution via high-temperature gel permeation chromatography. Our initial 8-month study indicated that materials recovered from the interior of the compost row demonstrated very little degradation, whereas materials recovered from the exterior degraded well. In the second-year study, however, degradation was observed in several plastic materials recovered from the interior of the compost row by month 5 at the Carroll site and almost every material by month 12 at the Grinnell site. The plastic bags collected from each community followed a similar degradation pattern. To our knowledge, this is the first scientific study demonstrating significant polyethylene degradation by these materials in a compost environment. PMID:16348914
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Degradation of degradable starch-polyethylene plastics in a compost environment.
Johnson, K E; Pometto, A L; Nikolov, Z L
1993-04-01
The degradation performance of 11 types of commercially produced degradable starch-polyethylene plastic compost bags was evaluated in municipal yard waste compost sites at Iowa State University (Ames) and in Carroll, Dubuque, and Grinnell, Iowa. Masterbatches for plastic production were provided by Archer Daniels Midland Co. (Decatur, Ill.), St. Lawrence Starch Co. Ltd. (Mississauga, Ontario, Canada), and Fully Compounded Plastics (Decatur, Ill.). Bags differed in starch content (5 to 9%) and prooxidant additives (transition metals and a type of unsaturated vegetable oil). Chemical and photodegradation properties of each material were evaluated. Materials from St. Lawrence Starch Co. Ltd. and Fully Compounded Plastics photodegraded faster than did materials from Archer Daniels Midland Co., whereas all materials containing transition metals demonstrated rapid thermal oxidative degradation in 70 degrees C-oven (dry) and high-temperature, high-humidity (steam chamber) treatments. Each compost site was seeded with test strips (200 to 800 of each type) taped together, which were recovered periodically over an 8- to 12-month period. At each sampling date, the compost row temperature was measured (65 to 95 degrees C), the location of the recovered test strip was recorded (interior or exterior), and at least four strips were recovered for evaluation. Degradation was followed by measuring the change in polyethylene molecular weight distribution via high-temperature gel permeation chromatography. Our initial 8-month study indicated that materials recovered from the interior of the compost row demonstrated very little degradation, whereas materials recovered from the exterior degraded well. In the second-year study, however, degradation was observed in several plastic materials recovered from the interior of the compost row by month 5 at the Carroll site and almost every material by month 12 at the Grinnell site. The plastic bags collected from each community followed a similar degradation pattern. To our knowledge, this is the first scientific study demonstrating significant polyethylene degradation by these materials in a compost environment.
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Spatial nitrifications of microbial processes during composting of swine, cow and chicken manure
Wang, Ke; Li, Weiguang; Li, Xiangkun; Ren, Nanqi
2015-01-01
Composting is a widely-used method to recycle the nutrients in livestock manure for agriculture. The spatial stratifications of microbial processes inside the manure particle that determine organic and nitrogen transformation are virtually unclear. Here, we show the evolution of the interior microenvironment of swine, cow and chicken manure by using microelectrodes during forced-aeration composting. Composting has generally been regarded as an aerobic bioprocess, however, the long-existing of a large anoxic zone inside these manures was confirmed during the active phase in this study. The profile of the oxidation–reduction potential dramatically decreased first and then gradually increased. The spatial difference in the ammonia concentration was not significant, but nitrate concentration continuously decreased with depth. The anoxic condition within the manure particle was demonstrated to be a primary cause of the severe ammonia emission and the long composting period. These founding provided a new insight toward “aerobic” composting process and a sound foundation for the development of efficient composting technology. PMID:26442637
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Spatial nitrifications of microbial processes during composting of swine, cow and chicken manure
NASA Astrophysics Data System (ADS)
Wang, Ke; Li, Weiguang; Li, Xiangkun; Ren, Nanqi
2015-10-01
Composting is a widely-used method to recycle the nutrients in livestock manure for agriculture. The spatial stratifications of microbial processes inside the manure particle that determine organic and nitrogen transformation are virtually unclear. Here, we show the evolution of the interior microenvironment of swine, cow and chicken manure by using microelectrodes during forced-aeration composting. Composting has generally been regarded as an aerobic bioprocess, however, the long-existing of a large anoxic zone inside these manures was confirmed during the active phase in this study. The profile of the oxidation-reduction potential dramatically decreased first and then gradually increased. The spatial difference in the ammonia concentration was not significant, but nitrate concentration continuously decreased with depth. The anoxic condition within the manure particle was demonstrated to be a primary cause of the severe ammonia emission and the long composting period. These founding provided a new insight toward “aerobic” composting process and a sound foundation for the development of efficient composting technology.
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Characterisation of source-separated household waste intended for composting
Sundberg, Cecilia; Franke-Whittle, Ingrid H.; Kauppi, Sari; Yu, Dan; Romantschuk, Martin; Insam, Heribert; Jönsson, Håkan
2011-01-01
Large-scale composting of source-separated household waste has expanded in recent years in the Nordic countries. One problem can be low pH at the start of the process. Incoming biowaste at four composting plants was characterised chemically, physically and microbiologically. The pH of food waste ranged from 4.7 to 6.1 and organic acid concentration from 24 to 81 mmol kg−1. The bacterial diversity in the waste samples was high, with all samples dominated by Gammaproteobacteria, particularly Pseudomonas and Enterobacteria (Escherichia coli, Klebsiella, Enterobacter). Lactic acid bacteria were also numerically important and are known to negatively affect the composting process because the lactic acid they produce lowers the pH, inhibiting other bacteria. The bacterial groups needed for efficient composting, i.e. Bacillales and Actinobacteria, were present in appreciable amounts. The results indicated that start-up problems in the composting process can be prevented by recycling bulk material and compost. PMID:21075618
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Characterisation of source-separated household waste intended for composting.
Sundberg, Cecilia; Franke-Whittle, Ingrid H; Kauppi, Sari; Yu, Dan; Romantschuk, Martin; Insam, Heribert; Jönsson, Håkan
2011-02-01
Large-scale composting of source-separated household waste has expanded in recent years in the Nordic countries. One problem can be low pH at the start of the process. Incoming biowaste at four composting plants was characterised chemically, physically and microbiologically. The pH of food waste ranged from 4.7 to 6.1 and organic acid concentration from 24 to 81 mmol kg(-1). The bacterial diversity in the waste samples was high, with all samples dominated by Gammaproteobacteria, particularly Pseudomonas and Enterobacteria (Escherichia coli, Klebsiella, Enterobacter). Lactic acid bacteria were also numerically important and are known to negatively affect the composting process because the lactic acid they produce lowers the pH, inhibiting other bacteria. The bacterial groups needed for efficient composting, i.e. Bacillales and Actinobacteria, were present in appreciable amounts. The results indicated that start-up problems in the composting process can be prevented by recycling bulk material and compost. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Huhe; Jiang, Chao; Wu, Yanpei; Cheng, Yunxiang
2017-12-01
During composting, the composition of microbial communities is subject to constant change owing to interactions with fluctuating physicochemical parameters. This study explored the changes in bacterial and fungal communities during cattle farm waste composting and aimed to identify and prioritize the contributing physicochemical factors. Microbial community compositions were determined by high-throughput sequencing. While the predominant phyla in the bacterial and fungal communities were largely consistent during the composting, differences in relative abundances were observed. Bacterial and fungal community diversity and relative abundance varied significantly, and inversely, over time. Relationships between physicochemical factors and microbial community compositions were evaluated by redundancy analysis. The variation in bacterial community composition was significantly related to water-soluble organic carbon (WSOC), and pile temperature and moisture (p < .05), while the largest portions of variation in fungal community composition were explained by pile temperature, WSOC, and C/N (p < .05). These findings indicated that those parameters are the most likely ones to influence, or be influenced by the bacterial and fungal communities. Variation partitioning analyses indicated that WSOC and pile temperature had predominant effects on bacterial and fungal community composition, respectively. Our findings will be useful for improving the quality of cattle farm waste composts. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.
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Liu, Ling; Wang, Shuqi; Guo, Xiaoping; Zhao, Tingning; Zhang, Bolin
2018-03-01
A comprehensive characterization of the bacterial diversity associated to thermophilic stages of green waste composting was achieved. In this study, eight different treatments (T1-T8) and three replicated lab-scale green waste composting were carried out to compare the effect of the cellulase (i.e. 0, 2%), microbial inoculum (i.e. 0, 2 and 4%) and particle size (i.e. 2 and 5 mm) on bacterial community structure. Physicochemical properties and bacterial communities of T1-T8 composts were observed, and the bacterial structure and diversity were examined by high-throughput sequencing via a MiSeq platform. The results showed that the most abundant phyla among the treatments were the Firmicutes, Chloroflexi and Proteobacteria. The shannon index and non-metric multidimensional scaling (NMDS) showed higher bacterial abundance and diversity at the metaphase of composting. Comparing with 5-mm treatments, particle size of 2-mm had a richer diversity of bacterial communities. The addition of cellulase and a microbial inoculum could promote the fermentation temperature, reduce the compost pH and C/N ratio and result in higher GI index. The humic substance (HS) and humic acid (HA) contents for 2-mm particle size treatments were higher than those of 5-mm treatments. Canonical correspondence analysis suggested that differences in bacterial abundance and diversity significantly correlated with HA, E 4 /E 6 and temperature, and the relationship between bacterial diversity and environmental parameters was affected by composting stages. Based on these results, the application of cellulase to promote green waste composting was feasible, and particle size was identified as a potential control of composting physicochemical properties and bacterial diversity. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Zhong, Jia; Wei, Yuan-Song; Zhao, Zhen-Feng; Ying, Mei-Juan; Zhou, Guo-Sheng; Xiong, Jian-Jun; Liu, Pei-Cai; Ge, Zhen; Ding, Gang-Qiang
2013-11-01
There is a great uncertainty of greenhouse gas (GHG) reduction and nitrogen conservation from the full process of sludge composting and land application of compost in China due to the lack of emission data of GHG such as N2O and CH4 and ammonia (NH3). The purpose of this study is to get emission characteristics of GHGs and NH3 from the full process with on-site observation. Results showed that the total GHG emission factor from full process of the turning windrow (TW) system (eCO2/dry sludge, 196.21 kg x t(-1)) was 1.61 times higher of that from the ATP system. Among the full process, N2O was mostly from the land application of compost, whereas CH4 mainly resulted from the sludge composting. In the sludge composting of ATP, the GHG emission equivalence of the ATP (eCO2/dry sludge, 12.47 kg x t(-1) was much lower than that of the TW (eCO2/dry sludge, 86.84 kg x t(-1)). The total NH3 emission factor of the TW (NH3/dry sludge, 6.86 kg x t(-1)) was slightly higher than that of the ATP (NH3/dry sludge, 6.63 kg x t(-1)). NH3 was the major contributor of nitrogen loss in the full process. During the composting, the nitrogen loss as NH3 from both TW and ATP was nearly the same as 30% of TN loss from raw materials, and the N and C loss caused by N2O and CH4 were negligible. These results clearly showed that the ATP was a kind of environmentally friendly composting technology.
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9 CFR 82.7 - Interstate movement of manure and litter from a quarantined area.
Code of Federal Regulations, 2014 CFR
2014-01-01
... arrival of the manure and litter at the destination listed on the permit. (b) Compost derived from manure... to the composting site at the same time; (5) Following the composting process, the composted manure... resulting compost must be transported either in a previously unused container or in a container that has...
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Jara-Samaniego, J.; Pérez-Murcia, M. D.; Bustamante, M. A.; Paredes, C.; Pérez-Espinosa, A.; Gavilanes-Terán, I.; López, M.; Marhuenda-Egea, F. C.; Brito, H.; Moral, R.
2017-01-01
Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents. PMID:28727757
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Jara-Samaniego, J; Pérez-Murcia, M D; Bustamante, M A; Paredes, C; Pérez-Espinosa, A; Gavilanes-Terán, I; López, M; Marhuenda-Egea, F C; Brito, H; Moral, R
2017-01-01
Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents.
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Fayolle-Guichard, Françoise; Lombard, Vincent; Hébert, Agnès; Coutinho, Pedro M.; Groppi, Alexis; Barre, Aurélien; Henrissat, Bernard
2016-01-01
Cost-effective biofuel production from lignocellulosic biomass depends on efficient degradation of the plant cell wall. One of the major obstacles for the development of a cost-efficient process is the lack of resistance of currently used fungal enzymes to harsh conditions such as high temperature. Adapted, thermophilic microbial communities provide a huge reservoir of potentially interesting lignocellulose-degrading enzymes for improvement of the cellulose hydrolysis step. In order to identify such enzymes, a leaf and wood chip compost was enriched on a mixture of thermo-chemically pretreated wheat straw, poplar and Miscanthus under thermophile conditions, but in two different set-ups. Unexpectedly, metagenome sequencing revealed that incubation of the lignocellulosic substrate with compost as inoculum in a suspension culture resulted in an impoverishment of putative cellulase- and hemicellulase-encoding genes. However, mimicking composting conditions without liquid phase yielded a high number and diversity of glycoside hydrolase genes and an enrichment of genes encoding cellulose binding domains. These identified genes were most closely related to species from Actinobacteria, which seem to constitute important players of lignocellulose degradation under the applied conditions. The study highlights that subtle changes in an enrichment set-up can have an important impact on composition and functions of the microcosm. Composting-like conditions were found to be the most successful method for enrichment in species with high biomass degrading capacity. PMID:27936240
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Zhong, Xiao-Zhong; Ma, Shi-Chun; Wang, Shi-Peng; Wang, Ting-Ting; Sun, Zhao-Yong; Tang, Yue-Qin; Deng, Yu; Kida, Kenji
2018-01-01
The present study compared the development of various physicochemical properties and the composition of microbial communities involved in the composting process in the solid fraction of dairy manure (SFDM) with a sawdust-regulated SFDM (RDM). The changes in several primary physicochemical properties were similar in the two composting processes, and both resulted in mature end-products within 48days. The bacterial communities in both composting processes primarily comprised Proteobacteria and Bacteroidetes. Firmicutes were predominant in the thermophilic phase, whereas Chloroflexi, Planctomycetes, and Nitrospirae were more abundant in the final mature phase. Furthermore, the succession of bacteria in both groups proceeded in a similar pattern, suggesting that the effects of the bulking material on bacterial dynamics were minor. These results demonstrate the feasibility of composting using only the SFDM, reflected by the evolution of physicochemical properties and the microbial communities involved in the composting process. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Chen, Wei; Liao, Xindi; Wu, Yinbao; Liang, Juan Boo; Mi, Jiandui; Huang, Jinjie; Zhang, Heng; Wu, Yu; Qiao, Zhifen; Li, Xi; Wang, Yan
2017-03-01
Biochar, because of its unique physiochemical properties and sorption capacity, may be an ideal amendment in reducing gaseous emissions during composting process but there has been little information on the potential effects of different types of biochar on undesired gaseous emissions. The objective of this study was to examine the ability and mechanism of different types of biochar, as co-substrate, in mitigating gaseous emission from composting of layer hen manure. The study was conducted in small-scale laboratory composters with the addition of 10% of one of the following biochars: cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar. The results showed that the cumulative NH 3 production was significantly reduced by 24.8±2.9, 9.2±1.3, 20.1±2.6, 14.2±1.6, 11.8±1.7% (corrected for initial total N) in the cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar treatments, respectively, compared to the control. Total CH 4 emissions was significantly reduced by 26.1±2.3, 15.5±2.1, 22.4±3.1, 17.1±2.1% (corrected for the initial total carbon) for cornstalk biochar, bamboo biochar, woody biochar and coir biochar treatments than the control. Moreover, addition of cornstalk biochar increased the temperature and NO 3 - -N concentration and decreased the pH, NH 4 + -N and organic matter content throughout the composting process. The results suggested that total volatilization of NH 3 and CH 4 in cornstalk biochar treatment was lower than the other treatments; which could be due to (i) decrease of pH and higher nitrification, (ii) high sorption capacity for gases and their precursors, such as ammonium nitrogen from composting mixtures, because of the higher surface area, pore volumes, total acidic functional groups and CEC of cornstalk biochar. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Effectiveness of three bulking agents for food waste composting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adhikari, Bijaya K.; Barrington, Suzelle; Martinez, Jose
2009-01-15
Rather than landfilling, composting the organic fraction of municipal solid wastes recycles the waste as a safe and nutrient enriched soil amendment, reduces emissions of greenhouse gases and generates less leachate. The objective of this project was to investigate the composting effectiveness of three bulking agents, namely chopped wheat (Triticum) straw, chopped mature hay consisting of 80% timothy (milium) and 20% clover (triphullum) and pine (pinus) wood shavings. These bulking agents were each mixed in duplicates at three different ratios with food waste (FW) and composted for 10 days using prototype in-vessel composters to observe their temperature and pH trends.more » Then, each mixture was matured in vertical barrels for 56 days to measure their mass loss and final nutrient content and to visually evaluate their level of decomposition. Chopped wheat straw (CWS) and chopped hay (CH) were the only two formulas that reached thermophilic temperatures during the 10 days of active composting when mixed with FW at a wet mass ratio of 8.9 and 8.6:1 (FW:CWS and FW:CH), respectively. After 56 days of maturation, these two formulas were well decomposed with no or very few recognizable substrate particles, and offered a final TN exceeding the original. Wood shavings (WS) produced the least decomposed compost at maturation, with wood particles still visible in the final product, and with a TN lower than the initial. Nevertheless, all bulking agents produced compost with an organic matter, TN, TP and TK content suitable for use as soil amendment.« less
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Advantages and risks of using steel slag in preparing composts from raw organic waste.
Tu, Xuefei; Aneksampant, Apichaya; Kobayashi, Shizusa; Tanaka, Atsushi; Nishimoto, Ryo; Fukushima, Masami
2017-01-02
It had been reported that iron and manganese oxides in steel slag enhanced the production of humic acid (HA) from low-molecular-weight compounds, such as phenolic acids, amino acids, and saccharides. In the present study, this function of steel slag was applied to the composting of raw organic wastes (ROWs). The degree of humification of HAs is an important factor in evaluating compost quality. Thus, HAs were extracted from the prepared composts and the humification parameters were determined, in terms of elemental compositions, acidic functional group contents, molecular weights, spectroscopic parameters from UV-vis absorption and 13 C NMR spectra. The timing for adding steel slag affected the degree of humification of HAs in the composts. The weight average molecular weight of a HA when slag was added initially (29 kDa) was significantly higher than when slag was added after elevating the temperature of the compost pile (17-18 kDa). These results show that ROWs are decomposed to low-molecular-weight compounds after the pile temperature is elevated and the presence of slag enhances the polycondensation of these compounds to produce HAs with a higher degree of humification. Because the slag used in the present study contained several-tens ng g -1 to several μg g -1 of toxic elements (B, Cu, Cr, and Zn), leaching tests for these elements from the prepared composts were carried out. Levels for leaching boron from composts prepared by adding slag (0.2-0.4 mg L -1 ) were obviously higher than the corresponding levels without slag (0.05 mg L -1 ).
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Hu, Weitong; Zheng, Guanyu; Fang, Di; Cui, Chunhong; Liang, Jianru; Zhou, Lixiang
2015-10-01
Sludge bioleaching technology with Acidithiobacillus species has been commercially adopted for improving advanced dewatering of sludge in China since 2010. However, up to now, little information on bioleached dewatered sludge (BS) composting is available. Here, we report the changes of physicochemical and biological properties in BS composting and evaluate compost product quality compared to conventional dewatered sludge (CS) composting in an engineering scale composting facility. The results showed that the amount of bulking agents required in BS composting was only about 10% of CS composting to obtain optimum moisture content, reducing about 700 kg bulking agents per ton fresh sludge. pH of BS composting mixture was slightly lower consistently by about 0.2-0.3 pH units than that in CS mixture in the first 30 days. Organic matter biodegradation in BS system mainly occurred in the first 9 days of composting. In spite of higher content of NH4(+)-N was found in BS mixture in related to CS mixture; unexpectedly the cumulative ammonia volatilization in the former was only 51% of the latter, indicating that BS composting drastically reduced nitrogen loss. Compared to CS composting system, the relative lower pH, the higher intensity of microbial assimilation, and the presence of water soluble Fe in BS system might jointly reduce ammonia volatilization. Consequently, BS compost product exhibited higher fertilizer values (N+P2O5+K2O=8.38%) as well as lower heavy metal levels due to the solubilization of sludge-borne heavy metals during bioleaching process. Therefore, composting of BS possesses more advantages over the CS composting process. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Coffee husk composting: An investigation of the process using molecular and non-molecular tools
Shemekite, Fekadu; Gómez-Brandón, María; Franke-Whittle, Ingrid H.; Praehauser, Barbara; Insam, Heribert; Assefa, Fassil
2014-01-01
Various parameters were measured during a 90-day composting process of coffee husk with cow dung (Pile 1), with fruit/vegetable wastes (Pile 2) and coffee husk alone (Pile 3). Samples were collected on days 0, 32 and 90 for chemical and microbiological analyses. C/N ratios of Piles 1 and 2 decreased significantly over the 90 days. The highest bacterial counts at the start of the process and highest actinobacterial counts at the end of the process (Piles 1 and 2) indicated microbial succession with concomitant production of compost relevant enzymes. Denaturing gradient gel electrophoresis of rDNA and COMPOCHIP microarray analysis indicated distinctive community shifts during the composting process, with day 0 samples clustering separately from the 32 and 90-day samples. This study, using a multi-parameter approach, has revealed differences in quality and species diversity of the three composts. PMID:24369846
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Ventorino, Valeria; Parillo, Rita; Testa, Antonino; Viscardi, Sharon; Espresso, Francesco; Pepe, Olimpia
2016-01-15
Making compost from chestnut lignocellulosic waste is a possible sustainable management strategy for forests that employs a high-quality renewable organic resource. Characterization of the microbiota involved in composting is essential to better understand the entire process as well as the properties of the final product. Therefore, this study investigated the microbial communities involved in the composting of chestnut residues obtained from tree cleaning and pruning. The culture-independent approach taken highlighted the fact that the microbiota varied only slightly during the process, with the exception of those of the starting substrate and mature compost. The statistical analysis indicated that most of the bacterial and fungal species in the chestnut compost persisted during composting. The dominant microbial population detected during the process belonged to genera known to degrade recalcitrant lignocellulosic materials. Specifically, we identified fungal genera, such as Penicillium, Fusarium, Cladosporium, Aspergillus and Mucor, and prokaryotic species affiliated with Bacilli, Actinobacteria, Flavobacteria and γ-Proteobacteria. The suppressive properties of compost supplements for the biocontrol of Sclerotinia minor and Rhizoctonia solani were also investigated. Compared to pure substrate, the addition of compost to the peat-based growth substrates resulted in a significant reduction of disease in tomato plants of up to 70 % or 51 % in the presence of Sclerotinia minor or Rhizoctonia solani, respectively. The obtained results were related to the presence of putative bio-control agents and plant growth-promoting rhizobacteria belonging to the genera Azotobacter, Pseudomonas, Stenotrophomonas, Bacillus, Flavobacterium, Streptomyces and Actinomyces in the chestnut compost. The composting of chestnut waste may represent a sustainable agricultural practice for disposing of lignocellulosic waste by transforming it into green waste compost that can be used to improve the fitness of agricultural plants. Copyright © 2015 Elsevier Ltd. All rights reserved.
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ASSESSMENT OF THE BACTERIOLOGICAL QUALITY OF COMPOST FROM A YARD WASTE PROCESSING FACILITY
Citizen concern over possible pathogenic microorganism contamination in compost and in a runoff collection pond prompted a U.S. Environmental Protection Agency (EPA) investigation. One out of eight samples collected from the distribution pile at a yard waste compost processing f...
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Removal of five fluoroquinolone antibiotics during broiler manure composting.
Yang, Bing; Meng, Lei; Xue, Nandong
2018-02-01
Composting is a cost-effective approach for the removal of antibiotics from the environment; however, the consequence of this approach on fluoroquinolone antibiotics is limited. The fate of five representative fluoroquinolone antibiotics, namely ciprofloxacin, enrofloxacin, lomefloxacin, norfloxacin, and sarafloxacin, was investigated in a pilot-scale composting of broiler manure over 42 days. The effect of antibiotic concentrations (at a dose of 15, 30, or 60 mg/kg for each and a control without antibiotic addition) on the composting process was also assessed. The 42-day composting showed 45.3-75.4% of antibiotic removal with species-specific patterns. However, the observed variations in such removal among both antibiotics concentrations and composting times were not significant in most cases, possibly indicating a slight side-effect of the tested antibiotic concentrations on the composting process. To the best of our knowledge, this study is among few studies with a focus on the persistence of fluoroquinolone antibiotics during a pilot-scale composting, which warrants further study in regards to the mechanism underlying the removal of these compounds during composting.
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Whole Animal Composting of Beef Cattle
USDA-ARS?s Scientific Manuscript database
Composting is the natural decomposition of organic materials by microorganisms that require oxygen. Although many aspects of composting are not exact, there are several factors that affect the success of the composting process which are 1) carbon and nitrogen ratios (C:N ratio), 2) moisture content...
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ERIC Educational Resources Information Center
Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.
Composting is a way of using organic wastes from yards and kitchens to help plants grow. This book discusses how composting happens in nature, the classification of composting methods, and their characteristics. Examples of containers for aerobic/anaerobic decomposition are introduced along with sample activities. The process of aerobic/anaerobic…
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Luo, Wei; Chen, Tong-bin; Gao, Ding; Zheng, Yu-qi; Zheng, Guo-di
2004-03-01
The experiment of co-composting of sewage sludge and pig manure was studied. The moisture contents were 50.82%-60.87% at the stage of temperature rising and 38.7%-52.17% at the stage of thermophilic fermentation, and the stratification of moisture content were not obvious for both stages because the door, the internal wall and the depth of the composting bay had little effect on the stratification. At the stage of cooling, the moisture content was 24.54%-49.39%, and the stratification of moisture content was remarkable as the door, the internal wall and the depth of the composting bay had great influence on it. At the stage of maturity, the moisture content was 19.18%-49.34%, and the stratification of moisture weakened, for which the door and the internal wall were mainly responsible. At the different composting stage, the degree of difference of moisture content on the profiles of the pile was of the order: maturity stage > cooling stage > thermophilic stage = temperature rising stage, and the moisture content in the pile was as follows: the lower > the middle > the upper. The relation between moisture content and composting time meeted with two-order kinetics equation.
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Carbohydrate composition of compost during composting and mycelium growth of Agaricus bisporus.
Jurak, Edita; Kabel, Mirjam A; Gruppen, Harry
2014-01-30
Changes of plant cell wall carbohydrate structures occurring during the process to make suitable compost for growth of Agaricus bisporus are unknown. In this paper, composition and carbohydrate structures in compost samples collected during composting and mycelium growth were analyzed. Furthermore, different extracts of compost samples were prepared with water, 1M and 4M alkali and analyzed. At the beginning of composting, 34% and after 16 days of mycelium growth 27% of dry matter was carbohydrates. Carbohydrate composition analysis showed that mainly cellulose and poorly substituted xylan chains with similar amounts and ratios of xylan building blocks were present in all phases studied. Nevertheless, xylan solubility increased 20% over the period of mycelium growth indicating partial degradation of xylan backbone. Apparently, degradation of carbohydrates occurred over the process studied by both bacteria and fungi, mainly having an effect on xylan-chain length and solubility. Copyright © 2013 Elsevier Ltd. All rights reserved.
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A process-based model for cattle manure compost windrows: Model description
USDA-ARS?s Scientific Manuscript database
Composting is an alternative management practice for handling and storing manure in intensive cattle production systems. With composting, cattle manure is converted into a soil amendment with improved nutrient and physical properties and is easier to handle. Despite its benefits, composting can prod...
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Chen, Yaoning; Ma, Shuang; Li, Yuanping; Yan, Ming; Zeng, Guangming; Zhang, Jiachao; Zhang, Jie; Tan, Xuebin
2016-11-01
This paper studied the degradation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in contaminated soil under composting and natural conditions, respectively. BDE-47 residue in agricultural waste-composting pile was determined during 45-day composting. The microbial communities were determined by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and the relationships between the DGGE results and physico-chemical parameters were evaluated by redundancy analysis (RDA) and heatmap-clustering analysis. The results showed that the degradation rate of BDE-47 was significantly higher in agricultural waste-composting pile compared with control group, which was enhanced up to almost 15 % at the end of composting. There were different environmental factors which affected the distribution of composting bacterial and fungal communities. The bacterial community composition was more significantly affected by the addition of BDE-47 compared with other physico-chemical parameters, and BDE-47 had stronger influences on bacterial community than fungal community during the composting. Meanwhile, the most variation in distribution of fungal community was explained by pile temperature.
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Zhang, Difang; Luo, Wenhai; Yuan, Jing; Li, Guoxue; Luo, Yuan
2017-10-01
This study investigated the effect of calcium superphosphate on compost maturity and gaseous emissions during pig manure composting with woody peat as the bulking agent. Two treatments were conducted with or without the addition of calcium superphosphate (10% dry weight of the composting mass), which were denoted as the control and superphosphate-amended treatment, respectively. Results show that the composting temperature of both treatments was higher than 50°C for more than 5days, which is typically required for pathogen destruction during manure composting. Compared to the control treatment, the superphosphate-amended treatment increased the emission of nitrogen oxide, but reduced the emission of methane, ammonia and hydrogen sulfide by approximately 35.5%, 37.9% and 65.5%, respectively. As a result, the total greenhouse gas (GHG) emission during manure composting was reduced by nearly 34.7% with the addition of calcium superphosphate. The addition of calcium superphosphate increased the content of humic acid (indicated by E 4 /E 6 ratio). Nevertheless, the superphosphate-amended treatment postponed the biological degradation of organic matter and produced the mature compost with a higher electrical conductivity in comparison with the control treatment. Copyright © 2017. Published by Elsevier Ltd.
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Faverial, Julie; Cornet, Denis; Paul, Jacky; Sierra, Jorge
2016-01-01
Previous studies indicated that the quality of tropical composts is poorer than that of composts produced in temperate regions. The aim of this study was to test the type of manure, the use of co-composting with green waste, and the stabilization method for their ability to improve compost quality in the tropics. We produced 68 composts and vermicomposts that were analysed for their C, lignin and NPK contents throughout the composting process. Bayesian networks were used to assess the mechanisms controlling compost quality. The concentration effect, for C and lignin, and the initial blend quality, for NPK content, were the main factors affecting compost quality. Cattle manure composts presented the highest C and lignin contents, and poultry litter composts exhibited the highest NPK content. Co-composting improved quality by enhancing the concentration effect, which reduced the impact of C and nutrient losses. Vermicomposting did not improve compost quality; co-composting without earthworms thus appears to be a suitable stabilization method under the conditions of this study because it produced high quality composts and is easier to implement.
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Assessment of bacterial diversity during composting of agricultural byproducts
2013-01-01
Background Composting is microbial decomposition of biodegradable materials and it is governed by physicochemical, physiological and microbiological factors. The importance of microbial communities (bacteria, actinomycetes and fungi) during composting is well established. However, the microbial diversity during composting may vary with the variety of composting materials and nutrient supplements. Therefore, it is necessary to study the diversity of microorganisms during composting of different agricultural byproducts like wheat bran, rice bran, rice husk, along with grass clippings and bulking agents. Here it has been attempted to assess the diversity of culturable bacteria during composting of agricultural byproducts. Results The culturable bacterial diversity was assessed during the process by isolating the most prominent bacteria. Bacterial population was found to be maximum during the mesophilic phase, but decreased during the thermophilic phase and declined further in the cooling and maturation phase of composting. The bacterial population ranged from 105 to 109 cfu g-1 compost. The predominant bacteria were characterized biochemically, followed by 16S rRNA gene sequencing. The isolated strains, both Gram-positive and Gram-negative groups belonged to the order Burkholderiales, Enterobacteriales, Actinobacteriales and Bacillales, which includes genera e.g. Staphylococcus, Serratia, Klebsiella, Enterobacter, Terribacillus, Lysinibacillus Kocuria, Microbacterium, Acidovorax and Comamonas. Genera like Kocuria, Microbacterium, Acidovorax, Comamonas and some new species of Bacillus were also identified for the first time from the compost made from agricultural byproducts. Conclusion The use of appropriate nitrogen amendments and bulking agents in composting resulted in good quality compost. The culture based strategy enabled us to isolate some novel bacterial isolates like Kocuria, Microbacterium, Acidovorax and Comamonas first time from agro-byproducts compost. These bacteria can be used as potential compost inoculants for accelerating composting process. PMID:23651653
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Brimo, Khaled; Ouvrard, Stéphanie; Houot, Sabine; Lafolie, François; Garnier, Patricia
2018-03-01
A new model that was able to simulate the behaviours of polycyclic aromatic hydrocarbons (PAH) during composting and after the addition of the composts to agricultural soil is presented here. This model associates modules that describe the physical, biological and biochemical processes involved in PAH dynamics in soils, along with a module describing the compost degradation resulting in PAH release. The model was calibrated from laboratory incubations using three 14 C-PAHs, phenanthrene, fluoranthene and benzo(a)pyrene, and three different composts consisting of two mature and one non-mature composts. First, the labelled PAHs were added to the compost over 28days, and spiked composts were then added to the soil over 55days. The model calculates the proportion of biogenic and physically bound residues in the non-extractable compartment of PAHs at the end of the compost incubation to feed the initial conditions of the model for soil amended with composts. For most of the treatments, a single parameter set enabled to simulate the observed dynamics of PAHs adequately for all the amended soil treatments using a Bayesian approach. However, for fluoranthene, different parameters that were able to simulate the growth of a specific microbial biomass had to be considered for mature compost. Processes that occurred before the compost application to the soil strongly influenced the fate of PAHs in the soil. Our results showed that the PAH dissipation during compost incubation was higher in mature composts because of the higher specific microbial activity, while the PAH dissipation in amended soil was higher in the non-mature compost because of the higher availability of PAHs and the higher co-metabolic microbial activity. Copyright © 2017 Elsevier B.V. All rights reserved.
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Xiao, Ran; Awasthi, Mukesh Kumar; Li, Ronghua; Park, Jonghwan; Pensky, Scott M; Wang, Quan; Wang, Jim J; Zhang, Zengqiang
2017-12-01
In recent years, considerable studies have been devoted to investigating the effect of biochar application on organic solid waste composting. This review provides an up-to-date overview of biochar amendment on composting processes and compost quality. Biochar production, characteristics, and its application coupled with the basic concepts of composting are briefly introduced before detailing the effects of biochar addition on composting. According to recent studies, biochar has exhibited great potential for enhancing composting. It is evident that biochar addition in composting can: (1) improve compost mixture physicochemical properties, (2) enhance microbial activities and promote organic matter decomposition, (3) reduce ammonia (NH 3 ) and greenhouse gas (GHG) emissions, and (4) upgrade compost quality by increasing the total/available nutrient content, enhancing maturity, and decreasing phytotoxicity. Despite that, further research is needed to explore the mechanism of biochar addition on composting and to evaluate the agricultural and environmental performances of co-composted biochar compost. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Wei, Huawei; Wang, Liuhong; Hassan, Muhammad; Xie, Bing
2018-05-01
Illumina MiSeq sequencing and phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) were applied to study the dynamic changes and effects of microbial community structures as well as the metabolic function of bacterial community in maize straw composting process. Results showed that humic acid contents in loosely combined humus (HA1) and stably combined humus (HA2) increased after composting and Staphylococcus, Cellulosimicrobium and Ochrobactrum possibly participated in the transformation of the process. The bacterial communities differed in different stages of the composting. Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria were reported the dominant phyla throughout the process and the relative abundance of the dominant phyla varied significantly (p < 0.05) over time. Moreover, the total phosphorus (TP) had the greatest influence on the microbial community structure among C/N ratio, available phosphorus (AP) and humic substances. Metabolism, cellular processes and environmental information processing might be the primary functions of microbial community during the composting. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Wu, Duo; Zhang, Chunyan; Lü, Fan; Shao, Liming; He, Pinjing
2014-06-01
The application of on-site waste treatment significantly reduces the need for expensive waste collection and transportation in rural areas; hence, it is considered of fundamental importance in developing countries. In this study, the effects of in-field operation of two types of mini-scale on-site solid waste treatment facilities on de-centralized communities, one using mesophilic two-phase anaerobic digestion combined with composting (TPAD, 50 kg/d) and another using decentralized composting (DC, 0.6-2 t/d), were investigated. Source-separated collection was applied to provide organic waste for combined process, in which the amount of waste showed significant seasonal variation. The highest collection amount was 0.18 kg/capital day and 0.6 kg/household day. Both sites showed good performance after operating for more than 6 months, with peak waste reduction rates of 53.5% in TPAD process and 63.2% in DC process. Additionally, the windrow temperature exceeded 55 °C for >5 days, indicating that the composting products from both facilities were safe. These results were supported by 4 days aerobic static respiration rate tests. The emissions were low enough to avoid any impact on nearby communities (distance <100 m). Partial energy could be recovered by the combined process but with complicated operation. Hence, the choice of process must be considered in case separately. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Mtimkulu, Y; Meyer, A H; Mulidzi, A R; Shange, P L; Nchu, F
2017-01-01
Waste management in winery and distillery industries faces numerous disposal challenges as large volumes of both liquid and solid waste by-products are generated yearly during cellar practices. Composting has been suggested as a feasible option to beneficiate solid organic waste. This incentivized the quest for efficient composting protocols to be put in place. The objective of this study was to experiment with different composting strategies for spent winery solid waste. Compost materials consisting of chopped pruning grape stalks, skins, seed and spent wine filter material consisting of a mixture of organic and inorganic expend ingredients were mixed in compost heaps. The filter material component varied (in percentage) among five treatments: T1 (40%) lined, T2 (20%) lined, T3 (0%) lined, T4 (40%) ground material, lined and T5 (40%) unlined. Composting was allowed to proceed under open field conditions over 12months, from autumn to summer. Indicators such as temperature, moisture, enzyme activities, microbial counts, pH, and C/N ratio, were recorded. Generally, season (df=3, 16, P<0.05) had significant effects (df=1, 3, P<0.05) on heap temperature and moisture in all treatments. Similarly, microorganisms (actinobacteria and heterotrophs) varied significantly in all treatments in response to seasonal change (df=3, 16; P<0.05). Enzyme activities fluctuated in accordance with seasonal factors and compost maturity stages, with phosphatases, esterases, amino-peptidases, proteases and glycosyl-hydrolases being most prominent. Compared to treatments T2 and T3, compost treatments with higher percentage waste filter materials (T1, T4 and T5) had higher N (16,100-21,300mg/kg), P (1500-2300mg/kg), K (19,800-28,200mg/kg), neutral pH, and lower C/N ratios (13:1-10:1), which were also comparable with commercially produced composts. Filter materials therefore, appears to be a vital ingredient for composting of winery solid waste. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Characterization of the biosolids composting process by hyperspectral analysis.
Ilani, Talli; Herrmann, Ittai; Karnieli, Arnon; Arye, Gilboa
2016-02-01
Composted biosolids are widely used as a soil supplement to improve soil quality. However, the application of immature or unstable compost can cause the opposite effect. To date, compost maturation determination is time consuming and cannot be done at the composting site. Hyperspectral spectroscopy was suggested as a simple tool for assessing compost maturity and quality. Nevertheless, there is still a gap in knowledge regarding several compost maturation characteristics, such as dissolved organic carbon, NO3, and NH4 contents. In addition, this approach has not yet been tested on a sample at its natural water content. Therefore, in the current study, hyperspectral analysis was employed in order to characterize the biosolids composting process as a function of composting time. This goal was achieved by correlating the reflectance spectra in the range of 400-2400nm, using the partial least squares-regression (PLS-R) model, with the chemical properties of wet and oven-dried biosolid samples. The results showed that the proposed method can be used as a reliable means to evaluate compost maturity and stability. Specifically, the PLS-R model was found to be an adequate tool to evaluate the biosolids' total carbon and dissolved organic carbon, total nitrogen and dissolved nitrogen, and nitrate content, as well as the absorbance ratio of 254/365nm (E2/E3) and C/N ratios in the dry and wet samples. It failed, however, to predict the ammonium content in the dry samples since the ammonium evaporated during the drying process. It was found that in contrast to what is commonly assumed, the spectral analysis of the wet samples can also be successfully used to build a model for predicting the biosolids' compost maturity. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Santos, Cátia; Fonseca, João; Aires, Alfredo; Coutinho, João; Trindade, Henrique
2017-01-01
The use of spent coffee grounds (SCG) in composting for organic farming is a viable way of valorising these agro-industrial residues. In the present study, four treatments with different amounts of spent coffee grounds (SCG) were established, namely, C 0 (Control), C 10 , C 20 and C 40 , containing 0, 10, 20 and 40% of SCG (DM), respectively; and their effects on the composting process and the end-product quality characteristics were evaluated. The mixtures were completed with Acacia dealbata L. shoots and wheat straw. At different time intervals during composting, carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) emissions were measured and selected physicochemical characteristics of the composts were evaluated. During the composting process, all treatments showed a substantial decrease in total phenolics and total tannins, and an important increase in gallic acid. Emissions of greenhouse gases were very low and no significant difference between the treatments was registered. The results indicated that SCG may be successfully composted in all proportions. However C 40 , was the treatment which combined better conditions of composting, lower GHG emissions and better quality of end product. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Bianchi, Biagio; Papajova, Ingrid; Tamborrino, Rosanna; Ventrella, Domenico; Vitti, Carolina
2015-01-01
In this study we have observed the effects of using rabbit manure and slaughtering by-products in a composting process. Three piles of this material, 4700 kg each, with different amount and C/N ratio, have been investigated and experimental tests were carried out in an industrial horizontal axe reactor using a prototype of turning machine. The composting time lasted 85 days; 2 experimental cycles were conducted: one in Winter and one in Summer. In the Winter test, mesophilic reaction started only in the control mixture (animal manure + slaughtering by-products without straw). It is noteworthy that, the 3 investigated mixtures produced soil amendment by compost with good agronomical potential but with parameters close to the extreme limits of the law. In the Summer test, there was thermophilic fermentation in all mixtures and a better quality compost was obtained, meeting all the agronomic and legislative constraints. For each pile, we examined the progression of fermentation process and thus the plant limitations that did not allow a correct composting process. The results obtained in this study are useful for the development of appropriate mixtures, machines, and plants assuring continuance and reliability in the composting of the biomass coming from rabbit industry.
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Viaene, J; Van Lancker, J; Vandecasteele, B; Willekens, K; Bijttebier, J; Ruysschaert, G; De Neve, S; Reubens, B
2016-02-01
Maintaining and increasing soil quality and fertility in a sustainable way is an important challenge for modern agriculture. The burgeoning bioeconomy is likely to put further pressure on soil resources unless they are managed carefully. Compost has the potential to be an effective soil improver because of its multiple beneficial effects on soil quality. Additionally, it fits within the bioeconomy vision because it can valorize biomass from prior biomass processing or valorize biomass unsuitable for other processes. However, compost is rarely used in intensive agriculture, especially in regions with high manure surpluses. The aim of this research is to identify the barriers to on-farm composting and the application of compost in agriculture, using a mixed method approach for the case of Flanders. The significance of the 28 identified barriers is analyzed and they are categorized as market and financial, policy and institutional, scientific and technological and informational and behavioral barriers. More specifically, the shortage of woody biomass, strict regulation, considerable financial and time investment, and lack of experience and knowledge are hindering on-farm composting. The complex regulation, manure surplus, variable availability and transport of compost, and variable compost quality and composition are barriers to apply compost. In conclusion, five recommendations are suggested that could alleviate certain hindering factors and thus increase attractiveness of compost use in agriculture. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Shen, Yujun; Zhao, Lixin; Meng, Haibo; Hou, Yueqing; Zhou, Haibin; Wang, Fei; Cheng, Hongsheng; Liu, Hongbin
2016-06-01
Pollution by heavy metals, such as copper and lead, has become a limiting factor for the land application of faecal manures, such as pig manure. This study was conducted to investigate the influence of composting process parameters, including aeration rate, moisture content and composting period, on the distribution of heavy metal species during composting, and to select an optimal parameter for copper and lead inactivation. Results showed that the distribution ratios of exchangeable fractions of copper and lead had a bigger decrease under conditions of aeration rate, 0.1 m(3) min(-1) m(-3), an initial moisture content of 65% and composting period of 50 days. Suboptimal composting process conditions could lead to increased availability of heavy metals. Statistical analysis indicated that the aeration rate was the main factor affecting copper and lead inactivation, while the effects of moisture content and composting period were not significant. The rates of reduction of copper-exchangeable fractions and lead-exchangeable fractions were positively correlated with increased pH. The optimal parameters for reducing heavy metal bioavailability during pig manure composting were aeration rate, 0.1 m(3) min(-1) m(-3), initial moisture content, 65%, and composting period, 20 days. © The Author(s) 2016.
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Torres-Climent, A; Gomis, P; Martín-Mata, J; Bustamante, M A; Marhuenda-Egea, F C; Pérez-Murcia, M D; Pérez-Espinosa, A; Paredes, C; Moral, R
2015-01-01
The objective of this work was to study the co-composting process of wastes from the winery and distillery industry with animal manures, using the classical chemical methods traditionally used in composting studies together with advanced instrumental methods (thermal analysis, FT-IR and CPMAS 13C NMR techniques), to evaluate the development of the process and the quality of the end-products obtained. For this, three piles were elaborated by the turning composting system, using as raw materials winery-distillery wastes (grape marc and exhausted grape marc) and animal manures (cattle manure and poultry manure). The classical analytical methods showed a suitable development of the process in all the piles, but these techniques were ineffective to study the humification process during the composting of this type of materials. However, their combination with the advanced instrumental techniques clearly provided more information regarding the turnover of the organic matter pools during the composting process of these materials. Thermal analysis allowed to estimate the degradability of the remaining material and to assess qualitatively the rate of OM stabilization and recalcitrant C in the compost samples, based on the energy required to achieve the same mass losses. FT-IR spectra mainly showed variations between piles and time of sampling in the bands associated to complex organic compounds (mainly at 1420 and 1540 cm-1) and to nitrate and inorganic components (at 875 and 1384 cm-1, respectively), indicating composted material stability and maturity; while CPMAS 13C NMR provided semi-quantitatively partition of C compounds and structures during the process, being especially interesting their variation to evaluate the biotransformation of each C pool, especially in the comparison of recalcitrant C vs labile C pools, such as Alkyl /O-Alkyl ratio.
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Torres-Climent, A.; Gomis, P.; Martín-Mata, J.; Bustamante, M. A.; Marhuenda-Egea, F. C.; Pérez-Murcia, M. D.; Pérez-Espinosa, A.; Paredes, C.; Moral, R.
2015-01-01
The objective of this work was to study the co-composting process of wastes from the winery and distillery industry with animal manures, using the classical chemical methods traditionally used in composting studies together with advanced instrumental methods (thermal analysis, FT-IR and CPMAS 13C NMR techniques), to evaluate the development of the process and the quality of the end-products obtained. For this, three piles were elaborated by the turning composting system, using as raw materials winery-distillery wastes (grape marc and exhausted grape marc) and animal manures (cattle manure and poultry manure). The classical analytical methods showed a suitable development of the process in all the piles, but these techniques were ineffective to study the humification process during the composting of this type of materials. However, their combination with the advanced instrumental techniques clearly provided more information regarding the turnover of the organic matter pools during the composting process of these materials. Thermal analysis allowed to estimate the degradability of the remaining material and to assess qualitatively the rate of OM stabilization and recalcitrant C in the compost samples, based on the energy required to achieve the same mass losses. FT-IR spectra mainly showed variations between piles and time of sampling in the bands associated to complex organic compounds (mainly at 1420 and 1540 cm-1) and to nitrate and inorganic components (at 875 and 1384 cm-1, respectively), indicating composted material stability and maturity; while CPMAS 13C NMR provided semi-quantitatively partition of C compounds and structures during the process, being especially interesting their variation to evaluate the biotransformation of each C pool, especially in the comparison of recalcitrant C vs labile C pools, such as Alkyl /O-Alkyl ratio. PMID:26418458
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Experimental and modeling approaches for food waste composting: a review.
Li, Zhentong; Lu, Hongwei; Ren, Lixia; He, Li
2013-10-01
Composting has been used as a method to dispose food waste (FW) and recycle organic matter to improve soil structure and fertility. Considering the significance of composting in FW treatment, many researchers have paid their attention on how to improve FW composting efficiency, reduce operating cost, and mitigate the associated environmental damage. This review focuses on the overall studies of FW composting, not only various parameters significantly affecting the processes and final results, but also a number of simulation approaches that are greatly instrumental in well understanding the process mechanism and/or results prediction. Implications of many key ingredients on FW composting performance are also discussed. Perspects of effective laboratory experiments and computer-based simulation are finally investigated, demonstrating many demanding areas for enhanced research efforts, which include the screening of multi-functional additives, volatile organiccompound emission control, necessity of modeling and post-modeling analysis, and usefulness of developing more conjunctive AI-based process control techniques. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Coffee husk composting: an investigation of the process using molecular and non-molecular tools.
Shemekite, Fekadu; Gómez-Brandón, María; Franke-Whittle, Ingrid H; Praehauser, Barbara; Insam, Heribert; Assefa, Fassil
2014-03-01
Various parameters were measured during a 90-day composting process of coffee husk with cow dung (Pile 1), with fruit/vegetable wastes (Pile 2) and coffee husk alone (Pile 3). Samples were collected on days 0, 32 and 90 for chemical and microbiological analyses. C/N ratios of Piles 1 and 2 decreased significantly over the 90 days. The highest bacterial counts at the start of the process and highest actinobacterial counts at the end of the process (Piles 1 and 2) indicated microbial succession with concomitant production of compost relevant enzymes. Denaturing gradient gel electrophoresis of rDNA and COMPOCHIP microarray analysis indicated distinctive community shifts during the composting process, with day 0 samples clustering separately from the 32 and 90-day samples. This study, using a multi-parameter approach, has revealed differences in quality and species diversity of the three composts. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Catalán, Eva; Komilis, Dimitrios; Sánchez, Antoni
2017-07-01
One of the wastes associated with leather production in tannery industries is the hair residue generated during the dehairing process. Hair wastes are mainly dumped or managed through composting but recent studies propose the treatment of hair wastes through solid-state fermentation (SSF) to obtain proteases and compost. These enzymes are suitable for its use in an enzymatic dehairing process, as an alternative to the current chemical dehairing process. In the present work, two different scenarios for the valorization of the hair waste are proposed and assessed by means of life-cycle assessment: composting and SSF for protease production. Detailed data on hair waste composting and on SSF protease production are gathered from previous studies performed by our research group and from a literature survey. Background inventory data are mainly based on Ecoinvent version 3 from software SimaPro® 8. The main aim of this study was to identify which process results in the highest environmental impact. The SSF process was found to have lower environmental impacts than composting, due to the fact that the enzyme use in the dehairing process prevents the use of chemicals traditionally used in the dehairing process. This permits to reformulate an industrial process from the classical approach of waste management to a novel alternative based on circular economy.
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Faverial, Julie; Cornet, Denis; Paul, Jacky
2016-01-01
Previous studies indicated that the quality of tropical composts is poorer than that of composts produced in temperate regions. The aim of this study was to test the type of manure, the use of co-composting with green waste, and the stabilization method for their ability to improve compost quality in the tropics. We produced 68 composts and vermicomposts that were analysed for their C, lignin and NPK contents throughout the composting process. Bayesian networks were used to assess the mechanisms controlling compost quality. The concentration effect, for C and lignin, and the initial blend quality, for NPK content, were the main factors affecting compost quality. Cattle manure composts presented the highest C and lignin contents, and poultry litter composts exhibited the highest NPK content. Co-composting improved quality by enhancing the concentration effect, which reduced the impact of C and nutrient losses. Vermicomposting did not improve compost quality; co-composting without earthworms thus appears to be a suitable stabilization method under the conditions of this study because it produced high quality composts and is easier to implement. PMID:27314950
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Tkachuk, Victoria L; Krause, Denis O; McAllister, Tim A; Buckley, Katherine E; Reuter, Tim; Hendrick, Steve; Ominski, Kim H
2013-05-01
Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle mortalities.
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Tkachuk, Victoria L.; Krause, Denis O.; McAllister, Tim A.; Buckley, Katherine E.; Reuter, Tim; Hendrick, Steve
2013-01-01
Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle mortalities. PMID:23503307
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Smith, Stephen R
2009-01-01
The content, behaviour and significance of heavy metals in composted waste materials is important from two potentially conflicting aspects of environmental legislation in terms of: (a) defining end-of-waste criteria and increasing recycling of composted residuals on land and (b) protecting soil quality by preventing contamination. This review examines the effects of heavy metals in compost and amended soil as a basis for achieving a practical and sustainable balance between these different policy objectives, with particular emphasis on agricultural application. All types of municipal solid waste (MSW) compost contain more heavy metals than the background concentrations present in soil and will increase their contents in amended soil. Total concentrations of heavy metals in source-segregated and greenwaste compost are typically below UK PAS100 limits and mechanical segregated material can also comply with the metal limits in UK PAS100, although this is likely to be more challenging. Zinc and Pb are numerically the elements present in the largest amounts in MSW-compost. Lead is the most limiting element to use of mechanically-segregated compost in domestic gardens, but concentrations are typically below risk-based thresholds that protect human health. Composted residuals derived from MSW and greenwaste have a high affinity for binding heavy metals. There is general consensus in the scientific literature that aerobic composting processes increase the complexation of heavy metals in organic waste residuals, and that metals are strongly bound to the compost matrix and organic matter, limiting their solubility and potential bioavailability in soil. Lead is the most strongly bound element and Ni the weakest, with Zn, Cu and Cd showing intermediate sorption characteristics. The strong metal sorption properties of compost produced from MSW or sewage sludge have important benefits for the remediation of metal contaminated industrial and urban soils. Compost and sewage sludge additions to agricultural and other soils, with background concentrations of heavy metals, raise the soil content and the availability of heavy metals for transfer into crop plants. The availability in soil depends on the nature of the chemical association between a metal with the organic residual and soil matrix, the pH value of the soil, the concentration of the element in the compost and the soil, and the ability of the plant to regulate the uptake of a particular element. There is no evidence of increased metal release into available forms as organic matter degrades in soil once compost applications have ceased. However, there is good experimental evidence demonstrating the reduced bioavailability and crop uptake of metals from composted biosolids compared to other types of sewage sludge. It may therefore be inferred that composting processes overall are likely to contribute to lowering the availability of metals in amended soil compared to other waste biostabilisation techniques. The total metal concentration in compost is important in controlling crop uptake of labile elements, like Zn and Cu, which increases with increasing total content of these elements in compost. Therefore, low metal materials, which include source-segregated and greenwaste composts, are likely to have inherently lower metal availabilities overall, at equivalent metal loading rates to soil, compared to composted residuals with larger metal contents. This is explained because the compost matrix modulates metal availability and materials low in metals have stronger sorption capacity compared to high metal composts. Zinc is the element in sewage sludge-treated agricultural soil identified as the main concern in relation to potential impacts on soil microbial activity and is also the most significant metal in compost with regard to soil fertility and microbial processes. However, with the exception of one study, there is no other tangible evidence demonstrating negative impacts of heavy metals applied to soil in compost on soil microbial processes and only positive effects of compost application on the microbial status and fertility of soil are reported. The negative impacts on soil microorganisms apparent in one long-term field experiment could be explained by the exceptionally high concentrations of Cd and other elements in the applied compost, and of Cd in the compost-amended soil, which are unrepresentative of current practice and compost quality. The metal contents of source-segregated MSW or greenwaste compost are smaller compared to mechanically-sorted MSW-compost and sewage sludge, and low metal materials also have the smallest potential metal availabilities. Composting processes also inherently reduce metal availability compared to other organic waste stabilisation methods. Therefore, risks to the environment, human health, crop quality and yield, and soil fertility, from heavy metals in source-segregated MSW or greenwaste-compost are minimal. Furthermore, composts produced from mechanically-segregated MSW generally contain fewer metals than sewage sludge used as an agricultural soil improver under controlled conditions. Consequently, the metal content of mechanically-segregated MSW-compost does not represent a barrier to end-use of the product. The application of appropriate preprocessing and refinement technologies is recommended to minimise the contamination of mechanically-segregated MSW-compost as far as practicable. In conclusion, the scientific evidence indicates that conservative, but pragmatic limits on heavy metals in compost may be set to encourage recycling of composted residuals and contaminant reduction measures, which at the same time, also protect the soil and environment from potentially negative impacts caused by long-term accumulation of heavy metals in soil.
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Respirometric screening of several types of manure and mixtures intended for composting.
Barrena, Raquel; Turet, Josep; Busquets, Anna; Farrés, Moisès; Font, Xavier; Sánchez, Antoni
2011-01-01
The viability of mixtures from manure and agricultural wastes as composting sources were systematically studied using a physicochemical and biological characterization. The combination of different parameters such as C:N ratio, free air space (FAS) and moisture content can help in the formulation of the mixtures. Nevertheless, the composting process may be challenging, particularly at industrial scales. The results of this study suggest that if the respirometric potential is known, it is possible to predict the behaviour of a full scale composting process. Respiration indices can be used as a tool for determining the suitability of composting as applied to manure and complementary wastes. Accordingly, manure and agricultural wastes with a high potential for composting and some proposed mixtures have been characterized in terms of respiration activity. Specifically, the potential of samples to be composted has been determined by means of the oxygen uptake rate (OUR) and the dynamic respirometric index (DRI). During this study, four of these mixtures were composted at full scale in a system consisting of a confined pile with forced aeration. The biological activity was monitored by means of the oxygen uptake rate inside the material (OURinsitu). This new parameter represents the real activity of the process. The comparison between the potential respirometric activities at laboratory scale with the in situ respirometric activity observed at full scale may be a useful tool in the design and optimization of composting systems for manure and other organic agricultural wastes. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Kertesz, Michael A; Thai, Meghann
2018-02-01
Mushrooms are an important food crop for many millions of people worldwide. The most important edible mushroom is the button mushroom (Agaricus bisporus), an excellent example of sustainable food production which is cultivated on a selective compost produced from recycled agricultural waste products. A diverse population of bacteria and fungi are involved throughout the production of Agaricus. A range of successional taxa convert the wheat straw into compost in the thermophilic composting process. These initially break down readily accessible compounds and release ammonia, and then assimilate cellulose and hemicellulose into compost microbial biomass that forms the primary source of nutrition for the Agaricus mycelium. This key process in composting is performed by a microbial consortium consisting of the thermophilic fungus Mycothermus thermophilus (Scytalidium thermophilum) and a range of thermophilic proteobacteria and actinobacteria, many of which have only recently been identified. Certain bacterial taxa have been shown to promote elongation of the Agaricus hyphae, and bacterial activity is required to induce production of the mushroom fruiting bodies during cropping. Attempts to isolate mushroom growth-promoting bacteria for commercial mushroom production have not yet been successful. Compost bacteria and fungi also cause economically important losses in the cropping process, causing a range of destructive diseases of mushroom hyphae and fruiting bodies. Recent advances in our understanding of the key bacteria and fungi in mushroom compost provide the potential to improve productivity of mushroom compost and to reduce the impact of crop disease.
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Microbial diversity in a bagasse-based compost prepared for the production of Agaricus brasiliensis
Silva, Cristina Ferreira; Azevedo, Raquel Santos; Braga, Claudia; da Silva, Romildo; Dias, Eustáquio Souza; Schwan, Rosane Freitas
2009-01-01
Edible mushrooms are renowned for their nutritional and medicinal properties and are thus of considerable commercial importance. Mushroom production depends on the chemical composition of the basic substrates and additional supplements employed in the compost as well as on the method of composting. In order to minimise the cost of mushroom production, considerable interest has been shown in the use of agro-industrial residues in the preparation of alternative compost mixtures. However, the interaction of the natural microbiota present in agricultural residues during the composting process greatly influences the subsequent colonisation by the mushroom. The aim of the present study was to isolate and identify the microbiota present in a sugar cane bagasse and coast-cross straw compost prepared for the production of Agaricus brasilienses. Composting lasted for 14 days, during which time the substrates and additives were mixed every 2 days, and this was followed by a two-step steam pasteurisation (55 - 65°C; 15 h each step). Bacteria, (mainly Bacillus and Paenibacillus spp. and members of the Enterobacteriaceae) were the predominant micro-organisms present throughout the composting process with an average population density of 3 x 108 CFU/g. Actinomycetes, and especially members of the genus Streptomyces, were well represented with a population density of 2 - 3 x 108 CFU/g. The filamentous fungi, however, exhibited much lower population densities and were less diverse than the other micro-organisms, although Aspergillus fumigatus was present during the whole composting process and after pasteurisation. PMID:24031404
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Influence of N-rich material in valorization of industrial eggshell by co-composting.
Soares, Micaela A R; Quina, Margarida J; Quinta-Ferreira, Rosa
2016-11-01
Industrial eggshell (ES) is an animal by-product (ABP) involving some risk if not properly managed. Composting is a possible treatment approved for its safe use. This study aims to assess the influence of using N-rich material (grass clippings (GC)) to improve co-composting of ES mixtures for reaching sanitizing temperatures imposed by the ABP regulation from the European Union. Two sets of mixtures (M1 and M2) were investigated, each containing industrial potato peel waste, GC and rice husks at 3:1.9:1 and 3:0:1 ratios by wet weight. In each set, ES composition ranged from 0% to 30% (w/w). Co-composting trials were performed in self-heating reactors for 25 days, followed by maturation in piles. Results showed that only M1 trials attained temperatures higher than 70°C for nine consecutive hours, but N-losses by stripping on average were four- to five-fold higher than M2. In the absence of N-rich material, biodegradability of mixtures was 'low' to 'moderate' and organic matter conversion was impaired. Physical, chemical and phytotoxic properties of finished composts were suitable for soil improvement, but M1 took 54 more days to achieve maturity. In conclusion, co-composting ES with N-rich materials is important to assure the fulfilment of sanitizing requirements, avoiding any additional thermal treatment.
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Gabhane, Jagdish; William, S P M Prince; Bidyadhar, Rajnikant; Bhilawe, Priya; Anand, Duraisamy; Vaidya, Atul N; Wate, Satish R
2012-06-01
The effect of various additives such as fly ash, phosphogypsum, jaggery, lime, and polyethylene glycol on green waste composting was investigated through assessing their influence on microbial growth, enzymatic activities, organic matter degradation, bulk density, quality of finished compost including gradation test, heavy metal analysis, etc. A perusal of results showed that addition of jaggery and polyethylene glycol were helpful to facilitate composting process as they significantly influenced the growth of microbes and cellulase activity. The quality of finished compost prepared from jaggery and polyethylene glycol added treatments were superior to other composts, wherein reduction in C/N ratio was more than 8% in jaggery treatment. All other parameters of compost quality including gradation test also favored jaggery and polyethylene glycol as the best additives for green waste composting. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Xu, Piao; Lai, Cui; Zeng, Guangming; Huang, Danlian; Chen, Ming; Song, Biao; Peng, Xin; Wan, Jia; Hu, Liang; Duan, Abing; Tang, Wangwang
2018-02-01
Composting is identified as an effective approach for solid waste disposal. The bioremediation of 4-nonylphenol (4NP) and cadmium (Cd) co-contaminated sediment was investigated by composting with Phanerochaete chrysosporium (P. chrysosporium) inocula. P. chrysosporium inocula and proper C/N ratios (25.51) accelerated the composting process accompanied with faster total organic carbon loss, 4NP degradation and Cd passivation. Microbiological analysis demonstrated that elevated activities of lignocellulolytic enzymes and sediment enzymes was conducive to organic chemical transformation. Bacterial community diversity results illustrated that Firmicutes and Proteobacteria were predominant species during the whole composting process. Aerobic cellulolytic bacteria and organic degrading species played significant roles. Toxicity characteristic leaching procedure (TCLP) extraction and germination indices results indicated the efficient detoxification of 4NP and Cd co-contaminated sediment after 120 days of composting. Overall, results demonstrated that P. chrysosporium enhanced composting was available for the bioremediation of 4NP and Cd co-contaminated sediment. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Physicochemical profile of microbial-assisted composting on empty fruit bunches of oil palm trees.
Lim, Li Yee; Bong, Cassendra Phun Chien; Chua, Lee Suan; Lee, Chew Tin
2015-12-01
This study was carried out to investigate the physicochemical properties of compost from oil palm empty fruit bunches (EFB) inoculated with effective microorganisms (EM∙1™). The duration of microbial-assisted composting was shorter (∼7 days) than control samples (2 months) in a laboratory scale (2 kg) experiment. The temperature profile of EFB compost fluctuated between 26 and 52 °C without the presence of consistent thermophilic phase. The pH of compost changed from weak acidic (pH ∼5) to mild alkaline (pH ∼8) because of the formation of nitrogenous ions such as ammonium (NH4 (+)), nitrite (NO2 (-)), and nitrate (NO3 (-)) from organic substances during mineralization. The pH of the microbial-treated compost was less than 8.5 which is important to prevent the loss of nitrogen as ammonia gas in a strong alkaline condition. Similarly, carbon mineralization could be determined by measuring CO2 emission. The microbial-treated compost could maintain longer period (∼13 days) of high CO2 emission resulted from high microbial activity and reached the threshold value (120 mg CO2-C kg(-1) day(-1)) for compost maturity earlier (7 days). Microbial-treated compost slightly improved the content of minerals such as Mg, K, Ca, and B, as well as key metabolite, 5-aminolevulinic acid for plant growth at the maturity stage of compost. Graphical Abstract Microbial-assisted composting on empty fruit bunches.
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High rate composting of herbal pharmaceutical industry solid waste.
Ali, M; Duba, K S; Kalamdhad, A S; Bhatia, A; Khursheed, A; Kazmi, A A; Ahmed, N
2012-01-01
High rate composting studies of hard to degrade herbal wastes were conducted in a 3.5 m(3) capacity rotary drum composter. Studies were spread out in four trials: In trial 1 and 2, one and two turns per day rotation was observed, respectively, by mixing of herbal industry waste with cattle (buffalo) manure at a ratio of 3:1 on wet weight basis. In trial 3 inocula was added in raw waste to enhance the degradation and in trial 4 composting of a mixture of vegetable market waste and herbal waste was conducted at one turn per day. Results demonstrated that the operation of the rotary drum at one turn a day (trial 1) could provide the most conducive composting conditions and co-composting (trial 4) gave better quality compost in terms of temperature, moisture, nitrogen, and Solvita maturity index. In addition a FT-IR study also revealed that trial 1 and trial 4 gave quality compost in terms of stability and maturity due to the presence of more intense peaks in the aromatic region and less intense peaks were found in the aliphatic region compared with trial 2 and trial 3.
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Effects of earthworm casts and zeolite on the two-stage composting of green waste.
Zhang, Lu; Sun, Xiangyang
2015-05-01
Because it helps protect the environment and encourages economic development, composting has become a viable method for organic waste disposal. The objective of this study was to investigate the effects of earthworm casts (EWCs) (at 0.0%, 0.30%, and 0.60%) and zeolite (clinoptilolite, CL) (at 0%, 15%, and 25%) on the two-stage composting of green waste. The combination of EWCs and CL improved the conditions of the composting process and the quality of the compost products in terms of the thermophilic phase, humification, nitrification, microbial numbers and enzyme activities, the degradation of cellulose and hemicellulose, and physico-chemical characteristics and nutrient contents of final composts. The compost matured in only 21days with the optimized two-stage composting method rather than in the 90-270days required for traditional composting. The optimal two-stage composting and the best quality compost were obtained with 0.30% EWCs and 25% CL. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Physico-chemical and biological characteristics of compost from decentralised composting programmes.
Vázquez, M A; Sen, R; Soto, M
2015-12-01
Composts that originated from small-scale composting programmes including home, community and canteen waste composters were studied. Heavy metals concentration indicated compliance with current regulations for conventional and organic agriculture. Compost from canteen waste showed high organic matter content (74% VS), while community (44 ± 20% VS) and home composts (31 ± 16% VS) had moderate levels. N content increased from home compost (1.3 ± 0.9% dm) to community (2.0 ± 0.9%) and canteen compost (2.5-3.0%) while P content ranged from 0.4% to 0.6% dm. C/N, absorbance E4/E6 and N-NH4(+)/N-NO3(-) ratios as well as respiration index indicated well-stabilized final products. Culturable bacterial and fungal cfu linkage to composting dynamics were identified and higher diversity of invertebrates was found in the smaller scale static systems. With similar process evolution indicators to industrial systems, overall results support the sustainability of these small-scale, self-managed composting systems. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Conza, Lisa; Pagani, Simona Casati; Gaia, Valeria
2013-01-01
Several species of Legionella cause Legionnaires’ disease (LD). Infection may occur through inhalation of Legionella or amoebal vesicles. The reservoirs of Legionella are water, soil, potting soil and compost. Some species of free-living amoebae (FLA) that are naturally present in water and soil were described as hosts for Legionella. This study aimed to understand whether or not the composting facilities could be sources of community-acquired Legionella infections after development of bioaerosols containing Legionella or FLA. We looked for the presence of Legionella (by co-culture) and FLA (by culture) in composts and bioaerosols collected at four composting facilities located in southern Switzerland. We investigated the association between the presence of Legionella and compost and air parameters and presence of FLA. Legionella spp. (including L. pneumophila) were detected in 69.3% (61/88) of the composts and FLA (mainly Acanthamoeba, Vermamoeba, Naegleria and Stenamoeba) in 92.0% (81/88). L. pneumophila and L. bozemanii were most frequently isolated. FLA as potential host for Legionella spp. were isolated from 40.9% (36/88) of the composts in all facilities. In Legionella-positive samples the temperature of compost was significantly lower (P = 0.012) than in Legionella-negative samples. Of 47 bioaerosol samples, 19.1% (9/47) were positive for FLA and 10.6% (5/47) for L. pneumophila. Composts (62.8%) were positive for Legionella and FLA contemporaneously, but both microorganisms were never detected simultaneously in bioaerosols. Compost can release bioaerosol containing FLA or Legionella and could represent a source of infection of community-acquired Legionella infections for workers and nearby residents. PMID:23844174
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Nakasaki, Kiyohiko; Ohtaki, Akihito; Takemoto, Minoru; Fujiwara, Shunrokuro
2011-03-01
The effect of various operational conditions on the decomposition of organic material during the composting of night-soil treatment sludge was quantitatively examined. The optimum composting conditions were found to be a temperature of ca. 60°C and an initial pH value of 8. Rapid decomposition of organic matter ceased by the sixth day of composting under these optimum conditions, and the final value of the cumulative emission of carbon (E(C)), which represents the degree of organic matter decomposition, was less than 40%, indicating that the sludge contained only a small amount of easily degradable organic material. A plant growth assay using Komatsuna (Brassica campestris L. var. rapiferafroug) in a 1/5000a standard cultivation pot was then conducted for the compost at various degrees of organic matter decomposition: the raw composting material, the final compost obtained on day 6, and the 2 intermediate compost products (i.e., E(C)=10% and 20%). It was found that the larger the E(C), the greater the yield of Komatsuna growth. It was also found that 6 days of composting is sufficient to promote Komatsuna growth at the standard loading level, which is equivalent to a 1.5 g N/pot, since the promotion effect was as high as that obtained using chemical fertilizer. It can therefore be concluded that well-matured compost could be obtained in a short period of time (i.e., as early as 6 days), when night-soil sludge is composted under optimum conditions. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Speciation of Cu and Zn during composting of pig manure amended with rock phosphate.
Lu, Duian; Wang, Lixia; Yan, Baixing; Ou, Yang; Guan, Jiunian; Bian, Yu; Zhang, Yubin
2014-08-01
Pig manure usually contains a large amount of metals, especially Cu and Zn, which may limit its land application. Rock phosphate has been shown to be effective for immobilizing toxic metals in toxic metals contaminated soils. The aim of this study work was to investigate the effect of rock phosphate on the speciation of Cu and Zn during co-composting of pig manure with rice straw. The results showed that composting process and rock phosphate addition significantly affected the changes of metal species. During co-composting, the exchangeable and reducible fractions of Cu were transformed to organic and residue fractions, thus the bioavailable Cu fractions were decreased. The rock phosphate addition enhanced the metal transformation depending on the level of rock phosphate amendment. Zinc was found in the exchangeable and reducible fractions in the compost. The bioavailable Zn fraction changed a little during the composting process. The composting process converted the exchangeable Zn fraction into reducible fraction. Addition of an appropriate amount (5.0%) of rock phosphate could advance the conversion. Rock phosphate could reduce metal availability through adsorption and complexation of the metal ions on inorganic components. The increase in pH and organic matter degradation could be responsible for the reduction in exchangeable and bioavailable Cu fractions and exchangeable Zn fraction in rock phosphate amended compost. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Compost biodegradation of recalcitrant hoof keratin by bacteria and fungi.
Reuter, T; Gilroyed, B H; Xu, W; McAllister, T A; Stanford, K
2015-08-01
Compost activities efficiently break down a wide range of organic substances over time. In this study, bovine hoof was used as recalcitrant protein model to gain so far cryptic information on biodegradation during livestock mortalities composting. Bovine hooves (black and white), containing different amounts of melanin, placed into nylon bags were monitored during composting of cattle mortalities for up to 230 days. Besides physiochemical analysis, bacterial 16S and fungal 18S DNA fragments were amplified by PCR and profiles were separated by DGGE. Sequence analysis of separated fragments revealed various bacterial and fungal identities during composting. The microbial diversity was affected by a time-temperature interaction and by the hoof colour. Our molecular data, supported by electron microscopy, suggest hoof colonization by shifting bacteria and fungi communities. During composting, microbial communities work collaboratively in the degradation of recalcitrant organic matter such as keratin over time. A number of biomolecules including recalcitrant proteins may persist in environmental reservoirs, but breakdown can occur during composting. A combination of bioactivity and physiochemical conditions appear to be decisive for the fate of persistent biomolecules. © 2015 The Society for Applied Microbiology.
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Mbareche, Hamza; Veillette, Marc; Bonifait, Laetitia; Dubuis, Marie-Eve; Benard, Yves; Marchand, Geneviève; Bilodeau, Guillaume J; Duchaine, Caroline
2017-12-01
Composting is used all over the world to transform different types of organic matter through the actions of complex microbial communities. Moving and handling composting material may lead to the emission of high concentrations of bioaerosols. High exposure levels are associated with adverse health effects among compost industry workers. Fungal spores are suspected to play a role in many respiratory illnesses. There is a paucity of information related to the detailed fungal diversity in compost as well as in the aerosols emitted through composting activities. The aim of this study was to analyze the fungal diversity of both organic matter and aerosols present in facilities that process domestic compost and facilities that process pig carcasses. This was accomplished using a next generation sequencing approach that targets the ITS1 genomic region. Multivariate analyses revealed differences in the fungal community present in samples coming from compost treating both raw materials. Furthermore, results show that the compost type affects the fungal diversity of aerosols emitted. Although 8 classes were evenly distributed in all samples, Eurotiomycetes were more dominant in carcass compost while Sordariomycetes were dominant in domestic compost. A large diversity profile was observed in bioaerosols from both compost types showing the presence of a number of pathogenic fungi newly identified in bioaerosols emitted from composting plants. Members of the family Herpotrichiellaceae and Gymnoascaceae which have been shown to cause human diseases were detected in compost and air samples. Moreover, some fungi were identified in higher proportion in air compared to compost. This is the first study to identify a high level of fungal diversity in bioaerosols present in composting plants suggesting a potential exposure risk for workers. This study suggests the need for creating guidelines that address human exposure to bioaerosols. The implementation of technical and organizational measure should be a top priority. However, skin and respiratory protection for compost workers could be used to reduce the exposure as a second resort. Copyright © 2017 Elsevier B.V. All rights reserved.
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Effects of pH and microbial composition on odour in food waste composting
Sundberg, Cecilia; Yu, Dan; Franke-Whittle, Ingrid; Kauppi, Sari; Smårs, Sven; Insam, Heribert; Romantschuk, Martin; Jönsson, Håkan
2013-01-01
A major problem for composting plants is odour emission. Slow decomposition during prolonged low-pH conditions is a frequent process problem in food waste composting. The aim was to investigate correlations between low pH, odour and microbial composition during food waste composting. Samples from laboratory composting experiments and two large scale composting plants were analysed for odour by olfactometry, as well as physico-chemical and microbial composition. There was large variation in odour, and samples clustered in two groups, one with low odour and high pH (above 6.5), the other with high odour and low pH (below 6.0). The low-odour samples were significantly drier, had lower nitrate and TVOC concentrations and no detectable organic acids. Samples of both groups were dominated by Bacillales or Actinobacteria, organisms which are often indicative of well-functioning composting processes, but the high-odour group DNA sequences were similar to those of anaerobic or facultatively anaerobic species, not to typical thermophilic composting species. High-odour samples also contained Lactobacteria and Clostridia, known to produce odorous substances. A proposed odour reduction strategy is to rapidly overcome the low pH phase, through high initial aeration rates and the use of additives such as recycled compost. PMID:23122203
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HEAVY METAL ASPECTS OF COMPOST USE
Composts prepared from municipal solid waste, biosolids, food processing wastes, manures, yard debris, and agricultural byproducts and residues are increasingly available for agricultural use. Although many benefits are possible from use of composts, these products must be safe f...
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Liu, Dongming; Li, Mingxiao; Xi, Beidou; Zhao, Yue; Wei, Zimin; Song, Caihong; Zhu, Chaowei
2015-01-01
Composting is an appropriate management alternative for municipal solid waste; however, our knowledge about the microbial regulation of this process is still scare. We employed metaproteomics to elucidate the main biodegradation pathways in municipal solid waste composting system across the main phases in a large-scale composting plant. The investigation of microbial succession revealed that Bacillales, Actinobacteria and Saccharomyces increased significantly with respect to abundance in composting process. The key microbiologic population for cellulose degradation in different composting stages was different. Fungi were found to be the main producers of cellulase in earlier phase. However, the cellulolytic fungal communities were gradually replaced by a purely bacterial one in active phase, which did not support the concept that the thermophilic fungi are active through the thermophilic phase. The effective decomposition of cellulose required the synergy between bacteria and fungi in the curing phase. PMID:25989417
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Using cow dung and spent coffee grounds to enhance the two-stage co-composting of green waste.
Zhang, Lu; Sun, Xiangyang
2017-12-01
The objective of this study was to determine the effects of cow dung (CD) (at 0%, 20%, and 35%) and/or spent coffee grounds (SCGs) (at 0%, 30%, and 45%) as amendments in the two-stage co-composting of green waste (GW); the percentages refer to grams of amendment per 100g of GW based on dry weights. The combined addition of CD and SCGs improved the conditions during co-composting and the quality of the compost product in terms of composting temperature; particle-size distribution; mechanical properties; nitrogen changes; low-molecular weight compounds; humic substances; the degradation of lignin, cellulose, and hemicellulose; enzyme activities; the contents of total Kjeldahl nitrogen, total phosphorus, and total potassium; and the toxicity to germinating seeds. The combined addition of 20% CD and 45% SCGs to GW resulted in the production of the highest quality compost product and did so in only 21days. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Hanajima, Dai; Kuroda, Kazutaka; Fukumoto, Yasuyuki; Haga, Kiyonori
2006-09-01
To ensure Escherichia coli reduction during cattle feces composting, co-composting with a variety of organic wastes was examined. A mixture of dairy cattle feces and shredded rice straw (control) was blended with organic wastes (tofu residue, rice bran, rapeseed meal, dried chicken feces, raw chicken feces, or garbage), and composted using a bench-scale composter under the high-moisture condition (78%). The addition of organic waste except chicken feces brought about maximum temperatures of more than 55 degrees C and significantly reduced the number of E. coli from 10(6) to below 10(2)CFU/g-wet after seven days composting, while in the control treatment, E. coli survived at the same level as that of raw feces. Enhancements of the thermophilic phase and E. coli reduction were related to the initial amount of easily digestible carbon in mass determined as BOD. BOD value more than 166.2 mg O2/DMg brought about significant E. coli reduction.
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Evolution of organic matter during the mesophilic composting of lignocellulosic winery wastes.
Paradelo, Remigio; Moldes, Ana Belén; Barral, María Teresa
2013-02-15
Winery wastes were composted in the laboratory during five months in order to study the composting process of lignocellulosic wastes. In a first experiment, spent grape marc was composted alone, and in a second one, hydrolyzed grape marc, which is the residue generated after the acid hydrolysis of spent grape marc for biotechnological purposes, was composted together with vinification lees. During the composting of spent grape marc, total organic matter did not change, and as total N increased only slightly (from 1.7% to 1.9%), the reduction in the C/N ratio was very low (from 31 to 28). The mixture of hydrolyzed grape marc and lees showed bigger changes, reaching a C/N ratio around 20 from the third month on. Water-soluble organic matter followed the usual trend during composting, showing a progressive decrease in both experiments. Although the mixture of hydrolyzed grape marc and lees presented the highest initial water-soluble carbon concentrations, the final values for both experiments were similar (8.1 g kg(-1) for the spent grape marc, and 9.1 g kg(-1) for the mixture). The analysis of the humification parameters did not allow an adequate description of the composting process, maybe as a consequence of the inherent problems existing with alkaline extractions. The total humic substances, which usually increase during composting as a consequence of the humification process, followed no trend, and they were even reduced with respect to the initial values. Notwithstanding, the fractionation of organic matter into cellulose, hemicellulose and lignin enabled a better monitoring of the waste decomposition. Cellulose and hemicellulose were degraded mainly during the first three months of composting, and the progressive reduction of the cellulose/lignin ratio proved that the main evolution of these wastes took place during the first three months of composting. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Pathogen analysis of NYSDOT road-killed deer carcass compost facilities.
DOT National Transportation Integrated Search
2008-09-01
Composting of deer carcasses was effective in reducing pathogen levels, decomposing the : carcasses and producing a useable end product after 12 months. The composting process used in this project : involved enveloping the carcasses of road-killed de...
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Unmar, G; Mohee, R
2008-10-01
An assessment of the effect of the composting potential of Mater-Bi biodegradable plastic with green wastes, noted by GBIO, and degradable plastic (PDQ-H additive) with green wastes, noted by GDEG, was carried out in a lagged two-compartment compost reactor. The composting time was determined until constant mass of the composting substrates was reached. The green wastes composting process was used as control (G). After one week of composting, the biodegradable plastics disappeared completely, while 2% of the original degradable plastic still remained after about 8 weeks of composting. A net reduction in volatile solids contents of 61.8%, 56.5% and 53.2% were obtained for G, GBIO and GDEG, respectively. Compost quality was assessed in terms of nitrogen, potassium and phosphorus contents, which were found to be highest for GBIO compost. From the phytotoxicity test, it has been observed that a diluted extract of GBIO compost has produced the longest length of radicle. From the respiration test, no significant difference in the amount of carbon dioxide released by the composting of GDEG and G was observed. This study showed that the quality of the compost is not affected by the presence of the biodegradable and degradable plastics in the raw materials.
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Dissipation of 17B-estradiol in composted poultry litter
USDA-ARS?s Scientific Manuscript database
The effects of heated composting and ambient temperature poultry waste decomposition on the fate of 17ß-estradiol and testosterone were determined in separate experiments. A mixture of poultry litter, wood chips and straw was amended with [14C]17ß-estradiol or [14C]testosterone and allowed to under...
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Effect of moisture content on the heating profile in composted broiler litter
USDA-ARS?s Scientific Manuscript database
Moisture content can affect the magnitude of heat generation during composting. Temperature was recorded every 2 min for 7 d at 10-cm increments throughout the vertical profile of broiler litter treated with five quantities of water addition. Water additions were applied to achieve litter moisture...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Tambone, Fulvia, E-mail: fulvia.tambone@unimi.it; Terruzzi, Laura; Scaglia, Barbara
Highlights: • Anaerobic digestion leads to the production of a biologically stable digestate. • Solid–liquid separation produces a solid fraction having high fertilizer value. • Composting process shows low biological activity due to high biological stability of digestate. • Solid digestate fraction can be composted in a short time or used directly as organic fertilizer. - Abstract: The aim of this paper was to assess the characteristics of the solid fractions (SF) obtained by mechanical separation of digestate, their compostability and compost quality. To do so, the SF of digestates obtained from anaerobic digestion of pig slurry, energy crops andmore » agro-industrial residues were sampled in five plants located in Northern Italy. Results obtained indicated that anaerobic digestion by itself promoted the high biological stability of biomasses with a Potential Dynamic Respiration Index (PDRI) close to 1000 mgO{sub 2} kg V S{sup −1} h{sup −1}. Subsequent composting of digestates, with an added bulking agent, did not give remarkably different results, and led only to a slight modification of the characteristics of the initial non-composted mixtures; the composts obtained fully respected the legal limits for high quality compost. Chemical studies of organic matter composition of the biomasses by using CP MAS {sup 13}C NMR, indicated that the compost was composed of a high relative content of O-alkyl-C (71.47% of total C) (cellulose and hemicelluloses) and a low alkyl-C (12.42%) (i.e. volatile fatty acids, steroid-like molecules, aliphatic biopolymers and proteins)« less
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Novel multifunctional plant growth-promoting bacteria in co-compost of palm oil industry waste.
Chin, Clament Fui Seung; Furuya, Yoshihide; Zainudin, Mohd Huzairi Mohd; Ramli, Norhayati; Hassan, Mohd Ali; Tashiro, Yukihiro; Sakai, Kenji
2017-11-01
Previously, a unique co-compost produced by composting empty fruit bunch with anaerobic sludge from palm oil mill effluent, which contributed to establishing a zero-emission industry in Malaysia. Little was known about the bacterial functions during the composting process and fertilization capacity of this co-compost. We isolated 100 strains from the co-compost on 7 types of enumeration media and screened 25 strains using in vitro tests for 12 traits, grouping them according to three functions: plant growth promoting (fixation of nitrogen; solubilization of phosphorus, potassium, and silicate; production of 3-indoleacetic acid, ammonia, and siderophore), biocontrolling (production of chitinase and anti-Ganoderma activity), and composting (degradation of lignin, xylan, and cellulose). Using 16S rRNA gene sequence analysis, 25 strains with strong or multi-functional traits were found belong to the genera Bacillus, Paenibacillus, Citrobacter, Enterobacter, and Kosakonia. Furthermore, several strains of Citrobacter sedlakii exhibited a plant growth-stimulation in vivo komatsuna plant cultivation test. In addition, we isolated several multifunctional strains; Bacillus tequilensis CE4 (biocontrolling and composting), Enterobacter cloacae subsp. dissolvens B3 (plant growth promoting and biocontrolling), and C. sedlakii CESi7 (plant growth promoting and composting). Some bacteria in the co-compost play significant roles during the composting process and plant cultivation after fertilization, and some multifunctional strains have potential for use in accelerating the biodegradation of lignocellulosic biomass, protecting against Ganoderma boninense infection, and increasing the yield of palm oil. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
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Decrease in water-soluble 17beta-Estradiol and testosterone in composted poultry manure with time.
Hakk, Heldur; Millner, Patricia; Larsen, Gerald
2005-01-01
Little attention has been paid to the environmental fate of the hormones 17beta-estradiol and testosterone excreted in animal waste. Land application of manure has a considerable potential to affect the environment with these endocrine disrupting compounds (EDCs). Composting is known to decompose organic matter to a stable, humus-like material. The goal of the present study was to quantitatively assess levels of water-soluble 17beta-estradiol and testosterone in composting chicken manure with time. Chicken layer manure was mixed with hay, straw, decomposed leaves, and starter compost, adjusted to approximately 60% moisture, and placed into a windrow. A clay-amended windrow was also prepared. Windrows were turned weekly, and temperature, oxygen, and CO(2) in the composting mass were monitored for either 133 or 139 d. Commercial enzyme immunoassay kits were used to quantitate the levels of 17beta-estradiol and testosterone in aqueous sample extracts. Water-soluble quantities of both hormones diminished during composting. The decrease in 17beta-estradiol followed first-order kinetics, with a rate constant k = -0.010/d. Testosterone levels declined at a slightly higher rate than 17beta-estradiol (i.e., k = -0.015/d). Both hormones could still be measured in aqueous extracts of compost sampled at the conclusion of composting. The decline in water-soluble 17beta-estradiol and testosterone in extracts of clay-amended compost was not statistically different from normal compost. These data suggest that composting may be an environmentally friendly technology suitable for reducing, but not eliminating, the concentrations of these endocrine disrupting hormones at concentrated animal operation facilities.
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Evaluation of pilot-scale in-vessel composting for Hanwoo manure management.
Jeong, Kwang-Hwa; Kim, Jung Kon; Ravindran, Balsubramani; Lee, Dong Jun; Wong, Jonathan Woon-Chung; Selvam, Ammaiyappan; Karthikeyan, Obuli P; Kwag, Jung-Hoon
2017-12-01
The study investigated the effect of in-vessel composting process on Hanwoo manure in two different South Korea regions (Pyeongchang and Goechang) with sawdust using vertical cylindrical in-vessel bioreactor for 42days. The stability and quality of Hanwoo manure in both regions were improved and confirmed through the positive changes in physico-chemical and phytotoxic properties using different commercial seed crops. The pH and electrical conductivity (EC, ds/m) of composted manure in both regions were slightly increased. At the same time, carbon:nitrogen (C:N) ratio and ammonium nitrogen:nitrate nitrogen (NH 4 + -N:NO 3 - -N) ratio decreased to 13.4-16.1 and 0.36-0.37, respectively. The germination index (GI, %) index was recorded in the range of 67.6-120.9%, which was greater than 50%, indicating phytotoxin-free compost. Although, composted manure values in Goechang region were better in significant parameters, overall results confirmed that the composting process could lead to complete maturation of the composted product in both regions. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Composting of animal manures and chemical criteria for compost maturity assessment. A review.
Bernal, M P; Alburquerque, J A; Moral, R
2009-11-01
New livestock production systems, based on intensification in large farms, produce huge amount of manures and slurries without enough agricultural land for their direct application as fertilisers. Composting is increasingly considered a good way for recycling the surplus of manure as a stabilised and sanitised end-product for agriculture, and much research work has been carried out in the last decade. However, high quality compost should be produced to overcome the cost of composting. In order to provide and review the information found in the literature about manure composting, the first part of this paper explains the basic concepts of the composting process and how manure characteristics can influence its performance. Then, a summary of those factors such as nitrogen losses (which directly reduce the nutrient content), organic matter humification and compost maturity which affect the quality of composts produced by manure composting is presented. Special attention has been paid to the relevance of using an adequate bulking agent for reducing N-losses and the necessity of standardising the maturity indices due to their great importance amongst compost quality criteria.
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Wang, Ke; Wu, Yiqi; Li, Weiguang; Wu, Chuandong; Chen, Zhiqiang
2018-03-01
Mature compost recycling is widely used to reduce the dosage of organic bulking agent in actual composting process. In this study, the effects of mature compost amendment on N 2 O emission and denitrification genes were investigated in 47 days composting of sewage sludge and rice husks. The results showed that mature compost amendment dramatically augmented N 2 O emission rate in mesophilic phase and CO 2 emission rate in thermophilic phase of composting, respectively. The cumulative amount of N 2 O emission increased by more than 23 times compared to the control. Mature compost amendment not only reduced moisture and pH, but also significantly increased NO 3 - -N and NO 2 - -N concentrations. The correlation matrices indicated that NO 3 - -N, narG and norB were the main factors influencing N 2 O emission rate in sludge composting with mature compost recycling, but the N 2 O emission rate was significantly correlated to NO 2 - -N, nirK and norB in the control. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Castaldi, Paola; Garau, Giovanni; Melis, Pietro
2008-01-01
In this work the dynamics of biochemical (enzymatic activities) and chemical (water-soluble fraction) parameters during 100 days of municipal solid wastes composting were studied to evaluate their suitability as tools for compost characterization. The hydrolase (protease, urease, cellulase, beta-glucosidase) and dehydrogenase activities were characterized by significant changes during the first 2 weeks of composting, because of the increase of easily decomposable organic compounds. After the 4th week a "maturation phase" was identified in which the enzymatic activities tended to gently decrease, suggesting the stabilisation of organic matter. Also the water-soluble fractions (water-soluble carbon, nitrogen, carbohydrates and phenols), which are involved in many degradation processes, showed major fluctuations during the first month of composting. The results obtained showed that the hydrolytic activities and the water-soluble fractions did not vary statistically during the last month of composting. Significant correlations between the enzymatic activities, as well as between enzyme activities and water-soluble fractions, were also highlighted. These results highlight the suitability of both enzymatic activities and water soluble fractions as suitable indicators of the state and evolution of the organic matter during composting. However, since in the literature the amount of each activity or fraction at the end of composting depends on the raw material used for composting, single point determinations appear inadequate for compost characterization. This emphasizes the importance of the characterization of the dynamics of enzymatic activities and water-soluble fractions during the process.
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Ozaki, Noriatsu; Nakazato, Akihiro; Nakashima, Kazuki; Kindaichi, Tomonori; Ohashi, Akiyoshi
2017-12-15
Although the production of compost from sewage sludge is well established in developed countries, the use of sludge-based compost may represent a source of pollutants. The present study assessed the levels of potentially harmful compounds in compost as well as their rates of decrease during composting. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs), three fragrance compounds (OTNE, HHCB and AHTN) and triclosan were determined in the initial sewage sludge and in compost over the span of 1year. Simultaneously, the toxicity to luminescent bacteria (Aliivibrio fischeri) and aryl hydrocarbon receptor reactivity of organic solvent extracts of sludge and compost samples were assessed. Higher PAH, fragrance compounds, and triclosan concentrations were found in sewage sludge from urban areas compared with rural regions, and the urban sludge was also more toxic than the rural sludge. The high pollutant concentrations in urban sludge raised the concentrations of these compounds in the raw materials for composting and in the resulting composts. The organic matter was decomposed by 65% during the composting process, and the measured toxic substances were decreased by a similar amount, with the exception of triclosan, which decreased by only 35%. The toxicity to A. fischeri decreased to a greater extent (90%) than did the organic matter, while the aryl hydrocarbon receptor reactivity decreased by only 35%. This lower decrease coincided with that of the aryl hydrocarbon receptor-reactive PAHs (37%). Copyright © 2017 Elsevier B.V. All rights reserved.
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Cayuela, Maria Luz; Sánchez-Monedero, Miguel Angel; Roig, Asunción; Sinicco, Tania; Mondini, Claudio
2012-06-01
Nitrogen availability plays a critical role in the biodegradation of organic matter during composting. Although the optimal initial C/N is known to be around 25-30, the chemical form in which N is present influences microbial activity and therefore degradation rate and gaseous losses. This study was conducted to evaluate the influence of N availability on the composting of a mixture of lignocellulosic materials. Three composting piles were made of a mixture of wheat straw and cotton waste, each pile containing different N-rich animal by-products. The evolution of the main physico-chemical parameters was monitored (temperature, pH, electrical conductivity, C/N, NH(4)(+), NO(3)(-), water soluble C and N) as well as the enzymatic activity related to the cycle of the main nutrients (β-glucosidase, protease, alkaline phosphatase and fluorescein diacetate hydrolysis). Additionally, fluxes of CO(2), CH(4) and N(2)O emitted from the composting piles were measured by the closed-chamber technique. Cumulative CO(2) emissions were fitted to five different kinetic models with biological significance to C mineralization data. The application of the different N-rich residues had a significant effect on the C and N dynamics during composting. However, most enzymatic activities followed similar patterns in the three piles. The major CO(2) fluxes were recorded during the thermophilic phase, showing a direct relationship with temperature peaks. No CH(4) fluxes were detected for any of the composting piles during the whole trial, whereas low N(2)O emissions were found at the early beginning and during the maturation stage. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Composting and compost utilization: accounting of greenhouse gases and global warming contributions.
Boldrin, Alessio; Andersen, Jacob K; Møller, Jacob; Christensen, Thomas H; Favoino, Enzo
2009-11-01
Greenhouse gas (GHG) emissions related to composting of organic waste and the use of compost were assessed from a waste management perspective. The GHG accounting for composting includes use of electricity and fuels, emissions of methane and nitrous oxide from the composting process, and savings obtained by the use of the compost. The GHG account depends on waste type and composition (kitchen organics, garden waste), technology type (open systems, closed systems, home composting), the efficiency of off-gas cleaning at enclosed composting systems, and the use of the compost. The latter is an important issue and is related to the long-term binding of carbon in the soil, to related effects in terms of soil improvement and to what the compost substitutes; this could be fertilizer and peat for soil improvement or for growth media production. The overall global warming factor (GWF) for composting therefore varies between significant savings (-900 kg CO(2)-equivalents tonne(-1) wet waste (ww)) and a net load (300 kg CO(2)-equivalents tonne( -1) ww). The major savings are obtained by use of compost as a substitute for peat in the production of growth media. However, it may be difficult for a specific composting plant to document how the compost is used and what it actually substitutes for. Two cases representing various technologies were assessed showing how GHG accounting can be done when specific information and data are available.
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Galliou, F; Markakis, N; Fountoulakis, M S; Nikolaidis, N; Manios, T
2018-05-01
Olive mill wastewater (OMW) is generated during the production of olive oil. Its disposal is still a major environmental problem in Mediterranean countries, despite the fact that a large number of technologies have been proposed up to date. The present work examines for the first time a novel, simple and low-cost technology for OMW treatment combining solar drying and composting. In the first step, OMW was dried in a chamber inside a solar greenhouse using swine manure as a bulking agent. The mean evaporation rate was found to be 5.2 kg H 2 O/m 2 /d for a drying period of 6 months (February-August). High phenol (75%) and low nitrogen (15%) and carbon (15%) losses were recorded at the end of the solar drying process. The final product after solar drying was rich in nutrients (N: 27.8 g/kg, P: 7.3 g/kg, K: 81.6 g/kg) but still contained significant quantities of phenols (18.4 g/kg). In order to detoxify the final product, a composting process was applied as a second step with or without the use of grape marc as bulking agent. Results showed that the use of grape marc as a bulking agent at a volume ratio of 1:1 achieved a higher compost temperature profile (60 °C) than 2:1 (solar drying product: grape marc) or no use (solar drying product). The end product after the combination of solar drying and composting had the characteristics of an organic fertilizer (57% organic carbon) rich in nutrients (3.5% N, 1% P, 6.5% K) with quite low phenol content (2.9 g/kg). Finally, the use of this product for the cultivation of pepper plants approved its fertility which was found similar with commercial NPK fertilizers. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Characterization of Explosives Processing Waste Decomposition Due to Composting
1991-11-01
volume % of soil in the compost. The amendment mixture was 30% sawdust, 15% apple pomace, 20% chicken manure, and 35% chopped potato waste. The negative...experiments. 3.3 Dkictiion Naturally occurring soil- and sediment-dwelling microbes produce a diverse array of exo- and endoenzymes that can degrade...consortia of microbes . Additionally, the loss of TNT by microbial processes was accompanied by commensurate reductions in compost leachate toxicity and
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Investigation of biomethylation of arsenic and tellurium during composting.
Diaz-Bone, Roland A; Raabe, Maren; Awissus, Simone; Keuter, Bianca; Menzel, Bernd; Küppers, Klaus; Widmann, Renatus; Hirner, Alfred V
2011-05-30
Though the process of composting features a high microbiological activity, its potential to methylate metals and metalloids has been little investigated so far in spite of the high impact of this process on metal(loid) toxicity and mobility. Here, we studied the biotransformation of arsenic, tellurium, antimony, tin and germanium during composting. Time resolved investigation revealed a highly dynamic process during self-heated composting with markedly differing time patterns for arsenic and tellurium species. Extraordinary high concentrations of up to 150 mg kg(-1) methylated arsenic species as well as conversion rates up to 50% for arsenic and 5% for tellurium were observed. In contrast, little to no conversion was observed for antimony, tin and germanium. In addition to experiments with metal(loid) salts, composting of arsenic hyperaccumulating ferns Pteris vittata and P. cretica grown on As-amended soils was studied. Arsenic accumulated in the fronds was efficiently methylated resulting in up to 8 mg kg(-1) methylated arsenic species. Overall, these studies indicate that metal(loid)s can undergo intensive biomethylation during composting. Due to the high mobility of methylated species this process needs to be considered in organic waste treatment of metal(loid) contaminated waste materials. Copyright © 2010 Elsevier B.V. All rights reserved.
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[Application of microbial fuel cell (MFC) in solid waste composting].
Cui, Jinxin; Wang, Xin; Tang, Jingchun
2012-03-01
Microbial fuel cell (MFC) is a new technology that can recover energy from biomass with simultaneous waste treatment. This technique has been developed fast in recent years in combining with environmental techniques such as wastewater treatment, degradation of toxic pollutants and desalination. With the increase of solid waste, applying MFC in composting is promising due to its property of waste disposal with simultaneous energy generation. In this paper, the microbial community of MFCs during composting was summarized. Four major influencing factors including electrodes, separators, oxygen supplement and configurations on the performance of composting MFCs were discussed. The characteristics of composting MFC as a new technique for reducing solid waste were as follows: high microbial biomass resulted in the high current density; adaptable to different environmental conditions; self-adjustable temperature with high energy efficiency; the transportation of proton from anode to cathode were limited by different solid substrates.
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Universal ligation-detection-reaction microarray applied for compost microbes
Hultman, Jenni; Ritari, Jarmo; Romantschuk, Martin; Paulin, Lars; Auvinen, Petri
2008-01-01
Background Composting is one of the methods utilised in recycling organic communal waste. The composting process is dependent on aerobic microbial activity and proceeds through a succession of different phases each dominated by certain microorganisms. In this study, a ligation-detection-reaction (LDR) based microarray method was adapted for species-level detection of compost microbes characteristic of each stage of the composting process. LDR utilises the specificity of the ligase enzyme to covalently join two adjacently hybridised probes. A zip-oligo is attached to the 3'-end of one probe and fluorescent label to the 5'-end of the other probe. Upon ligation, the probes are combined in the same molecule and can be detected in a specific location on a universal microarray with complementary zip-oligos enabling equivalent hybridisation conditions for all probes. The method was applied to samples from Nordic composting facilities after testing and optimisation with fungal pure cultures and environmental clones. Results Probes targeted for fungi were able to detect 0.1 fmol of target ribosomal PCR product in an artificial reaction mixture containing 100 ng competing fungal ribosomal internal transcribed spacer (ITS) area or herring sperm DNA. The detection level was therefore approximately 0.04% of total DNA. Clone libraries were constructed from eight compost samples. The LDR microarray results were in concordance with the clone library sequencing results. In addition a control probe was used to monitor the per-spot hybridisation efficiency on the array. Conclusion This study demonstrates that the LDR microarray method is capable of sensitive and accurate species-level detection from a complex microbial community. The method can detect key species from compost samples, making it a basis for a tool for compost process monitoring in industrial facilities. PMID:19116002
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Potential Re-utilization of Composted Mangrove Litters for Pond Environment Quality Improvement
NASA Astrophysics Data System (ADS)
Dwi Hastuti, Endah; Budi Hastuti, Rini; Hariyati, Riche
2018-05-01
Production of mangrove litter from pruning and thinning activities is potential source of organic materials which could be re-utilized to improve pond environment quality and fertility. This research aimed to analyze the nutrient composition compost produced from mangrove litter and to describe the effect of compost application on pond quality. This research was conducted through two phases, including composting trial and application of compost on pond trial. Composting process was conducted for 45-60 days on mangrove litter achieved from pruning activities in the silvofishery pond using composting container, while application of compost in pond was conducted by pouring 2 kg of compost in 25 m2 pond. Production of compost included solid compost and liquid compost. Nutrient concentration of solid compost was ranged from 0.47-0.52% for N; 0.36-0.44% for P; and 5.45-6.39% for organic C, while liquid compost provided 0.62-0.69%; 0.24-0.32%; and 3.98-4.45% respectively for N, P and organic C. While C/N ratio was ranged from 11.60-12.78 and 5.77-7.18 respectively for solid and liquid compost. Solid compost quality resulted that N, P and C/N ration had fulfilled the standart criteria defined by Indonesia National Standart for compost. Observed impact of compost application on pond water quality were the improvement of water clarity and increasing abundance of klekap (lab-lab). This showed that mangrove litters could be converted into a more productive materials to enhance pond environment quality and productivity, decrease management cost and increase benefit. Scheduled fertilization with compost is suggested to be conducted to provide best benefit on silvofishery management.
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Vandecasteele, B; Willekens, K; Zwertvaegher, A; Degrande, L; Tack, F M G; Du Laing, G
2013-11-01
Micronutrient content and availability in composts may be affected by the addition of wood chips or tree bark as a bulking agent in the compost feedstock. In the first part of this study, micronutrient levels were assessed in bark and wood of poplar and willow clones in a short-rotation coppice. Large differences between species were observed in bark concentrations for Cd, Zn and Mn. In the second part of the study, we aimed to determine the effect of feedstock composition and composting on Cd, Zn and Mn concentrations and availability. By means of three composting experiments we examined the effect of (a) bark of different tree species, (b) the amount of bark, and (c) the use of bark versus wood chips. In general, compost characteristics such as pH, organic matter and nutrient content varied due to differences in feedstock mixture and composting process. During the composting process, the availability of Cd, Zn and Mn decreased, although the use of willow and poplar bark or wood chips resulted in elevated total Cd, Zn or Mn concentrations in the compost. Cd concentrations in some composts even exceeded legal criteria. Cd and Zn were mainly bound in the reducible fraction extracted with 0.5M NH2OH⋅HCl. A higher acid-extractable fraction for Mn than for Cd and Zn was found. Higher Cd concentrations in the compost due to the use of bark or wood chips did not result in higher risk of Cd leaching. The results of the pH-stat experiment with gradual acidification of composts illustrated that only a strong pH decline in the compost results in higher availability of Cd, Zn and Mn. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Heck, Karina; De Marco, Évilin Giordana; Duarte, Mariana Wanderlei; Salamoni, Sabrina Pinto; Van Der Sand, Sueli
2015-06-01
The composting process is a viable alternative for the recycling of household organic waste and sewage sludge generated during wastewater treatment. However, this technique can select microorganisms resistant to antimicrobials and heavy metals as a result of excess chemicals present in compost windrow. This study evaluates the antimicrobial multiresistant and tolerance to heavy metals in bacteria isolated from the composting process with sewage sludge. Fourteen antimicrobials were used in 344 strains for the resistance profile and four heavy metals (chromium, copper, zinc, and lead) for the minimum biocide concentration assay. The strains used were from the sewage sludge sample (beginning of the process) and the compost sample (end of the process). Strains with higher antimicrobial and heavy metal profile were identified by 16S rRNA gene sequencing. The results showed a multiresistant profile in 48 % of the strains, with the highest percentage of strains resistant to nitrofurantoin (65 %) and β-lactams (58 %). The strains isolated from the sewage sludge and the end of the composting process were more tolerant to copper, with a lethal dose of approximately 900 mg L(-1) for about 50 % of the strains. The genera that showed the highest multiresistant profile and increased tolerance to the metals tested were Pseudomonas and Ochrobactrum. The results of this study may contribute to future research and the revision and regulation of legislation on sewage sludge reuse in soils.
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Rao, Juluri R; Watabe, Miyuki; Stewart, T Andrew; Millar, B Cherie; Moore, John E
2007-01-01
In Ireland, conversion of biodegradable farm wastes such as pig manure spent mushroom compost and poultry litter wastes to pelletised fertilisers is a desirable option for farmers. In this paper, results obtained from the composting of pig waste solids (20% w/w) blended with other locally available biodegradable wastes comprising poultry litter (26% w/w), spent mushroom compost (26% w/w), cocoa husks (18% w/w) and moistened shredded paper (10% w/w) are presented. The resulting 6-mo old 'mature' composts had a nutrient content of 2.3% total N, 1.6% P and 3.1% K, too 'low' for direct use as an agricultural fertiliser. Formulations incorporating dried blood or feather meal amendments enriched the organic N-content, reduced the moisture in mature compost mixtures and aided the granulation process. Inclusion of mineral supplements viz., sulphate of ammonia, rock phosphate and sulphate of potash, yielded slow release fertilisers with nutrient N:P:K ratios of 10:3:6 and 3:5:10 that were suited for amenity grasslands such as golf courses for spring or summer application and autumn dressing, respectively. Rigorous microbiological tests carried out throughout the composting, processing and pelletising phases indicated that the formulated organo-mineral fertilisers were free of vegetative bacterial pathogens.
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Yu, Minda; He, Xiaosong; Liu, Jiaomei; Wang, Yuefeng; Xi, Beidou; Li, Dan; Zhang, Hui; Yang, Chao
2018-04-14
Understanding the heterogeneous evolution characteristics of dissolved organic matter fractions derived from compost is crucial to exploring the composting biodegradation process and the possible applications of compost products. Herein, two-dimensional correlation spectroscopy integrated with reversed-phase high performance liquid chromatography and size exclusion chromatography were utilized to obtain the molecular weight (MW) and polarity evolution characteristics of humic acid (HA), fulvic acid (FA), and the hydrophilic (HyI) fractions during composting. The high-MW humic substances and building blocks in the HA fraction degraded faster during composting than polymers, proteins, and organic colloids. Similarly, the low MW acid FA factions transformed faster than the low weight neutral fractions, followed by building blocks, and finally polymers, proteins, and organic colloids. The evolutions of HyI fractions during composting occurred first for building blocks, followed by low MW acids, and finally low weight neutrals. With the progress of composting, the hydrophobic properties of the HA and FA fractions were enhanced. The degradation/humification process of the hydrophilic and transphilic components was faster than that of the hydrophobic component. Compared with the FA and HyI fractions, the HA fraction exhibited a higher MW and increased hydrophobicity. Copyright © 2018 Elsevier B.V. All rights reserved.
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Effects of earthworm casts and zeolite on the two-stage composting of green waste
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Lu, E-mail: zhanglu1211@gmail.com; Sun, Xiangyang, E-mail: xysunbjfu@gmail.com
2015-05-15
Highlights: • Earthworm casts (EWCs) and clinoptilolite (CL) were used in green waste composting. • Addition of EWCs + CL improved physico-chemical and microbiological properties. • Addition of EWCs + CL extended the duration of thermophilic periods during composting. • Addition of EWCs + CL enhanced humification, cellulose degradation, and nutrients. • Combined addition of 0.30% EWCs + 25% CL reduced composting time to 21 days. - Abstract: Because it helps protect the environment and encourages economic development, composting has become a viable method for organic waste disposal. The objective of this study was to investigate the effects of earthwormmore » casts (EWCs) (at 0.0%, 0.30%, and 0.60%) and zeolite (clinoptilolite, CL) (at 0%, 15%, and 25%) on the two-stage composting of green waste. The combination of EWCs and CL improved the conditions of the composting process and the quality of the compost products in terms of the thermophilic phase, humification, nitrification, microbial numbers and enzyme activities, the degradation of cellulose and hemicellulose, and physico-chemical characteristics and nutrient contents of final composts. The compost matured in only 21 days with the optimized two-stage composting method rather than in the 90–270 days required for traditional composting. The optimal two-stage composting and the best quality compost were obtained with 0.30% EWCs and 25% CL.« less
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Kim, Jung Kon; Lee, Dong Jun; Ravindran, Balsubramani; Jeong, Kwang-Hwa; Wong, Jonathan Woon-Chung; Selvam, Ammaiyappan; Karthikeyan, Obuli P; Kwag, Jung-Hoon
2017-12-01
The study investigated the effect of different initial moisture (IM) content (55, 60, 65, and 70%) of composting mixtures (swine manure and sawdust) for the production of nutrient rich manure, and the recovery of ammonia through a condensation process using a vertical cylindrical in-vessel composter for 56days. The composting resulted in a significant reduction in C:N ratio and electrical conductivity (EC), with a slight increase in pH in all products. The NH 3 were emitted notably, and at the same time the NO 3 - -N concentration gradually increased with the reduction of NH 4 + -N in the composting mixtures. The overall results confirmed, the 65% IM showed the maximum nutritional yield, maturity and non-phytotoxic effects (Lycopersicon esculentum L.), with the results of ideal compost product in the following order of IM: 65%>60%>70%>55%. Finally, the recovered condensed ammonia contained considerable ammonium nitrogen concentrations and could be used as fertilizer. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Diversity and abundance of ammonia oxidizing archaea in tropical compost systems
de Gannes, Vidya; Eudoxie, Gaius; Dyer, David H.; Hickey, William J.
2012-01-01
Composting is widely used to transform waste materials into valuable agricultural products. In the tropics, large quantities of agricultural wastes could be potentially useful in agriculture after composting. However, while microbiological processes of composts in general are well established, relatively little is known about microbial communities that may be unique to these in tropical systems, particularly nitrifiers. The recent discovery of ammonia oxidizing archaea (AOA) has changed the paradigm of nitrification being initiated solely by ammonia oxidizing bacteria. In the present study, AOA abundance and diversity was examined in composts produced from combinations of plant waste materials common in tropical agriculture (rice straw, sugar cane bagasse, and coffee hulls), which were mixed with either cow- or sheep-manure. The objective was to determine how AOA abundance and diversity varied as a function of compost system and time, the latter being a contrast between the start of the compost process (mesophilic phase) and the finished product (mature phase). The results showed that AOA were relatively abundant in composts of tropical agricultural wastes, and significantly more so than were the ammonia-oxidizing bacteria. Furthermore, while the AOA communities in the composts were predominatly group I.1b, the communities were diverse and exhibited structures that diverged between compost types and phases. These patterns could be taken as indicators of the ecophysiological diversity in the soil AOA (group I.1b), in that significantly different AOA communties developed when exposed to varying physico-chemical environments. Nitrification patterns and levels differed in the composts which, for the mature material, could have significant effects on its performance as a plant growth medium. Thus, it will also be important to determine the association of AOA (and diversity in their communities) with nitrification in these systems. PMID:22787457
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Montejo, C; Costa, C; Márquez, M C
2015-10-01
Certain controversy exists about the use of compost from MSW (municipal solid waste) and, specifically, from the organic fraction of MSW that has not been separated at the source. In this case, the final composition of MSW compost is related to the performance of the separation process in MBT (Mechanical and Biological Treatment) plants as well as the composition of raw materials and the particular features of composting systems. In an effort to investigate the quality of MSW compost, 30 samples of this product obtained from 10 different MBT plants were studied. The main physical and chemical properties were analyzed and were compared with the requirements of current legislation. The composting systems used to produce these compost samples were studied and the input materials were characterized. The results reveal that the heavy metal content in MSW compost was below the legal restrictions in all samples but one; however, in most of them the percentage of Pb was high. The fertilizing potential of MSW compost has been demonstrated by its high nutrient concentrations, particularly N, K, P, Ca and Mg. Nevertheless, here the percentage of inert impurities with a size larger than 2 mm, such as plastic or glass, was seen to be excessively high exceeding in some cases the legal limit. The source of such pollution lies in the composting inputs, OFMSW (organic fraction of MSW), which showed high percentages of improper materials such as plastic (9%) or glass (11%). Accordingly, the performance of the sorting stage for the collection of the raw material must be improved, as must the refining process, since this does not remove the necessary amounts of these impurities from the final compost. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Nitrogen availability in composted poultry litter using natural amendments.
Turan, N Gamze
2009-02-01
Poultry litter compost is used as fertilizer on agricultural land because of its high nutrient content. A major limitation of land application of poultry litter compost is the loss of nitrogen via NH3 volatilization. The present work was conducted to monitor nitrogen availability during composting of poultry litter with natural zeolite, expanded perlite, pumice and expanded vermiculite. Poultry litter was composted for 100 days using five in-vessel composting simulators with a volumetric ratio of natural materials:poultry litter of 1:10. It was found that natural materials significantly reduced NH3 volatilization. At the end of the process, the control treatment without any natural materials had the lowest rate of total N: 72% of the initial total N was lost from the compost made with no amendment, while 53, 42, 26 and 16% of initial total N was lost from compost containing expandable perlite, expandable vermiculite, pumice and natural zeolite, respectively.
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Chai, E W; H'ng, P S; Peng, S H; Wan-Azha, W M; Chin, K L; Chow, M J; Wong, W Z
2013-01-01
In Malaysia, large amounts of organic materials, which lead to disposal problems, are generated from agricultural residues especially from palm oil industries. Increasing landfill costs and regulations, which limit many types of waste accepted at landfills, have increased the interest in composting as a component of waste management. The objectives of this study were to characterize compost feedstock properties of common organic waste materials available in Malaysia. Thus, a ratio modelling of matching ingredients for empty fruit bunches (EFBs) co-composting using different organic materials in Malaysia was done. Organic waste materials with a C/N ratio of < 30 can be applied as a nitrogen source in EFB co-composting. The outcome of this study suggested that the percentage of EFB ranged between 50% and 60%, which is considered as the ideal mixing ratio in EFB co-composting. Conclusively, EFB can be utilized in composting if appropriate feedstock in term of physical and chemical characteristics is coordinated in the co-composting process.
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McGee, C F; Byrne, H; Irvine, A; Wilson, J
2017-01-01
Commercial cultivation of the button mushroom Agaricus bisporus is performed through the inoculation of a semipasteurized composted material. Pasteurization of the compost material prior to inoculation results in a substrate with a fungal community that becomes dominated by A. bisporus. However, little is known about the composition and activity in the wider fungal community beyond the presence of A. bisporus in compost throughout the mushroom cropping process. In this study, the fungal cropping compost community was characterized by sequencing nuc rDNA ITS1-5.8S-ITS2 amplified from extractable DNA and RNA. The fungal community generated from DNA extracts identified a diverse community containing 211 unique species, although only 51 were identified from cDNA. Agaricus bisporus was found to dominate in the DNA-derived fungal community for the duration of the cropping process. However, analysis of cDNA extracts found A. bisporus to dominate only up to the first crop flush, after which activity decreased sharply and a much broader fungal community became active. This study has highlighted the diverse fungal community that is present in mushroom compost during cropping.
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Puyuelo, B; Gea, T; Sánchez, A
2014-08-01
In this study, we have evaluated different strategies for the optimization of the aeration during the active thermophilic stage of the composting process of source-selected Organic Fraction of Municipal Solid Waste (or biowaste) using reactors at bench scale (50L). These strategies include: typical cyclic aeration, oxygen feedback controller and a new self-developed controller based on the on-line maximization of the oxygen uptake rate (OUR) during the process. Results highlight differences found in the emission of most representative greenhouse gases (GHG) emitted from composting (methane and nitrous oxide) as well as in gases typically related to composting odor problems (ammonia as typical example). Specifically, the cyclic controller presents emissions that can double that of OUR controller, whereas oxygen feedback controller shows a better performance with respect to the cyclic controller. A new parameter, the respiration index efficiency, is presented to quantitatively evaluate the GHG emissions and, in consequence, the main negative environmental impact of the composting process. Other aspects such as the stability of the compost produced and the consumption of resources are also evaluated for each controller. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Glanville, Thomas D; Ahn, Heekwon; Akdeniz, Neslihan; Crawford, Benjamin P; Koziel, Jacek A
2016-02-01
A passively-ventilated plastic-wrapped composting system initially developed for biosecure disposal of poultry mortalities caused by avian influenza was adapted and tested to assess its potential as an emergency disposal option for disease-related swine mortalities. Fresh air was supplied through perforated plastic tubing routed through the base of the compost pile. The combined air inlet and top vent area is ⩽∼1% of the gas exchange surface of a conventional uncovered windrow. Parameters evaluated included: (1) spatial and temporal variations in matrix moisture content (m.c.), leachate production, and matrix O2 concentrations; (2) extent of soft tissue decomposition; and (3) internal temperature and the success rate in achieving USEPA time/temperature (T) criteria for pathogen reduction. Six envelope materials (wood shavings, corn silage, ground cornstalks, ground oat straw, ground soybean straw, or ground alfalfa hay) and two initial m.c.'s (15-30% w.b. for materials stored indoors, and 45-65% w.b. to simulate materials exposed to precipitation) were tested to determine their effect on performance parameters (1-3). Results of triple-replicated field trials showed that the composting system did not accumulate moisture despite the 150kg carcass water load (65% of 225kg total carcass mass) released during decomposition. Mean compost m.c. in the carcass layer declined by ∼7 percentage points during 8-week trials, and a leachate accumulation was rare. Matrix O2 concentrations for all materials other than silage were ⩾10% using the equivalent of 2m inlet/vent spacing. In silage O2 dropped below 5% in some cases even when 0.5m inlet/vent spacing was used. Eight week soft tissue decomposition ranged from 87% in cornstalks to 72% in silage. Success rates for achievement of USEPA Class B time/temperature criteria ranged from 91% for silage to 33-57% for other materials. Companion laboratory biodegradation studies suggest that Class B success rates can be improved by slightly increasing envelope material m.c. Moistening initially dry (15% m.c.) envelope materials to 35% m.c. nearly doubled their heat production potential, boosting it to levels ⩾silage. The 'contradictory' silage test results showing high temperatures paired with slow soft tissue degradation are likely due to this material's high density, low gas permeability and low water vapor loss. While slow decomposition typically suggests low microbial activity and heat production, it does not rule out high internal temperatures if the heat produced is conserved. Occasional short-term odor releases during the first 2weeks of composting were associated with top-to-bottom gas flow which is contrary to the typical bottom-to-top flow typically observed in conventional compost piles. In cases where biosecurity concerns are paramount, results of this study show the plastic-wrapped passively-ventilated composting method to have good potential for above-ground swine mortality disposal. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Thermophilic aeration of cattle slurry with whey and/or jam wastes.
Heinonen-Tanski, Helvi; Kiuru, Tapio; Ruuskanen, Juhani; Korhonen, Kari; Koivunen, Jari; Ruokojärvi, Arja
2005-01-01
Thermophilic aeration of cattle slurry and food industrial by-products was studied with the aim to improve hygienic qualities of the slurry so that it could be used as a safe fertiliser for berries to be eaten raw. We also wanted to study if the process would be energetically favourable in an arctic climate. Cattle slurry alone or with whey and/or jam waste was treated. The tests were done in a well heat-insulated reactor with a 10 m(3) volume. Temperature increases up to over 70 degrees C could be recorded in 19 days even though some processes were carried out in winter time when the ambient air temperature was less than 0 degrees C. The heat energy formed was higher than the electrical energy needed to carry out the aeration. The hygienic qualities of the aerated product were good with only minor nitrogen losses. The end product could be useful as a fertiliser and soil improving compound to increase the organic matter content of agricultural soil. Cattle slurry alone was well suited as the raw material if attaining a high temperature was the main goal. A part of slurry could be replaced with food-industrial side products. Whey waste suited better for co-composting than jam waste but the mixture of whey, jam waste, and slurry was optimal for composting.
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2012-01-01
Background Understanding the dynamics of the microbial communities that, along with their secreted enzymes, are involved in the natural process of biomass composting may hold the key to breaking the major bottleneck in biomass-to-biofuels conversion technology, which is the still-costly deconstruction of polymeric biomass carbohydrates to fermentable sugars. However, the complexity of both the structure of plant biomass and its counterpart microbial degradation communities makes it difficult to investigate the composting process. Results In this study, a composter was set up with a mix of yellow poplar (Liriodendron tulipifera) wood-chips and mown lawn grass clippings (85:15 in dry-weight) and used as a model system. The microbial rDNA abundance data obtained from analyzing weekly-withdrawn composted samples suggested population-shifts from bacteria-dominated to fungus-dominated communities. Further analyses by an array of optical microscopic, transcriptional and enzyme-activity techniques yielded correlated results, suggesting that such population shifts occurred along with early removal of hemicellulose followed by attack on the consequently uncovered cellulose as the composting progressed. Conclusion The observed shifts in dominance by representative microbial groups, along with the observed different patterns in the gene expression and enzymatic activities between cellulases, hemicellulases, and ligninases during the composting process, provide new perspectives for biomass-derived biotechnology such as consolidated bioprocessing (CBP) and solid-state fermentation for the production of cellulolytic enzymes and biofuels. PMID:22490508
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Wei, H.; Tucker, M. P.; Baker, J. O.
2012-04-01
Understanding the dynamics of the microbial communities that, along with their secreted enzymes, are involved in the natural process of biomass composting may hold the key to breaking the major bottleneck in biomass-to-biofuels conversion technology, which is the still-costly deconstruction of polymeric biomass carbohydrates to fermentable sugars. However, the complexity of both the structure of plant biomass and its counterpart microbial degradation communities makes it difficult to investigate the composting process. In this study, a composter was set up with a mix of yellow poplar (Liriodendron tulipifera) wood-chips and mown lawn grass clippings (85:15 in dry-weight) and used as amore » model system. The microbial rDNA abundance data obtained from analyzing weekly-withdrawn composted samples suggested population-shifts from bacteria-dominated to fungus-dominated communities. Further analyses by an array of optical microscopic, transcriptional and enzyme-activity techniques yielded correlated results, suggesting that such population shifts occurred along with early removal of hemicellulose followed by attack on the consequently uncovered cellulose as the composting progressed. The observed shifts in dominance by representative microbial groups, along with the observed different patterns in the gene expression and enzymatic activities between cellulases, hemicellulases, and ligninases during the composting process, provide new perspectives for biomass-derived biotechnology such as consolidated bioprocessing (CBP) and solid-state fermentation for the production of cellulolytic enzymes and biofuels.« less
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Bastida, F; Jehmlich, N; Lima, K; Morris, B E L; Richnow, H H; Hernández, T; von Bergen, M; García, C
2016-03-01
The linkage between phylogenetic and functional processes may provide profound insights into the effects of hydrocarbon contamination and biodegradation processes in high-diversity environments. Here, the impacts of petroleum contamination and the bioremediation potential of compost amendment, as enhancer of the microbial activity in semiarid soils, were evaluated in a model experiment. The analysis of phospholipid fatty-acids (PLFAs) and metaproteomics allowed the study of biomass, phylogenetic and physiological responses of the microbial community in polluted semiarid soils. Petroleum pollution induced an increase of proteobacterial proteins during the contamination, while the relative abundance of Rhizobiales lowered in comparison to the non-contaminated soil. Despite only 0.55% of the metaproteome of the compost-treated soil was involved in biodegradation processes, the addition of compost promoted the removal of polycyclic aromatic hydrocarbons (PAHs) and alkanes up to 88% after 50 days. However, natural biodegradation of hydrocarbons was not significant in soils without compost. Compost-assisted bioremediation was mainly driven by Sphingomonadales and uncultured bacteria that showed an increased abundance of catabolic enzymes such as catechol 2,3-dioxygenases, cis-dihydrodiol dehydrogenase and 2-hydroxymuconic semialdehyde. For the first time, metaproteomics revealed the functional and phylogenetic relationships of petroleum contamination in soil and the microbial key players involved in the compost-assisted bioremediation. Copyright © 2015 Elsevier B.V. All rights reserved.
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Role of biochar as an additive in organic waste composting.
Sanchez-Monedero, M A; Cayuela, M L; Roig, A; Jindo, K; Mondini, C; Bolan, N
2018-01-01
The use of biochar in organic waste composting has attracted interest in the last decade due to the environmental and agronomical benefits obtained during the process. Biochar presents favourable physicochemical properties, such as large porosity, surface area and high cation exchange capacity, enabling interaction with major nutrient cycles and favouring microbial growth in the composting pile. The enhanced environmental conditions can promote a change in the microbial communities that can affect important microbially mediated biogeochemical cycles: organic matter degradation and humification, nitrification, denitrification and methanogenesis. The main benefits of the use of biochar in composting are reviewed in this article, with special attention to those related to the process performance, compost microbiology, organic matter degradation and humification, reduction of N losses and greenhouse gas emissions and fate of heavy metals. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
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Image parameters for maturity determination of a composted material containing sewage sludge
NASA Astrophysics Data System (ADS)
Kujawa, S.; Nowakowski, K.; Tomczak, R. J.; Boniecki, P.; Dach, J.
2013-07-01
Composting is one of the best methods for management of sewage sludge. In a reasonably conducted composting process it is important to early identify the moment in which a material reaches the young compost stage. The objective of this study was to determine parameters contained in images of composted material's samples that can be used for evaluation of the degree of compost maturity. The study focused on two types of compost: containing sewage sludge with corn straw and sewage sludge with rapeseed straw. The photographing of the samples was carried out on a prepared stand for the image acquisition using VIS, UV-A and mixed (VIS + UV-A) light. In the case of UV-A light, three values of the exposure time were assumed. The values of 46 parameters were estimated for each of the images extracted from the photographs of the composted material's samples. Exemplary averaged values of selected parameters obtained from the images of the composted material in the following sampling days were presented. All of the parameters obtained from the composted material's images are the basis for preparation of training, validation and test data sets necessary in development of neural models for classification of the young compost stage.
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Soobhany, Nuhaa; Mohee, Romeela; Garg, Vinod Kumar
2017-06-01
Waste management strategies for organic residues, such as composting and vermicomposting, have been implemented in some developed and developing countries to solve the problem of organic solid waste (OSW). Yet, these biological treatment technologies do not always result in good quality compost or vermicompost with regards to sanitation capacity owing to the presence of bacterial pathogenic substances in objectionable concentrations. The presence of pathogens in soil conditioners poses a potential health hazard and their occurrence is of particular significance in composts and/or vermicomposts produced from organic materials. Past and present researches demonstrated a high-degree of agreement that various pathogens survive after the composting of certain OSW but whether similar changes in bacterial pathogenic loads arise during vermitechnology has not been thoroughly elucidated. This review garners information regarding the status of various pathogenic bacteria which survived or diffused after the composting process compared to the status of these pathogens after the vermicomposting of OSW with the aim of achieving sanitation goals. This work is also indispensable for the specification of compost quality guidelines concerning pathogen loads which would be specific to treatment technology. It was hypothesized that vermicomposting process for OSW can be efficacious in sustaining the existence of pathogenic organisms most specifically; human pathogens under safety levels. In summary, earthworms can be regarded as a way of obliterating pathogenic bacteria from OSW in a manner equivalent to earthworm gut transit mechanism which classifies vermicomposting as a promising sanitation technique in comparison to composting processes. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Conza, Lisa; Casati Pagani, Simona; Gaia, Valeria
2014-11-24
The incidence of Legionnaires' disease (LD) in southern Switzerland is three times higher than in northern Switzerland. Climatic and geographic factors may be potential causes for this difference.We studied the prevalence of Legionella and free-living amoebae (FLA) in compost and bioaerosol in two Swiss regions to understand the role of climate and geography in the transmission of LD. We also tried to investigate whether or not compost storage duration would influence the composition of Legionella and FLA communities. A larger proportion of compost heaps in facilities from southern Switzerland harbor more diverse Legionella compared to the north (P=0.0146). FLA were isolated from composts in northern facilities at slightly higher rates (88.2% vs. 69.2%) and at lower rates from bioaerosols (6.3% vs. 13%) than in southern Switzerland. The diversity of FLA was higher in northern than in southern Switzerland (80% vs. 65%). A general decrease in the presence and variety of species was observed with decreasing compost storage time length. A discriminant model showed that values of vapour pressure, relative humidity and temperature distinguish the two regions, which were also characterised by different contamination rates by FLA and Legionella. The duration of outdoor storage may favour contamination of the compost by Legionella, and may increase the number and isolation of Legionella naturally occurring in compost. The climate in the south seems to favour higher Legionella contamination of compost heaps: this could explain the higher incidence of LD in southern Switzerland.
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Yang, Fan; Li, Guoxue; Shi, Hong; Wang, Yiming
2015-02-01
This study investigated the effects of phosphogypsum and superphosphate on the maturity and gaseous emissions of composting kitchen waste. Two amended compost treatments were conducted using phosphogypsum and superphosphate as additives with the addition of 10% of initial raw materials (dry weight). A control treatment was also studied. The treatments were conducted under aerobic conditions in 60-L reactors for 35 days. Maturity indexes were determined, and continuous measurements of CH4, N2O, and NH3 were taken. Phosphogypsum and superphosphate had no negative effects on compost maturity, although superphosphate inhibited the temperature rise in the first few days. The addition of phosphogypsum and superphosphate drastically reduced CH4 emissions (by 85.8% and 80.5%, respectively) and decreased NH3 emissions (by 23.5% and 18.9%, respectively). However, a slight increase in N2O emissions (by 3.2% and 14.8%, respectively) was observed. Composting with phosphogypsum and superphosphate reduced total greenhouse gas emissions by 17.4% and 7.3% respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Wang, Rui; Zhang, Junya; Sui, Qianwen; Wan, Hefeng; Tong, Juan; Chen, Meixue; Wei, Yuansong; Wei, Dongbin
2016-09-01
Swine manure has been considered as the reservoir of antibiotic resistance genes (ARGs). Composting is one of the most suitable technologies for treating livestock manures, and red mud was proved to have a positive effect on nitrogen conservation during composting. This study investigated the abundance of eight tetracycline and three copper resistance genes, the bacterial community during the full scale swine manure composting with or without addition of red mud. The results showed that ARGs in swine manure could be effectively removed through composting (reduced by 2.4log copies/g TS), especially during the thermophilic phase (reduced by 1.5log copies/g TS), which the main contributor might be temperature. Additionally, evolution of bacterial community could also have a great influence on ARGs. Although addition of red mud could enhance nitrogen conservation, it obviously hindered removal of ARGs (reduced by 1.7log copies/g TS) and affected shaping of bacterial community during composting. Copyright © 2016 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Barthod, Justine; Rumpel, Cornélia; Paradelo, Remigio; Dignac, Marie-France
2016-04-01
Intensive farming practices can lead to a depletion of soil organic matter, negatively impacting important soil properties such as structural stability, fertility and C storage. The addition of organic amendments such as compost and vermicompost, rich in carbon, helps maintaining soil organic matter levels or restoring degraded soils. Composting and vermicomposting are based on stabilization of organic matter through the mineralization of easily decomposable organic matter compounds, therefore releasing greenhouse gases, including CO2. The aim of this study was to evaluate the global potential reduction of such emissions by the use of additives (2:1 clay and/or biochar): during (vermi)composting processes and after use of the final products as soil amendments. We hypothesized that the interactions between the additives and organic matter may lead to carbon stabilization and that such interactions may be enhanced by the presence of worms (Eisenia). We added in different proportions clay (25% or 50%), biochar (10%) and a mixture of biochar (10%) with clay (25%) to pre-composted green waste. The CO2 emissions of the composting and vermicomposting processes were measured during 21 days. After that, the amendments were added to a loamy cambisol soil and the CO2 emissions were monitored during 30 days of a laboratory experiment. The most efficient treatments in terms of reducing global CO2 emissions were the co-vermicomposting process with 25% clay followed by co-composting with 50% clay and with 10% biochar plus 25% clay. In this treatment (vermicompost with 25% clay), the carbon emissions were decreased by up to 44% compared to regular compost. Addition of biochar reduced CO2 emissions only during composting. Co-composting with biochar could be a promising avenue to limit global CO2 emissions whereas in presence of worms clay additions are better suited. These findings suggest that the presence of worms increased the formation of organo-mineral associations and thus C protection up to a certain clay/organic matter ratio. This strategy could be used to enhance the stability of organic amendments and increase soil carbon sequestration.
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Green waste compost as an amendment during induced phytoextraction of mercury-contaminated soil.
Smolinska, Beata
2015-03-01
Phytoextraction of mercury-contaminated soils is a new strategy that consists of using the higher plants to make the soil contaminant nontoxic. The main problem that occurs during the process is the low solubility and bioavailability of mercury in soil. Therefore, some soil amendments can be used to increase the efficiency of the Hg phytoextraction process. The aim of the investigation was to use the commercial compost from municipal green wastes to increase the efficiency of phytoextraction of mercury-contaminated soil by Lepidium sativum L. plants and determine the leaching of Hg after compost amendment. The result of the study showed that Hg can be accumulated by L. sativum L. The application of compost increased both the accumulation by whole plant and translocation of Hg to shoots. Compost did not affect the plant biomass and its biometric parameters. Application of compost to the soil decreased the leaching of mercury in both acidic and neutral solutions regardless of growing medium composition and time of analysis. Due to Hg accumulation and translocation as well as its potential leaching in acidic and neutral solution, compost can be recommended as a soil amendment during the phytoextraction of mercury-contaminated soil.
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NASA Astrophysics Data System (ADS)
Taha, M. P. M.; Drew, G. H.; Tamer, A.; Hewings, G.; Jordinson, G. M.; Longhurst, P. J.; Pollard, S. J. T.
We present bioaerosol source term concentrations from passive and active composting sources and compare emissions from green waste compost aged 1, 2, 4, 6, 8, 12 and 16 weeks. Results reveal that the age of compost has little effect on the bioaerosol concentrations emitted for passive windrow sources. However emissions from turning compost during the early stages may be higher than during the later stages of the composting process. The bioaerosol emissions from passive sources were in the range of 10 3-10 4 cfu m -3, with releases from active sources typically 1-log higher. We propose improvements to current risk assessment methodologies by examining emission rates and the differences between two air dispersion models for the prediction of downwind bioaerosol concentrations at off-site points of exposure. The SCREEN3 model provides a more precautionary estimate of the source depletion curves of bioaerosol emissions in comparison to ADMS 3.3. The results from both models predict that bioaerosol concentrations decrease to below typical background concentrations before 250 m, the distance at which the regulator in England and Wales may require a risk assessment to be completed.
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Bacterial community structure transformed after thermophilically composting human waste in Haiti
Kramer, Sasha; Roy, Monika; Reid, Francine C.; Dubinsky, Eric A.
2017-01-01
Recycling human waste for beneficial use has been practiced for millennia. Aerobic (thermophilic) composting of sewage sludge has been shown to reduce populations of opportunistically pathogenic bacteria and to inactivate both Ascaris eggs and culturable Escherichia coli in raw waste, but there is still a question about the fate of most fecal bacteria when raw material is composted directly. This study undertook a comprehensive microbial community analysis of composting material at various stages collected over 6 months at two composting facilities in Haiti. The fecal microbiota signal was monitored using a high-density DNA microarray (PhyloChip). Thermophilic composting altered the bacterial community structure of the starting material. Typical fecal bacteria classified in the following groups were present in at least half the starting material samples, yet were reduced below detection in finished compost: Prevotella and Erysipelotrichaceae (100% reduction of initial presence), Ruminococcaceae (98–99%), Lachnospiraceae (83–94%, primarily unclassified taxa remained), Escherichia and Shigella (100%). Opportunistic pathogens were reduced below the level of detection in the final product with the exception of Clostridium tetani, which could have survived in a spore state or been reintroduced late in the outdoor maturation process. Conversely, thermotolerant or thermophilic Actinomycetes and Firmicutes (e.g., Thermobifida, Bacillus, Geobacillus) typically found in compost increased substantially during the thermophilic stage. This community DNA-based assessment of the fate of human fecal microbiota during thermophilic composting will help optimize this process as a sanitation solution in areas where infrastructure and resources are limited. PMID:28570610
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lacey, Jeffrey Alan; Lee, Brady Douglas; Apel, William Arnold
2001-06-01
In 1998, 3.6 trillion kilowatt-hours of electricity were generated in the United States. Over half of this was from coal-fired power plants, resulting in more than 8.3 million tons of nitrogen oxide (NOx) compounds being released into the environment. Over 95% of the NOx compounds produced during coal combustion are in the form of nitric oxide (NO). NOx emission regulations are becoming increasingly stringent, leading to the need for new, cost effective NOx treatment technologies. Biofiltration is such a technology. NO removal efficiencies were compared in compost based biofilters using four different composts. In previous experiments, removal efficiencies were typicallymore » highest at the beginning of the experiment, and decreased as the experiments proceeded. This work tested different types of compost in an effort to find a compost that could maintain NO removal efficiencies comparable to those seen early in the previous experiments. One of the composts was wood based with manure, two were wood based with high nitrogen content sludge, and one was dairy compost. The wood based with manure and one of the wood based with sludge composts were taken directly from an active compost pile while the other two composts were received in retail packaging which had been out of active piles for an indeterminate amount of time. A high temperature (55-60°C) off-gas stream was treated in biofilters operated under denitrifying conditions. Biofilters were operated at an empty bed residence time of 13 seconds with target inlet NO concentrations of 500 ppmv. Lactate was the carbon and energy source. Compost was sampled at 10-day intervals to determine aerobic and anaerobic microbial densities. Compost was mixed at a 1:1 ratio with lava rock and calcite was added at 100g/kg of compost. In each compost tested, the highest removal efficiencies occurred within the first 10 days of the experiment. The wood based with manure peaked at day 3 (77.14%), the dairy compost at day 1 (80.74%), the active wood based with sludge at day 5 (68.15%) and the inactive wood based with sludge at day 9 (63.64%, this compost was frozen when received). These levels gradually decreased throughout the remainder of the experiment until they fell between 40% and 60%. Decreasing removal efficiency was characteristic of all the composts tested, regardless of their makeup or activity state prior to testing. Although microbial densities and composition between composts may have differed, there was little change in densities within each experiment.« less
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Li, Qunliang; Guo, Xiaobo; Lu, Yanyu; Shan, Guangchun; Huang, Junhao
2016-10-01
To investigate the impacts of flue gas desulphurization gypsum (FGDG) amendment on the nitrification and denitrification during composting, dairy manure and sugarcane pressmud co-composting with FGDG (CPG) and without FGDG (CP) were conducted in this work. The physico-chemical parameters and the copies of nitrification and denitrification functional genes with real-time quantitative polymerase chain reaction (qPCR) during composting were analyzed. FGDG amendment displayed an inhibitory effect on the copies of 16S rDNA and delayed the occurrence of the highest gene copies of amoA during composting. The nxrA gene copies was inhibited by FGDG amendment during the mature phase. The addition of FGDG increased the relative content of narG and nirS during composting, contributing to more NO3(-)-N being reduced to NO2(-)-N. The amoA showed significant negative correlation with OM and NH4(+)-N, and positive correlation with NO3(-)-N. The nxrA displayed a negative correlation with temperature. These results demonstrated FGDG amendment significantly affected the copies of nitrification and denitrification functional genes, which changed the nitrogen flux of composting. Taken together, these data shed an insight into FGDG amendment affecting the nitrogen transformation during composting on a molecular level. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Reduced turning frequency and delayed poultry manure addition reduces N loss from sugarcane compost.
Bryndum, S; Muschler, R; Nigussie, A; Magid, J; de Neergaard, A
2017-07-01
Composting is an effective method to recycle biodegradable waste as soil amendment in smallholder farming systems. Although all essential plant nutrients are found in compost, a substantial amount of nitrogen is lost during composting. This study therefore investigated the potential of reducing N losses by (i) delaying the addition of nitrogen-rich substrates (i.e. poultry manure), and (ii) reducing the turning frequency during composting. Furthermore, we tested the effect of compost application method on nitrogen mineralization. Sugarcane-waste was composted for 54days with addition of poultry manure at the beginning (i.e. early addition) or after 21days of composting (delayed addition). The compost pile was then turned either every three or nine days. Composts were subsequently applied to soil as (i) homogeneously mixed, or (ii) stratified, and incubated for 28days to test the effect of compost application on nitrogen mineralization. The results showed that delayed addition of poultry manure reduced total nitrogen loss by 33% and increased mineral nitrogen content by >200% compared with early addition. Similarly, less frequent turning reduced total N loss by 12% compared with frequent turning. Stratified placement of compost did not enhance N mineralization compared to a homogeneous mixing. Our results suggested that simple modifications of the composting process (i.e. delayed addition and/or turning frequency) could significantly reduce N losses and improve the plant-nutritional value of compost. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Grewal, Sukhbir K.; Rajeev, Sreekumari; Sreevatsan, Srinand; Michel, Frederick C.
2006-01-01
Livestock manures contain numerous microorganisms which can infect humans and/or animals, such as Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., and Mycobacterium avium subsp. paratuberculosis (Mycobacterium paratuberculosis). The effects of commonly used manure treatments on the persistence of these pathogens have rarely been compared. The objective of this study was to compare the persistence of artificially inoculated M. paratuberculosis, as well as other naturally occurring pathogens, during the treatment of dairy manure under conditions that simulate three commonly used manure management methods: thermophilic composting at 55°C, manure packing at 25°C (or low-temperature composting), and liquid lagoon storage. Straw and sawdust amendments used for composting and packing were also compared. Manure was obtained from a large Ohio free-stall dairy herd and was inoculated with M. paratuberculosis at 106 CFU/g in the final mixes. For compost and pack treatments, this manure was amended with sawdust or straw to provide an optimal moisture content (60%) for composting for 56 days. To simulate liquid storage, water was added to the manure (to simulate liquid flushing and storage) and the slurry was placed in triplicate covered 4-liter Erlenmeyer flasks, incubated under ambient conditions for 175 days. The treatments were sampled on days 0, 3, 7, 14, 28, and 56 for the detection of pathogens. The persistence of M. paratuberculosis was also assessed by a PCR hybridization assay. After 56 days of composting, from 45 to 60% of the carbon in the compost treatments was converted to CO2, while no significant change in carbon content was observed in the liquid slurry. Escherichia coli, Salmonella, and Listeria were all detected in the manure and all of the treatments on day 0. After 3 days of composting at 55°C, none of these organisms were detectable. In liquid manure and pack treatments, some of these microorganisms were detectable up to 28 days. M. paratuberculosis was detected by standard culture only on day 0 in all the treatments, but was undetectable in any treatment at 3 and 7 days. On days 14, 28, and 56, M. paratuberculosis was detected in the liquid storage treatment but remained undetectable in the compost and pack treatments. However, M. paratuberculosis DNA was detectable through day 56 in all treatments and up to day 175 in liquid storage treatments. Taken together, the results indicate that high-temperature composting is more effective than pack storage or liquid storage of manure in reducing these pathogens in dairy manure. Therefore, thermophilic composting is recommended for treatment of manures destined for pathogen-sensitive environments such as those for vegetable production, residential gardening, or application to rapidly draining fields. PMID:16391093
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USDA-ARS?s Scientific Manuscript database
Inhouse composting is a management practice to reduce pathogen in poultry litter. In between flocks, growers windrow the litter inside the broiler houses. This results in high temperatures that can reduce some pathogens in the litter. However, this practice is likely to increase emissions of NH3 and...
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Seng, Bunrith; Kaneko, Hidehiro; Hirayama, Kimiaki; Katayama-Hirayama, Keiko
2012-01-01
This paper presents a mathematical model of vertical water movement and a performance evaluation of the model in static pile composting operated with neither air supply nor turning. The vertical moisture content (MC) model was developed with consideration of evaporation (internal and external evaporation), diffusion (liquid and vapour diffusion) and percolation, whereas additional water from substrate decomposition and irrigation was not taken into account. The evaporation term in the model was established on the basis of reference evaporation of the materials at known temperature, MC and relative humidity of the air. Diffusion of water vapour was estimated as functions of relative humidity and temperature, whereas diffusion of liquid water was empirically obtained from experiment by adopting Fick's law. Percolation was estimated by following Darcy's law. The model was applied to a column of composting wood chips with an initial MC of 60%. The simulation program was run for four weeks with calculation span of 1 s. The simulated results were in reasonably good agreement with the experimental results. Only a top layer (less than 20 cm) had a considerable MC reduction; the deeper layers were comparable to the initial MC, and the bottom layer was higher than the initial MC. This model is a useful tool to estimate the MC profile throughout the composting period, and could be incorporated into biodegradation kinetic simulation of composting.
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Paluszak, Z; Lipowski, A; Ligocka, A
2010-01-01
The effect of composting and anaerobic fermentations under meso- and thermophylic conditions (37 degrees and 55 degrees C) on the survival of bovine parvovirus (BPV) and Aujeszky's disease viruse (ADV) in meat wastes has been examined in this study. Viruses were adsorbed on filters and introduced into carriers which were made of meat fragments of different sizes and bones or in the form of suspension they were introduced into the biomass in the course of processes of waste treatment. Carriers were removed at appropriate time intervals and virus titres were determined. The thermoresistant parvovirus survived for the longest time during mesophylic fermentation (almost 70 days), slightly shorter during composting (7-9.5 days depending on the type of carrier) and for the shortest time--at 55 degrees C (46-76 hours). Its inactivation rate was the fastest in a suspension, slower in meat and bone carriers. ADV inactivation proceeded considerably faster, as compared with BPV. Its active particles were not detected as early as in the 30th minute of thermophylic fermentation, the 6th hour of mesophylic fermentation and at the first sampling time during composting (at the 72nd hour). Total survival time ranged from 50 min to 13 hours. All the tested technologies enabled the effective elimination of ADV and on average twofold decrease in BPV titre. From the study conducted it follows that of both viruses, the BPV should be applied for validation processes of methods used in meat waste processing, particularly if this refers to methods where higher temperature is the factor inactivating pathogens.
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Janczak, Damian; Malińska, Krystyna; Czekała, Wojciech; Cáceres, Rafaela; Lewicki, Andrzej; Dach, Jacek
2017-08-01
Composting of poultry manure which is high in N and dense in structure can cause several problems including significant N losses in the form of NH 3 through volatilization. Biochar due to its recalcitrance and sorption properties can be used in composting as a bulking agent and/or amendment. The addition of a bulking agent to high moisture raw materials can assure optimal moisture content and enough air-filled porosity but not necessarily the C/N ratio. Therefore, amendment of low C/N composting mixtures with biochar at low rates can have a positive effect on composting dynamics. This work aimed at evaluating the effect of selected doses of wood derived biochar amendment (0%, 5% and 10%, wet weight) to poultry manure (P) mixed with wheat straw (S) (in the ratio of 1:0.4 on wet weight) on the total ammonia emissions (including gaseous emissions of ammonia and liquid emissions of ammonium in the collected condensate and leachate) during composting. The process was performed in 165L laboratory scale composting reactors for 42days. The addition of 5% and 10% of biochar reduced gaseous ammonia emission by 30% and 44%, respectively. According to the obtained results, the measure of emission through the condensate would be necessary to assess the impact of the total ammonia emission during the composting process. Copyright © 2017 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Zhong, Jia; Wei, Yuansong; Wan, Hefeng; Wu, Yulong; Zheng, Jiaxi; Han, Shenghui; Zheng, Bofu
2013-12-01
Greenhouse gas (GHG) emissions from animal manure management are of great concern in China. However, there are still great uncertainties about China's GHG inventory due to the GHG emission factors partly used default values from the Intergovernmental Panel of Climate Change (IPCC) guidelines. The purpose of this study was to use a case study in Beijing to determine the regional GHG emission factors based on the combination of swine manure composting and land application of the compost with both on-site examination and a life cycle assessment (LCA). The results showed that the total GHG emission factor was 240 kgCO2eq tDS-1 (dry solids), including the direct GHG emission factor of 115 kgCO2eq tDS-1 for swine manure composting and 48 kgCO2eq tDS-1 for land application of the compost. Among the total GHG emissions of 5.06 kgCH4 tDS-1 and 0.13 kgN2O tDS-1, the swine manure composting contributed approximately 89% to CH4 emissions while land application accounted for 92% of N2O emission. Meanwhile, the GHG emission profile from the full process in Beijing in 2015 and 2020 was predicted by the scenario analysis. The composting and land application is a cost-effective way for animal manure management in China considering GHG emissions.
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The distribution of active β-glucosidase-producing microbial communities in composting.
Zang, Xiangyun; Liu, Meiting; Wang, Han; Fan, Yihong; Zhang, Haichang; Liu, Jiawen; Xing, Enlu; Xu, Xiuhong; Li, Hongtao
2017-12-01
The composting ecosystem is a suitable source for the discovery of novel microorganisms and secondary metabolites. Cellulose degradation is an important part of the global carbon cycle, and β-glucosidases complete the final step of cellulose hydrolysis by converting cellobiose to glucose. This work analyzes the succession of β-glucosidase-producing microbial communities that persist throughout cattle manure - rice straw composting, and evaluates their metabolic activities and community advantage during the various phases of composting. Fungal and bacterial β-glucosidase genes belonging to glycoside hydrolase families 1 and 3 (GH1 and GH3) amplified from DNA were classified and gene abundance levels were analyzed. The major reservoirs of β-glucosidase genes were the fungal phylum Ascomycota and the bacterial phyla Firmicutes, Actinobacteria, Proteobacteria, and Deinococcus-Thermus. This indicates that a diverse microbial community utilizes cellobiose. The succession of dominant bacteria was also detected during composting. Firmicutes was the dominant bacteria in the thermophilic phase of composting; there was a shift to Actinomycetes in the maturing stage. Proteobacteria accounted for the highest proportions during the heating and thermophilic phases of composting. By contrast, the fungal phylum Ascomycota was a minor microbial community constituent in thermophilic phase of composting. Combined with the analysis of the temperature, cellulose degradation rate and the carboxymethyl cellulase and β-glucosidase activities showed that the bacterial GH1 family β-glucosidase genes make greater contribution in cellulose degradation at the later thermophilic stage of composting. In summary, even GH1 bacteria families β-glucosidase genes showing low abundance in DNA may be functionally important in the later thermophilic phase of composting. The results indicate that a complex community of bacteria and fungi expresses β-glucosidases in compost. Several β-glucosidase-producing bacteria and fungi identified in this study may represent potential indicators of composting in cellulose degradation.
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Compost made of organic wastes suppresses fusariosis
NASA Astrophysics Data System (ADS)
Kuryntseva, Polina; Galitskaya, Polina; Biktasheva, Liliya; Selivanovkaya, Svetlana
2017-04-01
Fungal plant diseases cause dramatic yield losses worldwide. Usually, pesticides are used for soil sanitation, and it results in practically pest-free soils, although pesticides cause a biological vacuum, which present many horticultural disadvantages. Suppressive composts, which possess both fertilizing properties for plants and inhibiting properties for plant pathogens, represent an effective and environmentally friendly alternative to conventional pesticides. In this study, composts obtained from agricultural organic wastes were applied to suppress Fusarium oxysporum of tomato plants in model experiments. Composts were made of mixtures of the widespread organic wastes sampled in Tatarstan (Russia): straw (SW), corn wastes (CW), chicken manure (ChM), cattle manure (CM) and swine manure (SM). 11 two- and three-component mixtures were prepared to obtain the optimal carbon-nitrogen, moisture and pH balances, and composted for 210 days. It was found that the thermophilic phase of composting in all the mixtures lasted from 2 to 35 days, and was characterized by significant fluctuations in temperature, i.e. from 27°C to 59°C. In the initial mixtures, the dissolved organic carbon (DOC) content was between 10 and 62 mg kg-1; it fell significantly on day 13, and then continuously decreased up to day 102, and subsequently remained low. For all the mixtures, maximal respiration activity was observed in the beginning of composting (231.9 mg CO2-C g-1 day-1). After 23 days, this parameter decreased significantly, and fluctuations subsided. The phytotoxicity of the initial compost mixtures varied from 18% (SW+SM) to 100% (CW+ChM+SM, CW+ChM); however, the trends in the dynamics were similar. After 120 days of composting, 5 of 11 samples were not phytotoxic. After 120 days of composting, each mixture was divided into two parts; one was inoculated with a biopreparation consisting of four microbial strains (Trichoderma asperellum, Pseudomonas putida, Pseudomonas fluorescens and Streptomyces spp.), and the other part was not inoculated. Both parts were composted under equivalent conditions. Inoculation led to a slightly shorter period of increasing DOC and respiration activity. It did not influence the temperature profile and phytotoxicity of the mixtures. In contrast, the suppressiveness of the composts towards Fusarium oxysporum increased by 1.2-fold after 60 days, although the inoculated compost mixtures became suppressive 30-58 days earlier. The compost mixture prepared from CM, ChM and CW was the most suppressive one, both in its inoculated and non-inoculated variants. It was therefore used in further experiments. Further, we were searching for the optimal doses of CM+ChM+CW compost's amendments. Amoung several does checked (1%, 5%, 10%, 15%, 20% and 25%), a dose of 20% was demonstrated to be the most effective and resulted in disease suppression of 84% after 21 day of plant incubation. From the three amendment schemes investigated (1 - once before vegetation season, 2 - twice before vegetation season with one month break between amendments, half of the dose each time, 3 - twice, once before winter frost simulation, once before vegetation season, half of the dose each time), the first scheme was the most efficient one. After a single amendment with 20% of compost, soils were suppressive during two consecutive vegetation periods.
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Chao, Lei; Zhou, Qi-xing; Cui, Shuang; Chen, Su; Ren, Li-ping
2007-06-01
This paper studied the profile distribution of heavy metals in soils under different kind livestock feces composts. The results showed that in the process of livestock feces composting, the pH value and organic matter content of soil under feces compost increased significantly, and had a decreased distribution with soil depth. The contents of soil Zn and Cd also had an obvious increase, and decreased with increasing soil depth. Under the composts of chicken and pig feces, soil Cu content decreased with soil depth, while under cattle feces compost, it had little change. Soil Cd and Zn had a stronger mobility than soil Cu, and the Zn, Cd and Cu contents in some soil layers exceeded the first level of the environmental quality standard for soils in China. The geo-accumulation indices showed that only the 0-10 cm soil layer under chicken feces compost and the 0-40 cm soil layer under egg chicken feces compost were lightly polluted by Zn, while the soil profiles under other kinds of livestock feces compost were not polluted by Pb, Cu, Zn and Cd.
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Kaboré, Théodore Wind-Tinbnoma; Houot, Sabine; Hien, Edmond; Zombré, Prosper; Hien, Victor; Masse, Dominique
2010-02-01
The effect of raw materials and their proportions in initial mixtures on organic matter (OM) stabilization and nitrogen (N) availability during pit composting in Sub-Saharan Africa was assessed using biochemical fractionation and laboratory incubations to characterize composts sampled throughout the composting process. Stabilization of OM occurred more rapidly in mixtures with slaughter-house wastes, it was progressive in mixture with household refuses while tree leaves compost remained unstable. Carbon mineralization from compost samples was positively correlated to water soluble and hemicellulose-like organic fractions. Mixtures containing large proportions of household refuses reached the highest stability and total N but available N remained weak. Slaughter-house wastes in the initial mixtures made possible to reach good OM stabilization and the largest N availability. The nature of initial mixing influenced composting parameters, OM stabilization and N availability. It is suggested mixing household refuses and slaughter-house wastes with tree leaves to reach better amending and fertilizer qualities of composts.
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Production of oil palm empty fruit bunch compost for ornamental plant cultivation
NASA Astrophysics Data System (ADS)
Trisakti, B.; Mhardela, P.; Husaini, T.; Irvan; Daimon, H.
2018-02-01
The aim of this research was to produce the oil palm empty fruit bunch (EFB) compost for ornamental plant cultivation. EFB compost was produced by chopping fresh EFB into 1-3 cm pieces, inserting the pieces into basket composter (33 cm W × 28 cm L × 40 cm H), and adding activated liquid organic fertilizer (ALOF) until moisture content (MC) in the range of 55-65%. During composting, the compost pile was turned every 3 days and the MC was maintained at 55-65% range by adding the ALOF. The compost processed was then mixed with sand and rice husk with a ratio of 1:1:1; 1:3:1; 1:0:1 and was used as a potting medium for planting some valuable ornamental plants i.e. cactus (cactaceae), sansevieria, and anthurium. Composting was carried out for 40 days and the compost characteristic were pH 9.0; MC 52.59%; WHC 76%; CN ratio 12.15; N 1.96%; P 0.58%; and K 0.95%. The compost-sand-husk rice mixture can be used as a growing medium where the best ratio for cactus, sansevieria, and anthurium was 1:3:1; 1:1:1; and 1:0:1, respectively.
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Galitskaya, Polina; Biktasheva, Liliya; Saveliev, Anatoly; Grigoryeva, Tatiana; Boulygina, Eugenia; Selivanovskaya, Svetlana
2017-01-01
Composting is viewed as one of the primary methods to treat organic wastes. Co-composting may improve the efficiency of this treatment by establishing the most suitable conditions for decomposers than those present in the individual wastes. Given that bacteria and fungi are the driving agents of composting, information about the composition of their communities and dynamics during composting may improve reproducibility, performance and quality of the final compost as well as help to evaluate the potential human health risk and the choice of the most appropriate application procedure. In this study, the co-composting of mixtures containing two similar components (organic fraction of municipal solid waste and sawdust polluted by oil) and one discriminate component (sewage sludges of different origin) were investigated. Bacterial and fungal community successions in the two mixtures were analyzed during the composting process by determining the change in their structural dynamics using qPCR and 454 pyrosequencing methods in a lab experiment for a period of 270 days. During the initial composting stage, the number of 16S bacterial copies was (3.0±0.2) x 106 and (0.4±0.0) x 107 g-1, and the Rhodospiralles and Lactobacialles orders dominated. Fungal communities had (2.9±0.0) x105 and (6.1±0.2) x105 ITS copies g-1, and the Saccharomycetales order dominated. At the end of the thermophilic stage on the 30th day of composting, bacterial and fungal communities underwent significant changes: dominants changed and their relative abundance decreased. Typical compost residents included Flavobacteriales, Chitinophagaceae and Bacterioidetes for bacteria and Microascaceae, Dothideomycetes, Eurotiomycetes, Sordariomycetes, and Agaricomycetes for fungi. During the later composting stages, the dominating taxa of both bacterial and fungal communities remained, while their relative abundance decreased. In accordance with the change in the dominating OTUs, it was concluded that the dynamics of the bacterial and fungal communities were not similar. Analysis by non-metric multidimensional scaling (NMDS) revealed that the bacterial communities of the two composts became progressively more similar; a similar trend was followed by the fungal community.
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Galitskaya, Polina; Saveliev, Anatoly; Grigoryeva, Tatiana; Boulygina, Eugenia; Selivanovskaya, Svetlana
2017-01-01
Composting is viewed as one of the primary methods to treat organic wastes. Co-composting may improve the efficiency of this treatment by establishing the most suitable conditions for decomposers than those present in the individual wastes. Given that bacteria and fungi are the driving agents of composting, information about the composition of their communities and dynamics during composting may improve reproducibility, performance and quality of the final compost as well as help to evaluate the potential human health risk and the choice of the most appropriate application procedure. In this study, the co-composting of mixtures containing two similar components (organic fraction of municipal solid waste and sawdust polluted by oil) and one discriminate component (sewage sludges of different origin) were investigated. Bacterial and fungal community successions in the two mixtures were analyzed during the composting process by determining the change in their structural dynamics using qPCR and 454 pyrosequencing methods in a lab experiment for a period of 270 days. During the initial composting stage, the number of 16S bacterial copies was (3.0±0.2) x 106 and (0.4±0.0) x 107 g-1, and the Rhodospiralles and Lactobacialles orders dominated. Fungal communities had (2.9±0.0) x105 and (6.1±0.2) x105 ITS copies g-1, and the Saccharomycetales order dominated. At the end of the thermophilic stage on the 30th day of composting, bacterial and fungal communities underwent significant changes: dominants changed and their relative abundance decreased. Typical compost residents included Flavobacteriales, Chitinophagaceae and Bacterioidetes for bacteria and Microascaceae, Dothideomycetes, Eurotiomycetes, Sordariomycetes, and Agaricomycetes for fungi. During the later composting stages, the dominating taxa of both bacterial and fungal communities remained, while their relative abundance decreased. In accordance with the change in the dominating OTUs, it was concluded that the dynamics of the bacterial and fungal communities were not similar. Analysis by non-metric multidimensional scaling (NMDS) revealed that the bacterial communities of the two composts became progressively more similar; a similar trend was followed by the fungal community. PMID:29059245
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Application of compost for effective bioremediation of organic contaminants and pollutants in soil.
Kästner, Matthias; Miltner, Anja
2016-04-01
Soils contaminated with hazardous chemicals worldwide are awaiting remediation activities; bioremediation is often considered as a cost-effective remediation approach. Potential bioapproaches are biostimulation, e.g. by addition of nutrients, fertiliser and organic substrates, and bioaugmentation by addition of compound-degrading microbes or of organic amendments containing active microorganisms, e.g. activated sludge or compost. In most contaminated soils, the abundance of the intrinsic metabolic potential is too low to be improved by biostimulation alone, since the physical and chemical conditions in these soils are not conducive to biodegradation. In the last few decades, compost or farmyard manure addition as well as composting with various organic supplements have been found to be very efficient for soil bioremediation. In the present minireview, we provide an overview of the composting and compost addition approaches as 'stimulants' of natural attenuation. Laboratory degradation experiments are often biased either by not considering the abiotic factors or by focusing solely on the elimination of the chemicals without taking the biotic factors and processes into account. Therefore, we first systemise the concepts of composting and compost addition, then summarise the relevant physical, chemical and biotic factors and mechanisms for improved contaminant degradation triggered by compost addition. These factors and mechanisms are of particular interest, since they are more relevant and easier to determine than the composition of the degrading community, which is also addressed in this review. Due to the mostly empirical knowledge and the nonstandardised biowaste or compost materials, the field use of these approaches is highly challenging, but also promising. Based on the huge metabolic diversity of microorganisms developing during the composting processes, a highly complex metabolic diversity is established as a 'metabolic memory' within developing and mature compost materials. Compost addition can thus be considered as a 'super-bioaugmentation' with a complex natural mixture of degrading microorganisms, combined with a 'biostimulation' by nutrient containing readily to hardly degradable organic substrates. It also improves the abiotic soil conditions, thus enhancing microbial activity in general. Finally, this minireview also aims at guiding potential users towards full exploitation of the potentials of this approach.
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Soil bioassays as tools for sludge compost quality assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Domene, Xavier, E-mail: x.domene@creaf.uab.es; Sola, Laura; Ramirez, Wilson
2011-03-15
Composting is a waste management technology that is becoming more widespread as a response to the increasing production of sewage sludge and the pressure for its reuse in soil. In this study, different bioassays (plant germination, earthworm survival, biomass and reproduction, and collembolan survival and reproduction) were assessed for their usefulness in the compost quality assessment. Compost samples, from two different composting plants, were taken along the composting process, which were characterized and submitted to bioassays (plant germination and collembolan and earthworm performance). Results from our study indicate that the noxious effects of some of the compost samples observed inmore » bioassays are related to the low organic matter stability of composts and the enhanced release of decomposition endproducts, with the exception of earthworms, which are favored. Plant germination and collembolan reproduction inhibition was generally associated with uncomposted sludge, while earthworm total biomass and reproduction were enhanced by these materials. On the other hand, earthworm and collembolan survival were unaffected by the degree of composting of the wastes. However, this pattern was clear in one of the composting procedures assessed, but less in the other, where the release of decomposition endproducts was lower due to its higher stability, indicating the sensitivity and usefulness of bioassays for the quality assessment of composts.« less
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Optimization of waste combinations during in-vessel composting of agricultural waste.
Varma, V Sudharsan; Kalamdhad, Ajay S; Kumar, Bimlesh
2017-01-01
In-vessel composting of agricultural waste is a well-described approach for stabilization of compost within a short time period. Although composting studies have shown the different combinations of waste materials for producing good quality compost, studies of the particular ratio of the waste materials in the mix are still limited. In the present study, composting was conducted with a combination of vegetable waste, cow dung, sawdust and dry leaves using a 550 L rotary drum composter. Application of a radial basis functional neural network was used to simulate the composting process. The model utilizes physico-chemical parameters with different waste materials as input variables and three output variables: volatile solids, soluble biochemical oxygen demand and carbon dioxide evolution. For the selected model, the coefficient of determination reached the high value of 0.997. The complicated interaction of agricultural waste components during composting makes it a nonlinear problem so it is difficult to find the optimal waste combinations for producing quality compost. Optimization of a trained radial basis functional model has yielded the optimal proportion as 62 kg, 17 kg and 9 kg for vegetable waste, cow dung and sawdust, respectively. The results showed that the predictive radial basis functional model described for drum composting of agricultural waste was well suited for organic matter degradation and can be successfully applied.
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Effect of composting on the fate of steroids in beef cattle manure.
Bartelt-Hunt, Shannon L; Devivo, Shannon; Johnson, Leslie; Snow, Daniel D; Kranz, William L; Mader, Terry L; Shapiro, Charles A; van Donk, Simon J; Shelton, David P; Tarkalson, David D; Zhang, Tian C
2013-07-01
In this study, the fate of steroid hormones in beef cattle manure composting is evaluated. The fate of 16 steroids and metabolites was evaluated in composted manure from beef cattle administered growth promotants and from beef cattle with no steroid hormone implants. The fate of estrogens (primary detected as estrone), androgens, progesterone, and the fusarium metabolite and implant α-zearalanol was monitored in manure compost piles. First-order decay rates were calculated for steroid half-lives in compost and ranged from 8 d for androsterone to 69 d for 4-androstenedione. Other steroid concentration data could not be fit to first-order decay models, which may indicate that microbial processes may result in steroid production or synthesis in composting systems. We demonstrate that composting is an effective strategy to remove steroid hormones from manure. Total steroid hormone removal in composted beef cattle manure ranged from 79 to 87%. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
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Degradation of aldrin and endosulfan in rotary drum and windrow composting.
Ali, Muntjeer; Gani, Khalid M; Kazmi, Absar A; Ahmed, Naseem
2016-01-01
Removal efficiencies, kinetics and degradation pathways of aldrin, endosulfan α and endosulfan β in vegetable waste were evaluated during rotary drum and conventional windrow composting. The highest percentage removal of aldrin, endosulfan α and endosulfan β in rotary drum composting was 86.8, 83.3 and 85.3% respectively, whereas in windrow composting, it was 66.6%, 77.7% and 67.2% respectively. The rate constant of degradation of aldrin, endosulfan α and endosulfan β during rotary drum composting ranged from 0.410-0.778, 0.057-0.076 and 0.009-0.061 day(-1) respectively. The pathways of degradation of these pesticides in composting process were proposed. Metabolites dieldrin and 1 hydroxychlorodene formed during composting of aldrin in the vegetable waste indicated the occurrence of epoxidation reaction and oxidation of bridge carbon of aldrin containing the methylene group. Formation of chloroendic acid and chloroendic anhydride during composting of endosulfan containing vegetable waste support the occurrence of endosulfan sulfate and dehydration reaction respectively.
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The Early Years: Composting with Children
ERIC Educational Resources Information Center
Ashbrook, Peggy
2016-01-01
"Composting" is a way to purposefully use the process of decay to break down organic materials in a location where the resulting mixture can be harvested for enriching garden soil. The large body of literature about the science of composting provides many options for early childhood educators to choose from to incorporate into their…
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Modeling of carbon and nitrogen gaseous emissions from cattle manure compost windrows
USDA-ARS?s Scientific Manuscript database
Windrow composting of cattle manure is a significant source of gaseous emissions, which include ammonia (NH3) and the greenhouse gases (GHGs) of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). A manure compost model was developed to simulate carbon (C) and nitrogen (N) processes includ...
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Sadef, Yumna; Poulsen, Tjalfe Gorm; Bester, Kai
2015-06-01
Knowledge about the effects of oxygen concentration, nutrient availability and moisture content on removal of organic micro-pollutants during aerobic composting is at present very limited. Impact of oxygen concentration, readily available nitrogen content (NH4(+), NO3(-)), and moisture content on biological transformation of 15 key organic micro-pollutants during composting, was therefore investigated using bench-scale degradation experiments based on non-sterile compost samples, collected at full-scale composting facilities. In addition, the adequacy of bench-scale composting experiments for representing full-scale composting conditions, was investigated using micro-pollutant concentration measurements from both bench- and full-scale composting experiments. Results showed that lack of oxygen generally prevented transformation of organic micro-pollutants. Increasing readily available nitrogen content from about 50 mg N per 100 g compost to about 140 mg N per 100 g compost actually reduced micro-pollutant transformation, while changes in compost moisture content from 50% to 20% by weight, only had minor influence on micro-pollutant transformation. First-order micro-pollutant degradation rates for 13 organic micro-pollutants were calculated using data from both full- and bench-scale experiments. First-order degradation coefficients for both types of experiments were similar and ranged from 0.02 to 0.03 d(-1) on average, indicating that if a proper sampling strategy is employed, bench-scale experiments can be used to represent full-scale composting conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.
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López, R; Cabeza, I O; Giráldez, I; Díaz, M J
2011-09-01
The concentration of volatile organic compounds (VOCs) during the composting of kitchen waste and pruning residues, and the abatement of VOCs by different compost biofilters was studied. VOCs removal efficiencies greater than 90% were obtained using composts of municipal solid waste (MSW) or MSW-pruning residue as biofilter material. An electronic nose identified qualitative differences among the biofilter output gases at very low concentrations of VOCs. These differences were related to compost constituents, compost particle size (2-7 or 7-20mm), and a combination of both factors. The total concentration of VOCs determined by a photoionization analyser and inferred from electronic nose data sets were correlated over an ample range of concentrations of VOCs, showing that these techniques could be specially adapted for the monitoring of these processes. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Jiang, Jishao; Huang, Yimei; Liu, Xueling; Huang, Hua
2014-09-01
The effects of additives such as apple pomace, bentonite and calcium superphosphate on swine manure composting were investigated in a self-built aerated static box (90 L) by assessing their influences on the transformation of nitrogen, carbon, phosphorous and compost maturity. The results showed that additives all prolonged the thermophilic stage in composting compared to control. Nitrogen losses amounted to 34-58% of the initial nitrogen, in which ammonia volatilization accounted for 0.3-4.6%. Calcium superphosphate was helpful in facilitating composting process as it significantly reduced the ammonia volatilization during thermophilic stage and increased the contents of total nitrogen and phosphorous in compost, but bentonite increased the ammonia volatilization and reduced the total nitrogen concentration. It suggested that calcium superphosphate is an effective additive for keeping nitrogen during swine manure composting. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Hagemann, Nikolas; Subdiaga, Edisson; Orsetti, Silvia; de la Rosa, José María; Knicker, Heike; Schmidt, Hans-Peter; Kappler, Andreas; Behrens, Sebastian
2018-02-01
Biochar, a material defined as charred organic matter applied in agriculture, is suggested as a beneficial additive and bulking agent in composting. Biochar addition to the composting feedstock was shown to reduce greenhouse gas emissions and nutrient leaching during the composting process, and to result in a fertilizer and plant growth medium that is superior to non-amended composts. However, the impact of biochar on the quality and carbon speciation of the organic matter in bulk compost has so far not been the focus of systematic analyses, although these parameters are key to determine the long-term stability and carbon sequestration potential of biochar-amended composts in soil. In this study, we used different spectroscopic techniques to compare the organic carbon speciation of manure compost amended with three different biochars. A non-biochar-amended compost served as control. Based on Fourier-transformed infrared (FTIR) and 13 C nuclear magnetic resonance (NMR) spectroscopy we did not observe any differences in carbon speciation of the bulk compost independent of biochar type, despite a change in the FTIR absorbance ratio 2925cm -1 /1034cm -1 , that is suggested as an indicator for compost maturity. Specific UV absorbance (SUVA) and emission-excitation matrixes (EEM) revealed minor differences in the extractable carbon fractions, which only accounted for ~2-3% of total organic carbon. Increased total organic carbon content of biochar-amended composts was only due to the addition of biochar-C and not enhanced preservation of compost feedstock-C. Our results suggest that biochars do not alter the carbon speciation in compost organic matter under conditions optimized for aerobic decomposition of compost feedstock. Considering the effects of biochar on compost nutrient retention, mitigation of greenhouse gas emissions and carbon sequestration, biochar addition during aerobic composting of manure might be an attractive strategy to produce a sustainable, slow release fertilizer. Copyright © 2017 Elsevier B.V. All rights reserved.
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Alavi, Nadali; Daneshpajou, Monavvar; Shirmardi, Mohammad; Goudarzi, Gholamreza; Neisi, Abdolkazem; Babaei, Ali Akbar
2017-11-01
Fermentation of ethanol as a product of sugarcane agro-industry causes the discharge of large amounts of a liquid waste called vinasse into the environment. In this study, co-composting followed by vermicomposting process of the mixtures of vinasse, cow manure, and chopped bagasse was performed for 60days using earthworms of Eisenia fetida species. The results showed that the trend of changes in C/N was decreasing. The pH of the final fertilizer was in alkaline range (8.1-8.4). The total potassium decreased during the process, ranging from 0.062 to 0.15%, while the total phosphorus increased and its values ranged from 0.06 to 0.10%. The germination index (GI) for all samples was 100%, while the cellular respiration maturity index was<2mg C-CO 2 g -1 organic carbon day -1 , confirming a very stable compost. The results of this study indicate that the compost obtained from the co-composting-vermicomposting process could be used as a sound soil amendment. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Amir, Soumia; Benlboukht, Fatima; Cancian, Nadia; Winterton, Peter; Hafidi, Mohamed
2008-12-30
In Marrakech, solid by-products from tanneries are highly polluting, generating large amounts of nitrogenous and organic matter. In the present study composting is tested as a cost-effective method for waste management to overcome many of the environmental hazards and produce a stable, rich material for soil fertilization. Two composting trials were conducted after neutralization by ammonia or lime. The aim of the neutralization was to avoid the antimicrobial effects of the acidity in the tannery waste, thus ensuring correct composting. Different techniques such as elemental analysis and 13C NMR spectroscopy were applied to analyse humic acids isolated from raw and composted materials, and to monitor the process of tannery waste composting, and the stability and maturity of the final product according to the means of neutralization. Comparison of data showed similar behaviour in both trials, but the composting process appeared to be more complete following neutralization with lime. The C, H and N content decreased, while the O increased. The FTIR and 13C NMR spectra show the decrease of aliphatic compounds demonstrated by the reduction of absorbance around 2922cm(-1) and of the resonance in the C-alkyl area around 0-55ppm. The humic acids newly formed during composting were richer in the O-N alkyl and oxidized aromatic structures that increased almost twofold on composting after neutralization with lime. The first principal component axis PC1 (54%) separated C-aliphatic, C-carboxylic and other less stable and less polycondensed compounds such as polyphenols from the more polycondensed O-N alkyl and oxidized C-aromatic compounds.
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Ali, Muntjeer; Kazmi, A A; Ahmed, Naseem
2014-05-01
Study focused on effects of temperature, moisture and pH on degradation and degradation kinetics of aldrin, endosulfan (α), endosulfan (β) and lindane during vegetable waste composting using full-scale continuous rotary drum composter (FSCRDC). Extraction, concentration and quantification of pesticides were made from waste material at different stages by ultra-sonification, silica gel column and GC-MS analysis. Removal efficiency of aldrin, endosulfan α, endosulfan β and lindane was found 85.67%, 84.95%, 83.20% and 81.36% respectively due to optimum temperature, moisture, pH and enhanced microbial activity. Maximum temperature in inlet zone was found 60-65°C which is most suitable for complex microbial population. After feeding and turning in inlet zone, temperature reduced to 38°C from 60 to 65°C and regained it within 7-8h, and pH reduced to 5.3±0.2 from 7.5±0.3 in 4h and regained it in 10h. Heterotrophic bacteria Bacillus sp., Pseudomonas sp. and Lactobacillus sp. also decreased from 4.4×10(3) to 7.80×10(2)CFU g(-1) in 2 h due to gradual variation in temperature and pH. No significant temperature change was found in middle and outlet zones during feeding and turning. Degradation of pesticides was observed as first order kinetics and half-life of aldrin, endosulfan α, endosulfan β and lindane was reduced to 25.54, 18.43, 18.43 and 27.43 d from 1095, 60, 270 and 160 d respectively. Thus, the observations in contrast of removal and degradation kinetics of organochlorine pesticides residues in vegetable waste though full-scale rotary drum composting proved it the best suited technique. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Gutiérrez, M C; Siles, J A; Diz, J; Chica, A F; Martín, M A
2017-01-01
The composting process of six different compostable substrates and one of these with the addition of bacterial inoculums carried out in a dynamic respirometer was evaluated. Despite the heterogeneity of the compostable substrates, cumulative oxygen demand (OD, mgO 2 kgVS) was fitted adequately to an exponential regression growing until reaching a maximum in all cases. According to the kinetic constant of the reaction (K) values obtained, the wastes that degraded more slowly were those containing lignocellulosic material (green wastes) or less biodegradable wastes (sewage sludge). The odor emissions generated during the composting processes were also fitted in all cases to a Gaussian regression with R 2 values within the range 0.8-0.9. The model was validated representing real odor concentration near the maximum value against predicted odor concentration of each substrate, (R 2 =0.9314; 95% prediction interval). The variables of maximum odor concentration (ou E /m 3 ) and the time (h) at which the maximum was reached were also evaluated statistically using ANOVA and a post-hoc Tukey test taking the substrate as a factor, which allowed homogeneous groups to be obtained according to one or both of these variables. The maximum oxygen consumption rate or organic matter degradation during composting was directly related to the maximum odor emission generation rate (R 2 =0.9024, 95% confidence interval) when only the organic wastes with a low content in lignocellulosic materials and no inoculated waste (HRIO) were considered. Finally, the composting of OFMSW would produce a higher odor impact than the other substrates if this process was carried out without odor control or open systems. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Characterization of Explosives Processing Waste Decomposition Due to Composting. Phase 2
1992-11-01
with Ceriodaphnia (10 replicates, each containing 15 mL of test solution and one neonate ). In each temporal block of tests, Ceriodsnhnia survival and... neonate per replicate). This reference validated the biological quality of the dilution water, the Ceriodaphnia food, the test conditions (e.g...incubation temperature and photoperiod), and the health of the neonates used to initiate the tests. Information about the leachates, including the
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Li, Shuyan; Li, Danyang; Li, Jijin; Li, Guoxue; Zhang, Bangxi
2017-12-01
Sewage sludge and corn stalk were co-composted under different aeration rates 0.12 (AR0.12), 0.24 (AR0.24), 0.36 (AR0.36)L·kg -1 DMmin -1 , respectively. Transformation of humic substance was evaluated by a series of chemical and spectroscopic methods to reveal compost humification. Results showed that aeration rate could significantly affect compost stability and humification process. Humic acid contents in AR0.24 were significantly higher than those in the other two treatments. The final humic acid/fulvic acid ratios in AR0.12, AR0.24 and AR0.36 treatment were 1.0, 1.9 and 0.8, respectively, corresponding to the final E 4 /E 6 of 4.7, 3.2 and 5.5. Moreover, compost in AR0.24 treatment had a high stability degree due to the low C/N atom ratio and high C/H atom ratio. However, it is noteworthy that composting could not significantly affect the structure of HA in a 35-day period. These results indicate that composting with the aeration rate of 0.24L·kg -1 DMmin -1 could accelerated the humification process. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Khan, Naser; Clark, Ian; Sánchez-Monedero, Miguel A; Shea, Syd; Meier, Sebastian; Qi, Fangjie; Kookana, Rai S; Bolan, Nanthi
2016-01-01
Two experiments were conducted where three biochars, made from macadamia nutshell (MS), hardwood shaving (WS) and chicken litter (CL), were co-composted with chicken manure and sawdust, and also incubated with a chicken litter based commercial compost. Biochars were added at the rates of 5% and 10% in the co-composting and 10% and 20% in the incubation experiment. The rates of biochar had no consistent effect on the change in element contents of composted- or incubated-biochars. The biochar C demonstrated recalcitrance in both composting and incubation systems. Composting increased the CEC of biochars probably due to thermophilic oxidation. The increases in CEC of WS and CL were 6.5 and 2.2 times, respectively, for composting. Translocation of elements, between biochar and compost medium, occurred in both directions. In most cases, biochars gained elements under the influence of positive difference of concentrations (i.e., when compost medium had higher concentration of elements than biochar), while in some cases they lost elements despite a positive difference. Biochar lost some elements (WS: B; CL: B, Mg and S) under the influence of negative difference of concentrations. Some biochars showed strong affinity for B, C, N and S: the concentration of these elements gained by biochars surpassed the concentration in the respective composting medium. The material difference in the biochars did not have influence on N retention: all three netbag-biochars increased their N content. The cost of production of biochar-compost will be lower in co-composting than incubation, which involves two separate processes, i.e., composting and subsequent incubation. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Biofiltration of isopentane in peat and compost packed beds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Z.; Govind, R.
1997-05-01
Commercially available biofiltration systems have used natural bioactive materials in packed beds due to low media cost and easy availability. Detailed understanding and modeling of biofiltration systems are lacking in existing literature. Experimental studies on the isopentane treatment in air using peat- and compost-packed beds were conducted with inlet isopentane concentrations of 360 to 960 ppmv, and empty-bed gas-phase residence times of 2 to 10 min. High removal efficiencies (>90%) were achieved at low contaminant concentrations (<500 ppmv) and large empty-bed gas-phase residence times (>8 min). For both peat and compost biofilters, there was an optimal water content that gavemore » the highest removal efficiency. For higher water content, mass transfer of isopentane through the liquid phase controlled the biofiltration removal efficiency. At low water content, irreversible changes in the bioactivity of peat and compost occurred, resulting in an irrecoverable loss of removal efficiency. Increases in biofilter bed temperature from 25 to 40 C improved the removal efficiency. A mathematical model incorporating the effect of water content and temperature was developed to describe the packed-bed biofilter performance. Model predictions agreed closely with experimental data.« less
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Evangelou, Alexandros; Gerassimidou, Spyridoula; Mavrakis, Nikitas; Komilis, Dimitrios
2016-05-01
Objective of the work was to monitor two full-scale commingled municipal solid waste (MSW) mechanical and biological pretreatment (MBT) facilities in Greece, namely a biodrying and a composting facility. Monitoring data from a 1.5-year sampling period is presented, whilst microbial respiration indices were used to monitor the decomposition process and the stability status of the wastes in both facilities during the process. Results showed that in the composting facility, the organic matter reduced by 35 % after 8 weeks of combined composting/curing. Material exiting the biocells had a moisture content of less than 30 % (wb) indicating a moisture limitation during the active composting process. The static respiration indexes indicated that some stabilization occurred during the process, but the final material could not be characterized as stable compost. In the biodrying facility, the initial and final moisture contents were 50 % and less than 20 % wb, respectively, and the biodrying index was equal to 4.1 indicating effective biodrying. Lower heating values at the inlet and outlet were approximately 5.5 and 10 MJ/wet kg, respectively. The organic matter was reduced by 20 % during the process and specifically from a range of 63-77 % dw (inlet) to a range of 61-70 % dw. A significant respiration activity reduction was observed for some of the biodrying samples. A statistically significant correlation among all three respiration activity indices was recorded, with the two oxygen related activity indices (CRI7 and SRI24) observing the highest correlation.
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Microbial Abundances Predict Methane and Nitrous Oxide Fluxes from a Windrow Composting System
Li, Shuqing; Song, Lina; Gao, Xiang; Jin, Yaguo; Liu, Shuwei; Shen, Qirong; Zou, Jianwen
2017-01-01
Manure composting is a significant source of atmospheric methane (CH4) and nitrous oxide (N2O) that are two potent greenhouse gases. The CH4 and N2O fluxes are mediated by methanogens and methanotrophs, nitrifying and denitrifying bacteria in composting manure, respectively, while these specific bacterial functional groups may interplay in CH4 and N2O emissions during manure composting. To test the hypothesis that bacterial functional gene abundances regulate greenhouse gas fluxes in windrow composting systems, CH4 and N2O fluxes were simultaneously measured using the chamber method, and molecular techniques were used to quantify the abundances of CH4-related functional genes (mcrA and pmoA genes) and N2O-related functional genes (amoA, narG, nirK, nirS, norB, and nosZ genes). The results indicate that changes in interacting physicochemical parameters in the pile shaped the dynamics of bacterial functional gene abundances. The CH4 and N2O fluxes were correlated with abundances of specific compositional genes in bacterial community. The stepwise regression statistics selected pile temperature, mcrA and NH4+ together as the best predictors for CH4 fluxes, and the model integrating nirK, nosZ with pmoA gene abundances can almost fully explain the dynamics of N2O fluxes over windrow composting. The simulated models were tested against measurements in paddy rice cropping systems, indicating that the models can also be applicable to predicting the response of CH4 and N2O fluxes to elevated atmospheric CO2 concentration and rising temperature. Microbial abundances could be included as indicators in the current carbon and nitrogen biogeochemical models. PMID:28373862
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Fan; Beijing Municipal Research Institute of Environmental Protection, Beijing 100037; Li, Guoxue, E-mail: yangfan19870117@126.com
2015-02-15
Highlights: • Effect of phosphogypsum and superphosphate on composting gas emissions was studied. • The reduction mechanisms of composting gas were clarified in this study. • No negative effect was caused on maturity with phosphogypsum and superphosphate. • CH{sub 4} and NH{sub 3} emission was decreased with phosphogypsum and superphosphate addition. • GHG decreased by 17.4% and 7.3% with phosphogypsum and superphosphate addition. - Abstract: This study investigated the effects of phosphogypsum and superphosphate on the maturity and gaseous emissions of composting kitchen waste. Two amended compost treatments were conducted using phosphogypsum and superphosphate as additives with the addition ofmore » 10% of initial raw materials (dry weight). A control treatment was also studied. The treatments were conducted under aerobic conditions in 60-L reactors for 35 days. Maturity indexes were determined, and continuous measurements of CH{sub 4}, N{sub 2}O, and NH{sub 3} were taken. Phosphogypsum and superphosphate had no negative effects on compost maturity, although superphosphate inhibited the temperature rise in the first few days. The addition of phosphogypsum and superphosphate drastically reduced CH{sub 4} emissions (by 85.8% and 80.5%, respectively) and decreased NH{sub 3} emissions (by 23.5% and 18.9%, respectively). However, a slight increase in N{sub 2}O emissions (by 3.2% and 14.8%, respectively) was observed. Composting with phosphogypsum and superphosphate reduced total greenhouse gas emissions by 17.4% and 7.3% respectively.« less
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USDA-ARS?s Scientific Manuscript database
A study was conducted to determine the effectiveness of composting to breakdown the carcasses of daily poultry mortality and in the process destroy pathogenic microorganisms that may be present. The study was conducted during the summer and repeated in the winter to determine whether the time of yea...
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Li, Yunbei; Li, Weiguang
2015-02-01
Composting is one of the cost-saving ways for sewage sludge treatment to produce a final product that is stable, and free of pathogens and plant seeds. However, the loss of nitrogen through ammonia emission not only reduces the agronomic value of the composting product, but also leads to air pollution and is potentially health threatening. Five mixtures of sewage sludge and acidified sawdust were co-composted for 22 days with different initial pH values (3.51, 4.45, 5.51, 6.48 and 7.56). Acidified sawdust was used as a pH regulator and also bulking agent during composting. Changes in physicochemical properties were characterised by the temperature, organic matter degradation, carbon dioxide emission and pH value. The results showed that regulating the initial pH of composting materials to 5.51~6.48 was the most effective way in reducing ammonia emissions. Compared with the control group, the cumulative ammonia emission was reduced by 52.1% and the nitrogen loss decreased from 44.7% to 24.8% with no adverse effects on organic matter degradation and microbial activity. © The Author(s) 2015.
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Diao, Junshu; Chen, Zhao; Gong, Chao; Jiang, Xiuping
2015-09-01
This study investigated the survival of Escherichia coli O157:H7 and Salmonella Typhimurium in finished dairy compost with different particle sizes during storage as affected by moisture content and temperature under greenhouse conditions. The mixture of E. coli O157:H7 and S. Typhimurium strains was inoculated into the finished composts with moisture contents of 20, 30, and 40%, separately. The finished compost samples were then sieved into 3 different particle sizes (>1000, 500-1000, and <500 μm) and stored under greenhouse conditions. For compost samples with moisture contents of 20 and 30%, the average Salmonella reductions in compost samples with particle sizes of >1000, 500-1000, and <500 μm were 2.15, 2.27, and 2.47 log colony-forming units (CFU) g(-1) within 5 days of storage in summer, respectively, as compared with 1.60, 2.03, and 2.26 log CFU g(-1) in late fall, respectively, and 2.61, 3.33, and 3.67 log CFU g(-1) in winter, respectively. The average E. coli O157:H7 reductions in compost samples with particle sizes of >1000, 500-1000, and <500 μm were 1.98, 2.30, and 2.54 log CFU g(-1) within 5 days of storage in summer, respectively, as compared with 1.70, 2.56, and 2.90 log CFU g(-1) in winter, respectively. Our results revealed that both Salmonella and E. coli O157:H7 in compost samples with larger particle size survived better than those with smaller particle sizes, and the initial rapid moisture loss in compost may contribute to the fast inactivation of pathogens in the finished compost. For the same season, the pathogens in the compost samples with the same particle size survived much better at the initial moisture content of 20% compared to 40%.
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NASA Astrophysics Data System (ADS)
Vergara, S.; Silver, W. L.
2016-12-01
That anthropogenic climate change is irreversible, except in the case of sustained net removal of CO2 from the atmosphere, compels the scientific community to search for terrestrial carbon sinks. The soil is a promising sink: it currently stores more carbon than do the atmosphere and the vegetation combined, and most managed lands are degraded with respect to carbon. The application of compost to rangelands has been shown to enhance carbon uptake by soils, and the production of compost avoids greenhouse gas (GHG) emissions from waste management. Though these two mitigation pathways have been well studied, emissions from the composting process - which should be quantified in order to estimate the net carbon sequestration achieved by applying compost to rangelands - have not. We present a novel approach to quantifying emissions from composting, which we have deployed in Marin County, CA: a micrometerological mass balance set up, using a system of gas and wind towers surrounding a series of composting windrow piles. Real-time greenhouse gas emissions (CO2, N2O, CH4) from the composting waste are measured by a laser spectrometer, and a system of sensors measure conditions within the pile, to identify biogeochemical drivers of those emissions. Understanding these drivers improves our knowledge of the processes governing the production of short-lived climate pollutants, and provides guidance to municipalities and states seeking to minimize their greenhouse gas emissions.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Caricasole, P.; Provenzano, M.R., E-mail: Provenza@agr.uniba.it; Hatcher, P.G.
2011-03-15
In this paper, the evolution of organic matter (OM) during composting of different mixtures of various organic wastes was assessed by means of chemical analyses and CPMAS {sup 13}C NMR spectroscopy measured during composting. The trends of temperatures and C/N ratios supported the correct evolution of the processes. The CPMAS {sup 13}C NMR spectra of all composting substrates indicated a reduction in carbohydrates and an increase in aromatic, phenolic, carboxylic and carbonylic C which suggested a preference by microorganisms for easily degradable C molecules. The presence of hardly degradable pine needles in one of the substrates accounted for the lowestmore » increase in alkyl C and the lowest reduction in carbohydrates and carboxyl C as opposite to another substrate characterized by the presence of a highly degradable material such as spent yeast from beer production, which showed the highest increase of the alkyl C/O-alkyl C ratio. The highest increase of COOH deriving by the oxidative degradation of cellulose was shown by a substrate composed by about 50% of plant residues. The smallest increases in alkyl C/O-alkyl C ratio and in polysaccharides were associated to the degradation of proteins and lipids which are major components of sewage sludge. Results obtained were related to the different composition of fresh organic substrates and provided evidence of different OM evolution patterns as a function of the initial substrate composition.« less
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Khan, Eakalak; Khaodhir, Sutha; Ruangrote, Darin
2009-10-01
Heavy metals are common contaminants in stormwater runoff. One of the devices that can be used to effectively and economically remove heavy metals from runoff is a yard waste compost stormwater filter. The primary goal of composting is to reduce waste volume rather than to produce stormwater filter media. Moisture content (MC) and initial pH, the two important parameters in composting, were studied for their effects on yard waste volume reduction and heavy metal adsorption performances of the compost. The main objective of this investigation was to examine whether the conditions that provided high yard waste volume reduction would also result in compost with good heavy metal removal performances. Manila grass was composted at different initial pHs (5-9) and MCs (30-70%) and the composts were used to adsorb cadmium, copper, lead and zinc from water. Results indicated that MC is more critical than initial pH for both volume reduction and production of compost with high metal adsorption performances. The most optimal conditions for the two attributes were not exactly the same but lower MCs of 30-40% and pH 7 or higher tended to satisfy both high volume reduction and effective metal adsorption.
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Changes in cadmium mobility during composting and after soil application
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanc, Ales; Tlustos, Pavel; Szakova, Jirina
2009-08-15
The effect of twelve weeks of composting on the mobility and bioavailability of cadmium in six composts containing sewage sludge, wood chips and grass was studied, along with the cadmium immobilization capacity of compost. Two different soils were used and Cd accumulation measured in above-ground oat biomass (Avena sativa L.). Increasing pH appears to be an important cause of the observed decreases in available cadmium through the composting process. A pot experiment was performed with two different amounts of compost (9.6 and 28.8 g per kg of soil) added into Fluvisol with total Cd 0.255 mg kg{sup -1}, and contaminatedmore » Cambisol with total Cd 6.16 mg kg{sup -1}. Decrease of extractable Cd (0.01 mol l{sup -1} CaCl{sub 2}) was found in both soils after compost application. The higher amount of compost immobilized an exchangeable portion of Cd (0.11 mol l{sup -1} CH{sub 3}COOH extractable) in contaminated Cambisol unlike in light Fluvisol. The addition of a low amount of compost decreased the content of Cd in associated above-ground oat biomass grown in both soils, while a high amount of compost decreased the Cd content in oats only in the Cambisol.« less
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Tambone, Fulvia; Terruzzi, Laura; Scaglia, Barbara; Adani, Fabrizio
2015-01-01
The aim of this paper was to assess the characteristics of the solid fractions (SF) obtained by mechanical separation of digestate, their compostability and compost quality. To do so, the SF of digestates obtained from anaerobic digestion of pig slurry, energy crops and agro-industrial residues were sampled in five plants located in Northern Italy. Results obtained indicated that anaerobic digestion by itself promoted the high biological stability of biomasses with a Potential Dynamic Respiration Index (PDRI) close to 1000 mgO2 kg V S(-1)h(-1). Subsequent composting of digestates, with an added bulking agent, did not give remarkably different results, and led only to a slight modification of the characteristics of the initial non-composted mixtures; the composts obtained fully respected the legal limits for high quality compost. Chemical studies of organic matter composition of the biomasses by using CP MAS (13)C NMR, indicated that the compost was composed of a high relative content of O-alkyl-C (71.47% of total C) (cellulose and hemicelluloses) and a low alkyl-C (12.42%) (i.e. volatile fatty acids, steroid-like molecules, aliphatic biopolymers and proteins). Copyright © 2014 Elsevier Ltd. All rights reserved.
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Oxygen respirometry to assess stability and maturity of composted municipal solid waste
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iannotti, D.A.; Grebus, M.E.; Toth, B.L.
1994-11-01
The stability and maturity of compost prepared from municipal solid waste (MSW) at a full-scale composting plant was assessed through chemical, physical, and biological assays. Respiration bioassays used to determine stability (O{sub 2} and CO{sub 2} respirometry) were sensitive to process control problems at the composting plant and indicated increasing stability with time. Radish (Raphanus sativus L.) and ryegrass (Lolium perenne L.) growth bioassays revealed that immature compost samples inhibited growth. Growth of ryegrass in potting mix prepared with cured compost not amended with fertilizer was enhanced as compared to a pest control. Garden cress (Lepidium sativum L.) seed germination,more » used as an indicator of phytotoxicity, revealed inhibition of germination at all compost maturity levels. The phytotoxicity was though to be salt-related. Spearman rank-order correlations demonstrated that O{sub 2} respirometry, water-soluble organic C, and the water extract organic C to organic N ratio, significantly correlated with compost age and best indicated an acceptable level of stability. Oxygen respirometry also best predicted the potential for ryegrass growth, and an acceptable level of compost maturity. 31 refs., 4 figs., 5 tabs.« less
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Evaluation of microbially enhanced composting of sophora flavescens residues.
Wang, Hai B; Han, Li R; Feng, Jun T; Zhang, Xing
2016-02-01
The effects of inoculants on the composting of Sophora flavescens residues were evaluated based on several physical, chemical and biological parameters, as well as the infrared spectra. Compared to the control compost without inoculants, the treatment compost with inoculants (Bacillus subtilis strain G-13 and Chaetomium thermophilum strain GF-1) had a significantly longer thermophilic duration, higher cellulase activity and a higher degradation rate of cellulose, hemicellulose and lignin (P < 0.05). Thus, a higher maturity degree of compost with apparently lower C:N ratio (15.88 vs. 17.77) and NH 4 -N:NO 3 -N ratio (0.16 vs. 0.20) was obtained with the inoculation comparing with the control (P < 0.05). Besides, the inoculants could markedly accelerate the composting process and increase the maturity degree of compost as indicated by the germination index (GI) in which the treatment reached the highest GI of 133.2% at day 15 while the control achieved the highest GI of 125.7% at day 30 of the composting. Inoculation with B. subtilis and C. thermophilum is a useful method to enhance the S. flavescens residues composting according to this study.
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Toumpeli, Anna; Pavlatou-Ve, Athina K; Kostopoulou, Sofia K; Mamolos, Andreas P; Siomos, Anastasios S; Kalburtji, Kiriaki L
2013-10-15
Composting organic residues is a friendly to the environment alternative to producing fertilizer. This research was carried out to study the process of composting Phragmites australis Cav. plant material alone or with animal manure on a pilot-scale, to evaluate firstly the quality of the composts produced and secondly, using a pot experiment, the effects of their application on soil physicochemical characteristics and tomato plants development. For the compost production a randomized complete block design was used with five treatments (five compost types) and four replications. For the pot experiment, a completely randomized design was used with 17 treatments (plain soil, soil with synthetic fertilizer and the application of five compost types, at three rates each) and five replications. Compost N increased with composting time, while C/N ratio decreased significantly and by the end it ranged from 43.3 for CM to 22.6 for CY. Compost pH became almost neutral, ranging from 6.73 for CY to 7.21 for CM3Y3AM4 by the end. Compost combinations CY7AM3 and CM7AM3 had a more positive influence on the soil physicochemical characteristics than the others. Soil N, P, Ca and Mg concentrations and the reduction of clay dispersion were the highest when CM7AM3 compost was added. The macro-aggregate stability was the highest for CY7AM3, which also sustained plant growth. The latter compost combination improved most of the soil physicochemical characteristics and plant growth especially, when the application rate was 4% (w/w), which equals to 156 Mg ha(-1). Copyright © 2013 Elsevier Ltd. All rights reserved.
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Decline in extractable antibiotics in manure-based composts during composting.
Kim, K-R; Owens, G; Ok, Y S; Park, W-K; Lee, D B; Kwon, S-I
2012-01-01
A wide variety of antibiotics have been detected in natural water samples and this is of potential concern because of the adverse environmental effects of such antibiotic residues. One of the main sources of antibiotics effluence to the surrounding environment is livestock manures which often contain elevated concentrations of veterinary antibiotics (VAs) which survive digestion in the animal stomach following application in animal husbandry practices. In Korea, livestock manures are normally used for compost production indicating that there is potential for antibiotic release to the environment through compost application to agricultural lands. Therefore, reduction of the amount of VAs in composts is crucial. The purpose of this study was to understand the influence of the composting process and the components of the compost on the levels of three common classes of antibiotics (tetracyclines, sulfonamides, and macrolides). Composted materials at different stages of composting were collected from compost manufacturing plants and the variation in antibiotic concentrations was determined. Three different antibiotics, chlortetracycline (CTC), sulfamethazine (SMZ), and tylosin (TYL) at three different concentrations (2, 10, and 20mgkg(-1)) were also applied to a mixture of pig manure and sawdust and the mixtures incubated using a laboratory scale composting apparatus to monitor the changes in antibiotic concentrations during composting together with the physicochemical properties of the composts. During composting, in both field and lab-scale investigations, the concentrations of all three different antibiotics declined below the relevant Korean guideline values (0.8mgkg(-1) for tetracyclines, 0.2mgkg(-1) for sulfonamides and 1.0mgkg(-1) for macrolides). The decline of tetracycline and sulfonamide concentrations was highly dependent on the presence of sawdust while there was no influence of sawdust on TYL decline. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Yin, Yanan; Gu, Jie; Wang, Xiaojuan; Song, Wen; Zhang, Kaiyu; Sun, Wei; Zhang, Xin; Zhang, Yajun; Li, Haichao
2017-01-01
Copper is one of the most abundant heavy metals present in swine manure. In this study, a laboratory-scale aerobic composting system was amended with Cu at three levels (0, 200, and 2000 mg kg-1, i.e., control, Cu200, and Cu2000 treatments, respectively) to determine its effect on the fate of copper resistance genes [copper resistance genes (CRGs): pcoA, cusA, copA, and tcrB], antibiotic resistance genes [antibiotic resistance genes (ARGs): erm(A) and erm(B)], and intl1. The results showed that the absolute abundances of pcoA, tcrB, erm(A), erm(B), and intl1 were reduced, whereas those of copA and cusA increased after swine manure composting. Redundancy analysis showed that temperature significantly affected the variations in CRGs, ARGs, and intl1. The decreases in CRGs, ARGs, and intI1 were positively correlated with the exchangeable Cu levels. The bacterial community could be grouped according to the composting time under different treatments, where the high concentration of copper had a more persistent effect on the bacterial community. Network analysis determined that the co-occurrence of CRGs, ARGs, and intI1, and the bacterial community were the main contributors to the changes in CRGs, ARG, and intl1. Thus, temperature, copper, and changes in the bacterial community composition had important effects on the variations in CRGs, ARGs, and intl1 during manure composting in the presence of added copper. PMID:28316595
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Impact of composting strategies on the degradation of nonylphenol in sewage sludge.
Zheng, Guodi; Chen, Tongbin; Yu, Jie; Gao, Ding; Shen, Yujun; Niu, Mingjie; Liu, Hongtao
2015-12-01
Nonylphenol can be present in sewage sludge, and this can limit the use of the sewage sludge to amend soil. Composting is one of the most efficient and economical methods of making sewage sludge stable and harmless. The nonylphenol degradation rates during composting with added bulking agents and with aeration applied were studied. Three organic bulking agents (sawdust, corn stalk, and mushroom residue) were added to sewage sludge, and the effects of the bulking agents used and the amount added on nonylphenol degradation were determined. The highest apparent nonylphenol degradation rate (71.6%) was found for sewage sludge containing 20% mushroom residue. The lowest apparent nonylphenol degradation rate (22.5%) was found for sewage sludge containing 20% sawdust. The temperature of the composting pile of sewage sludge containing 20% sawdust became too high for nonylphenol to be efficiently degraded, and the apparent nonylphenol degradation rate was lower than was found for sewage sludge containing 10% sawdust. Increasing the ventilating time from 5 to 15 min increased the apparent nonylphenol degradation rate from 19.7 to 41.6%. Using appropriate aerobic conditions facilitates the degradation of nonylphenol in sewage sludge, decreasing the risks posed by sewage sludge applied to land. Adding too much of a bulking agent can decrease the amount of the nonylphenol degraded. Increasing the ventilating time and the amount of air supplied can increase the amount of nonylphenol degraded even if doing so causes the composting pile temperature to remain low.
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Biogas: Production and utilization
NASA Astrophysics Data System (ADS)
Price, E. C.; Cheremisinoff, P. N.
Among the aspects of biogas production and utilization covered are: (1) the microbiology and biochemistry of the acid and methane production stages in the anaerobic process; (2) factors affecting the process, such as temperature, acidity and alkalinity, nutrients, and cations; (3) denitrification processes and systems; and (4) the process kinetics of suspended growth systems, packed columns, and fluidized beds. Also considered are such issues in the application of this technology as the digestion of municipal treatment plant sludges, animal wastes, food processing wastes and energy crops. Attention is in addition given to anaerobic digester design, offgas measurement of anaerobic digesters, and sludge treatment through soil conditioning and composting.
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Swain, S; Harnik, T; Mejia-Chang, M; Hayden, K; Bakx, W; Creque, J; Garbelotto, M
2006-10-01
To determine the effects of heat and composting treatments on the viability of the plant pathogen Phytophthora ramorum grown on both artificial and various natural substrates. Phytophthora ramorum was grown on V8 agar, inoculated on bay laurel leaves (Umbellularia californica) and on woody tissues of coast live oak (Quercus agrifolia). Effects on growth, viability and survival were measured as a result of treatment in ovens and compost piles. Direct plating onto PARP medium and pear-baiting techniques were used to determine post-treatment viability. No P. ramorum was recovered at the end of the composting process, regardless of the isolation technique used. By using a PCR assay designed to detect the DNA of P. ramorum, we were able to conclude the pathogen was absent from mature compost and not merely suppressed or dormant. Some heat and composting treatments eliminate P. ramorum to lower than detectable levels on all substrates tested. Composting is an effective treatment option for sanitization of P. ramorum-infected plant material. Assaying for pathogen viability in compost requires a direct test capable of differentiating between pathogen suppression and pathogen elimination.
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In-vessel composting of household wastes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iyengar, Srinath R.; Bhave, Prashant P.
The process of composting has been studied using five different types of reactors, each simulating a different condition for the formation of compost; one of which was designed as a dynamic complete-mix type household compost reactor. A lab-scale study was conducted first using the compost accelerators culture (Trichoderma viridae, Trichoderma harzianum, Trichorus spirallis, Aspergillus sp., Paecilomyces fusisporus, Chaetomium globosum) grown on jowar (Sorghum vulgare) grains as the inoculum mixed with cow-dung slurry, and then by using the mulch/compost formed in the respective reactors as the inoculum. The reactors were loaded with raw as well as cooked vegetable waste for amore » period of 4 weeks and then the mulch formed was allowed to maturate. The mulch was analysed at various stages for the compost and other environmental parameters. The compost from the designed aerobic reactor provides good humus to build up a poor physical soil and some basic plant nutrients. This proves to be an efficient, eco-friendly, cost-effective, and nuisance-free solution for the management of household solid wastes.« less
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Changes in carbon fractions during composting and maturation of organic wastes
NASA Astrophysics Data System (ADS)
Garcia, Carlos; Hernandez, Teresa; Costa, Francisco
1991-05-01
Seven mixtures from four organic residues—an aerobic sewage sludge, a city refuse, a peat residue, and a grape debris—were composted, and the changes undergone by their different carbon fractions during their composting and maturation were studied. In most cases a decrease in carbon fractions during the composting and maturation processes was observed. The extractable carbon, however, increased during maturation. Organic matter mineralization was greater in the composts with city refuse than in those with sewage sludge. The samples with peat residue showed the lowest decreases in carbon fractions. During maturation, an increase of humiclike fraction was observed, which was reflected by a decrease in the soluble carbon-precipitated carbon ratio at pH 2. Water-soluble carbon was the carbon fraction most easily degradable by microorganisms, and its amount correlated significantly with composting time in all the samples.
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Composting Assessment for Organic Solid Waste at Fort Polk, Louisiana
2014-04-01
has been some development in biodegradable and compostable replace- ments. Three types dominate: bioplastics, starch -based plastics, and bagasse...temperatures. Bioplastics are, therefore, not used for long-term storage, like drinking water bottles. Starched -based plastics, particularly those...from corn and potato starch , tend to make a weak plastic, usually suitable for light duty items. Lastly, bagasse is a highly fibrous plant material
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Pascon, Renata C.; de Oliveira, Julio Cezar Franco; Digiampietri, Luciano A.; Barbosa, Deibs; Peixoto, Bruno Malveira; Vallim, Marcelo A.; Viana-Niero, Cristina; Ostroski, Eric H.; Telles, Guilherme P.; Dias, Zanoni; da Cruz, João Batista; Juliano, Luiz; Verjovski-Almeida, Sergio; da Silva, Aline Maria; Setubal, João Carlos
2013-01-01
Composting operations are a rich source for prospection of biomass degradation enzymes. We have analyzed the microbiomes of two composting samples collected in a facility inside the São Paulo Zoo Park, in Brazil. All organic waste produced in the park is processed in this facility, at a rate of four tons/day. Total DNA was extracted and sequenced with Roche/454 technology, generating about 3 million reads per sample. To our knowledge this work is the first report of a composting whole-microbial community using high-throughput sequencing and analysis. The phylogenetic profiles of the two microbiomes analyzed are quite different, with a clear dominance of members of the Lactobacillus genus in one of them. We found a general agreement of the distribution of functional categories in the Zoo compost metagenomes compared with seven selected public metagenomes of biomass deconstruction environments, indicating the potential for different bacterial communities to provide alternative mechanisms for the same functional purposes. Our results indicate that biomass degradation in this composting process, including deconstruction of recalcitrant lignocellulose, is fully performed by bacterial enzymes, most likely by members of the Clostridiales and Actinomycetales orders. PMID:23637931
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Nitrous oxide flux from landfill leachate-sawdust nitrogenous compost.
Hui, C H; So, M K; Lee, C M; Chan, G Y S
2003-09-01
Composted nitrogenous waste has the potential to produce excessive amounts of nitrous oxide (N2O), a potent greenhouse gas that also contributes to stratospheric ozone depletion. In this laboratory study, sawdust was irrigated with varying amounts of landfill leachate with high NH4+-N content (3950 mg l(-1)). Physicochemical properties, including the amount of N2O produced, were monitored during the composting process over 28 days. A rapid decline in NH4+-N in the first 4 days and increasing NO3--N for 11 days was followed by lower but stabilized levels of available-N, even with repeated leachate irrigation. Less than 0.03% of the leachate-applied N was lost as N2O. Higher leachate applications as much as tripled N2O production, but this represented a lesser proportion overall of the total nitrogen. Addition of glucose to the composting process had no significant effect on N2O production. The derived sawdust-leachate compost supported healthy growth of Sesbania rostrata. It is concluded that compost can be produced from sawdust irrigated with landfill leachate without substantial emission of N2O, although excessive flux of N2O remains about high application rates over longer time periods.
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Management of MSW in Spain and recovery of packaging steel scrap.
Tayibi, Hanan; Peña, Carmen; López, Félix A; López-Delgado, Aurora
2007-01-01
Packaging steel is more advantageously recovered and recycled than other packaging material due to its magnetic properties. The steel used for packaging is of high quality, and post-consumer waste therefore produces high-grade ferrous scrap. Recycling is thus an important issue for reducing raw material consumption, including iron ore, coal and energy. Household refuse management consists of collection/disposal, transport, and processing and treatment - incineration and composting being the most widely used methods in Spain. Total Spanish MSW production exceeds 21 million tons per year, of which 28.1% and 6.2% are treated in compost and incineration plants, respectively. This paper presents a comprehensive study of incineration and compost plants in Spain, including a review of the different processes and technologies employed and the characteristics and quality of the recovered ferrous scrap. Of the total amount of packaging steel scrap recovered from MSW, 38% comes from compost plants and 14% from incineration plants. Ferrous scrap from incineration plants presents a high degree of chemical alteration as a consequence of the thermal process to which the MSW is subjected, particularly the conditions in which the slag is cooled, and accordingly its quality diminishes. Fragmentation and magnetic separation processes produce an enhancement of the scrap quality. Ferrous scrap from compost plants has a high tin content, which negatively affects its recycling. Cleaning and detinning processes are required prior to recycling.
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Manu, M K; Kumar, Rakesh; Garg, Anurag
2017-06-01
Wet waste recycling at generation point will alleviate burden on the overflowing waste dumpsites in developing nations. Drum composting is a potential treatment option for such waste at individual or community level. The present study was aimed to produce compost from wet waste (primarily comprising food waste) in composting drums modified for improved natural air circulation. Effect of microbial inoculum and waste turning on composting process was also studied. The final results showed the production of matured and stable compost in the modified drums. Addition of the microbial inoculum resulted in thermophilic phase within a week time. The self-heating test and germination index (>80%) showed the production of non-phytotoxic and mature compost in the modified drums after 60days. The change in microbial population, humic substances and biological parameters (lignin, cellulose and hemicellulose) during the study is discussed. Moreover, the reduction in waste mass and volume is also reported. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Bioaerosols from composting facilities—a review
Wéry, Nathalie
2014-01-01
Bioaerosols generated at composting plants are released during processes that involve the vigorous movement of material such as shredding, compost pile turning, or compost screening. Such bioaerosols are a cause of concern because of their potential impact on both occupational health and the public living in close proximity to such facilities. The biological hazards potentially associated with bioaerosol emissions from composting activities include fungi, bacteria, endotoxin, and 1-3 β-glucans. There is a major lack of knowledge concerning the dispersal of airborne microorganisms emitted by composting plants as well as the potential exposure of nearby residents. This is due in part to the difficulty of tracing specifically these microorganisms in air. In recent years, molecular tools have been used to develop new tracers which should help in risk assessments. This review summarizes current knowledge of microbial diversity in composting aerosols and of the associated risks to health. It also considers methodologies introduced recently to enhance understanding of bioaerosol dispersal, including new molecular indicators and modeling. PMID:24772393
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Ren, Shengtao; Guo, Xiali; Lu, Aqian; Guo, Xiaoying; Wang, Yan; Sun, Guoping; Guo, Weiwei; Ren, Chaobin; Wang, Lianzhong
2018-05-26
This paper investigated the effect of co-composting of lincomycin mycelia dregs (LMDs) with furfural slag on the degradation of lincomycin, maturity and microbial communities. Results showed that after 66 days composting, the concentration of lincomycin was removed above 99%. The final pH, C/N and germination index (GI) all met the national standards in maturity. Enumeration of total cultivable microbes showed the composting process was not inhibited by the addition of LMDs. Microbial diversity suggested that co-composting was beneficial to increase the abundance and diversity of bacterial communities for LMDs' treatment. Canonical correlation analysis (CCA) indicated the bacteria communities were strongly affected by residual lincomycin, with lincomycin reduced greatly, microbial communities of T and CK became similar at the end of composting. The potential bacteria to degrade lincomycin were Anaerococcus, Peptostreptococcus, and Lactobacillus. Based on these results, this research indicated that the co-composting was a feasible treatment for LMDs. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Fungi diversity from different depths and times in chicken manure waste static aerobic composting.
Gu, Wenjie; Lu, Yusheng; Tan, Zhiyuan; Xu, Peizhi; Xie, Kaizhi; Li, Xia; Sun, Lili
2017-09-01
The Dirichlet multinomial mixtures mode was used to analyse illumina sequencing data to reveal both temporal and spatial variations of the fungi community present in the aerobic composting. Results showed that 670 operational taxonomic units (OTUs) were detected, and the dominant phylum was Ascomycota. There were four types of samples fungi communities during the composting process. Samples from the early composting stage were mainly grouped into type I and Saccharomycetales sp. was dominant. Fungi community in the medium composting stage were fallen into type II and III, Sordariales sp. and Acremonium alcalophilum, Saccharomycetales sp. and Scedosporium minutisporum were the dominant OTUs respectively. Samples from the late composting stage were mainly grouped into type IV and Scedosporium minutisporum was the dominant OTU; Scedosporium minutisporum was significantly affected by depth (P<0.05). Results indicate that time and depth both are factors that influence fungi distribution and variation in c waste during static aerobic composting. Copyright © 2017. Published by Elsevier Ltd.
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Onursal, Emrah; Ekinci, Kamil
2015-04-01
Rose oil is a specific essential oil that is produced mainly for the cosmetics industry in a few selected locations around the world. Rose oil production is a water distillation process from petals of Rosa damascena Mill. Since the oil content of the rose petals of this variety is between 0.3-0.4% (w/w), almost 4000 to 3000 kg of rose petals are needed to produce 1 kg of rose oil. Rose oil production is a seasonal activity and takes place during the relatively short period where the roses are blooming. As a result, large quantities of solid waste are produced over a limited time interval. This research aims: (i) to determine the possibilities of aerobic co-composting as a waste management option for rose oil processing waste with caged layer manure; (ii) to identify effects of different carbon sources - straw or sawdust on co-composting of rose oil processing waste and caged layer manure, which are both readily available in Isparta, where significant rose oil production also takes place; (iii) to determine the effects of different C/N ratios on co-composting by the means of organic matter decomposition and dry matter loss. Composting experiments were carried out by 12 identical laboratory-scale composting reactors (60 L) simultaneously. The results of the study showed that the best results were obtained with a mixture consisting of 50% rose oil processing waste, 64% caged layer manure and 15% straw wet weight in terms of organic matter loss (66%) and dry matter loss (38%). © The Author(s) 2015.
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ERIC Educational Resources Information Center
Swarthout, Flora L.
1993-01-01
Students are able to experience cellular respiration in action and become more informed about the environment by creating compost. This article describes an activity that brings a natural process into the classroom. (ZWH)
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A process-based model for cattle manure compost windrows: Model performance and application
USDA-ARS?s Scientific Manuscript database
A model was developed and incorporated in the Integrated Farm System Model (IFSM, v.4.3) that simulates important processes occurring during windrow composting of manure. The model, documented in an accompanying paper, predicts changes in windrow properties and conditions and the resulting emissions...
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Survival of pathogenic bacteria in compost with special reference to Escherichia coli.
Gong, Chun-ming; Koichi, Inoue; Shunji, Inanaga; Takashi, Someya
2005-01-01
Application of compost in agricultural practice could potentially cause contamination of foodstuffs with pathogenic bacteria such as Escherichia coli O157:H7 (E. Coli O157). We investigated pathogenic bacteria in compost collected from the compost facilities, and evaluated the survival of E. coli K12 and O157 in laboratory experiments. Out of 19 compost product samples, coliform bacteria and salmonella were detected in 7 and 3 samples respectively. The number of coliform bacteria was 1.8 x 10(2) to 2.5 x 10(6) CFU/g dw and that of salmonella was 4.2 x 10(1) to 6.0 x 10(3) CFU/g dw. Moreover, coliform bacteria, fecal coliform, E. coli and salmonella were detected during composting at 54 degrees C to 67 degrees C. The results indicated that moisture content was a very important factor to the heat sensitivity of pathogenic bacteria in compost, E. coil in compost of high moisture content was more sensitive than that in compost of low moisture content, cells harvested in logarithmic phase was more sensitive than these in stationary phase, and E. coli K12 was more sensitive than E. coli O157. Based on the D values, the lethal time of E. coli K12 and O157 from l0(8) to 10(0) CFU/g dw were 16.3 and 28.8 min, respectively, at 60 degrees C in compost with 40% moisture content. However, some E. coil cells survived in composting process at 54 degrees C to 67 degrees C. Water potential (low moisture content) and physiological aspects of bacteria (stationary phase) could explain only in part of the prolonged survival of E. coil in compost, and there should be some other factors that are conducive to bacterial survival in compost.
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Galvez-Sola, L; Moral, R; Perez-Murcia, M D; Perez-Espinosa, A; Bustamante, M A; Martinez-Sabater, E; Paredes, C
2010-02-15
Composting is an environmentally friendly alternative for the recycling of organic wastes and its use is increasing in recent years. An exhaustive monitoring of the composting process and of the final compost characteristics is necessary to certify that the values of compost characteristics are within the limits established by the legislation in order to obtain a safe and marketable product. The analysis of these parameters on each composting batch in the commercial composting plant is time-consuming and expensive. So, their estimation in the composting facilities based on the use of near infrared reflectance spectroscopy (NIRS) could be an interesting approach in order to monitor compost quality. In this study, more than 300 samples from 20 different composting procedures were used to calibrate and validate the NIRS estimation of compost properties (pH, electrical conductivity (EC), total organic matter (TOM), total organic carbon (TOC), total nitrogen (TN) and C/N ratio, macronutrient contents (N, P, K) and potentially pollutant element concentrations (Fe, Cu, Mn and Zn)). The composts used were elaborated using different organic wastes from agroindustrial activities (GS: grape stalk; EGM: exhausted grape marc; GM: grape marc; V: vinasse; CJW: citrus juice waste; Alpeorujo: olive-oil waste; AS: almond skin; EP: exhausted peat; TSW: tomato soup waste; SMS: spent mushroom substrate) co-composted with manures (CM: cattle manure; PM: poultry manure) or urban wastes (SS: sewage sludge) The estimation results showed that the NIRS technique needs to be fitted to each element and property, using specific spectrum transformations, in order to achieve an acceptable accuracy in the prediction. However, excellent prediction results were obtained for TOM and TOC, successful calibrations for pH, EC, Fe and Mn, and moderately successful estimations for TN, C/N ratio, P, K, Cu and Zn.
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Gutiérrez, M C; Martín, M A; Serrano, A; Chica, A F
2015-03-15
In this study, the evolution of odour concentration (ouE/m(3)STP) emitted during the pile composting of the organic fraction of municipal solid waste (OFMSW) was monitored by dynamic olfactometry. Physical-chemical variables as well as the respirometric variables were also analysed. The aim of this work was twofold. The first was to determine the relationship between odour and traditional variables to determine if dynamic olfactometry is a feasible and adequate technique for monitoring an aerobic stabilisation process (composting). Second, the composting process odour impact on surrounding areas was simulated by a dispersion model. The results showed that the decrease of odour concentration, total organic carbon and respirometric variables was similar (around 96, 96 y 98% respectively). The highest odour emission (5224 ouE/m(3)) was reached in parallel with the highest microbiological activity (SOUR and OD20 values of 25 mgO2/gVS · h and 70 mgO2/gVS, respectively). The validity of monitoring odour emissions during composting in combination with traditional and respirometric variables was demonstrated by the adequate correlation obtained between the variables. Moreover, the quantification of odour emissions by dynamic olfactometry and the subsequent application of the dispersion model permitted making an initial prediction of the impact of odorous emissions on the population. Finally, the determination of CO2 and CH4 emissions allowed the influence of composting process on carbon reservoirs and global warming to be evaluated. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Chen, Yukun; Jiang, Zhao; Zhang, Xiuyuan; Cao, Bo; Yang, Fan; Wang, Ziyi; Zhang, Ying
2017-11-01
This study investigated the degree of humification of dissolved organic matter (DOM) during different periods of cattle manure composting using ultraviolet-visible (UV-vis) and fluorescence spectroscopy (emission, synchronous scan, and excitation-emission matrix) and determined which method is more suitable for analysis of the humification degree of DOM. Two composting piles were prepared by mixing manure and corn straw. One pile (Pile A [PA]) contained inoculated exogenous composite agents at a ratio of 2% (v/v), and a pile without the addition of inoculants (PNA) served as the control treatment. The results showed that ultraviolet integrated absorption intensities in the range of 226 to 400 nm and 260 to 280 nm and specific ultraviolet absorbances at 254 and 280 nm of both PA and PNA gradually increased with composting time. Based on the fluorescence regional integration analysis and parallel factor analysis, the humic-like substances became the main components of the DOM after composting. Our study demonstrated that the humification degree of DOM was enhanced during composting and that the inoculation composite agent was beneficial for the humification of DOM at the mesophilic and thermophilic phases of the composting process. Moreover, the results of correlation analysis and principal component analysis demonstrated that the fluorescence spectral parameters evaluated the humification degree of DOM during the whole cattle manure composting process better than the UV-vis spectral parameters. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
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Bohacz, Justyna
2017-02-15
Environmentally friendly strategies of waste management are both part of legal solutions currently in place and a focus of interest worldwide. Large-scale composting plants are set up across various regions while home composting is becoming increasingly popular. A variety of microbial groups are successively at work during composting and enzymatic activities detected in the composting mass fluctuate accordingly. Changes in the activities of oxidoreductases and hydrolases, i.e. glucose oxidase, horseradish peroxidase, lignin peroxidase, laccase, xylanase, superoxide dismutase and keratinase, low-molecular weight compounds, i.e. methoxyphenolic and hydroxyphenolic compounds, and the relative level of superoxide radicals and glucose were determined periodically in water extracts of composts to investigate the process of biochemical transformations of ligninocellulose in relation to biothermal phases and to identify a potential priming effect in two composts containing different ratios of lignocellulosic waste and chicken feathers. Composting was conducted for 30weeks. An important aim of the study was to demonstrate that a positive priming effect was induced during composting of a variety of lignocellulosic waste types using native keratin (chicken feathers) as a source of N. The effect was more evident in compost containing grass, which was related to a more rapid depletion of easily available sources of C and energy (glucose) during composting. Ligninolytic enzymes known to biodegrade recalcitrant organic matter were induced in subsequent biothermal phases of composting. Compost I enriched with grass (pine bark, grass, sawdust and chicken feathers) exhibited a higher enzymatic activity than compost II which did not contain any grass but which had a greater number of hardly-degradable components (pine bark, wheat straw, sawdust, chicken feathers). Similar observations were made for the concentrations of low-molecular weight compounds. The enzymes activities and concentration of low-molecular weight compounds listed above can be used to estimate the biodegradation of lignocellulose during composting. Copyright © 2016 Elsevier B.V. All rights reserved.
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Soares, Micaela A R; Andrade, Sandra R; Martins, Rui C; Quina, Margarida J; Quinta-Ferreira, Rosa M
2012-01-01
Composting is one of the technologies recommended for pre-treating industrial eggshells (ES) before its application in soils, for calcium recycling. However, due to the high inorganic content of ES, a mixture of biodegradable materials is required to assure a successful procedure. In this study, an adequate organic blend composition containing potato peel (PP), grass clippings (GC) and wheat straw (WS) was determined by applying the simplex-centroid mixture design method to achieve a desired moisture content, carbon: nitrogen ratio and free air space for effective composting of ES. A blend of 56% PP, 37% GC and 7% WS was selected and tested in a self heating reactor, where 10% (w/w) of ES was incorporated. After 29 days of reactor operation, a dry matter reduction of 46% was achieved and thermophilic temperatures were maintained during 15 days, indicating that the blend selected by statistical approach was adequate for composting of ES.
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Effects of sulphur and Thiobacillus thioparus on cow manure aerobic composting.
Gu, Wenjie; Zhang, Fabao; Xu, Peizhi; Tang, Shuanhu; Xie, Kaizhi; Huang, Xu; Huang, Qiaoyi
2011-06-01
A simulated aerobic composting experiment was used to explore the effects of sulphur and Thiobacillus thioparus during six manure composting treatments. The addition of sulphur led to a decrease of the pH level within the range 6-6.3, which was lower than the control treatment (CK). The concentration of ammonium nitrogen in T1 (0.25% sulphur), T2 (0.5% sulphur), T3 (0.25% sulphur + T. thioparus) and T4 (0.5% sulphur + T. thioparus) were much higher than the ammonium N in CK. The results indicated that addition of sulphur could increase the concentration of ammonium N and reduce loss of nitrogen. However, excess sulphur had a negative effect on temperature and GI. Addition of T. thioparus could increase concentration of available S, alleviate these negative influences and reduce compost biological toxicity. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Zhang, Junya; Sui, Qianwen; Tong, Juan; Zhong, Hui; Wang, Yawei; Chen, Meixue; Wei, Yuansong
2018-05-21
Sewage sludge was generally considered a significant reservoir of antibiotic resistance genes (ARGs) and could enter agricultural systems as fertilizer after composting. Soil types and the discrepancy of sludge composts could have influenced the fate of antibiotic-resistant bacteria (ARB) following the land application of sludge composts, which deserved to be clarified. Thus, the fate of ARB and ARGs following the land application of three types of sludge composts (A, B, and C) to three different soils (red soil, loess, and black soil) was investigated. The results showed that tetX, which was enriched the most during composting, did not affect the soil resistome, whereas tetG did. Soil types influenced the dynamics of ARB and ARGs significantly, whereas no significant difference was observed among compost types. The advantage of reducing ARGs during the composting process in compost B did not extend to land application. Land application of composts influenced the microbial community significantly at the early stage, but the microbial community returned to the control pattern gradually. Changes in the microbial community contributed more to the dynamics of ARGs in red and black soil compared with other factors, including co-selection from heavy metals, horizontal gene transfer, biomass and environmental factors, whereas horizontal gene transfer, reflected by intI1 levels, contributed the most in loess. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Process Improvements: Aerobic Food Waste Composting at ISF Academy
NASA Astrophysics Data System (ADS)
Lau, Y. K.
2015-12-01
ISF Academy, a school with 1500 students in Hong Kong, installed an aerobic food waste composting system in November of 2013. The system has been operational for over seven months; we will be making improvements to the system to ensure the continued operational viability and quality of the compost. As a school we are committed to reducing our carbon footprint and the amount of waste we send to the local landfill. Over an academic year we produce approximately 27 metric tons of food waste. Our system processes the food waste to compost in 14 days and the compost is used by our primary school students in a organic farming project.There are two areas of improvement: a) if the composting system becomes anaerobic, there is an odor problem that is noticed by the school community; we will be testing the use of a bio-filter to eliminate the odor problem and, b) we will be working with an equipment vendor from Australia to install an improved grease trap system. The grease and oil that is collected will be sold to a local company here in Hong Kong that processes used cooking oil for making biofuels. This system will include a two stage filtration system and a heated vessel for separating the oil from the waste water.The third project will be to evaluate biodegradable cutlery for the compositing in the system. Currently, we use a significant quantity of non-biodegradable cutlery that is then thrown away after one use. Several local HK companies are selling biodegradable cutlery, but we need to evaluate the different products to determine which ones will work with our composting system. The food waste composting project at ISF Academy demonstrates the commitment of the school community to a greener environment for HK, the above listed projects will improve the operation of the system.
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Removal of dissolved textile dyes from wastewater by a compost sorbent
Tsui, L.S.; Roy, W.R.; Cole, M.A.
2003-01-01
The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb CI Acid Black 24, CI Acid Orange 74, CI Basic Blue 9, CI Basic Green 4, CI Direct Blue 71, CI Direct Orange 39, CI Reactive Orange 16 and CI Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.