Evaluation of a new pulping technology for pre-treating source-separated organic household waste prior to anaerobic digestion.

PubMed

Naroznova, Irina; Møller, Jacob; Larsen, Bjarne; Scheutz, Charlotte

2016-04-01

A new technology for pre-treating source-separated organic household waste prior to anaerobic digestion was assessed, and its performance was compared to existing alternative pre-treatment technologies. This pre-treatment technology is based on waste pulping with water, using a specially developed screw mechanism. The pre-treatment technology rejects more than 95% (wet weight) of non-biodegradable impurities in waste collected from households and generates biopulp ready for anaerobic digestion. Overall, 84-99% of biodegradable material (on a dry weight basis) in the waste was recovered in the biopulp. The biochemical methane potential for the biopulp was 469 ± 7 mL CH4/g ash-free mass. Moreover, all Danish and European Union requirements regarding the content of hazardous substances in biomass intended for land application were fulfilled. Compared to other pre-treatment alternatives, the screw-pulping technology showed higher biodegradable material recovery, lower electricity consumption and comparable water consumption. The higher material recovery achieved with the technology was associated with greater transfer of nutrients (N and P), carbon (total and biogenic) but also heavy metals (except Pb) to the produced biomass. The data generated in this study could be used for the environmental assessment of the technology and thus help in selecting the best pre-treatment technology for source separated organic household waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

Challenges and opportunities of biodegradable plastics: A mini review.

PubMed

Rujnić-Sokele, Maja; Pilipović, Ana

2017-02-01

The concept of materials coming from nature with environmental advantages of being biodegradable and/or biobased (often referred to as bioplastics) is very attractive to the industry and to the consumers. Bioplastics already play an important role in the fields of packaging, agriculture, gastronomy, consumer electronics and automotive, but still they have a very low share in the total production of plastics (currently about 1% of the about 300 million tonnes of plastic produced annually). Biodegradable plastics are often perceived as the possible solution for the waste problem, but biodegradability is just an additional feature of the material to be exploited at the end of its life in specific terms, in the specific disposal environment and in a specific time, which is often forgotten. They should be used as a favoured choice for the applications that demand a cheap way to dispose of the item after it has fulfilled its job (e.g. for food packaging, agriculture or medical products). The mini-review presents the opportunities and future challenges of biodegradable plastics, regarding processing, properties and waste management options.

A LABORATORY STUDY TO INVESTIGATE GASEOUS EMISSIONS AND SOLIDS DECOMPOSITION DURING COMPOSTING OF MUNICIPAL SOLID WASTE

EPA Science Inventory

The report gives results of a materials flow analysis performed for composting municipal solid waste (MSW) and specific biodegradable organic components of MSW. (NOTE: This work is part of an overall U.S. EPA project providing cost, energy, and materials flow information on diffe...

New perspectives in plastic biodegradation.

PubMed

Sivan, Alex

2011-06-01

During the past 50 years new plastic materials, in various applications, have gradually replaced the traditional metal, wood, leather materials. Ironically, the most preferred property of plastics--durability--exerts also the major environmental threat. Recycling has practically failed to provide a safe solution for disposal of plastic waste (only 5% out of 1 trillion plastic bags, annually produced in the US alone, are being recycled). Since the most utilized plastic is polyethylene (PE; ca. 140 million tons/year), any reduction in the accumulation of PE waste alone would have a major impact on the overall reduction of the plastic waste in the environment. Since PE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing synthetic polymers. Recent data showed that biodegradation of plastic waste with selected microbial strains became a viable solution. Copyright © 2011 Elsevier Ltd. All rights reserved.

DETERMINATION OF OPTIMAL TOXICANT LOADING FOR BIOLOGICAL CLOSURE OF A HAZARDOUS WASTE SITE

EPA Science Inventory

Information on Phase I and Phase Il of a multitask effort to achieve biological closure of an abandoned hazardous waste site. aste materials, in the form of buried sludges and lagoon wastes, were examined. ptimal loading levels were evaluated on the basis of biodegradative potent...

Organic wastes decomposition technology, perspective for long-term autonomous missions

NASA Astrophysics Data System (ADS)

Viacheslav, Ilyin; Korshunov, Denis; Mardanov, Robert; Starkova, Lyubov; Deshevaya, Elena; Smirnov, Igor

At present time there is no large problem in waste management in ISS space flight conditions, since spacecrafts "Progress" is used for it's removal from orbital station and the wastes burns in dense layers of Earth's atmosphere. However such method does not approach for far inter-planetary flights since interplanetary quarantine desires do not allow to deposit contaminated wastes outside the spacecraft. Essential part of wastes is formed by disposed means of personal hygiene and greenhouse wastes which are not safe from sanitary-epidemiological aspect. Above mentioned materials have one common feature: they can be subjected to biodegradation using different microbial compositions. Microbial decomposition of wastes as meets the main crite-ria of safety and power consumption. We investigated the effectiveness of method of disposed personal hygiene means biodegradation by anaerobic thermophiles with further purification of obtained decomposition products from chemical solvents with the help of mesophilic isolates in microaerophile conditions. Bacteria of Clostridium genera were selected for cellulolysis be-cause of their high specific endoglucanasic activity which less depends on substrate nature and relatively high growth rate on cellulose contaning substrates. As result some strains in case of optimal conditions (substrata pretreating, pH correction) decomposed means of personal hygiene with level of biodegradation up to 90With the purpose of purification, liqiud medi-ums originating from Closrtidium sp. exhibiting used like substrates for cellololitic fungi. It was shown that the cultures are able to change pH of media from slow-acid to neutral. Also the effectiveness of plant wastes biodegradation (vegetables homogenates) was studied using associations of mesophile aerobes trophically adapted to substrates. Rate of biodestruction of dry mass varied near 76To purify liquid products of biodegradation from chemicals cellulolytic fungal strains as well as bacterial mesophylic association was used. Prevalence of cultures for purification was depended on pH of culture liquors. Chemical content of gaseous phase of cul-ture liquors was also studied. As it comes from chromatomass spectrometry data there was tremendous decrease of organic admixtures in liquid products of biodegradation after purifi-cation by fungal and bacterial cultures. These cultures were capable to support sustainable growth, feeding by metabolites of bacteria, which perform primary biodegradation. Also there was evaluated prospective of application of biofuel cells in the process of biotransformation of different substrates. Application of electrogenic bacteria could be perspective approach in wastes biodegradation technology.

Biodegradation of paint stripper solvents in a modified gas lift loop bioreactor.

PubMed

Vanderberg-Twary, L; Steenhoudt, K; Travis, B J; Hanners, J L; Foreman, T M; Brainard, J R

1997-07-05

Paint stripping wastes generated during the decontamination and decommissioning of former nuclear facilities contain paint stripping organics (dichloromethane, 2-propanol, and methanol) and bulk materials containing paint pigments. It is desirable to degrade the organic residues as part of an integrated chemical-biological treatment system. We have developed a modified gas lift loop bioreactor employing a defined consortium of Rhodococcus rhodochrous strain OFS and Hyphomicrobium sp. DM-2 that degrades paint stripper organics. Mass transfer coefficients and kinetic constants for biodegradation in the system were determined. It was found that transfer of organic substrates from surrogate waste into the air and further into the liquid medium in the bioreactor were rapid processes, occurring within minutes. Monod kinetics was employed to model the biodegradation of paint stripping organics. Analysis of the bioreactor process was accomplished with BIOLAB, a mathematical code that simulates coupled mass transfer and biodegradation processes. This code was used to fit experimental data to Monod kinetics and to determine kinetic parameters. The BIOLAB code was also employed to compare activities in the bioreactor of individual microbial cultures to the activities of combined cultures in the bioreactor. This code is of benefit for further optimization and scale-up of the bioreactor for treatment of paint stripping and other volatile organic wastes in bulk materials.

Biological Production of Methane from Lunar Mission Solid Waste: An Initial Feasibility Assessment

NASA Astrophysics Data System (ADS)

Strayer, Richard; Garland, Jay; Janine, Captain

A preliminary assessment was made of the potential for biological production of methane from solid waste generated during an early planetary base mission to the moon. This analysis includes: 1) estimation of the amount of biodegradable solid waste generated, 2) background on the potential biodegradability of plastics given their significance in solid wastes, and 3) calculation of potential methane production from the estimate of biodegradable waste. The completed analysis will also include the feasibility of biological methane production costs associated with the biological processing of the solid waste. NASA workshops and Advanced Life Support documentation have estimated the projected amount of solid wastes generated for specific space missions. From one workshop, waste estimates were made for a 180 day transit mission to Mars. The amount of plastic packaging material was not specified, but our visual examination of trash returned from stocktickerSTS missions indicated a large percentage would be plastic film. This plastic, which is not biodegradable, would amount to 1.526 kgdw crew-1 d-1 or 6.10 kgdw d-1 for a crew of 4. Over a mission of 10 days this would amount to 61 kgdw of plastics and for an 180 day lunar surface habitation it would be nearly 1100 kgdw . Approx. 24 % of this waste estimate would be biodegradable (human fecal waste, food waste, and paper), but if plastic packaging was replaced with biodegradable plastic, then 91% would be biodegradable. Plastics are man-made long chain polymeric molecules, and can be divided into two main groups; thermoplastics and thermoset plastics. Thermoplastics comprise over 90% of total plastic use in the placecountry-regionUnited States and are derived from polymerization of olefins via breakage of the double bond and subsequent formation of additional carbon to carbon bonds. The resulting sole-carbon chain polymers are highly resistant to biodegradation and hydrolytic cleavage. Common thermoplastics include low density polyethylene (packaging, bags), high density polyethylene (bottles, containers, pipes), polystyrene (tanks, containers), polypropylene (tanks, containers), and polyvinylchloride (pipes, containers). Thermoset plastics are formed by the condensation of alcohols or amines to form polyesters or polyamides, and are typically solidified after heating. As opposed to the linear structure of thermoplastic, thermoset plastics have a cross-linked structure which results in higher strength. The most common thermoset plastic is polyurethane which is used for coatings, insulation, paints, and packing. Given both the concerns over pollution reduction and energy conservation, significant efforts are underway on Earth to evaluate biodegradable plastics made from renewable feedstocks; the following summarizes the current state of these efforts. Production of biodegradable plastics involves either the introduction of biodegradable or photo-oxidizable components into the polymer chain or the use of biodegradable polymers themselves. The first approach is based on the observation that polyolefins of low molecular weight (<500 Da) are biodegradable. Insertion of structures susceptible to either photoor chemical degradation within the overall polyolefins chain (which are of 4 - 28 kDa molecular weight), can produce segments sufficiently small to be assimilated and degraded by microorganisms. Biodegradable polymers based strictly on nonpetroleum, biologically-based material have been developed, including some which are used to make currently marketed products. Polyhydroxyalkanoates (PHAs) are polyesters which are accumulated as carbon storage materials by microorganisms under nutrient limiting conditions. MirelTM , a "bioplastic" based on stocktickerPHA produced from microbial fermentation of sugars or oils from vegetables crops, is being produced by TellesTM . The company markets MirelTM bioplastics for use in molding, coatings, films, adhesives, and fibers. Another type of bioplastic is based on polylactic acid, or stocktickerPLA. Starch, typically from corn, is fermented by bacteria to yield lactic acid which is then used to synthesize the stocktickerPLA polymer. stocktickerPLA can be degraded via a combination of abiotic hydrolysis and microbial degradation. NatureWorks LLC markets stocktickerPLA-based plastics (NatureWorks R , IngeoTM ) for a variety of applications, including high-value films, rigid thermoformed food and beverage containers, coated papers and boards and other packaging applications. This review suggests that biodegradable plastics may be feasible for use on near-term lunar missions. Biodegradable plastics products are commercially available, and cost, the main limitation to terrestrial use, is not an issue for the small-scale, specialty use by NASA. If the plastic content of the lunar mission solid waste stream is biodegradable, then a potential yield of methane from the waste can be estimated. Investigators at the placePlaceTypeUniversity of PlaceNameFlorida have reported on a three-stage anaerobic composting system for treatment of solid wastes expected in an Advanced Life Support System for space surface habitation. Their system, a sequential batch anaerobic composter (SEBAC) has been demonstrated for a variety of terrestrial solid wastes. Results for methane production rate from a simulated stocktickerALS solid waste of inedible rice crop debris, paper, and simulated feces averaged 0.30 L CH4 per gdw volatile solids (VS, i.e., organic matter) added. If we extrapolate from their results and assume that the VS in space mission solid waste is 100% biodegradable, then a potential for 620 LCH4 crew-1 d-1 might be obtained with a comparable SEBAC. For a crew of four, 2480 LCH4 d-1 (or 110.7 molesCH4 d-1 , 1772 gCH4 d-1 , or 3.90 lbCH4 d-1 )., would be produced. Over a 180 day surface habitation, this generation rate would yield a total of 446,000 LCH4 (319 kgCH4 , 702 lbCH4 ). The next step in this effort is to estimate the costs of biological processing system required to convert the solid waste steam to methane. We will employ equivalent system mass (ESM) analysis to define the costs of the system in terms of energy, mass, and manpower required for processing, allowing for a better estimation of the net benefit of this in situ resource utilization approach.

Researches on the development of new composite materials complete / partially biodegradable using natural textile fibers of new vegetable origin and those recovered from textile waste

NASA Astrophysics Data System (ADS)

Todor, M. P.; Bulei, C.; Heput, T.; Kiss, I.

2018-01-01

The objective of the research is to develop new fully / partially biodegradable composite materials by using new natural fibers and those recovered from various wastes. Thus, the research aims to obtain some composites with matrix of various types of polymeric materials and the reinforcement phase of textile materials (of different natures, morphologies and composites) so that the resulting products to be (bio)degradable. The textile inserts used as raffle are ecological, non-toxic and biodegradable and they contain (divided or in combination) bast fibers (flax, hemp, jute) and other vegetable fibers (cotton, wool) as plain yarn or fabric, which can replace fibers of glass commonly used in polymeric composites. The main activities described in this article are carried out during the first phase of the research (phase I - initiation of research) and they are oriented towards the choice of types of textile inserts from which the composites will be obtained (the materials needed for the raffle), the choice of the types of polymers (the necessary materials for matrices) and choosing the variants of composites with different types and proportions of the constituent content (proposals and working variants) and choosing the right method for obtaining samples of composite materials (realization technology). The purpose of the research is to obtain composite materials with high structural, thermo-mechanical and / or tribological performances, according to ecological norms and international requirements in order to replace the existing classical materials, setting up current, innovative and high performance solutions, for applications in top areas such as automotive industry and not only.

40 CFR 265.1084 - Waste determination procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... biodegradation efficiency (Rbio) for a treated hazardous waste. (i) The fraction of organics biodegraded (Fbio... biodegradation efficiency, percent. Fbio = Fraction of organic biodegraded as determined in accordance with the... biodegradation rate (MRbio) for a treated hazardous waste. (i) The MRbio shall be determined based on results for...

40 CFR 265.1084 - Waste determination procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... biodegradation efficiency (Rbio) for a treated hazardous waste. (i) The fraction of organics biodegraded (Fbio... biodegradation efficiency, percent. Fbio = Fraction of organic biodegraded as determined in accordance with the... biodegradation rate (MRbio) for a treated hazardous waste. (i) The MRbio shall be determined based on results for...

40 CFR 265.1084 - Waste determination procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... biodegradation efficiency (Rbio) for a treated hazardous waste. (i) The fraction of organics biodegraded (Fbio... biodegradation efficiency, percent. Fbio = Fraction of organic biodegraded as determined in accordance with the... biodegradation rate (MRbio) for a treated hazardous waste. (i) The MRbio shall be determined based on results for...

40 CFR 265.1084 - Waste determination procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... biodegradation efficiency (Rbio) for a treated hazardous waste. (i) The fraction of organics biodegraded (Fbio... biodegradation efficiency, percent. Fbio = Fraction of organic biodegraded as determined in accordance with the... biodegradation rate (MRbio) for a treated hazardous waste. (i) The MRbio shall be determined based on results for...

New insights into polyurethane biodegradation and realistic prospects for the development of a sustainable waste recycling process.

PubMed

Cregut, Mickael; Bedas, M; Durand, M-J; Thouand, G

2013-12-01

Polyurethanes are polymeric plastics that were first used as substitutes for traditional polymers suspected to release volatile organic hazardous substances. The limitless conformations and formulations of polyurethanes enabled their use in a wide variety of applications. Because approximately 10 Mt of polyurethanes is produced each year, environmental concern over their considerable contribution to landfill waste accumulation appeared in the 1990s. To date, no recycling processes allow for the efficient reuse of polyurethane waste due to their high resistance to (a)biotic disturbances. To find alternatives to systematic accumulation or incineration of polyurethanes, a bibliographic analysis was performed on major scientific advances in the polyurethane (bio)degradation field to identify opportunities for the development of new technologies to recondition this material. Until polymers exhibiting oxo- or hydro-biodegradative traits are generated, conventional polyurethanes that are known to be only slightly biodegradable are of great concern. The research focused on polyurethane biodegradation highlights recent attempts to reprocess conventional industrial polyurethanes via microbial or enzymatic degradation. This review describes several wonderful opportunities for the establishment of new processes for polyurethane recycling. Meeting these new challenges could lead to the development of sustainable management processes involving polymer recycling or reuse as environmentally safe options for industries. The ability to upgrade polyurethane wastes to chemical compounds with a higher added value would be especially attractive. © 2013.

USE OF ALTERED MICROORGANISMS FOR FIELD BIODEGRADATION OF HAZARDOUS MATERIALS

EPA Science Inventory

The large amount of hazardous waste generated and disposed of has given rise to environmental conditions requiring remedial treatment. he use of landfills has traditionally been a cost-effective means to dispose of waste. owever, increased costs of transportation and decreasing n...

Improving material and energy recovery from the sewage sludge and biomass residues.

PubMed

Kliopova, Irina; Makarskienė, Kristina

2015-02-01

Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10-40 mm) of pre-composted materials--sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg(-1) of the net calorific value, about 23% were composted, the rest--evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning, comparison analysis with widely used bio-fuel-sawdust and conclusions made are presented. Copyright © 2014 Elsevier Ltd. All rights reserved.

Saponification of fatty slaughterhouse wastes for enhancing anaerobic biodegradability.

PubMed

Battimelli, Audrey; Carrère, Hélène; Delgenès, Jean-Philippe

2009-08-01

The thermochemical pretreatment by saponification of two kinds of fatty slaughterhouse waste--aeroflotation fats and flesh fats from animal carcasses--was studied in order to improve the waste's anaerobic degradation. The effect of an easily biodegradable compound, ethanol, on raw waste biodegradation was also examined. The aims of the study were to enhance the methanisation of fatty waste and also to show a link between biodegradability and bio-availability. The anaerobic digestion of raw waste, saponified waste and waste with a co-substrate was carried out in batch mode under mesophilic and thermophilic conditions. The results showed little increase in the total volume of biogas, indicating a good biodegradability of the raw wastes. Mean biogas volume reached 1200 mL/g VS which represented more than 90% of the maximal theoretical biogas potential. Raw fatty wastes were slowly biodegraded whereas pretreated wastes showed improved initial reaction kinetics, indicating a better initial bio-availability, particularly for mesophilic runs. The effects observed for raw wastes with ethanol as co-substrate depended on the process temperature: in mesophilic conditions, an initial improvement was observed whereas in thermophilic conditions a significant decrease in biodegradability was observed.

[Agroindustrial wastes methanization and bacterial composition in anaerobic digestion].

PubMed

González-Sánchez, María E; Pérez-Fabiel, Sergio; Wong-Villarreal, Arnoldo; Bello-Mendoza, Ricardo; Yañez-Ocampo, Gustavo

2015-01-01

The tons of organic waste that are annually generated by agro-industry, can be used as raw material for methane production. For this reason, it is important to previously perform biodegradability tests to organic wastes for their full scale methanization. This paper addresses biodegradability, methane production and the behavior of populations of eubacteria and archaeabacteria during anaerobic digestion of banana, mango and papaya agroindustrial wastes. Mango and banana wastes had higher organic matter content than papaya in terms of their volatile solids and total solid rate (94 and 75% respectively). After 63 days of treatment, the highest methane production was observed in banana waste anaerobic digestion: 63.89ml CH4/per gram of chemical oxygen demand of the waste. In the PCR-DGGE molecular analysis, different genomic footprints with oligonucleotides for eubacteria and archeobacteria were found. Biochemical methane potential results proved that banana wastes have the best potential to be used as raw material for methane production. The result of a PCR- DGGE analysis using specific oligonucleotides enabled to identify the behavior of populations of eubacteria and archaeabacteria present during the anaerobic digestion of agroindustrial wastes throughout the process. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Biodegradation and flushing of MBT wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siddiqui, A.A., E-mail: aasiddiqui.cv@amu.ac.in; Richards, D.J.; Powrie, W.

Highlights: • Stabilization was achieved for MBT wastes of different degrees of pretreatment. • About 92% reduction in the gas generation compared with raw MSW. • Pretreatment resulted in reduced TOC, nitrogen and heavy metals in leachate. • A large proportion of carbon and nitrogen remained in the waste material. - Abstract: Mechanical–biological treatment (MBT) processes are increasingly being adopted as a means of diverting biodegradable municipal waste (BMW) from landfill, for example to comply with the EU Landfill Directive. However, there is considerable uncertainty concerning the residual pollution potential of such wastes. This paper presents the results of laboratorymore » experiments on two different MBT waste residues, carried out to investigate the remaining potential for the generation of greenhouse gases and the flushing of contaminants from these materials when landfilled. The potential for gas generation was found to be between 8% and 20% of that for raw MSW. Pretreatment of the waste reduced the potential for the release of organic carbon, ammoniacal nitrogen, and heavy metal contents into the leachate; and reduced the residual carbon remaining in the waste after final degradation from ∼320 g/kg dry matter for raw MSW to between 183 and 195 g/kg dry matter for the MBT wastes.« less

[Biodegradation of polyethylene].

PubMed

Yang, Jun; Song, Yi-ling; Qin, Xiao-yan

2007-05-01

Plastic material is one of the most serious solid wastes pollution. More than 40 million tons of plastics produced each year are discarded into environment. Plastics accumulated in the environment is highly resistant to biodegradation and not be able to take part in substance recycle. To increase the biodegradation efficiency of plastics by different means is the main research direction. This article reviewed the recent research works of polyethylene biodegradation that included the modification and pretreatment of polyethylene, biodegradation pathway, the relevant microbes and enzymes and the changes of physical, chemical and biological properties after biodegradation. The study directions of exploiting the kinds of life-forms of biodegradation polyethylene except the microorganisms, isolating and cloning the key enzymes and gene that could produce active groups, and enhancing the study on polyethylene biodegradation without additive were proposed.

40 CFR 265.1084 - Waste determination procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... to determine the organic biodegradation efficiency (Rbio) for a treated hazardous waste. (i) The... Where: Rbio = Organic biodegradation efficiency, percent. Fbio = Fraction of organic biodegraded as... to determine the actual organic mass biodegradation rate (MRbio) for a treated hazardous waste. (i...

Enhancement of anaerobic biodegradability of flower stem wastes with vegetable wastes by co-hydrolysis.

PubMed

Zhang, Bo; He, Pinjing; Lü, Fan; Shao, Liming

2008-01-01

The vegetable wastes and flower stems were co-digested to evaluate the anaerobic hydrolysis performance of difficultly biodegradable organic wastes by introducing readily biodegradable organic wastes. The experiments were carried out in batches. When the vegetable wastes were mixed with the flower stems at the dry weight ratio of 1 to 13, the overall hydrolysis rate increased by 8%, 12%, and 2% according to the carbon, nitrogen, and total solid (TS) conversion rate, respectively. While the dry weight ratio was designed as 1 to 3, there was a respective rise of 5%, 15%, and 4% in the conversion rate of carbon, nitrogen, and TS. The enhancement of anaerobic hydrolysis from the mixed vegetable wastes and flower stems can be attributed to the formation of volatile fatty acids (VFA) and nutrient supplement like nitrogen content. The maximum VFA concentration can achieve 1.7 g/L owing to the rapid acidification of vegetable wastes, loosing the structure of lignocellulose materials. The statistic bivariate analysis revealed that the hydrolysis performance was significantly related to the physical and biochemical compositions of the feeding substrate. Especially, the soluble carbon concentration in the liquid was significantly positively correlated to the concentration of nitrogen and hemicellulose, and negatively correlated to the concentration of carbon and lignocellulose in the feeding substrate, suggesting that the regulation and control of feedstock can have an important influence on the anaerobic hydrolysis of organic wastes.

Characterization of selected municipal solid waste components to estimate their biodegradability.

PubMed

Bayard, R; Benbelkacem, H; Gourdon, R; Buffière, P

2018-06-15

Biological treatments of Residual Municipal Solid Waste (RMSW) allow to divert biodegradable materials from landfilling and recover valuable alternative resources. The biodegradability of the waste components needs however to be assessed in order to design the bioprocesses properly. The present study investigated complementary approaches to aerobic and anaerobic biotests for a more rapid evaluation. A representative sample of residual MSW was collected from a Mechanical Biological Treatment (MBT) plant and sorted out into 13 fractions according to the French standard procedure MODECOM™. The different fractions were analyzed for organic matter content, leaching behavior, contents in biochemical constituents (determined by Van Soest's acid detergent fiber method), Biochemical Oxygen Demand (BOD) and Bio-Methane Potential (BMP). Experimental data were statistically treated by Principal Components Analysis (PCA). Cumulative oxygen consumption from BOD tests and cumulative methane production from BMP tests were found to be positively correlated in all waste fractions. No correlation was observed between the results from BOD or BMP bioassays and the contents in cellulose-like, hemicelluloses-like or labile organic compounds. No correlation was observed either with the results from leaching tests (Soluble COD). The contents in lignin-like compounds, evaluated as the non-extracted RES fraction in Van Soest's method, was found however to impact negatively the biodegradability assessed by BOD or BMP tests. Since cellulose, hemicelluloses and lignin are the polymers responsible for the structuration of lignocellulosic complexes, it was concluded that the structural organization of the organic matter in the different waste fractions was more determinant on biodegradability than the respective contents in individual biopolymers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biodegradability study of high-erucic-acid-rapeseed-oil-based lubricant additives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, E.; Crawford, R.L.; Shanahan, A.

1995-12-31

A variety of high-erucic-acid-rapeseed (HEAR)-oil-based lubricants, lubricant additives, and greases were examined for biodegradability at the University of Idaho Center for Hazardous Waste Remediation Research. Two standard biodegradability tests were employed, a currently accepted US Environmental Protection Agency (EPA) protocol and the Sturm Test. As is normal for tests that employ variable inocula such as sewage as a source of microorganisms, these procedures yielded variable results from one repetition to another. However, a general trend of rapid and complete biodegradability of the HEAR-oil-based materials was observed.

Review of Concrete Biodeterioration in Relation to Buried Nuclear Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turick, C; Berry, C.

Long-term storage of low level radioactive material in below ground concrete disposal units (DUs) (Saltstone Disposal Facility) is a means of depositing wastes generated from nuclear operations of the U.S. Department of Energy. Based on the currently modeled degradation mechanisms, possible microbial induced effects on the structural integrity of buried low level wastes must be addressed. Previous international efforts related to microbial impacts on concrete structures that house low level radioactive waste showed that microbial activity can play a significant role in the process of concrete degradation and ultimately structural deterioration. This literature review examines the recent research in thismore » field and is focused on specific parameters that are applicable to modeling and prediction of the fate of concrete vaults housing stored wastes and the wastes themselves. Rates of concrete biodegradation vary with the environmental conditions, illustrating a need to understand the bioavailability of key compounds involved in microbial activity. Specific parameters require pH and osmotic pressure to be within a certain range to allow for microbial growth as well as the availability and abundance of energy sources like components involved in sulfur, iron and nitrogen oxidation. Carbon flow and availability are also factors to consider in predicting concrete biodegradation. The results of this review suggest that microbial activity in Saltstone, (grouted low level radioactive waste) is unlikely due to very high pH and osmotic pressure. Biodegradation of the concrete vaults housing the radioactive waste however, is a possibility. The rate and degree of concrete biodegradation is dependent on numerous physical, chemical and biological parameters. Results from this review point to parameters to focus on for modeling activities and also, possible options for mitigation that would minimize concrete biodegradation. In addition, key chemical components that drive microbial activity on concrete surfaces are discussed.« less

Assessing the effect of biodegradable and degradable plastics on the composting of green wastes and compost quality.

PubMed

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.

Improving material and energy recovery from the sewage sludge and biomass residues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kliopova, Irina, E-mail: irina.kliopova@ktu.lt; Makarskienė, Kristina

2015-02-15

Highlights: • SRF production from 10–40 mm fraction of pre-composted sludge and biomass residues. • The material and energy balance of compost and SRF production. • Characteristics of raw materials and classification of produced SRF. • Results of the efficiency of energy recovery, comparison analysis with – sawdust. - Abstract: Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives ofmore » sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10–40 mm) of pre-composted materials – sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg{sup −1} of the net calorific value, about 23% were composted, the rest – evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning, comparison analysis with widely used bio-fuel–sawdust and conclusions made are presented.« less

Biodegradation of low-density polyethylene (LDPE) by isolated fungi in solid waste medium.

PubMed

Zahra, Sahebnazar; Abbas, Shojaosadati Seyed; Mahsa, Mohammad-Taheri; Mohsen, Nosrati

2010-03-01

In this study, biodegradation of low-density polyethylene (LDPE) by isolated landfill-source fungi was evaluated in a controlled solid waste medium. The fungi, including Aspergillus fumigatus, Aspergillus terreus and Fusarium solani, were isolated from samples taken from an aerobic aged municipal landfill in Tehran. These fungi could degrade LDPE via the formation of a biofilm in a submerged medium. In the sterilized solid waste medium, LPDE films were buried for 100 days in a 1-L flask containing 400 g sterile solid waste raw materials at 28 degrees C. Each fungus was added to a separate flask. The moisture content and pH of the media were maintained at the optimal levels for each fungus. Photo-oxidation (25 days under UV-irradiation) was used as a pretreatment of the LDPE samples. The progress of the process was monitored by measurement of total organic carbon (TOC), pH, temperature and moisture. The results obtained from monitoring the process using isolated fungi under sterile conditions indicate that these fungi are able to grow in solid waste medium. The results of FT-IR and SEM analyses show that A. terreus and A. fumigatus, despite the availability of other organic carbon of materials, could utilize LDPE as carbon source. While there has been much research in the field of LDPE biodegradation under solid conditions, this is the first report of degradation of LDPE by A. fumigatus. Copyright 2009 Elsevier Ltd. All rights reserved.

Biodegradation of low-density polyethylene (LDPE) by isolated fungi in solid waste medium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zahra, Sahebnazar; Abbas, Shojaosadati Seyed, E-mail: sa_shoja@modares.ac.i; Mahsa, Mohammad-Taheri

In this study, biodegradation of low-density polyethylene (LDPE) by isolated landfill-source fungi was evaluated in a controlled solid waste medium. The fungi, including Aspergillus fumigatus, Aspergillus terreus and Fusarium solani, were isolated from samples taken from an aerobic aged municipal landfill in Tehran. These fungi could degrade LDPE via the formation of a biofilm in a submerged medium. In the sterilized solid waste medium, LPDE films were buried for 100 days in a 1-L flask containing 400 g sterile solid waste raw materials at 28 deg. C. Each fungus was added to a separate flask. The moisture content and pHmore » of the media were maintained at the optimal levels for each fungus. Photo-oxidation (25 days under UV-irradiation) was used as a pretreatment of the LDPE samples. The progress of the process was monitored by measurement of total organic carbon (TOC), pH, temperature and moisture. The results obtained from monitoring the process using isolated fungi under sterile conditions indicate that these fungi are able to grow in solid waste medium. The results of FT-IR and SEM analyses show that A. terreus and A. fumigatus, despite the availability of other organic carbon of materials, could utilize LDPE as carbon source. While there has been much research in the field of LDPE biodegradation under solid conditions, this is the first report of degradation of LDPE by A. fumigatus.« less

Assessment and quantification of plastics waste generation in major 60 cities of India.

PubMed

Nalini, R; Srinivasulu, B; Shit, Subhas C; Nigam, Suneel Kumar; Akolkar, A B; Dwivedfi, R K

2013-04-01

Polymers or plastics materials registered rapid growth in 1970s, 1980s and 1990s at the rate of 2-2.5 times the GDP growth in India. The demand for plastic raw material got more than doubled from 3.3 Million Metric Ton to 6.8 Million Metric Tons in 2010 attributed mainly to rapid urbanization, spread of retail chains, plastics based packaging from grocery to food and vegetable products to cosmetics and consumer items. Plastics packages have its merits over many of conventional materials in the related sector but unless they are collected back effectively after their use to go into recycling process, they become an eyesore in the stream of Municipal Solid Waste (MSW) due to high visibility. As the synthetic and conventional plastics are non-biodegradable in nature, these remain in the dump yards/ landfills for several years, if not collected properly. Due to non- biodegradability, plastics waste remains in the environment for several years, if not collected and disposing plastics wastes at landfills are unsafe since toxic chemicals leach out into the soil and as they contaminate soil and underground water quality. The municipal solid waste also increasing day-by-day due to the inefficient source collection, segregation and transmission of plastics waste for recycling and reusing. In order to find out the realistic plastics waste generation, a study on assessment and quantification of plastics waste has been carried out by CPCB in collaboration with CIPET on selected 60 major cities of India.

From "farm to fork" strawberry system: current realities and potential innovative scenarios from life cycle assessment of non-renewable energy use and green house gas emissions.

PubMed

Girgenti, Vincenzo; Peano, Cristiana; Baudino, Claudio; Tecco, Nadia

2014-03-01

In this study, we analysed the environmental profile of the strawberry industry in Northern Italy. The analysis was conducted using two scenarios as reference systems: strawberry crops grown in unheated plastic tunnels using currently existing cultivation techniques, post-harvest management practices and consumption patterns (scenario 1) and the same strawberry cultivation chain in which some of the materials used were replaced with bio-based materials (scenario 2). In numerous studies, biodegradable polymers have been shown to be environmentally friendly, thus potentially reducing environmental impacts. These materials can be recycled into carbon dioxide and water through composting. Many materials, such as Mater-BI® and PLA®, are also derived from renewable resources. The methodology chosen for the environmental analysis was a life cycle assessment (LCA) based on a consequential approach developed to assess a product's overall environmental impact from the production system to its usage and disposal. In the field stage, a traditional mulching film (non-biodegradable) could be replaced with a biodegradable product. This change would result in waste production of 0 kg/ha for the bio-based product compared to 260 kg/ha of waste for polyethylene (PE). In the post-harvest stage, the issue addressed was the use and disposal of packaging materials. The innovative scenario evaluated herein pertains to the use of new packaging materials that increase the shelf life of strawberries, thereby decreasing product losses while increasing waste management efficiency at the level of a distribution platform and/or sales outlet. In the event of product deterioration or non-sale of the product, the packaging and its contents could be collected together as organic waste without any additional processes because the packaging is compostable according to EN13432. Scenario 2 would achieve reductions of 20% in the global warming potential and non-renewable energy impact categories. Copyright © 2013 Elsevier B.V. All rights reserved.

Slaughterhouse fatty waste saponification to increase biogas yield.

PubMed

Battimelli, A; Torrijos, M; Moletta, R; Delgenès, J P

2010-05-01

A thermochemical pretreatment, i.e. saponification, was optimised in order to improve anaerobic biodegradation of slaughterhouse wastes such as aeroflotation grease and flesh fats from cattle carcass. Anaerobic digestion of raw wastes, as well as of wastes saponified at different temperatures (60 degrees C, 120 degrees C and 150 degrees C) was conducted in fed-batch reactors under mesophilic condition and the effect of different saponification temperatures on anaerobic biodegradation and on the long-chain fatty acids (LCFAs) relative composition was assessed. Even after increasing loads over a long period of time, raw fatty wastes were biodegraded slowly and the biogas potentials were lower than those of theoretical estimations. In contrast, pretreated wastes exhibited improved batch biodegradation, indicating a better initial bio-availability, particularly obvious for carcass wastes. However, LCFA relative composition was not significantly altered by the pretreatment. Consequently, the enhanced biodegradation should be attributed to an increased initial bio-availability of fatty wastes without any modification of their long chain structure which remained slowly biodegradable. Finally, saponification at 120 degrees C achieved best performances during anaerobic digestion of slaughterhouse wastes. Copyright 2009 Elsevier Ltd. All rights reserved.

Trash--Our Only Growing Resource. Environmental Ecological Education Project.

ERIC Educational Resources Information Center

Giebelhausen, Maribeth R.; And Others

With the increases in population and technology, non-biodegradable materials like plastic, glass, and aluminum and waste disposal have become very real problems in out society. This unit, designed for seventh-grade students, focuses on the problems of waste disposal and examines the function of recycling, the role of the consumer in determining…

Evaluation of the rotary drum reactor process as pretreatment technology of municipal solid waste for thermophilic anaerobic digestion and biogas production.

PubMed

Gikas, Petros; Zhu, Baoning; Batistatos, Nicolas Ion; Zhang, Ruihong

2018-06-15

Municipal solid waste (MSW) contains a large fraction of biodegradable organic materials. When disposed in landfills, these materials can cause adverse environmental impact due to gaseous emissions and leachate generation. This study was performed with an aim of effectively separating the biodegradable materials from a Mechanical Biological Treatment (MBT) facility and treating them in well-controlled anaerobic digesters for biogas production. The rotary drum reactor (RDR) process (a sub-process of the MBT facilities studied in the present work) was evaluated as an MSW pretreatment technology for separating and preparing the biodegradable materials in MSW to be used as feedstock for anaerobic digestion. The RDR processes used in six commercial MSW treatment plants located in the USA were surveyed and sampled. The samples of the biodegradable materials produced by the RDR process were analyzed for chemical and physical characteristics as well as anaerobically digested in the laboratory using batch reactors under thermophilic conditions. The moisture content, TS, VS and C/N of the samples varied between 64.7 and 44.4%, 55.6 to 35.3%, 27.0 to 41.3% and 24.5 to 42.7, respectively. The biogas yield was measured to be between 533.0 and 675.6 mL g -1 VS after 20 days of digestion. Approximately 90% of the biogas was produced during the first 13 days. The average methane content of the biogas was between 58.0 and 59.9%. The results indicated that the biodegradable materials separated from MSW using the RDR processes could be used as an excellent feedstock for anaerobic digestion. The digester residues may be further processed for compost production or further energy recovery by using thermal conversion processes such as combustion or gasification. Copyright © 2017. Published by Elsevier Ltd.

Environmental impact of rejected materials generated in organic fraction of municipal solid waste anaerobic digestion plants: Comparison of wet and dry process layout.

PubMed

Colazo, Ana-Belén; Sánchez, Antoni; Font, Xavier; Colón, Joan

2015-09-01

Anaerobic digestion of source separated organic fraction of municipal solid waste is an increasing waste valorization alternative instead of incineration or landfilling of untreated biodegradable wastes. Nevertheless, a significant portion of biodegradable wastes entering the plant is lost in pre-treatments and post-treatments of anaerobic digestion facilities together with other improper materials such as plastics, paper, textile materials and metals. The rejected materials lost in these stages have two main implications: (i) less organic material enters to digesters and, as a consequence, there is a loss of biogas production and (ii) the rejected materials end up in landfills or incinerators contributing to environmental impacts such as global warming or eutrophication. The main goals of this study are (i) to estimate potential losses of biogas in the rejected solid materials generated during the pre- and post-treatments of two full-scale anaerobic digestion facilities and (ii) to evaluate the environmental burdens associated to the final disposal (landfill or incineration) of these rejected materials by means of Life Cycle Assessment. This study shows that there is a lost of potential biogas production, ranging from 8% to 15%, due to the loss of organic matter during pre-treatment stages in anaerobic digestion facilities. From an environmental point of view, the Life Cycle Assessment shows that the incineration scenario is the most favorable alternative for eight out of nine impact categories compared with the landfill scenario. The studied impact categories are Climate Change, Fossil depletion, Freshwater eutrophication, Marine eutrophication, Ozone depletion, Particulate matter formation, Photochemical oxidant formation, Terrestrial acidification and Water depletion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimizing the vermicomposting of organic wastes amended with inorganic materials for production of nutrient-rich organic fertilizers: a review.

PubMed

Mupambwa, Hupenyu Allan; Mnkeni, Pearson Nyari Stephano

2018-04-01

Vermicomposting is a bio-oxidative process that involves the action of mainly epigeic earthworm species and different micro-organisms to accelerate the biodegradation and stabilization of organic materials. There has been a growing realization that the process of vermicomposting can be used to greatly improve the fertilizer value of different organic materials, thus, creating an opportunity for their enhanced use as organic fertilizers in agriculture. The link between earthworms and micro-organisms creates a window of opportunity to optimize the vermi-degradation process for effective waste biodegradation, stabilization, and nutrient mineralization. In this review, we look at up-to-date research work that has been done on vermicomposting with the intention of highlighting research gaps on how further research can optimize vermi-degradation. Though several researchers have studied the vermicomposting process, critical parameters that drive this earthworm-microbe-driven process which are C/N and C/P ratios; substrate biodegradation fraction, earthworm species, and stocking density have yet to be adequately optimized. This review highlights that optimizing the vermicomposting process of composts amended with nutrient-rich inorganic materials such as fly ash and rock phosphate and inoculated with microbial inoculants can enable the development of commercially acceptable organic fertilizers, thus, improving their utilization in agriculture.

Microbial utilisation of natural organic wastes

NASA Astrophysics Data System (ADS)

Ilyin, V. K.; Smirnov, I. A.; Soldatov, P. E.; Korniushenkova, I. N.; Grinin, A. S.; Lykov, I. N.; Safronova, S. A.

2004-03-01

The waste management strategy for the future should meet the benefits of humanity safety, respect principals of planet ecology, and compatibility with other habitability systems. For these purpose the waste management technologies, relevant to application of the biodegradation properties of bacteria are of great value. The biological treatment method is based upon the biodegradation of organic substances by various microorganisms. The advantage of the biodegradation waste management in general: it allows to diminish the volume of organic wastes, the biological hazard of the wastes is controlled and this system may be compatible with the other systems. The objectives of our study were: to evaluate effectiveness of microbial biodegradation of non-pretreated substrate, to construct phneumoautomatic digester for organic wastes biodegradation and to study microbial characteristics of active sludge samples used as inoculi in biodegradation experiment. The technology of vegetable wastes treatment was elaborated in IBMP and BMSTU. For this purpose the special unit was created where the degradation process is activated by enforced reinvention of portions of elaborated biogas into digester. This technology allows to save energy normally used for electromechanical agitation and to create optimal environment for anaerobic bacteria growth. The investigations were performed on waste simulator, which imitates physical and chemical content of food wastes calculated basing on the data on food wastes of moderate Russian city. The volume of created experimental sample of digester is 40 l. The basic system elements of device are digesters, gas receiver, remover of drops and valve monitoring and thermal control system. In our testing we used natural food wastes to measure basic parameters and time of biodegradation process. The diminution rate of organic gained 76% from initial mass taking part within 9 days of fermentation. The biogas production achieved 46 l per 1 kg of substrate. The microbial studies of biodegradation process revealed following peculiarities: gradual quantitative increasing of Lactobacillus sp. (from 10 3 to 10 5 colony forming units (CFU) per ml), activation of Clostridia sp. (from 10 2 to 10 4 CFU/ml) and elimination of aerobic conventional pathogens ( Enterobacteriaceae sp., Protea sp., staphylococci). The obtained results allow to evaluate effectiveness of proposed technology and to determine the leading role of lactobacilli and clostridia in process of natural wastes biodegradation. Our further investigations shall further be concentrated on creation of artificial inoculi for launching of food wastes biodegradation. These inoculi will include active and adapted strains of clostridia and lactobacilli.

Solid recovered fuel production from biodegradable waste in grain processing industry.

PubMed

Kliopova, Irina; Staniskis, Jurgis Kazimieras; Petraskiene, Violeta

2013-04-01

Management of biodegradable waste is one of the most important environmental problems in the grain-processing industry since this waste cannot be dumped anymore due to legal requirements. Biodegradable waste is generated in each stage of grain processing, including the waste-water and air emissions treatment processes. Their management causes some environmental and financial problems. The majority of Lithuanian grain-processing enterprises own and operate composting sites, but in Lithuania the demand for compost is not given. This study focused on the analysis of the possibility of using biodegradable waste for the production of solid recovered fuel, as a local renewable fuel with the purpose of increasing environmental performance and decreasing the direct costs of grain processing. Experimental research with regard to a pilot grain-processing plant has proven that alternative fuel production will lead to minimizing of the volume of biodegradable waste by 75% and the volume of natural gas for heat energy production by 62%. Environmental indicators of grain processing, laboratory analysis of the chemical and physical characteristics of biodegradable waste, mass and energy balances of the solid recovered fuel production, environmental and economical benefits of the project are presented and discussed herein.

Martial recycling from renewable landfill and associated risks: A review.

PubMed

Ziyang, Lou; Luochun, Wang; Nanwen, Zhu; Youcai, Zhao

2015-07-01

Landfill is the dominant disposal choice for the non-classified waste, which results in the stockpile of materials after a long term stabilization process. A novel landfill, namely renewable landfill (RL), is developed and applied as a strategy to recycle the residual materials and reuse the land occupation, aim to reduce the inherent problems of large land occupied, materials wasted and long-term pollutants released in the conventional landfill. The principle means of RL is to accelerate the waste biodegradation process in the initial period, recover the various material resources disposal and extend the landfill volume for waste re-landfilling after waste stabilized. The residual material available and risk assessment, the methodology of landfill excavation, the potential utilization routes for different materials, and the reclamation options for the unsanitary landfill are proposed, and the integrated beneficial impacts are identified finally from the economic, social and environmental perspectives. RL could be draw as the future reservoirs for resource extraction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental performance of bio-based and biodegradable plastics: the road ahead.

PubMed

Lambert, Scott; Wagner, Martin

2017-11-13

Future plastic materials will be very different from those that are used today. The increasing importance of sustainability promotes the development of bio-based and biodegradable polymers, sometimes misleadingly referred to as 'bioplastics'. Because both terms imply "green" sources and "clean" removal, this paper aims at critically discussing the sometimes-conflicting terminology as well as renewable sources with a special focus on the degradation of these polymers in natural environments. With regard to the former we review innovations in feedstock development (e.g. microalgae and food wastes). In terms of the latter, we highlight the effects that polymer structure, additives, and environmental variables have on plastic biodegradability. We argue that the 'biodegradable' end-product does not necessarily degrade once emitted to the environment because chemical additives used to make them fit for purpose will increase the longevity. In the future, this trend may continue as the plastics industry also is expected to be a major user of nanocomposites. Overall, there is a need to assess the performance of polymer innovations in terms of their biodegradability especially under realistic waste management and environmental conditions, to avoid the unwanted release of plastic degradation products in receiving environments.

Mechanical-biological treatment: performance and potentials. An LCA of 8 MBT plants including waste characterization.

PubMed

Montejo, Cristina; Tonini, Davide; Márquez, María del Carmen; Astrup, Thomas Fruergaard

2013-10-15

In the endeavour of avoiding presence of biodegradable waste in landfills and increasing recycling, mechanical-biological treatment (MBT) plants have seen a significant increase in number and capacity in the last two decades. The aim of these plants is separating and stabilizing the quickly biodegradable fraction of the waste as well as recovering recyclables from mixed waste streams. In this study the environmental performance of eight MBT-based waste management scenarios in Spain was assessed by means of life cycle assessment. The focus was on the technical and environmental performance of the MBT plants. These widely differed in type of biological treatment and recovery efficiencies. The results indicated that the performance is strongly connected with energy and materials recovery efficiency. The recommendation for upgrading and/or commissioning of future plants is to optimize materials recovery through increased automation of the selection and to prioritize biogas-electricity production from the organic fraction over direct composting. The optimal strategy for refuse derived fuel (RDF) management depends upon the environmental compartment to be prioritized and the type of marginal electricity source in the system. It was estimated that, overall, up to ca. 180-190 kt CO2-eq. y(-1) may be saved by optimizing the MBT plants under assessment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Need for improvements in physical pretreatment of source-separated household food waste.

PubMed

Bernstad, A; Malmquist, L; Truedsson, C; la Cour Jansen, J

2013-03-01

The aim of the present study was to investigate the efficiency in physical pretreatment processes of source-separated solid organic household waste. The investigation of seventeen Swedish full-scale pretreatment facilities, currently receiving separately collected food waste from household for subsequent anaerobic digestion, shows that problems with the quality of produced biomass and high maintenance costs are common. Four full-scale physical pretreatment plants, three using screwpress technology and one using dispergation technology, were compared in relation to resource efficiency, losses of nitrogen and potential methane production from biodegradable matter as well as the ratio of unwanted materials in produced biomass intended for wet anaerobic digestion. Refuse generated in the processes represent 13-39% of TS in incoming wet waste. The methane yield from these fractions corresponds to 14-36Nm(3)/ton separately collected solid organic household waste. Also, 13-32% of N-tot in incoming food waste is found in refuse. Losses of both biodegradable material and nutrients were larger in the three facilities using screwpress technology compared to the facility using dispersion technology.(1) Thus, there are large potentials for increase of both the methane yield and nutrient recovery from separately collected solid organic household waste through increased efficiency in facilities for physical pretreatment. Improved pretreatment processes could thereby increase the overall environmental benefits from anaerobic digestion as a treatment alternative for solid organic household waste. Copyright © 2012 Elsevier Ltd. All rights reserved.

Microbial utilisation of natural organic wastes.

PubMed

Ilyin, V K; Smirnov, I A; Soldatov, P E; Korniushenkova, I N; Grinin, A S; Lykov, I N; Safronova, S A

2004-03-01

The waste management strategy for the future should meet the benefits of humanity safety, respect principals of planet ecology, and compatibility with other habitability systems. For these purpose the waste management technologies, relevant to application of the biodegradation properties of bacteria are of great value. The biological treatment method is based upon the biodegradation of organic substances by various microorganisms. The advantage of the biodegradation waste management in general: it allows to diminish the volume of organic wastes, the biological hazard of the wastes is controlled, and this system may be compatible with the other systems. The objectives of our study were: to evaluate effectiveness of microbial biodegradation of non-pretreated substrate, to construct phneumoautomatic digester for organic wastes biodegradation, and to study microbial characteristics of active sludge samples used as inoculi in biodegradation experiment. The technology of vegetable wastes treatment was elaborated in IBMP and BMSTU. For this purpose the special unit was created where the degradation process is activated by enforced reinvention of portions of elaborated biogas into digester. This technology allows to save energy normally used for electromechanical agitation and to create optimal environment for anaerobic bacteria growth. The investigations were performed on waste simulator, which imitates physical and chemical content of food wastes calculated basing on the data on food wastes of moderate Russian city. The volume of created experimental sample of digester is 40 l. The basic system elements of device are digesters, gas receiver, remover of drops and valve monitoring and thermal control system. In our testing we used natural food wastes to measure basic parameters and time of biodegradation process. The diminution rate of organic gained 76% from initial mass taking part within 9 days of fermentation. The biogas production achieved 46 l per 1 kg of substrate. The microbial studies of biodegradation process revealed following peculiarities: (i) gradual quantitative increasing of Lactobacillus sp. (from 10(3) to 10(5) colony forming units (CFU) per ml), (ii) activation of Clostridia sp. (from 10(2) to 10(4)CFU/ml), (iii) elimination of aerobic conventional pathogens (Enterobacteriaceae sp., Protea sp., staphylococci). The obtained results allow to evaluate effectiveness of proposed technology and to determine the leading role of lactobacilli and clostridia in process of natural wastes biodegradation. Our further investigations shall further be concentrated on creation of artificial inoculi for launching of food wastes biodegradation. These inoculi will include active and adapted strains of clostridia and lactobacilli. c2003 Elsevier Ltd. All rights reserved.

Biodegradation pattern of hydrocarbons from a fuel oil-type complex residue by an emulsifier-producing microbial consortium.

PubMed

Nievas, M L; Commendatore, M G; Esteves, J L; Bucalá, V

2008-06-15

The biodegradation of a hazardous waste (bilge waste), a fuel oil-type complex residue from normal ship operations, was studied in a batch bioreactor using a microbial consortium in seawater medium. Experiments with initial concentrations of 0.18 and 0.53% (v/v) of bilge waste were carried out. In order to study the biodegradation kinetics, the mass of n-alkanes, resolved hydrocarbons and unresolved complex mixture (UCM) hydrocarbons were assessed by gas chromatography (GC). Emulsification was detected in both experiments, possibly linked to the n-alkanes depletion, with differences in emulsification start times and extents according to the initial hydrocarbon concentration. Both facts influenced the hydrocarbon biodegradation kinetics. A sequential biodegradation of n-alkanes and UMC was found for the higher hydrocarbon content. Being the former growth associated, while UCM biodegradation was a non-growing process showing enzymatic-type biodegradation kinetics. For the lower hydrocarbon concentration, simultaneous biodegradation of n-alkanes and UMC were found before emulsification. Nevertheless, certain UCM biodegradation was observed after the medium emulsification. According to the observed kinetics, three main types of hydrocarbons (n-alkanes, biodegradable UCM and recalcitrant UCM) were found adequate to represent the multicomponent substrate (bilge waste) for future modelling of the biodegradation process.

Biodegradation of polyether-polyol-based polyurethane elastomeric films: influence of partial replacement of polyether polyol by biopolymers of renewable origin.

PubMed

Obruca, Stanislav; Marova, Ivana; Vojtova, Lucy

2011-07-01

In this work we investigated the degradation process ofpolyether-polyol-based polyurethane (PUR) elastomeric films in the presence of a mixed thermophilic culture as a model of a natural bacterial consortium. The presence of PUR material in cultivation medium resulted in delayed but intensive growth of the bacterial culture. The unusually long lag phase was caused by the release of unreacted polyether polyol and tin catalyst from the material. The lag phase was significantly shortened and the biodegradability of PUR materials was enhanced by partial replacement (10%) of polyether polyol with biopolymers (carboxymethyl cellulose, hydroxyethyl cellulose, acetyl cellulose and actylated starch). The process of material degradation consisted of two steps. First, the materials were mechanically disrupted and, second, the bacterial culture was able to utilize abiotic degradation products, which resulted in supported bacterial growth. Direct utilization of PUR by the bacterial culture was observed as well, but the bacterial culture contributed only slightly to the total mass losses. The only exception was PUR material modified by acetyl cellulose. In this case, direct biodegradation represented the major mechanism of material decomposition. Moreover, PUR material modified by acetyl cellulose did not tend to undergo abiotic degradation. In conclusion, the modification of PUR by proper biopolymers is a promising strategy for reducing potential negative effects of waste PUR materials on the environment and enhancing their biodegradability.

Oil uptake by plant-based sorbents and its biodegradation by their naturally associated microorganisms.

PubMed

Dashti, Narjes; Ali, Nedaa; Khanafer, Majida; Radwan, Samir S

2017-08-01

The plant waste-products, wheat straw, corn-cobs and sugarcane bagasse took up respectively, 190, 110 and 250% of their own weights crude oil. The same materials harbored respectively, 3.6 × 10 5 , 8.5 × 10 3 and 2.3 × 10 6  g -1  cells of hydrocarbonoclastic microorganisms, as determined by a culture-dependent method. The molecular, culture-independent analysis revealed that the three materials were associated with microbial communities comprising genera known for their hydrocarbonoclastic activity. In bench-scale experiments, inoculating oily media with samples of the individual waste products led to the biodegradation of 34.0-44.9% of the available oil after 8 months. Also plant-product samples, which had been used as oil sorbents lost 24.3-47.7% of their oil via their associated microorganisms, when kept moist for 8 months. In this way, it is easy to see that those waste products are capable of remediating spilled oil physically, and that their associated microbial communities can degrade it biologically. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical performance of biodegradable films intended for antimicrobial food packaging.

PubMed

Marcos, Begonya; Aymerich, Teresa; Monfort, Josep M; Garriga, Margarita

2010-10-01

Antimicrobial films were prepared by including enterocins to alginate, polyvinyl alcohol (PVOH), and zein films. The physical performance of the films was assessed by measuring color, microstructure (SEM), water vapor permeability (WVP), and tensile properties. All studied biopolymers showed poor WVP and limited tensile properties. PVOH showed the best performance exhibiting the lowest WVP values, higher tensile properties, and flexibility among studied biopolymers. SEM of antimicrobial films showed increased presence of voids and pores as a consequence of enterocin addition. However, changes in microstructure did not disturb WVP of films. Moreover, enterocin-containing films showed slight improvement compared to control films. Addition of enterocins to PVOH films had a plasticizing effect, by reducing its tensile strength and increasing the strain at break. The presence of enterocins had an important effect on tensile properties of zein films by significantly reducing its brittleness. Addition of enterocins, thus, proved not to disturb the physical performance of studied biopolymers. Development of new antimicrobial biodegradable packaging materials may contribute to improving food safety while reducing environmental impact derived from packaging waste. Practical Application: Development of new antimicrobial biodegradable packaging materials may contribute to improving food safety while reducing environmental impact derived from packaging waste.

Assessment of multiple geophysical techniques for the characterization of municipal waste deposit sites

NASA Astrophysics Data System (ADS)

Gaël, Dumont; Tanguy, Robert; Nicolas, Marck; Frédéric, Nguyen

2017-10-01

In this study, we tested the ability of geophysical methods to characterize a large technical landfill installed in a former sand quarry. The geophysical surveys specifically aimed at delimitating the deposit site horizontal extension, at estimating its thickness and at characterizing the waste material composition (the moisture content in the present case). The site delimitation was conducted with electromagnetic (in-phase and out-of-phase) and magnetic (vertical gradient and total field) methods that clearly showed the transition between the waste deposit and the host formation. Regarding waste deposit thickness evaluation, electrical resistivity tomography appeared inefficient on this particularly thick deposit site. Thus, we propose a combination of horizontal to vertical noise spectral ratio (HVNSR) and multichannel analysis of the surface waves (MASW), which successfully determined the approximate waste deposit thickness in our test landfill. However, ERT appeared to be an appropriate tool to characterize the moisture content of the waste, which is of prior information for the organic waste biodegradation process. The global multi-scale and multi-method geophysical survey offers precious information for site rehabilitation studies, water content mitigation processes for enhanced biodegradation or landfill mining operation planning.

Bio-inspired organic field effect transistors

NASA Astrophysics Data System (ADS)

Irimia-Vladu, Mihai; Troshin, Pavel A.; Schwabegger, Günther; Bodea, Marius; Schwödiauer, Reinhard; Fergus, Jeffrey W.; Razumov, Vladimir; Bauer, Siegfried; Sariciftci, Niyazi Serdar

2010-08-01

Two major concerns in the world nowadays are the plastic consumption and waste. Because to the economic growth and the incessant demand of plastics in developing countries, plastics consumption is projected to increase by a factor of two to three during the actual decade1. As an intuitive example, the amount of municipal solid waste (estimated per person per year) averages ~440 kg for China, ~550 kg for the European Union and ~790 kg for the United States, with almost 50% of the waste being electronic products and plastics1,2. Green technology based on biodegradable/compostable materials is perceived as an ultimate goal for solving waste problems. Currently there are numerous efforts for producing compostable plastic materials for applications in daily life products, such as plastic bags and disposable dishware. When such low-end products are fabricated with compostable materials, electronics included in such goods should be also based on materials that are easily compostable.

Archaeal community structure in leachate and solid waste is correlated to methane generation and volume reduction during biodegradation of municipal solid waste.

PubMed

Fei, Xunchang; Zekkos, Dimitrios; Raskin, Lutgarde

2015-02-01

Duplicate carefully-characterized municipal solid waste (MSW) specimens were reconstituted with waste constituents obtained from a MSW landfill and biodegraded in large-scale landfill simulators for about a year. Repeatability and relationships between changes in physical, chemical, and microbial characteristics taking place during the biodegradation process were evaluated. Parameters such as rate of change of soluble chemical oxygen demand in the leachate (rsCOD), rate of methane generation (rCH4), rate of specimen volume reduction (rVt), DNA concentration in the leachate, and archaeal community structures in the leachate and solid waste were monitored during operation. The DNA concentration in the leachate was correlated to rCH4 and rVt. The rCH4 was related to rsCOD and rVt when waste biodegradation was intensive. The structures of archaeal communities in the leachate and solid waste of both simulators were very similar and Methanobacteriaceae were the dominant archaeal family throughout the testing period. Monitoring the chemical and microbial characteristics of the leachate was informative of the biodegradation process and volume reduction in the simulators, suggesting that leachate monitoring could be informative of the extent of biodegradation in a full-scale landfill. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biogeochemical Investigations to Evaluate the Performance of the Waste Isolation Pilot Plant (WIPP) (Invited)

NASA Astrophysics Data System (ADS)

Gillow, J. B.

2009-12-01

The Waste Isolation Pilot Plant (WIPP) is a U.S. Department of Energy facility located in southeastern New Mexico, approximately 655 m (2150 ft.) below ground surface in a bedded salt, Permian evaporite formation. This mined geologic repository has been receiving transuranic (TRU) waste from defense-related and environmental-management activities since March 1999. TRU waste contains alpha-emitting transuranic nuclides with half-lives greater than twenty years at concentrations greater than 100 nCi/gram. These actinide-contaminated wastes were generated from nuclear-weapons production and related processing activities. They include various organics, adsorbed liquids, sludges, cellulosics, plastics, rubber, and a variety of metals and cemented materials. An extensive set of investigations were performed to establish the basis for TRU waste disposal at WIPP and to support initial certification from the U.S. Environmental Protection Agency. A significant element of the conceptual geochemical model for WIPP is the microbiologically-driven reactions leading to biodegradation of organic constituents in TRU wastes, as well as interactions with actinides present in the waste. This presentation will discuss the biogeochemical investigations that were performed to evaluate microbiological activity at WIPP, including studies of gas generation due to biodegradation of cellulose, plastic, and rubber materials and actinide-microbe interactions leading to changes in actinide chemical speciation. Highlights of this work are discussed here. Cellulose biodegradation in salt-brine systems results in the generation of carbon dioxide and hydrogen, and aqueous fermentation products (low molecular weight organic acids). Hypersaline brine can limit the range of microbial metabolic pathways, due to the energetic stresses of maintaining osmotic balance compatible with metabolic processes. Methanogenesis yields the lowest free energy per mole of carbon and as such is often not detected in microorganisms that thrive in salt-brine environments (halophilic bacteria). However, laboratory tests performed over a period of 10 years demonstrated the production of methane gas from cellulose metabolism. Studies of actinide-microbe interactions revealed the bioaccumulation of uranium in phosphate-rich intracellular granules. These studies advanced the understanding of the metabolism of bacteria in salt-brine systems and the influence of halophilic microbiological activity on WIPP geochemistry.

Breakdown of plastics and polymers by microorganisms.

PubMed

Kawai, F

1995-01-01

The interest in environmental issues is still growing and there are increasing demands to develop materials which do not burden the environment significantly. Awareness of the waste problem and its impact on the environment has awakened new interest in the area of degradable polymers. Biodegradation is necessary for water-soluble or water-miscible polymers because they eventually enter streams which can neither be recycled nor incinerated. It is important to consider the microbial degradation of natural and synthetic polymers in order to understand what is necessary for biodegradation and the mechanisms involved. This requires both biochemical insight and understanding of the interactions between materials and microorganisms. It is now widely requested that polymeric materials come from renewable resources instead of petrochemical sources. The microbial production of polymeric and oligomeric materials is also described.

Reclamation with Recovery of Radionuclides and Toxic Metals from Contaminated Materials, Soils, and Wastes

NASA Technical Reports Server (NTRS)

Francis, A. J.; Dodge, C. J.

1993-01-01

A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites. In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and actinides, and may involve formation of a bidentate, tridentate, binuclear, or polynuclear complex species. The extract containing radionuclide/metal complex is then subjected to microbiological degradation followed by photochemical degradation under aerobic conditions. Several metal citrate complexes are biodegraded, and the metals are recovered in a concentrated form with the bacterial biomass. Uranium forms binuclear complex with citric acid and is not biodegraded. The supernatant containing uranium citrate complex is separated and upon exposure to light, undergoes rapid degradation resulting in the formation of an insoluble, stable polymeric form of uranium. Uranium is recovered as a precipitate (polyuranate) in a concentrated form for recycling or for appropriate disposal. This treatment process, unlike others which use caustic reagents, does not create additional hazardous wastes for disposal and causes little damage to soil which can then be returned to normal use.

Bio-generated succinic acid esters in lubricant applications

USDA-ARS?s Scientific Manuscript database

Succinic acid is a biodegradable natural product mainly produced industrially from petroleum-based maleic anhydride. It is a platform material for many industrial chemicals. Recent work has generated succinic acid by fermentation of Physaria fendleri press cake, an otherwise waste agricultural bypro...

BIODEGRADATIVE ANALYSIS OF MUNICIPAL SOLID WASTE IN LABORATORY-SCALE LANDFILLS

EPA Science Inventory

The report gives results of research to characterize the anaerobic biodegradability of the major biodegradable components of municipal solid waste (MSW). Tests were conducted in quadruplicate in 2-L reactors operated to obtain maximum yields. Measured methane (CH4) yields for gra...

Purification of liquid products of cotton wipes biotransformation with the aid of Trichoderma viridae in orbital flight

NASA Astrophysics Data System (ADS)

Viacheslav, Ilyin; Korshunov, Denis

Recovery of various organic wastes in space flight is an actual problem of modern astronautics and future interplanetary missions. Currently, organic waste are incinerated in the dense layers of the Earth's atmosphere in cargo containers. However, this method of anthropogenic waste treatment is not environmentally compatible with future interplanetary missions, and is not suitable due to planetary quarantine requirements. Furthermore, the maintaining of a closed ecosystem in spaceship is considered as one of the main ways of ensuring the food and air crew in the long term fully autonomous space expedition. Such isolated ecosystem is not conceivable without biotransformation of organic waste. In this regard, currently new ways of recycling organic waste are currently developed. The most promising method is a method for processing organic waste using thermophilic anaerobic microbial communities.However, the products of anaerobic fermentation of solid organic materials contain significant amounts of organic impurities, which often give them sour pH. This presents a significant problem because it does not allow to use this fluid as process water without pretreatment. Fermentation products - alcohols, volatile fatty acids other carbonaceous substances must be withdrawn.One way to solve this problem may be the use of microorganisms biodestructors for recycling organic impurities in the products of anaerobic biodegradation Under the proposed approach, the metabolic products (having acidic pH) of primary biotransformation of solid organic materials are used as media for the cultivation of fungi. Thus, cellulosic wastes are recycled in two successive stages. The aim of this work was to test the effectiveness of post-treatment liquid products of biodegradation of hygienic cotton wipes (common type of waste on the ISS) by the fungus Trichoderma viridae under orbital flight. The study was conducted onboard biosatellite Bion -M1, where was placed a bioreactor, designed to carry out the fermentation in space flight. For aerobic post-treatment of substrates remaining after biodegradation of cotton wipe there was selected a strain of the fungus Trihoderma viridae, able to grow at a slightly acid environment , and to bring the pH to neutral values. Bioreactor working volume of 40 ml, where 20 ml of liquid subjected to post-treatment was placed. Strain Trihoderma viridae, isolated from ISS environment, showed steady growth in terms identical to those of pre- cultivation. Efficiency of purification was assessed using the method of gas chromatography-mass spectrometry comparing the amount and concentration of the volatile organic compounds in the samples. It turned out that the number of compounds detected in the flight sample almost halved compared to the original sample obtained after biodegradation gauze anaerobic bacteria. The total concentration of volatile impurities dropped 6 times. Thus, despite the limited resource of oxygen, due to lack of aeration in the bioreactor strain Trihoderma viridae demonstrated the ability to perform aerobic purification of substrate obtained after anaerobic biodegradation of cotton wipes under orbital flight.

Microwave Absorption Characteristics of Tire

NASA Astrophysics Data System (ADS)

Zhang, Yuzhe; Hwang, Jiann-Yang; Peng, Zhiwei; Andriese, Matthew; Li, Bowen; Huang, Xiaodi; Wang, Xinli

The recycling of waste tires has been a big environmental problem. About 280 million waste tires are produced annually in the United States and more than 2 billion tires are stockpiled, which cause fire hazards and health issues. Tire rubbers are insoluble elastic high polymer materials. They are not biodegradable and may take hundreds of years to decompose in the natural environment. Microwave irradiation can be a thermal processing method for the decomposition of tire rubbers. In this study, the microwave absorption properties of waste tire at various temperatures are characterized to determine the conditions favorable for the microwave heating of waste tires.

Development of more friendly food packaging materials base on polypropylene through blending with polylacticacid

NASA Astrophysics Data System (ADS)

Setiawan, Achmad Hanafi; Aulia, Fauzan

2017-01-01

The commonly food packaging materials today is used a thin layer plastic or film, which is made of a synthetic polymer, such as polypropylene (PP). However, the use of these polymers has a negative impact on the environment, because the synthetic polymer is difficult to degrade naturally by the biotic components such as micro-organisms decomposers and abiotic components such as the sunshine. The use of the biodegradable polymeric material will reduce the use of synthetic polymer products, thereby reducing plastic waste pollution at relatively low cost, it is expected to produce positive effects both for the environment and in terms of economy. PLA is a biodegradable polymer that can be substituted totally or partially to synthetic polymers as far as could fulfill the main function of packaging in the protection and preservation of food. Increasing PLA content in polypropylene blend will affect to the increasing in its water absorption and also its biodegradable. 20% PLA may the optimum composition of poly-blend for food packaging.

Recent advances in yeast cell-surface display technologies for waste biorefineries.

PubMed

Liu, Zhuo; Ho, Shih-Hsin; Hasunuma, Tomohisa; Chang, Jo-Shu; Ren, Nan-Qi; Kondo, Akihiko

2016-09-01

Waste biorefinery aims to maximize the output of value-added products from various artificial/agricultural wastes by using integrated bioprocesses. To make waste biorefinery economically feasible, it is thus necessary to develop a low-cost, environment-friendly technique to perform simultaneous biodegradation and bioconversion of waste materials. Cell-surface display engineering is a novel, cost-effective technique that can auto-immobilize proteins on the cell exterior of microorganisms, and has been applied for use with waste biofinery. Through tethering different enzymes (e.g., cellulase, lipase, and protease) or metal-binding peptides on cell surfaces, various yeast strains can effectively produce biofuels and biochemicals from sugar/protein-rich waste materials, catalyze waste oils into biodiesels, or retrieve heavy metals from wastewater. This review critically summarizes recent applications of yeast cell-surface display on various types of waste biorefineries, highlighting its potential and future challenges with regard to commercializing this technology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potential for polyhydroxyalkanoate production on German or European municipal waste water treatment plants.

PubMed

Pittmann, T; Steinmetz, H

2016-08-01

Biopolymers, which are made of renewable raw materials and/or biodegradable residual materials present a possible alternative to common plastic. A potential analysis, based on experimental results in laboratory scale and detailed data from German waste water treatment plants, showed that the theoretically possible production of biopolymers in Germany amounts to more than 20% of the 2015 worldwide biopolymer production. In addition a profound estimation regarding all European Union member states showed that theoretically about 115% of the actual worldwide biopolymer production could be produced on European waste water treatment plants. With an upgraded biopolymer production and a theoretically reachable biopolymer proportion of around 60% of the cell dry weight a total of 1,794,656tPHAa or approximately 236% of today's biopolymer production could be produced on waste water treatment plants in the European Union, using primary sludge as raw material only. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biodegradation of polyester polyurethane by Aspergillus tubingensis.

PubMed

Khan, Sehroon; Nadir, Sadia; Shah, Zia Ullah; Shah, Aamer Ali; Karunarathna, Samantha C; Xu, Jianchu; Khan, Afsar; Munir, Shahzad; Hasan, Fariha

2017-06-01

The xenobiotic nature and lack of degradability of polymeric materials has resulted in vast levels of environmental pollution and numerous health hazards. Different strategies have been developed and still more research is being in progress to reduce the impact of these polymeric materials. This work aimed to isolate and characterize polyester polyurethane (PU) degrading fungi from the soil of a general city waste disposal site in Islamabad, Pakistan. A novel PU degrading fungus was isolated from soil and identified as Aspergillus tubingensis on the basis of colony morphology, macro- and micro-morphology, molecular and phylogenetic analyses. The PU degrading ability of the fungus was tested in three different ways in the presence of 2% glucose: (a) on SDA agar plate, (b) in liquid MSM, and (c) after burial in soil. Our results indicated that this strain of A. tubingensis was capable of degrading PU. Using scanning electron microscopy (SEM), we were able to visually confirm that the mycelium of A. tubingensis colonized the PU material, causing surface degradation and scarring. The formation or breakage of chemical bonds during the biodegradation process of PU was confirmed using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy. The biodegradation of PU was higher when plate culture method was employed, followed by the liquid culture method and soil burial technique. Notably, after two months in liquid medium, the PU film was totally degraded into smaller pieces. Based on a comprehensive literature search, it can be stated that this is the first report showing A. tubingensis capable of degrading PU. This work provides insight into the role of A. tubingensis towards solving the dilemma of PU wastes through biodegradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Carbon-rich wastes as feedstocks for biodegradable polymer (polyhydroxyalkanoate) production using bacteria.

PubMed

Nikodinovic-Runic, Jasmina; Guzik, Maciej; Kenny, Shane T; Babu, Ramesh; Werker, Alan; O Connor, Kevin E

2013-01-01

Research into the production of biodegradable polymers has been driven by vision for the most part from changes in policy, in Europe and America. These policies have their origins in the Brundtland Report of 1987, which provides a platform for a more sustainable society. Biodegradable polymers are part of the emerging portfolio of renewable raw materials seeking to deliver environmental, social, and economic benefits. Polyhydroxyalkanoates (PHAs) are naturally-occurring biodegradable-polyesters accumulated by bacteria usually in response to inorganic nutrient limitation in the presence of excess carbon. Most of the early research into PHA accumulation and technology development for industrial-scale production was undertaken using virgin starting materials. For example, polyhydroxybutyrate and copolymers such as polyhydroxybutyrate-co-valerate are produced today at industrial scale from corn-derived glucose. However, in recent years, research has been undertaken to convert domestic and industrial wastes to PHA. These wastes in today's context are residuals seen by a growing body of stakeholders as platform resources for a biobased society. In the present review, we consider residuals from food, plastic, forest and lignocellulosic, and biodiesel manufacturing (glycerol). Thus, this review seeks to gain perspective of opportunities from literature reporting the production of PHA from carbon-rich residuals as feedstocks. A discussion on approaches and context for PHA production with reference to pure- and mixed-culture technologies is provided. Literature reports advocate results of the promise of waste conversion to PHA. However, the vast majority of studies on waste to PHA is at laboratory scale. The questions of surmounting the technical and political hurdles to industrialization are generally left unanswered. There are a limited number of studies that have progressed into fermentors and a dearth of pilot-scale demonstration. A number of fermentation studies show that biomass and PHA productivity can be increased, and sometimes dramatically, in a fermentor. The relevant application-specific properties of the polymers from the wastes studied and the effect of altered-waste composition on polymer properties are generally not well reported and would greatly benefit the progress of the research as high productivity is of limited value without the context of requisite case-specific polymer properties. The proposed use of a waste residual is advantageous from a life cycle viewpoint as it removes the direct or indirect effect of PHA production on land usage and food production. However, the question, of how economic drivers will promote or hinder advancements to demonstration scale, when wastes generally become understood as resources for a biobased society, hangs today in the balance due to a lack of shared vision and the legacy of mistakes made with first generation bioproducts. Copyright © 2013 Elsevier Inc. All rights reserved.

An empirical model for prediction of household solid waste generation rate - A case study of Dhanbad, India.

PubMed

Kumar, Atul; Samadder, S R

2017-10-01

Accurate prediction of the quantity of household solid waste generation is very much essential for effective management of municipal solid waste (MSW). In actual practice, modelling methods are often found useful for precise prediction of MSW generation rate. In this study, two models have been proposed that established the relationships between the household solid waste generation rate and the socioeconomic parameters, such as household size, total family income, education, occupation and fuel used in the kitchen. Multiple linear regression technique was applied to develop the two models, one for the prediction of biodegradable MSW generation rate and the other for non-biodegradable MSW generation rate for individual households of the city Dhanbad, India. The results of the two models showed that the coefficient of determinations (R 2 ) were 0.782 for biodegradable waste generation rate and 0.676 for non-biodegradable waste generation rate using the selected independent variables. The accuracy tests of the developed models showed convincing results, as the predicted values were very close to the observed values. Validation of the developed models with a new set of data indicated a good fit for actual prediction purpose with predicted R 2 values of 0.76 and 0.64 for biodegradable and non-biodegradable MSW generation rate respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 98.464 - Monitoring and QA/QC requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Determine DOC value of a waste stream by either using at least a 60-day anaerobic biodegradation test as... biodegradation test and determine the DOC value of a waste stream following the procedures and requirements in...-based standards organization to conduct a minimum of a 60-day anaerobic biodegradation test. Consensus...

Microbial desalination cell for enhanced biodegradation of waste engine oil using a novel bacterial strain Bacillus subtilis moh3.

PubMed

Sabina, K; Fayidh, Mohammed A; Archana, G; Sivarajan, M; Babuskin, S; Babu, P Azhagu Saravana; Radha, K Krishnan; Sukumar, M

2014-01-01

Microbial desalination cell (MDC) is a bioelectrochemical system developed recently from microbial fuel cells (MFCs), for producing green energy from organic wastes along with desalination of saltwater. MDC is proved to be a better performer than MFC in terms of power output and chemical oxygen demand removal, with desalination as an additional feature. This study investigates the application potential of MDC for integrated biodegradation of waste engine oil. This study showed, for the first time, that waste engine oil could be used as an organic substrate in MDC, achieving biodegradation of engine oil along with considerable desalination and power production. Utilization of these wastes in MDC can protect the environment from waste engine oil contamination. Indigenous oil-degrading bacteria were isolated and identified from engine oil contaminated sludge. Degradation of waste engine oil by these novel isolates was studied in batch cultures and optimized the growth conditions. The same cultures when used in MDC, gave enhanced biodegradation (70.1 +/- 0.5%) along with desalination (68.3 +/- 0.6%) and power production (3.1 +/- 0.3 mW/m2). Fourier transform-infrared spectroscopy and gas chromatography-mass spectrometry analyses were performed to characterize the degradation metabolites in the anolyte of MDC which clearly indicated the biodegradation of long chain, branched and cyclic hydrocarbons present in waste engine oil.

Fractions and biodegradability of dissolved organic matter derived from different composts.

PubMed

Wei, Zimin; Zhang, Xu; Wei, Yuquan; Wen, Xin; Shi, Jianhong; Wu, Junqiu; Zhao, Yue; Xi, Beidou

2014-06-01

An experiment was conducted to determine the fractions of molecular weights (MW) and the biodegradability of dissolved organic matter (DOM) in mature composts derived from dairy cattle manure (DCM), kitchen waste (KW), cabbage waste (CW), tomato stem waste (TSW), municipal solid waste (MSW), green waste (GW), chicken manure (CM), sludge (S), and mushroom culture waste (MCW). There were distinct differences in the concentration and MW fractions of DOM, and the two measures were correlated. Fraction MW>5kDa was the major component of DOM in all mature composts. Determined 5day biochemical oxygen demand (BOD5) of DOM was correlated to the concentration of DOM and all MW fractions except MW>5kDa, indicating that the biodegradability of DOM was a function of the content and proportion of fraction MW<5kDa. This study suggests that the amount and distribution of low MW fractions affect DOM biodegradability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Processing and characterization of solid and microcellular biobased and biodegradable PHBV-based polymer blends and composites

NASA Astrophysics Data System (ADS)

Javadi, Alireza

Petroleum-based polymers have made a significant contribution to human society due to their extraordinary adaptability and processability. However, due to the wide-spread application of plastics over the past few decades, there are growing concerns over depleting fossil resources and the undesirable environmental impact of plastics. Most of the petroleum-based plastics are non-biodegradable and thus will be disposed in landfills. Inappropriate disposal of plastics may also become a potential threat to the environment. Many approaches, such as efficient plastics waste management and replacing petroleum-based plastics with biodegradable materials obtained from renewable resources, have been put forth to overcome these problems. Plastics waste management is at its beginning stages of development which is also more expensive than expected. Thus, there is a growing interest in developing sustainable biobased and biodegradable materials produced from renewable resources such as plants and crops, which can offer comparable performance with additional advantages, such as biodegradability, biocompatibility, and reducing the carbon footprint. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is one of the most promising biobased and biodegradable polymers, In fact many petroleum based polymers such as poly(propylene) (PP) can be potentially replaced by PHBV because of the similarity in their properties. Despite PHBV's attractive properties, there are many drawbacks such as high cost, brittleness, and thermal instability, which hamper the widespread usage of this specific polymer. The goals of this study are to investigate various strategies to address these drawbacks, including blending with other biodegradable polymers such as poly (butylene adipate-coterephthalate) (PBAT) or fillers (e.g., coir fiber, recycled wood fiber, and nanofillers) and use of novel processing technologies such as microcellular injection molding technique. Microcellular injection molding technique will not only reduce cost but also improve processability due to the use of supercritical fluid. Various material properties of the solid (without the foaming agent) and microcellular components (with foaming agent) made of PHBV-based polymer blends or composites were investigated including static mechanical properties (tensile testing), dynamic mechanical properties (dynamic mechanical analysis), thermal properties (differential scanning calorimetry and thermo gravimetric analysis), crystallinity(wide angle X-ray scattering analysis), and morphology (scanning electron microscopy and transmission electron microscopy). The composition-processing-structure-property relationship of these solid and microcellular components were established.

Activated sludge is a potential source for production of biodegradable plastics from wastewater.

PubMed

Khardenavis, A; Guha, P K; Kumar, M S; Mudliar, S N; Chakrabarti, T

2005-05-01

Increased utilization of synthetic plastics caused severe environmental pollution due to their non-biodegradable nature. In the search for environmentally friendly materials to substitute for conventional plastics, different biodegradable plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of biodegradable plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon: nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to optimize the carbon: nitrogen ratios using acetic acid and DAHP. A maximum of 65.84% (w/w) P(3HB) production was obtained at C/N ratio of 50 within 96 hours of incubation.

Management of soybean oil refinery wastes through recycling them for producing biosurfactant using Pseudomonas aeruginosa MR01.

PubMed

Partovi, Maryam; Lotfabad, Tayebe Bagheri; Roostaazad, Reza; Bahmaei, Manochehr; Tayyebi, Shokoufe

2013-06-01

Biosurfactant production through a fermentation process involving the biodegradation of soybean oil refining wastes was studied. Pseudomonas aeruginosa MR01 was able to produce extracellular biosurfactant when it was cultured in three soybean oil refinement wastes; acid oil, deodorizer distillate and soapstock, at different carbon to nitrogen ratios. Subsequent fermentation kinetics in the three types of waste culture were also investigated and compared with kinetic behavior in soybean oil medium. Biodegradation of wastes, biosurfactant production, biomass growth, nitrate consumption and the number of colony forming units were detected in four proposed media, at specified time intervals. Unexpectedly, wastes could stimulate the biodegradation activity of MR01 bacterial cells and thus biosurfactant synthesis beyond that of the refined soybean oil. This is evident from higher yields of biodegradation and production, as revealed in the waste cultures (Ydeg|(Soybean oil) = 53.9 % < Ydeg|(wastes) and YP/S|(wastes) > YP/S|(Soybean oil) = 0.31 g g(-1), respectively). Although production yields were approximately the same in the three waste cultures (YP/S|(wastes) =/~ 0.5 g g(-1)), microbial activity resulted in higher yields of biodegradation (96.5 ± 1.13 %), maximum specific growth rate (μ max = 0.26 ± 0.02 h(-1)), and biosurfactant purity (89.6 %) with a productivity of 14.55 ± 1.10 g l(-1), during the bioconversion of soapstock into biosurfactant. Consequently, applying soybean oil soapstock as a substrate for the production of biosurfactant with commercial value has the potential to provide a combination of economical production with environmental protection through the biosynthesis of an environmentally friendly (green) compound and reduction of waste load entering the environment. Moreover, this work inferred spectrophotometry as an easy method to detect rhamnolipids in the biosurfactant products.

Exploitation of Food Industry Waste for High-Value Products.

PubMed

Ravindran, Rajeev; Jaiswal, Amit K

2016-01-01

A growing global population leads to an increasing demand for food production and the processing industry associated with it and consequently the generation of large amounts of food waste. This problem is intensified due to slow progress in the development of effective waste management strategies and measures for the proper treatment and disposal of waste. Food waste is a reservoir of complex carbohydrates, proteins, lipids, and nutraceuticals and can form the raw materials for commercially important metabolites. The current legislation on food waste treatment prioritises the prevention of waste generation and least emphasises disposal. Recent valorisation studies for food supply chain waste opens avenues to the production of biofuels, enzymes, bioactive compounds, biodegradable plastics, and nanoparticles among many other molecules. Copyright © 2015 Elsevier Ltd. All rights reserved.

The valorization of the plastic waste to the rheological characteristics of bituminous mixtures

NASA Astrophysics Data System (ADS)

Boucherba, Mohammed; Kriker, Abdelouahed; Kebaili, Nabil

2017-02-01

The valorization of materials used at the end of the cycle currently constitutes one of the major challenges for the state for the safeguarding of the environment. Indeed, plastic waste from their obstruction and weak biodegradability often constitutes a threat for health, nature and the environment. The present study treats a mining method and valorization of these wastes in the road, where this waste is incorporated in the pure bitumen of asphalt concretes using the Dry process. The vital objective of this work is to see their impact on the mechanical behavior of these concretes using the Marshall Test and NAT.

Waste cotton as a biodegradable mulching material for transplanted watermelon and cantaloupe production

USDA-ARS?s Scientific Manuscript database

Low-density polyethylene (LDPE) mulch is commonly used in transplanted vegetable crop production in the southeastern U. S. Cantaloupe and watermelon growers use a system of hybrid transplants, grown on narrow LDPE mulch-covered seedbeds with overhead irrigation, and use the mulch cover for only one...

Using dairy ingredients to produce edible films and biodegradable packaging materials

USDA-ARS?s Scientific Manuscript database

Food packaging is comprised of multi-layers of films which are thin continuous sheets of synthetic polymers. Recently, major food retailers and consumers have become concerned about the waste that packaging generates and the scarce natural resources and energy used in its manufacture. They are deman...

The design and fabrication of a prototype trash compacting unit. [for long duration space missions

NASA Technical Reports Server (NTRS)

1973-01-01

A prototype trash compactor, that is compatible with the anticipated requirements of future long-term space missions, is described. Preliminary problem definition studies were conducted to identify typical types and quantities of waste materials to be expected from a typical mission. Bench-scale compaction tests were then conducted on typical waste materials to determine force/compaction curves. These data were used to design a boilerplate compactor that was fabricated to prove the feasibility of the basic design concept. A final design was then prepared from which the deliverable unit was fabricated. Design concepts are presented for suggested further development of the compactor, including a version that is capable of handling wet biodegradable wastes.

Quantification of parameters influencing methane generation due to biodegradation of municipal solid waste in landfills and laboratory experiments.

PubMed

Fei, Xunchang; Zekkos, Dimitrios; Raskin, Lutgarde

2016-09-01

The energy conversion potential of municipal solid waste (MSW) disposed of in landfills remains largely untapped because of the slow and variable rate of biogas generation, delayed and inefficient biogas collection, leakage of biogas, and landfill practices and infrastructure that are not geared toward energy recovery. A database consisting of methane (CH4) generation data, the major constituent of biogas, from 49 laboratory experiments and field monitoring data from 57 landfills was developed. Three CH4 generation parameters, i.e., waste decay rate (k), CH4 generation potential (L0), and time until maximum CH4 generation rate (tmax), were calculated for each dataset using U.S. EPA's Landfill Gas Emission Model (LandGEM). Factors influencing the derived parameters in laboratory experiments and landfills were investigated using multi-linear regression analysis. Total weight of waste (W) was correlated with biodegradation conditions through a ranked classification scheme. k increased with increasing percentage of readily biodegradable waste (Br0 (%)) and waste temperature, and reduced with increasing W, an indicator of less favorable biodegradation conditions. The values of k obtained in the laboratory were commonly significantly higher than those in landfills and those recommended by LandGEM. The mean value of L0 was 98 and 88L CH4/kg waste for laboratory and field studies, respectively, but was significantly affected by waste composition with ranges from 10 to 300L CH4/kg. tmax increased with increasing percentage of biodegradable waste (B0) and W. The values of tmax in landfills were higher than those in laboratory experiments or those based on LandGEM's recommended parameters. Enhancing biodegradation conditions in landfill cells has a greater impact on improving k and tmax than increasing B0. Optimizing the B0 and Br0 values of landfilled waste increases L0 and reduces tmax. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biofiltration kinetics for volatile organic compounds (VOCs) and development of a structure-biodegradability relationship

DOE Office of Scientific and Technical Information (OSTI.GOV)

Govind, R.; Wang, Z.; Bishop, D.F.

1997-12-31

In recent years, regulation of hazardous air pollutants under the Clean Air Act and its amendments, has emerged as a major environmental issue. Major sources of volatile organic compounds (VOCs) in air are chemical production plants, manufacturing sites using common solvents, combustion sources, and waste treatment operations, such as waste water treatment plants, vacuum extraction of contaminated soils, and ground water stripping operations. Biofiltration is an emerging technology for treatment of biodegradable volatile organic compounds (VOCs) present in air. In biofiltration, the contaminants are contacted with active microorganisms present either in naturally bioactive materials, such as soil, peat, compost, etc.,more » or immobilized on an inactive support media. Design of biofilters requires information on biodegradation kinetics which controls biofilter size. In this paper, an experimental microbiofilter system is presented which can be used to measure biofiltration kinetics for any volatile organic compound. A mathematical model is used to derive the Monod biokinetic parameters from the experimental data. Finally, a structure-bioactivity relationship is derived for estimating the biofiltration biokinetic parameters for a variety of VOCs.« less

A review of the technological solutions for the treatment of oily sludges from petroleum refineries.

PubMed

da Silva, Leonardo Jordão; Alves, Flávia Chaves; de França, Francisca Pessôa

2012-10-01

The activities of the oil industry have several impacts on the environment due to the large amounts of oily wastes that are generated. The oily sludges are a semi-solid material composed by a mixture of clay, silica and iron oxides contaminated with oil, produced water and the chemicals used in the production of oil. Nowadays both the treatment and management of these waste materials is essential to promote sustainable management of exploration and exploitation of natural resources. Biological, physical and chemical processes can be used to reduce environmental contamination by petroleum hydrocarbons to acceptable levels. The choice of treatment method depends on the physical and chemical properties of the waste as well as the availability of facilities to process these wastes. Literature provides some operations for treatment of oily sludges, such as landfilling, incineration, co-processing in clinkerization furnaces, microwave liquefaction, centrifugation, destructive distillation, thermal plasma, low-temperature conversion, incorporation in ceramic materials, development of impermeable materials, encapsulation and biodegradation in land farming, biopiles and bioreactors. The management of the technology to be applied for the treatment of oily wastes is essential to promote proper environmental management, and provide alternative methods to reduce, reuse and recycle the wastes.

Food loss and waste management in Turkey.

PubMed

Salihoglu, Guray; Salihoglu, Nezih Kamil; Ucaroglu, Selnur; Banar, Mufide

2018-01-01

Food waste can be an environmental and economic problem if not managed properly but it can meet various demands of a country if it is considered as a resource. The purpose of this report is to review the existing state of the field in Turkey and identify the potential of food waste as a resource. Food loss and waste (FLW) was examined throughout the food supply chain (FSC) and quantified using the FAO model. Edible FLW was estimated to be approximately 26milliontons/year. The amount of biodegradable waste was estimated based on waste statistics and research conducted on household food waste in Turkey. The total amount of biodegradable waste was found to be approximately 20milliontons/year, where more than 8.6milliontons/year of this waste is FLW from distribution and consumption in the FSC. Options for the end-of-life management of biodegradable wastes are also discussed in this review article. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spectroscopic characterization of digestates obtained from sludge mixed to increasing amounts of fruit and vegetable wastes

NASA Astrophysics Data System (ADS)

Provenzano, Maria Rosaria; Cavallo, Ornella; Malerba, Anna Daniela; Di Maria, Francesco; Ricci, Anna; Gigliotti, Giovanni

2015-04-01

Anaerobic digestion (AD) represents an efficient waste-treatment technology during which microorganisms break down biodegradable material in absence of oxygen yielding a biogas containing methane. The aim of this work was to investigate the transformations occurring in the organic matter during the co-digestion of waste mixed sludge (WMS) with an increasing amount of fruit and vegetable wastes (FVW) in a pilot scale apparatus reproducing a full-scale digester in an existing wastewater treatment plant. Samples comprised: sludge, FVW, sludge mixed with 10-20-30-40% FVW. Ingestates and digestates were analyzed by means of emission fluorescence spectroscopy and FTIR associated to Fourier self deconvolution (FSD) of spectra. With increasing the amount of FVW from 10% to 20% at which percentage biogas production reached the maximum value, FTIR spectra and FSD traces of digestates exhibited a decrease of intensity of peaks assigned to polysaccharides and aliphatics and an increase of peak assigned to aromatics as a result of the biodegradation of rapidly degradable materials and concentration of aromatic recalcitrant compounds. Digestates with 30 and 40% FVW exhibited a relative increase of intensity of peaks assigned to aliphatics likely as a result of the increasing amount of rapidly degradable materials and the consequent reduction of the hydraulic retention time. This may cause inhibition of methanogenesis and accumulation of volatile fatty acids. The highest emission fluorescence intensity was observed for the digestate with 20% FVW confirming the concentration of aromatic recalcitrant compounds in the substrate obtained at the highest biogas production.

40 CFR 61.354 - Monitoring of operations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... management unit in each waste treatment train, other than an enhanced biodegradation unit, measure the flow... specified in § 61.355(c)(3). (2) For each enhanced biodegradation unit that is the first exempt waste...

40 CFR 61.354 - Monitoring of operations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... management unit in each waste treatment train, other than an enhanced biodegradation unit, measure the flow... specified in § 61.355(c)(3). (2) For each enhanced biodegradation unit that is the first exempt waste...

40 CFR 61.354 - Monitoring of operations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... management unit in each waste treatment train, other than an enhanced biodegradation unit, measure the flow... specified in § 61.355(c)(3). (2) For each enhanced biodegradation unit that is the first exempt waste...

Slurry-phase biodegradation of weathered oily sludge waste.

PubMed

Machín-Ramírez, C; Okoh, A I; Morales, D; Mayolo-Deloisa, K; Quintero, R; Trejo-Hernández, M R

2008-01-01

We assessed the biodegradation of a typical oily sludge waste (PB401) in Mexico using several regimes of indigenous microbial consortium and relevant bioremediation strategies in slurry-phase system. Abiotic loss of total petroleum hydrocarbons (TPH) in the PB401 was insignificant, and degradation rates under the various treatment conditions ranged between 666.9 and 2168.7 mg kg(-1) day(-1) over a 15 days reaction period, while viable cell count peaked at between log(10)5.7 and log(10)7.4 cfu g(-1). Biostimulation with a commercial fertilizer resulted in 24% biodegradation of the TPH in the oily waste and a corresponding peak cell density of log(10)7.4 cfu g(-1). Addition of non-indigenous adapted consortium did not appear to enhance the removal of TPH from the oily waste. It would appear that the complexities of the components of the alkylaromatic fraction of the waste limited biodegradation rate even in a slurry system.

Biodigester Feasibility and Design for Space & Earth

NASA Technical Reports Server (NTRS)

Shutts, Stacy; Ewert, Mike; Bacon, Jack

2016-01-01

Anaerobic digestion converts organic waste into methane gas and fertilizer effluent. The ICA-developed prototype system is designed for planetary surface operation. It uses passive hydrostatic control for reliability, and is modular and redundant. The serpentine configuration accommodates tight geometric constraints similar to the ISS ECLSS rack architectures. Its shallow, low-tilt design enables (variable) lower-g convection than standard Earth (1 g) digesters. This technology will reuse and recycle materials including human waste, excess food, as well as packaging (if biodegradable bags are used).

Bio-treatment of oily sludge: the contribution of amendment material to the content of target contaminants, and the biodegradation dynamics.

PubMed

Kriipsalu, Mait; Marques, Marcia; Nammari, Diauddin R; Hogland, William

2007-09-30

The objective was to investigate the aerobic biodegradation of oily sludge generated by a flotation-flocculation unit (FFU) of an oil refinery wastewater treatment plant. Four 1m(3) pilot bioreactors with controlled air-flow were filled with FFU sludge mixed with one of the following amendments: sand (M1); matured oil compost (M2); kitchen waste compost (M3) and shredded waste wood (M4). The variables monitored were: pH, total petroleum hydrocarbons (TPHs), polycyclic aromatic hydrocarbons (PAHs), total carbon (C(tot)), total nitrogen (N(tot)) and total phosphorus (P(tot)). The reduction of TPH based on mass balance in M1, M2, M3 and M4 after 373 days of treatment was 62, 51, 74 and 49%; the reduction of PAHs was 97%, +13% (increase), 92 and 88%, respectively. The following mechanisms alone or in combination might explain the results: (i) most organics added with amendments biodegrade faster than most petroleum hydrocarbons, resulting in a relative increase in concentration of these recalcitrant contaminants; (ii) some amendments result in increased amounts of TPH and PAHs to be degraded in the mixture; (iii) sorption-desorption mechanisms involving hydrophobic compounds in the organic matrix reduce bioavailability, biodegradability and eventually extractability; (iv) mixture heterogeneity affecting sampling. Total contaminant mass reduction seems to be a better parameter than concentration to assess degradation efficiency in mixtures with high content of biodegradable amendments.

Biodegradation of plastics: current scenario and future prospects for environmental safety.

PubMed

Ahmed, Temoor; Shahid, Muhammad; Azeem, Farrukh; Rasul, Ijaz; Shah, Asad Ali; Noman, Muhammad; Hameed, Amir; Manzoor, Natasha; Manzoor, Irfan; Muhammad, Sher

2018-03-01

Plastic is a general term used for a wide range of high molecular weight organic polymers obtained mostly from the various hydrocarbon and petroleum derivatives. There is an ever-increasing trend towards the production and consumption of plastics due to their extensive industrial and domestic applications. However, a wide spectrum of these polymers is non-biodegradable with few exceptions. The extensive use of plastics, lack of waste management, and casual community behavior towards their proper disposal pose a significant threat to the environment. This has raised growing concerns among various stakeholders to devise policies and innovative strategies for plastic waste management, use of biodegradable polymers especially in packaging, and educating people for their proper disposal. Current polymer degradation strategies rely on chemical, thermal, photo, and biological procedures. In the presence of proper waste management strategies coupled with industrially controlled biodegradation facilities, the use of biodegradable plastics for some applications such as packaging or health industry is a promising and attractive option for economic, environmental, and health benefits. This review highlights the classification of plastics with special emphasis on biodegradable plastics and their rational use, the identified mechanisms of plastic biodegradation, the microorganisms involved in biodegradation, and the current insights into the research on biodegradable plastics. The review has also identified the research gaps in plastic biodegradation followed by future research directions.

Methane production by attached film

DOEpatents

Jewell, William J.

1981-01-01

A method for purifying wastewater of biodegradable organics by converting the organics to methane and carbon dioxide gases is disclosed, characterized by the use of an anaerobic attached film expanded bed reactor for the reaction process. Dilute organic waste material is initially seeded with a heterogeneous anaerobic bacteria population including a methane-producing bacteria. The seeded organic waste material is introduced into the bottom of the expanded bed reactor which includes a particulate support media coated with a polysaccharide film. A low-velocity upward flow of the organic waste material is established through the bed during which the attached bacterial film reacts with the organic material to produce methane and carbon dioxide gases, purified water, and a small amount of residual effluent material. The residual effluent material is filtered by the film as it flows upwardly through the reactor bed. In a preferred embodiment, partially treated effluent material is recycled from the top of the bed to the bottom of the bed for further treatment. The methane and carbon dioxide gases are then separated from the residual effluent material and purified water.

Degradation of plastic carrier bags in the marine environment.

PubMed

O'Brine, Tim; Thompson, Richard C

2010-12-01

There is considerable concern about the hazards that plastic debris presents to wildlife. Use of polymers that degrade more quickly than conventional plastics presents a possible solution to this problem. Here we investigate breakdown of two oxo-biodegradable plastics, compostable plastic and standard polyethylene in the marine environment. Tensile strength of all materials decreased during exposure, but at different rates. Compostable plastic disappeared from our test rig between 16 and 24 weeks whereas approximately 98% of the other plastics remained after 40 weeks. Some plastics require UV light to degrade. Transmittance of UV through oxo-biodegradable and standard polyethylene decreased as a consequence of fouling such that these materials received ∼ 90% less UV light after 40 weeks. Our data indicate that compostable plastics may degrade relatively quickly compared to oxo-biodegradable and conventional plastics. While degradable polymers offer waste management solutions, there are limitations to their effectiveness in reducing hazards associated with plastic debris. Copyright © 2010 Elsevier Ltd. All rights reserved.

Modelling of composting process of different organic waste at pilot scale: Biodegradability and odor emissions.

PubMed

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.

Reuse of polyethylene waste in road construction.

PubMed

Raju, S S S V Gopala; Murali, M; Rengaraju, V R

2007-01-01

The cost of construction of flexible pavements depends on thickness of the pavement layers. The thickness of pavement mainly depends on the strength of the subgrade. By suitable improvement to the strength of the subgrade, considerable saving in the scarce resources and economy can be achieved. Because of their lightweight, easy handling, non-breakable and corrosion free nature, polyethylene have surpassed all other materials in utility. But polyethylene waste has been a matter of concern to environmentalists as it is non-biodegradable. In this investigation, an attempt has been made to study the improvement of California Bearing Ratio (CBR) value of soils stabilized with waste polyethylene bags. This alternative material is mixed in different proportions to the gravel and clay to determine the improvement ofCBR value. Use of the waste polyethylene bags observed to have a significant impact on the strength and economy in pavement construction, when these are available locally in large quantities.

Natural biopolymer-based nanocomposite films for packaging applications.

PubMed

Rhim, Jong-Whan; Ng, Perry K W

2007-01-01

Concerns on environmental waste problems caused by non-biodegradable petrochemical-based plastic packaging materials as well as the consumer's demand for high quality food products has caused an increasing interest in developing biodegradable packaging materials using annually renewable natural biopolymers such as polysaccharides and proteins. Inherent shortcomings of natural polymer-based packaging materials such as low mechanical properties and low water resistance can be recovered by applying a nanocomposite technology. Polymer nanocomposites, especially natural biopolymer-layered silicate nanocomposites, exhibit markedly improved packaging properties due to their nanometer size dispersion. These improvements include increased modulus and strength, decreased gas permeability, and increased water resistance. Additionally, biologically active ingredients can be added to impart the desired functional properties to the resulting packaging materials. Consequently, natural biopolymer-based nanocomposite packaging materials with bio-functional properties have a huge potential for application in the active food packaging industry. In this review, recent advances in the preparation of natural biopolymer-based films and their nanocomposites, and their potential use in packaging applications are addressed.

Performance of mechanical biological treatment of residual municipal waste in Poland

NASA Astrophysics Data System (ADS)

den Boer, Emilia; Jędrczak, Andrzej

2017-11-01

The number and capacity of mechanical-biological treatment (MBT) plants in Europe increased significantly in the past two decades as a response to the legal obligation to limit the landfilling of biodegradable waste in landfills and to increase recycling and energy recovery from waste. The aim of these plants is to prepare residual municipal waste for recovery and disposal operations, including especially separation and stabilization of the easily biodegradable fraction (the biofraction). The final products of MBP technology are recyclables, stabilate, high calorific fraction which is used for the production of refuse derived fuel (RDF) and the remaining residual fraction. The shares of the output fractions, especially of the recyclables and RDF determine the overall efficiency of MBT technology in diverting waste from landfills. In this paper results of an assessment of one exemplary MBT plant are provided. The analysis was performed within a comparative study in which 20 selected MBT plants in Poland were subject to a detailed analysis, focusing, both at the design parameters as well as operational ones. The selected plant showed relatively higher overall materials recovery efficiency. With the view to circular economy targets, increased automation of the mechanical waste treatment will be required to support achieving high level diversion from landfills. The study reviled that stabilisation of biofraction should be improved by a better control of process conditions, especially moisture content.

Increased biogas production in a wastewater treatment plant by anaerobic co-digestion of fruit and vegetable waste and sewer sludge - a full scale study.

PubMed

Park, Nathan D; Thring, Ronald W; Garton, Randy P; Rutherford, Michael P; Helle, Steve S

2011-01-01

Anaerobic digestion is a well established technology for the reduction of organic matter and stabilization of wastewater. Biogas, a mixture of methane and carbon dioxide, is produced as a useful by-product of the process. Current solid waste management at the city of Prince George is focused on disposal of waste and not on energy recovery. Co-digestion of fresh fruit and vegetable waste with sewer sludge can improve biogas yield by increasing the load of biodegradable material. A six week full-scale project co-digesting almost 15,000 kg of supermarket waste was completed. Average daily biogas production was found to be significantly higher than in previous years. Digester operation remained stable over the course of the study as indicated by the consistently low volatile acids-to-alkalinity ratio. Undigested organic material was visible in centrifuged sludge suggesting that the waste should have been added to the primary digester to prevent short circuiting and to increase the hydraulic retention time of the freshly added waste.

Computational modelling of a thermoforming process for thermoplastic starch

NASA Astrophysics Data System (ADS)

Szegda, D.; Song, J.; Warby, M. K.; Whiteman, J. R.

2007-05-01

Plastic packaging waste currently forms a significant part of municipal solid waste and as such is causing increasing environmental concerns. Such packaging is largely non-biodegradable and is particularly difficult to recycle or to reuse due to its complex composition. Apart from limited recycling of some easily identifiable packaging wastes, such as bottles, most packaging waste ends up in landfill sites. In recent years, in an attempt to address this problem in the case of plastic packaging, the development of packaging materials from renewable plant resources has received increasing attention and a wide range of bioplastic materials based on starch are now available. Environmentally these bioplastic materials also reduce reliance on oil resources and have the advantage that they are biodegradable and can be composted upon disposal to reduce the environmental impact. Many food packaging containers are produced by thermoforming processes in which thin sheets are inflated under pressure into moulds to produce the required thin wall structures. Hitherto these thin sheets have almost exclusively been made of oil-based polymers and it is for these that computational models of thermoforming processes have been developed. Recently, in the context of bioplastics, commercial thermoplastic starch sheet materials have been developed. The behaviour of such materials is influenced both by temperature and, because of the inherent hydrophilic characteristics of the materials, by moisture content. Both of these aspects affect the behaviour of bioplastic sheets during the thermoforming process. This paper describes experimental work and work on the computational modelling of thermoforming processes for thermoplastic starch sheets in an attempt to address the combined effects of temperature and moisture content. After a discussion of the background of packaging and biomaterials, a mathematical model for the deformation of a membrane into a mould is presented, together with its finite element discretisation. This model depends on material parameters of the thermoplastic and details of tests undertaken to determine these and the results produced are given. Finally the computational model is applied for a thin sheet of commercially available thermoplastic starch material which is thermoformed into a specific mould. Numerical results of thickness and shape for this problem are given.

Organic compounds in re-circulated leachates of aerobic biological treated municipal solid waste.

PubMed

Franke, Matthias; Jandl, Gerald; Leinweber, Peter

2006-10-01

Biodegradation of organic matter is required to reduce the potential of municipal solid waste for producing gaseous emissions and leaching contaminants. Therefore, we studied leachates of an aerobic-treated waste from municipal solids and a sewage sludge mixture that were re-circulated to decrease the concentration of biodegradable organic matter in laboratory-scale reactors. After 12 months, the total organic C and biological and chemical oxygen demands were reduced, indicating the biodegradation of organic compounds in the leachates. Curie-point pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and pyrolysis-field ionization mass spectrometry (Py-FIMS) revealed that phenols, alkylaromatic compounds, N-containing compounds and carbohydrates were the predominate compounds in the leachates and solid waste. Leachate re-circulation led to a higher thermal stability of the residual organic matter as indicated by temperature-resolved Py-FIMS. Admixture of sewage sludge to solid waste was less effective in removing organic compounds from the leachates. It resulted in drastic higher and more bio-resistant loads of organic matter in the leachates and revealed increased proportions of alkylaromatic compounds. The biodegradation of organic matter in leachates, re-circulated through municipal solid waste, offers the potential for improved aerobic waste treatments and should be investigated on a larger scale.

Nitrogen conservation in simulated food waste aerobic composting process with different Mg and P salt mixtures.

PubMed

Li, Yu; Su, Bensheng; Liu, Jianlin; Du, Xianyuan; Huang, Guohe

2011-07-01

To assess the effects of three types of Mg and P salt mixtures (potassium phosphate [K3PO4]/magnesium sulfate [MgSO4], potassium dihydrogen phosphate [K2HPO4]/MgSO4, KH2PO4/MgSO4) on the conservation of N and the biodegradation of organic materials in an aerobic food waste composting process, batch experiments were undertaken in four reactors (each with an effective volume of 30 L). The synthetic food waste was composted of potatoes, rice, carrots, leaves, meat, soybeans, and seed soil, and the ratio of C and N was 17:1. Runs R1-R3 were conducted with the addition of K3PO4/ MgSO4, K2HPO4/MgSO4, and KH2PO4/MgSO4 mixtures, respectively; run R0 was a blank performed without the addition of Mg and P salts. After composting for 25 days, the degrees of degradation of the organic materials in runs R0-R3 were 53.87, 62.58, 59.14, and 49.13%, respectively. X-ray diffraction indicated that struvite crystals were formed in runs R1-R3 but not in run R0; the gaseous ammonia nitrogen (NH3-N) losses in runs R0-R3 were 21.2, 32.8, 12.6, and 3.5% of the initial total N, respectively. Of the tested Mg/P salt mixtures, the K2HPO4/ MgSO4 system provided the best combination of conservation of N and biodegradation of organic materials in this food waste composting process.

Vermicomposting of winery wastes: a laboratory study.

PubMed

Nogales, Rogelio; Cifuentes, Celia; Benítez, Emilio

2005-01-01

In Mediterranean countries, millions of tons of wastes from viticulture and winery industries are produced every year. This study describes the ability of the earthworm Eisenia andrei to compost different winery wastes (spent grape marc, vinasse biosolids, lees cakes, and vine shoots) into valuable agricultural products. The evolution of earthworm biomass and enzyme activities was tracked for 16 weeks of vermicomposting, on a laboratory scale. Increases in earthworm biomass for all winery wastes proved lower than in manure. Changes in hydrolytic enzymes and overall microbial activities during the vermicomposting process indicated the biodegradation of the winery wastes. Vermicomposting improved the agronomic value of the winery wastes by reducing the C:N ratio, conductivity and phytotoxicity, while increasing the humic materials, nutrient contents, and pH in all cases. Thus, winery wastes show potential as raw substrates in vermicomposting, although further research is needed to evaluate the feasibility of such wastes in large-scale vermicomposting systems.

Physical and mechanical properties of mortars containing PET and PC waste aggregates.

PubMed

Hannawi, Kinda; Kamali-Bernard, Siham; Prince, William

2010-11-01

Non-biodegradable plastic aggregates made of polycarbonate (PC) and polyethylene terephthalate (PET) waste are used as partial replacement of natural aggregates in mortar. Various volume fractions of sand 3%, 10%, 20% and 50% are replaced by the same volume of plastic. This paper investigates the physical and mechanical properties of the obtained composites. The main results of this study show the feasibility of the reuse of PC and PET waste aggregates materials as partial volume substitutes for natural aggregates in cementitious materials. Despite of some drawbacks like a decrease in compressive strength, the use of PC and PET waste aggregates presents various advantages. A reduction of the specific weight of the cementitious materials and a significant improvement of their post-peak flexural behaviour are observed. The calculated flexural toughness factors increase significantly with increasing volume fraction of PET and PC-aggregates. Thus, addition of PC and PET plastic aggregates in cementitious materials seems to give good energy absorbing materials which is very interesting for several civil engineering applications like structures subjected to dynamic or impact efforts. The present study has shown quite encouraging results and opened new way for the recycling of PC waste aggregate in cement and concrete composites. Copyright © 2010 Elsevier Ltd. All rights reserved.

How the origin of fresh household waste affects its ability to be biodegraded: an assessment using basic tools and its application to the city of Kara in Togo.

PubMed

Segbeaya, K N; Feuillade-Cathalifaud, G; Baba, G; Koledzi, E K; Pallier, V; Tchangbedji, G; Matejka, G

2012-12-01

Waste biodegradation has been largely investigated in the literature by using conventional tests like the BMP test and the respirometric test, whereas only few studies deal with the use of leaching tests in combination with biological activity measurements. Consequently, this study used an improved leaching test to evaluate the biodegradability of two deposits of fresh household waste from the city of Kara in Togo. The first deposit came from households in neighborhoods located in the outskirts of the city and the second consisted of fresh waste, mainly composed of business waste and household waste, collected in the urban center and aimed at being deposited in the landfill. A physicochemical characterization of the two deposits completed the leaching test. The biological activity was monitored by measuring O(2) consumption and CO(2) production. pH, DOC/OM, VFA/DOC ratios and the SUVA index was measured in the leaching juice to assess both the state of degradation of the waste in the deposits and the ability of the organic matter to be mobilized quickly and to be easily assimilated by microorganisms. The biodegradability of waste from the city of Kara correlated with their origin even though the physical characteristics of the two deposits studied differed greatly. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biodegradability standards for carrier bags and plastic films in aquatic environments: a critical review.

PubMed

Harrison, Jesse P; Boardman, Carl; O'Callaghan, Kenneth; Delort, Anne-Marie; Song, Jim

2018-05-01

Plastic litter is encountered in aquatic ecosystems across the globe, including polar environments and the deep sea. To mitigate the adverse societal and ecological impacts of this waste, there has been debate on whether 'biodegradable' materials should be granted exemptions from plastic bag bans and levies. However, great care must be exercised when attempting to define this term, due to the broad and complex range of physical and chemical conditions encountered within natural ecosystems. Here, we review existing international industry standards and regional test methods for evaluating the biodegradability of plastics within aquatic environments (wastewater, unmanaged freshwater and marine habitats). We argue that current standards and test methods are insufficient in their ability to realistically predict the biodegradability of carrier bags in these environments, due to several shortcomings in experimental procedures and a paucity of information in the scientific literature. Moreover, existing biodegradability standards and test methods for aquatic environments do not involve toxicity testing or account for the potentially adverse ecological impacts of carrier bags, plastic additives, polymer degradation products or small (microscopic) plastic particles that can arise via fragmentation. Successfully addressing these knowledge gaps is a key requirement for developing new biodegradability standard(s) for lightweight carrier bags.

Ethanolic extract of propolis for biodegradable films packaging enhanced with chitosan

NASA Astrophysics Data System (ADS)

Ismail, M. I.; Roslan, A.; Saari, N. S.; Hashim, K. H.; Kalamullah, M. R.

2017-09-01

The use of industrial organic waste which are chitosan and propolis as materials for the development of biodegradable and active packaging is economical and environmentally appealing. Processing of propolis-chitosan film can minimize waste, and produce low-cost added value biopolymer packaging films for targeted applications. This aims of this research is to develop and characterize a biodegradable films by incorporating chitosan with propolis extract to enhance the functional properties for potential use as active food packaging. The film's moisture content, solubility and antimicrobial activity increase due to increasing volume of propolis extract which are 0 ml, 1.2 ml and 2.4 ml of propolis extract. Propolis-chitosan film with 2.4 ml of propolis extract is more soluble in water compared to propolis-chitosan film with 0 ml of propolis extract and 1.2 ml of propolis extract. The higher the volume of the propolis extract used, the higher the solubility of film in the water. The moisture content also will increase when higher volume of propolis extract used. Characterization of moisture content, solubility and antimicrobial activities revealed the benefits of adding propolis extract into chitosan films and the potential of using the developed film as active food packaging.

Biopolymer-based thermoplastic mixture for producing solid biodegradable shaped bodies and its photo degradation stability

NASA Astrophysics Data System (ADS)

Sulong, Nurulsaidatulsyida; Rus, Anika Zafiah M.

2013-12-01

In recent years, biopolymers with controllable lifetimes have become increasingly important for many applications in the areas of agriculture, biomedical implants and drug release, forestry, wild life conservation and waste management. Natural oils are considered to be the most important class of renewable sources. They can be obtained from naturally occurring plants, such as sunflower, cotton, linseed and palm oil. In Malaysia, palm oil is an inexpensive and commodity material. Biopolymer produced from palm oil (Bio-VOP) is a naturally occurring biodegradable polymer and readily available from agriculture. For packaging use however, Bio-VOP is not thermoplastic and its granular form is unsuitable for most uses in the plastics industry, mainly due to processing difficulties during extrusion or injection moulding. Thus, research workers have developed several methods to blend Bio-VOP appropriately for industrial uses. In particular, injections moulding processes, graft copolymerisation, and preparation of blends with thermoplastic polymers have been studied to produce solid biodegradable shaped bodies. HDPE was chosen as commercial thermoplastic materials and was added with 10% Bio-VOP for the preparation of solid biodegradable shaped bodies named as HD-VOP. The UV light exposure of HD-VOP at 12 minutes upon gives the highest strength of this material that is 17.6 MPa. The morphological structure of HD-VOP shows dwi structure surface fracture which is brittle and ductile properties.

Synthesis of carbon nanotubes from waste polyethylene plastics

NASA Astrophysics Data System (ADS)

Zhuo, Chuanwei

Generation of non-biodegradable wastes, such as plastics, and resulting land as well as water pollution therefrom discarded plastics have been continuously increasing, while landfill space decreases and recycling markets dwindle. Exploration of novel uses of such materials becomes therefore imperative. Here I present an innovative and unique partial conversion of plastic waste to valuable carbon nanomaterials. It is an overall exothermic and scalable process based on feeding waste plastics to a multi-stage, pyrolysis/combustion-synthesis reactor. Plain stainless steel screens are used as substrates as well as low-cost catalyst for both carbon nanomaterials synthesis and pyrolyzates generation. Nano carbon yields of as high as 13.6% of the weight of the polymer precursor were recorded. This demonstration provides a sustainable solution to both plastic waste utilization, and carbon nanomaterials mass production.

Natural biopolimers in organic food packaging

NASA Astrophysics Data System (ADS)

Wieczynska, Justyna; Cavoski, Ivana; Chami, Ziad Al; Mondelli, Donato; Di Donato, Paola; Di Terlizzi, Biagio

2014-05-01

Concerns on environmental and waste problems caused by use of non-biodegradable and non-renewable based plastic packaging have caused an increase interest in developing biodegradable packaging using renewable natural biopolymers. Recently, different types of biopolymers like starch, cellulose, chitosan, casein, whey protein, collagen, egg white, soybean protein, corn zein, gelatin and wheat gluten have attracted considerable attention as potential food packaging materials. Recyclable or biodegradable packaging material in organic processing standards is preferable where possible but specific principles of packaging are not precisely defined and standards have to be assessed. There is evidence that consumers of organic products have specific expectations not only with respect to quality characteristics of processed food but also in social and environmental aspects of food production. Growing consumer sophistication is leading to a proliferation in food eco-label like carbon footprint. Biopolymers based packaging for organic products can help to create a green industry. Moreover, biopolymers can be appropriate materials for the development of an active surfaces designed to deliver incorporated natural antimicrobials into environment surrounding packaged food. Active packaging is an innovative mode of packaging in which the product and the environment interact to prolong shelf life or enhance safety or sensory properties, while maintaining the quality of the product. The work will discuss the various techniques that have been used for development of an active antimicrobial biodegradable packaging materials focusing on a recent findings in research studies. With the current focus on exploring a new generation of biopolymer-based food packaging materials with possible applications in organic food packaging. Keywords: organic food, active packaging, biopolymers , green technology

Study of Methanogenesis while Bioutilisation of Plant Residuals

NASA Astrophysics Data System (ADS)

Ilyin, V. K.; Korniushenkova, I. N.; Starkova, L. V.; Lauriniavichius, K. S.

respect principals of planet ecology, and compatibility with other habitability systems. For these purpose the waste management technologies, relevant to application of the biodegradation properties of bacteria are of great value. Biological treatment method is based upon the biodegradation of organic substances by various microorganisms. vegetable non-edible residual, using artificial inoculum; to study peculiarities of biogas, possibilities to optimize or to reduce the share of methane. fermentation. The biogas production achieved 46 l per 1 kg of substrate. The microbial studies of biodegradation process revealed following peculiarities: (i)gradual quantitative increasing of Lactobacillus sp. (from 103 to 105 colony forming units (CFU) per ml); (ii)activation of Clostridia sp. (from 102 to 104 CFU/ml); (iii) elimination of aerobic conventional pathogens (Enterobacteriaceae sp., Protea sp., staphylococci). methane content measures revealed traces 0.1-0.4%. granules, the amount of methane in biogas reached 80-90%. biodegradation of vegetable wastes. This inoculum consists of active sludge adapted to wastes mixed with excretes of insects which consume plant wastes. Using this inoculum the biodegradation process takes less time, then that using active sludge. Regulation of methane concentration from traces to 90% may be achieved by adding of methane reactor to the plant digester.

Doping, Ionic Conductivity and Photothermal Stability of Functionalized DNA for Solar Energy Conversion and Electrochromic Applications

DTIC Science & Technology

2011-06-01

and coworkers 1,2,3,4 . They are renewable and biodegradable materials, recovered from waste in food industry (fruits, animal and fish meat waste) and...charges leads to the change of its absorption spectrum, or in other words to a change of its color . However in most cases the electrolyte used is in...electrodes (cf. Fig. 25). CeO2- TiO2 BK7 BK7 SOLID ELECTROLYTE ITO WO3 ITO Fig. 25. Structure of the used electrochromic cell 21 Figure 26

Biodegradation of oil refinery wastes under OPA and CERCLA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gamblin, W.W.; Banipal, B.S.; Myers, J.M.

1995-12-31

Land treatment of oil refinery wastes has been used as a disposal method for decades. More recently, numerous laboratory studies have been performed attempting to quantify degradation rates of more toxic polycyclic aromatic hydrocarbon compounds (PAHs). This paper discusses the results of the fullscale aerobic biodegradation operations using land treatment at the Macmillan Ring-Free Oil refining facility. The tiered feasibility approach of evaluating biodegradation as a treatment method to achieve site-specific cleanup criteria, including pilot biodegradation operations, is discussed in an earlier paper. Analytical results of biodegradation indicate that degradation rates observed in the laboratory can be met and exceededmore » under field conditions and that site-specific cleanup criteria can be attained within a proposed project time. Also prevented are degradation rates and half-lives for PAHs for which cleanup criteria have been established. PAH degradation rates and half-life values are determined and compared with the laboratory degradation rates and half-life values which used similar oil refinery wastes by other in investigators (API 1987).« less

The second green revolution? Production of plant-based biodegradable plastics.

PubMed

Mooney, Brian P

2009-03-01

Biodegradable plastics are those that can be completely degraded in landfills, composters or sewage treatment plants by the action of naturally occurring micro-organisms. Truly biodegradable plastics leave no toxic, visible or distinguishable residues following degradation. Their biodegradability contrasts sharply with most petroleum-based plastics, which are essentially indestructible in a biological context. Because of the ubiquitous use of petroleum-based plastics, their persistence in the environment and their fossil-fuel derivation, alternatives to these traditional plastics are being explored. Issues surrounding waste management of traditional and biodegradable polymers are discussed in the context of reducing environmental pressures and carbon footprints. The main thrust of the present review addresses the development of plant-based biodegradable polymers. Plants naturally produce numerous polymers, including rubber, starch, cellulose and storage proteins, all of which have been exploited for biodegradable plastic production. Bacterial bioreactors fed with renewable resources from plants--so-called 'white biotechnology'--have also been successful in producing biodegradable polymers. In addition to these methods of exploiting plant materials for biodegradable polymer production, the present review also addresses the advances in synthesizing novel polymers within transgenic plants, especially those in the polyhydroxyalkanoate class. Although there is a stigma associated with transgenic plants, especially food crops, plant-based biodegradable polymers, produced as value-added co-products, or, from marginal land (non-food), crops such as switchgrass (Panicum virgatum L.), have the potential to become viable alternatives to petroleum-based plastics and an environmentally benign and carbon-neutral source of polymers.

Preparation and characterization of jackfruit seed starch/poly (vinyl alcohol) (PVA) blend film

NASA Astrophysics Data System (ADS)

Sarifuddin, N.; Shahrim, N. A.; Rani, N. N. S. A.; Zaki, H. H. M.; Azhar, A. Z. A.

2018-01-01

From the environmental point of view, biodegradable materials have been rapidly developed in the past years. PVA is one of the biodegradable synthetic polymers commonly used, but its degradation rate is slow. As an alternative to reduce plastic waste and accelerate the degradation process, PVA frequently blended with other natural polymers to improve its biodegradability. The natural polymer such as starch has high potential in enhancing PVA biodegradability by blending both components. The usage of starch extracted from agriculture wastes such as jackfruit seed is quite promising. In this study, jackfruit seed starch (JFSS)/poly (vinyl alcohol) (PVA) blend films were prepared using the solution casting method. The effect of starch content on the mechanical (tensile strength and elongation to break %) and physical properties of the tested films were investigated. The optimum tensile strength was obtained at 10.45 MPa when 4 wt. % of starch added to the blend. But, decreasing trend of tensile strength was found upon increasing the amount of starch beyond 4 wt. % in starch/PVA blend films. Nevertheless, elongation at break decreases with the increase in starch content. The mechanical properties of the blend films are supported by the Field Emission Scanning Electron Microscopy (FESEM), in which the native JFSS granules are wetted by PVA continuous phase with good dispersion and less agglomeration. The incorporation of JFSS in PVA has also resulted in the appearance of hydrogen bond peak, which evidenced by Fourier Transform Infrared (FTIR). Additionally, the biodegradation rate of JFSS/PVA was evaluated through soil burial test.

Keratinase production and biodegradation of polluted secondary chicken feather wastes by a newly isolated multi heavy metal tolerant bacterium-Alcaligenes sp. AQ05-001.

PubMed

Yusuf, Ibrahim; Ahmad, Siti Aqlima; Phang, Lai Yee; Syed, Mohd Arif; Shamaan, Nor Aripin; Abdul Khalil, Khalilah; Dahalan, Farrah Aini; Shukor, Mohd Yunus

2016-12-01

Biodegradation of agricultural wastes, generated annually from poultry farms and slaughterhouses, can solve the pollution problem and at the same time yield valuable degradation products. But these wastes also constitute environmental nuisance, especially in Malaysia where their illegal disposal on heavy metal contaminated soils poses a serious biodegradation issue as feather tends to accumulate heavy metals from the surrounding environment. Further, continuous use of feather wastes as cheap biosorbent material for the removal of heavy metals from effluents has contributed to the rising amount of polluted feathers, which has necessitated the search for heavy metal-tolerant feather degrading strains. Isolation, characterization and application of a novel heavy metal-tolerant feather-degrading bacterium, identified by 16S RNA sequencing as Alcaligenes sp. AQ05-001 in degradation of heavy metal polluted recalcitrant agricultural wastes, have been reported. Physico-cultural conditions influencing its activities were studied using one-factor-at-a-time and a statistical optimisation approach. Complete degradation of 5 g/L feather was achieved with pH 8, 2% inoculum at 27 °C and incubation period of 36 h. The medium optimisation after the response surface methodology (RSM) resulted in a 10-fold increase in keratinase production (88.4 U/mL) over the initial 8.85 U/mL when supplemented with 0.5% (w/v) sucrose, 0.15% (w/v) ammonium bicarbonate, 0.3% (w/v) skim milk, and 0.01% (w/v) urea. Under optimum conditions, the bacterium was able to degrade heavy metal polluted feathers completely and produced valuable keratinase and protein-rich hydrolysates. About 83% of the feathers polluted with a mixture of highly toxic metals were degraded with high keratinase activities. The heavy metal tolerance ability of this bacterium can be harnessed not only in keratinase production but also in the bioremediation of heavy metal-polluted feather wastes. Copyright © 2016. Published by Elsevier Ltd.

Evaluation of Biodegradability of Waste Before and After Aerobic Treatment

NASA Astrophysics Data System (ADS)

Suchowska-Kisielewicz, Monika; Jędrczak, Andrzej; Sadecka, Zofia

2014-12-01

An important advantage of use of an aerobic biostabilization of waste prior to its disposal is that it intensifies the decomposition of the organic fraction of waste into the form which is easily assimilable for methanogenic microorganisms involved in anaerobic decomposition of waste in the landfill. In this article it is presented the influence of aerobic pre-treatment of waste as well as leachate recirculation on susceptibility to biodegradation of waste in anaerobic laboratory reactors. The research has shown that in the reactor with aerobically treated waste stabilized with recilculation conversion of the organic carbon into the methane is about 45% higher than in the reactor with untreated waste stabilized without recirculation.

Progresses in Polystyrene Biodegradation and Prospects for Solutions to Plastic Waste Pollution

NASA Astrophysics Data System (ADS)

Yang, S. S.; Brandon, A. M.; Xing, D. F.; Yang, J.; Pang, J. W.; Criddle, C. S.; Ren, N. Q.; Wu, W. M.

2018-05-01

Petroleum-based plastic pollution has been a global environmental concern for decades. The obvious contrast between the remarkable durability of the plastics and their short service time leads to the increasing accumulation of plastic wastes in the environment. A cost-effective, sustainable strategy to solve the problem should focus on source control and clean up. Polystyrene (PS) wastes, a recalcitrant plastic polymer, are among the wide spread man-made plastic pollutants. Destruction of PS wastes can be achieved using various abiotic methods such as incineration but such methods release potential air pollution and generation of hazardous by-products. Biodegradation and bioremediation has been proposed for years. Since the 1970’s, the microbial biodegradation of plastics, including PS, has been evaluated with mixed and isolated cultures from different sources such as activated sludge, trash, soil, and manure. To date, PS biodegradation by these microbial cultures is still quite slow. Recently, the larvae of yellow mealworms (Tenebrio molitor Linnaeus) have demonstrated promising PS biodegradation performance. Mealworms have demonstrated the ability to chew and ingest PS foam as food and are capable of degrading and mineralizing PS into CO2 via microbe-dependent activities within the gut in less than the 12-15 hrs gut retention time. These research results have revealed a potential for microbial biodegradation and bioremediation of plastic pollutants.

An overview of the recent developments in polylactide (PLA) research.

PubMed

Madhavan Nampoothiri, K; Nair, Nimisha Rajendran; John, Rojan Pappy

2010-11-01

The concept of biodegradable plastics is of considerable interest with respect to solid waste accumulation. Greater efforts have been made in developing degradable biological materials without any environmental pollution to replace oil-based traditional plastics. Among numerous kinds of degradable polymers, polylactic acid sometimes called polylactide, an aliphatic polyester and biocompatible thermoplastic, is currently a most promising and popular material with the brightest development prospect and was considered as the 'green' eco friendly material. Biodegradable plastics like polyglycolic acid, polylactic acid, polycaprolactone, polyhydroxybutyrate, etc. are commercially available for controlled drug releases, implantable composites, bone fixation parts, packaging and paper coatings, sustained release systems for pesticides and fertilizers and compost bags etc. This review will provide information on current PLA market, brief account on recent developments in the synthesis of lactic acid (monomer of PLA) through biological route, PLA synthesis, unique material properties of PLA and modification of those by making copolymers and composites, PLA degradation and its wide spectrum applications.

Production and degradation of polyhydroxyalkanoates in waste environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, S.Y.; Choi, J.

1999-06-01

Polyhydroxyalkanoates (PHAs) are energy/carbon storage materials accumulated under unfavorable growth condition in the presence of excess carbon source. PHAs are attracting much attention as substitute for non-degradable petrochemically derived plastics because of their similar material properties to conventional plastics and complete biodegradability under natural environment upon disposal. In this paper, PHA production and degradation in waste environment as well as its role in biological phosphorus removal are reviewed. In biological phosphorus removal process, bacteria accumulating polyphosphate (poly P) uptake carbon substrates and accumulate these as PHA by utilizing energy from breaking down poly P under anaerobic conditions. In the followingmore » aerobic condition, accumulated PHA is utilized for energy generation and for the regeneration of poly P. PHA production from waste has been investigated in order to utilize abundant organic compounds in waste water. Since PHA content and PHA productivity that can be obtained are rather low, PHA production from waste product should be considered as a coupled process for reducing the amount of organic waste. PHAs can be rapidly degraded to completion in municipal anaerobic sludge by various microorganisms.« less

Characterization of Mechanical Properties of PP/HMSPP Blends with Natural and Synthetic Polymers Subjected to Gamma-Irradiation

NASA Astrophysics Data System (ADS)

Cardoso, E. C. L.; Scagliusi, S. R.; Lugão, A. B.

Hydrocarbon polymers, as PP, made from cheap petrochemical feedstock are important in many branches of industry. However, they have an undesirable influence on the environment and cause problems due to waste deposition and utilization. Polymeric materials composites account for an estimated from 20 to 30% of total volume of solid waste disposed. Thus, there is a tendency to substitute such polymers by those ones that undergo biodegradable processes. Polypropylene (PP) is a commodity, with high melting point, high chemical resistance, low density, with a balance between physical and mechanical properties and easy processing at low cost. Nevertheless, PP shows limitations for some special applications in automotive industry and civil construction. In order to minimize this deficiency, related to rheological behavior of polymer melt, especially referring to viscosity in processing temperature, a 50% mixture with HMSPP (High melt Strength Polypropylene) was used. PP/HMSPP was blended with 10, 15, 30 and 50% of natural (sugarcane bagasse) and synthetic polymers (PHB and PLA) aiming to partially biodegradable materials. The admixtures were subjected to gamma-irradiation at 50, 100, 150 and 200 kGy and then further assessed by mechanical tests in order to evaluate their degradability.

The biogeochemical fate of nickel during microbial ISA degradation; implications for nuclear waste disposal.

PubMed

Kuippers, Gina; Boothman, Christopher; Bagshaw, Heath; Ward, Michael; Beard, Rebecca; Bryan, Nicholas; Lloyd, Jonathan R

2018-06-08

Intermediate level radioactive waste (ILW) generally contains a heterogeneous range of organic and inorganic materials, of which some are encapsulated in cement. Of particular concern are cellulosic waste items, which will chemically degrade under the conditions predicted during waste disposal, forming significant quantities of isosaccharinic acid (ISA), a strongly chelating ligand. ISA therefore has the potential to increase the mobility of a wide range of radionuclides via complex formation, including Ni-63 and Ni-59. Although ISA is known to be metabolized by anaerobic microorganisms, the biodegradation of metal-ISA complexes remains unexplored. This study investigates the fate of a Ni-ISA complex in Fe(III)-reducing enrichment cultures at neutral pH, representative of a microbial community in the subsurface. After initial sorption of Ni onto Fe(III)oxyhydroxides, microbial ISA biodegradation resulted in >90% removal of the remaining Ni from solution when present at 0.1 mM, whereas higher concentrations of Ni proved toxic. The microbial consortium associated with ISA degradation was dominated by close relatives to Clostridia and Geobacter species. Nickel was preferentially immobilized with trace amounts of biogenic amorphous iron sulfides. This study highlights the potential for microbial activity to help remove chelating agents and radionuclides from the groundwater in the subsurface geosphere surrounding a geodisposal facility.

Biochemical methane potential, biodegradability, alkali treatment and influence of chemical composition on methane yield of yard wastes.

PubMed

Gunaseelan, Victor Nallathambi

2016-03-01

In this study, the biochemical CH4 potential, rate, biodegradability, NaOH treatment and the influence of chemical composition on CH4 yield of yard wastes generated from seven trees were examined. All the plant parts were sampled for their chemical composition and subjected to the biochemical CH4 potential assay. The component parts exhibited significant variation in biochemical CH4 potential, which was reflected in their ultimate CH4 yields that ranged from 109 to 382 ml g(-1) volatile solids added and their rate constants that ranged from 0.042 to 0.173 d(-1). The biodegradability of the yard wastes ranged from 0.26 to 0.86. Variation in the biochemical CH4 potential of the yard wastes could be attributed to variation in the chemical composition of the different fractions. In the Thespesia yellow withered leaf, Tamarindus fruit pericarp and Albizia pod husk, NaOH treatment enhanced the ultimate CH4 yields by 17%, 77% and 63%, respectively, and biodegradability by 15%, 77% and 61%, respectively, compared with the untreated samples. The effectiveness of NaOH treatment varied for different yard wastes, depending on the amounts of acid detergent fibre content. Gliricidia petals, Prosopis leaf, inflorescence and immature pod, Tamarindus seeds, Albizia seeds, Cassia seeds and Delonix seeds exhibited CH4 yields higher than 300 ml g(-1) volatile solids added. Multiple linear regression models for predicting the ultimate CH4 yield and biodegradability of yard wastes were designed from the results of this work. © The Author(s) 2016.

Assessment of anaerobic biodegradability of five different solid organic wastes

NASA Astrophysics Data System (ADS)

Kristanto, Gabriel Andari; Asaloei, Huinny

2017-03-01

The concept of waste to energy emerges as an alternative solution to increasing waste generation and energy crisis. In the waste to energy concept, waste will be used to produce renewable energy through thermochemical, biochemical, and physiochemical processes. In an anaerobic digester, organic matter brake-down due to anaerobic bacteria produces methane gas as energy source. The organic waste break-down is affected by various characteristics of waste components, such as organic matter content (C, N, O, H, P), solid contents (TS and VS), nutrients ratio (C/N), and pH. This research aims to analyze biodegradability and potential methane production (CH4) from organic waste largely available in Indonesia. Five solid wastes comprised of fecal sludge, cow rumen, goat farm waste, traditional market waste, and tofu dregs were analyzed which showed tofu dregs as waste with the highest rate of biodegradability compared to others since the tofu dregs do not contain any inhibitor which is lignin, have 2.7%VS, 14 C/N ratios and 97.3% organic matter. The highest cumulative methane production known as Biochemical Methane Potential was achieved by tofu dregs with volume of 77 ml during 30-day experiment which then followed by cow rumen, goat farm waste, and traditional market waste. Subsequently, methane productions were calculated through percentage of COD reduction, which showed the efficiency of 99.1% that indicates complete conversion of the high organic matter into methane.

Liquid scintillation sample analysis in microcentrifuge tubes.

PubMed

Elliott, J C

1993-01-01

Local regulations prohibiting drain disposal of "biodegradable" liquid scintillation cocktails prompted investigation of volume reduction for these materials. Microcentrifuge tubes were used with aqueous and filter media samples of 3H, 14C, 32P, and 125I. Backgrounds, counting efficiencies, figures of merit, and spectral distributions obtained for microcentrifuge tubes compared favorably to conventional vials. Differences in 32P spectra for solid support samples appeared related to filter material and sample volume. Decreases in sample costs and waste volume and disposal costs were approximately 50-75%.

Verification of vermural stabilization of ash from biomass and sewage sludge

NASA Astrophysics Data System (ADS)

Adamkova, L.; Kucerova, D.; Lyckova, B.; Kucerova, R.; Takac, D.

2017-10-01

The aim of this study was to find dependence on biofuels and sludge from sewage treatment plants in the vermicomposting process. In the framework of the research carried out at our workplace, a project aimed at finding an appropriate method for the reprocessing of problematic biodegradable waste and asphalt from combustion biomass was used as a raw material for the production of rectification substrate and sludge from sewage treatment plants that could be used as Secondary raw material.

Enhanced materials from nature: nanocellulose from citrus waste.

PubMed

Mariño, Mayra; Lopes da Silva, Lucimara; Durán, Nelson; Tasic, Ljubica

2015-04-03

Nanocellulose is a relatively inexpensive, highly versatile bio-based renewable material with advantageous properties, including biodegradability and nontoxicity. Numerous potential applications of nanocellulose, such as its use for the preparation of high-performance composites, have attracted much attention from industry. Owing to the low energy consumption and the addition of significant value, nanocellulose extraction from agricultural waste is one of the best alternatives for waste treatment. Different techniques for the isolation and purification of nanocellulose have been reported, and combining these techniques influences the morphology of the resultant fibers. Herein, some of the extraction routes for obtaining nanocellulose from citrus waste are addressed. The morphology of nanocellulose was determined by Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscopy (FESEM), while cellulose crystallinity indexes (CI) from lyophilized samples were determined using solid-state Nuclear Magnetic Resonance (NMR) and X-Ray Diffraction (XRD) measurements. The resultant nanofibers had 55% crystallinity, an average diameter of 10 nm and a length of 458 nm.

Production of L-lactic Acid from Biomass Wastes Using Scallop Crude Enzymes and Novel Lactic Acid Bacterium

NASA Astrophysics Data System (ADS)

Yanagisawa, Mitsunori; Nakamura, Kanami; Nakasaki, Kiyohiko

In the present study, biomass waste raw materials including paper mill sludge, bamboo, sea lettuce, and shochu residue (from a distiller) and crude enzymes derived from inedible and discarded scallop parts were used to produce L-lactic acid for the raw material of biodegradable plastic poly-lactic acid. The activities of cellulase and amylase in the crude enzymes were 22 and 170units/L, respectively, and L-lactic acid was produced from every of the above mentioned biomass wastes, by the method of liquid-state simultaneous saccharification and fermentation (SSF) . The L-lactic acid concentrations produced from sea lettuce and shochu residue, which contain high concentration of starch were 3.6 and 9.3g/L, respectively, and corresponded to greater than 25% of the conversion of glucans contained in these biomass wastes. Furthermore, using the solid state SSF method, concentrations as high as 13g/L of L-lactic acid were obtained from sea lettuce and 26g/L were obtained from shochu residue.

Polyhydroxyalkanoate (PHA) production from waste.

PubMed

Rhu, D H; Lee, W H; Kim, J Y; Choi, E

2003-01-01

PHA (polyhydroxyalkanoate) production was attempted with SBRs from food waste. Seed microbes were collected from a sewage treatment plant with a biological nutrient removal process, and acclimated with synthetic substrate prior to the application of the fermented food waste. Laboratory SBRs were used to produce PHA with limited oxygen and nutrients. The maximum content of 51% PHA was obtained with an anaerobic/aerobic cycle with P limitation, and the yield was estimated to be about 0.05 gPHA(produced)/gCOD(applied) or 25 kg PHA/dry ton of food waste, assuming more than 40% of the PHA contents were recoverable. PHB/PHA ratios were 0.74 to 0.77 due to the higher acetate concentrations. Economical analysis seemed to suggest the PHA produced from the food waste could be an alternative material to produce the biodegradable plastic to be used for the collection bags for solid waste.

Study of methanogenesis during bioutilization of plant residuals

NASA Astrophysics Data System (ADS)

Ilyin, V. K.; Korniushenkova, I. N.; Starkova, L. V.; Lauriniavichius, K. S.

2005-02-01

The waste management strategy for the future should meet the benefits of human safety, respect principles of planet ecology, and compatibility with other habitability systems. For these purposes waste management technologies relevant to application of the biodegradation properties of bacteria are of great value. Biological treatment method is based on the biodegradation of organic substances by various microorganisms. The objectives of our study were: to evaluate the effectiveness of microbial biodegradation of vegetable non-edible residual, using artificial inoculum, and to study the peculiarities of biogas, and possibilities of optimizing or reducing the share of methane. The diminution rate of organic gained 76% from initial mass within 9 days of fermentation. The biogas production achieved 46 l/kg of substrate. The microbial studies of biodegradation process revealed the following peculiarities: (i) gradual quantitative increase of Lactobacillus sp. (from 103 to 105 colony-forming units (CFU) per ml); (ii) activation of Clostridia sp. (from 102 to 10 4 CFU/ml); and (iii) elimination of aerobic conventional pathogens (Enterobacteriaceae, Protea sp., Staphylococci). Chromatography analysis revealed the constant presence of carbon dioxide (up to 90.9%). The methane content measures revealed traces 0.1-0.4%. However, when we optimized the methane production in "boiling layer" using methanogenic granules, the amount of methane in biogas reached 80-90%. Based on the results obtained the artificial inoculum was created which was capable of initiating biodegradation of vegetable wastes. This inoculum consisted of active sludge adapted to wastes mixed with excretea of insects which consume plant wastes. Using this inoculum the biodegradation process takes less time than that using active sludge. Regulation of methane concentration from traces to 90% may be achieved by adding methane reactor to the plant digester.

Cutin from agro-waste as a raw material for the production of bioplastics.

PubMed

Heredia-Guerrero, José A; Heredia, Antonio; Domínguez, Eva; Cingolani, Roberto; Bayer, Ilker S; Athanassiou, Athanassia; Benítez, José J

2017-11-09

Cutin is the main component of plant cuticles constituting the framework that supports the rest of the cuticle components. This biopolymer is composed of esterified bi- and trifunctional fatty acids. Despite its ubiquity in terrestrial plants, it has been underutilized as raw material due to its insolubility and lack of melting point. However, in recent years, a few technologies have been developed to obtain cutin monomers from several agro-wastes at an industrial scale. This review is focused on the description of cutin properties, biodegradability, chemical composition, processability, abundance, and the state of art of the fabrication of cutin-based materials in order to evaluate whether this biopolymer can be considered a source for the production of renewable materials. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Municipal solid waste generation in growing urban areas in Africa: current practices and relation to socioeconomic factors in Jimma, Ethiopia.

PubMed

Getahun, T; Mengistie, E; Haddis, A; Wasie, F; Alemayehu, E; Dadi, D; Van Gerven, T; Van der Bruggen, B

2012-10-01

As one of cities in the developing countries, a rapid population growth and industrial activities pose many environmental challenges for Jimma city, Ethiopia. One aspect of urban growth posing a threat on sustainable development is poor solid waste management, which results in environmental pollution. The purpose of this study is to evaluate the quantity, composition, sources of waste generated, their current disposal practices, and to recommend appropriate management technologies. The total waste generated daily in Jimma city was ca. 88,000 kg, and the average per capita generation rate was 0.55 ± 0.17 kg/capita/day. Eighty-seven percent of the waste was produced by households and 13% by institutions, and a negligible fraction (0.1%) was generated by street sweepings. During the rainy season, 40% more waste was generated than in the dry season because of the increased availability of agricultural food product. Further analysis showed that biodegradable organic waste constitutes 54% by weight with an average moisture content of 60% that falls within the required limits for composting. The nonbiodegradable components constitute 46% of which 30% of it was nonrecyclable material. Only 25% of the community uses municipal containers for disposal at the selected landfill site. Fifty-one percent of the households disposed their waste in individually chosen spots, whereas 22% burned their waste. Finally 2% of households use private waste collectors. The socioeconomic analysis showed that higher family income and educational status is associated more with private or municipal waste collection and less with the application of backyard or open dumping. These insights into generated waste and management practice in Jimma city allow making suggestions for improved collection, treatment, and disposal methods. A primary conclusion is that the biodegradable waste is a major fraction having suitable properties for recycling. As such an economic benefit can be obtained from this waste while avoiding the need for disposal.

Nanobarium Titanate As Supplement To Accelerate Plastic Waste Biodegradation By Indigenous Bacterial Consortia

NASA Astrophysics Data System (ADS)

Kapri, Anil; Zaidi, M. G. H.; Goel, Reeta

2009-06-01

Plastic waste biodegradation studies have seen several developmental phases from the discovery of potential microbial cultures, inclusion of photo-oxidizable additives into the polymer chain, to the creation of starch-embedded biodegradable plastics. The present study deals with the supplementation of nanobarium titanate (NBT) in the minimal broth in order to alter the growth-profiles of the Low-density polyethylene (LDPE) degrading consortia. The pro-bacterial influence of the nanoparticles could be seen by substantial changes such as shortening of the lag phase and elongation of the exponential as well as stationary growth phases, respectively, which eventually increase the biodegradation efficiency. In-vitro biodegradation studies revealed better dissolution of LDPE in the presence of NBT as compared to control. Significant shifting in λ-max values was observed in the treated samples through UV-Vis spectroscopy, while Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric-differential thermogravimetry-differential thermal analysis (TG-DTG-DTA) further confirmed the breakage and formation of bonds in the polymer backbone. Therefore, this study suggests the implementation of NBT as nutritional additive for plastic waste management through bacterial growth acceleration.

Biodegradability standards for carrier bags and plastic films in aquatic environments: a critical review

PubMed Central

Boardman, Carl; O'Callaghan, Kenneth; Delort, Anne-Marie; Song, Jim

2018-01-01

Plastic litter is encountered in aquatic ecosystems across the globe, including polar environments and the deep sea. To mitigate the adverse societal and ecological impacts of this waste, there has been debate on whether ‘biodegradable' materials should be granted exemptions from plastic bag bans and levies. However, great care must be exercised when attempting to define this term, due to the broad and complex range of physical and chemical conditions encountered within natural ecosystems. Here, we review existing international industry standards and regional test methods for evaluating the biodegradability of plastics within aquatic environments (wastewater, unmanaged freshwater and marine habitats). We argue that current standards and test methods are insufficient in their ability to realistically predict the biodegradability of carrier bags in these environments, due to several shortcomings in experimental procedures and a paucity of information in the scientific literature. Moreover, existing biodegradability standards and test methods for aquatic environments do not involve toxicity testing or account for the potentially adverse ecological impacts of carrier bags, plastic additives, polymer degradation products or small (microscopic) plastic particles that can arise via fragmentation. Successfully addressing these knowledge gaps is a key requirement for developing new biodegradability standard(s) for lightweight carrier bags. PMID:29892374

The influence of temperature on the formation of liquid fuel from Polypropylene plastic wastes

NASA Astrophysics Data System (ADS)

Martynis, M.; Mulyazmi; Praputri, E.; Witri, R.; Putri, N.

2018-03-01

The current trend of municipal waste management in urban areas is caused by rapid changes in social, economic, political and cultural life. As a non-biodegradable polymers that have become essential materials, plastic wastes have created a very serious environmental challenge because of the huge quantities and their disposal problems. Recycling of plastics is seen as one method for reducing environmental and resource depletion. The most attractive technique of plastics recycling is pyrolysis involving the degradation of the polymeric materials by heating in the absence of oxygen. This study investigated the characteristics of pyrolysis liquid fuel (PLF) produced from polypropylene plastic wastes with temperature variations. Pyrolisis was carried out on 200 grams of polypropylene waste plastics at the operating temperature of 200°C, 250°C, 300 °C and 350 °C for 45 minutes. The liquid products were found to have carbon chain length in the range of C8-C9, similar with gasoline. The maximum density, volume and calorific value of the oil obtained were 0.8 g/cm3, 61 ml and 1307 cal/gr, respectively.

Review of concrete biodeterioration in relation to nuclear waste.

PubMed

Turick, Charles E; Berry, Christopher J

2016-01-01

Storage of radioactive waste in concrete structures is a means of containing wastes and related radionuclides generated from nuclear operations in many countries. Previous efforts related to microbial impacts on concrete structures that are used to contain radioactive waste showed that microbial activity can play a significant role in the process of concrete degradation and ultimately structural deterioration. This literature review examines the research in this field and is focused on specific parameters that are applicable to modeling and prediction of the fate of concrete structures used to store or dispose of radioactive waste. Rates of concrete biodegradation vary with the environmental conditions, illustrating a need to understand the bioavailability of key compounds involved in microbial activity. Specific parameters require pH and osmotic pressure to be within a certain range to allow for microbial growth as well as the availability and abundance of energy sources such as components involved in sulfur, iron and nitrogen oxidation. Carbon flow and availability are also factors to consider in predicting concrete biodegradation. The microbial contribution to degradation of the concrete structures containing radioactive waste is a constant possibility. The rate and degree of concrete biodegradation is dependent on numerous physical, chemical and biological parameters. Parameters to focus on for modeling activities and possible options for mitigation that would minimize concrete biodegradation are discussed and include key conditions that drive microbial activity on concrete surfaces. Copyright © 2015. Published by Elsevier Ltd.

Biodegradation of free cyanide and subsequent utilisation of biodegradation by-products by Bacillus consortia: optimisation using response surface methodology.

PubMed

Mekuto, Lukhanyo; Ntwampe, Seteno Karabo Obed; Jackson, Vanessa Angela

2015-07-01

A mesophilic alkali-tolerant bacterial consortium belonging to the Bacillus genus was evaluated for its ability to biodegrade high free cyanide (CN(-)) concentration (up to 500 mg CN(-)/L), subsequent to the oxidation of the formed ammonium and nitrates in a continuous bioreactor system solely supplemented with whey waste. Furthermore, an optimisation study for successful cyanide biodegradation by this consortium was evaluated in batch bioreactors (BBs) using response surface methodology (RSM). The input variables, that is, pH, temperature and whey-waste concentration, were optimised using a numerical optimisation technique where the optimum conditions were found to be as follows: pH 9.88, temperature 33.60 °C and whey-waste concentration of 14.27 g/L, under which 206.53 mg CN(-)/L in 96 h can be biodegraded by the microbial species from an initial cyanide concentration of 500 mg CN(-)/L. Furthermore, using the optimised data, cyanide biodegradation in a continuous mode was evaluated in a dual-stage packed-bed bioreactor (PBB) connected in series to a pneumatic bioreactor system (PBS) used for simultaneous nitrification, including aerobic denitrification. The whey-supported Bacillus sp. culture was not inhibited by the free cyanide concentration of up to 500 mg CN(-)/L, with an overall degradation efficiency of ≥ 99 % with subsequent nitrification and aerobic denitrification of the formed ammonium and nitrates over a period of 80 days. This is the first study to report free cyanide biodegradation at concentrations of up to 500 mg CN(-)/L in a continuous system using whey waste as a microbial feedstock. The results showed that the process has the potential for the bioremediation of cyanide-containing wastewaters.

Bioremediation of Industrial Waste Through Enzyme Producing Marine Microorganisms.

PubMed

Sivaperumal, P; Kamala, K; Rajaram, R

Bioremediation process using microorganisms is a kind of nature-friendly and cost-effective clean green technology. Recently, biodegradation of industrial wastes using enzymes from marine microorganisms has been reported worldwide. The prospectus research activity in remediation area would contribute toward the development of advanced bioprocess technology. To minimize industrial wastes, marine enzymes could constitute a novel alternative in terms of waste treatment. Nowadays, the evidence on the mechanisms of bioremediation-related enzymes from marine microorganisms has been extensively studied. This review also will provide information about enzymes from various marine microorganisms and their complexity in the biodegradation of comprehensive range of industrial wastes. © 2017 Elsevier Inc. All rights reserved.

Composting Assessment for Organic Solid Waste at Fort Polk, Louisiana

DTIC Science & Technology

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

Energy performance of an integrated bio-and-thermal hybrid system for lignocellulosic biomass waste treatment.

PubMed

Kan, Xiang; Yao, Zhiyi; Zhang, Jingxin; Tong, Yen Wah; Yang, Wenming; Dai, Yanjun; Wang, Chi-Hwa

2017-03-01

Lignocellulosic biomass waste, a heterogeneous complex of biodegradables and non-biodegradables, accounts for large proportion of municipal solid waste. Due to limitation of single-stage treatment, a two-stage hybrid AD-gasification system was proposed in this work, in which AD acted as pre-treatment to convert biodegradables into biogas followed by gasification converting solid residue into syngas. Energy performance of single and two-stage systems treating 3 typical lignocellulosic wastes was studied using both experimental and numerical methods. In comparison with conventional single-stage gasification treatment, this hybrid system could significantly improve the quality of produced gas for all selected biomass wastes and show its potential in enhancing total gas energy production by a maximum value of 27% for brewer's spent grain treatment at an organic loading rate (OLR) of 3gVS/L/day. The maximum overall efficiency of the hybrid system for horticultural waste treatment was 75.2% at OLR of 11.3gVS/L/day, 5.5% higher than conventional single-stage system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gravimetric water distribution assessment from geoelectrical methods (ERT and EMI) in municipal solid waste landfill.

PubMed

Dumont, Gaël; Pilawski, Tamara; Dzaomuho-Lenieregue, Phidias; Hiligsmann, Serge; Delvigne, Frank; Thonart, Philippe; Robert, Tanguy; Nguyen, Frédéric; Hermans, Thomas

2016-09-01

The gravimetric water content of the waste material is a key parameter in waste biodegradation. Previous studies suggest a correlation between changes in water content and modification of electrical resistivity. This study, based on field work in Mont-Saint-Guibert landfill (Belgium), aimed, on one hand, at characterizing the relationship between gravimetric water content and electrical resistivity and on the other hand, at assessing geoelectrical methods as tools to characterize the gravimetric water distribution in a landfill. Using excavated waste samples obtained after drilling, we investigated the influences of the temperature, the liquid phase conductivity, the compaction and the water content on the electrical resistivity. Our results demonstrate that Archie's law and Campbell's law accurately describe these relationships in municipal solid waste (MSW). Next, we conducted a geophysical survey in situ using two techniques: borehole electromagnetics (EM) and electrical resistivity tomography (ERT). First, in order to validate the use of EM, EM values obtained in situ were compared to electrical resistivity of excavated waste samples from corresponding depths. The petrophysical laws were used to account for the change of environmental parameters (temperature and compaction). A rather good correlation was obtained between direct measurement on waste samples and borehole electromagnetic data. Second, ERT and EM were used to acquire a spatial distribution of the electrical resistivity. Then, using the petrophysical laws, this information was used to estimate the water content distribution. In summary, our results demonstrate that geoelectrical methods represent a pertinent approach to characterize spatial distribution of water content in municipal landfills when properly interpreted using ground truth data. These methods might therefore prove to be valuable tools in waste biodegradation optimization projects. Copyright © 2016 Elsevier Ltd. All rights reserved.

Numerical simulation of organic waste aerobic biodegradation: a new way to correlate respiration kinetics and organic matter fractionation.

PubMed

Denes, Jeremy; Tremier, Anne; Menasseri-Aubry, Safya; Walter, Christian; Gratteau, Laurette; Barrington, Suzelle

2015-02-01

Composting wastes permits the reuse of organic matter (OM) as agricultural amendments. The fate of OM during composting and the subsequent degradation of composts in soils largely depend on waste OM quality. The proposed study aimed at developing a model to predict the evolution in organic matter quality during the aerobic degradation of organic waste, based on the quantification of the various OM fractions contained in the wastes. The model was calibrated from data gathered during the monitoring of four organic wastes (two non-treated wastes and their digestates) exposed to respirometric tests. The model was successfully fitted for all four wastes and permitted to predict respiration kinetics, expressed as CO2 production rates, and the evolution of OM fractions. The calibrated model demonstrated that hydrolysis rates of OM fractions were similar for all four wastes whereas the parameters related to microbial activity (eg. growth and death rates) were specific to each substrate. These later parameters have been estimated by calibration on respirometric data, thus demonstrating that coupling analyses of OM fractions in initial wastes and respirometric tests permit the simulation of the biodegradation of various type of waste. The biodegradation model presented in this paper could thereafter be integrated in a composting model by implementing mass and heat balance equations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Methane production and hydrolysis kinetics in the anaerobic degradation of wastewater screenings.

PubMed

Cadavid-Rodríguez, L S; Horan, N

2013-01-01

Anaerobic biodegradability and hydrolysis rates of wastewater screenings were determined using the biochemical methane potential test at 37 °C. The extent and rate of screenings conversion to methane of this complex and particulate substrate were investigated and since two stages of hydrolysis were identified, corresponding to the different types of materials in screenings, a linear and non-linear model was used. No accumulation of intermediary products was observed and so it was possible to use the methane production rate and a linear model to estimate the hydrolysis rate in the first phase of hydrolysis. The measured values of 0.061-0.127 d(-1) are in the range reported for other comparable organic wastes. It was also observed that the inoculum-to-substrate ratio has a large impact on methane production rate of screenings. The difference in biodegradation rates from the materials in screenings and the overall hydrolysis could be represented by the modified Gompertz non-linear model which was able to describe the methane production rate of screenings with a high confidence. Screenings were found to have 52% biodegradability on average and this shows the potential for volatile solids destruction. A two-stage process with an improved hydrolysis rate is proposed to ensure that the full potential of the material is exploited.

Greenhouse Gas Emission Reduction Due to Improvement of Biodegradable Waste Management System

NASA Astrophysics Data System (ADS)

Bendere, R.; Teibe, I.; Arina, D.; Lapsa, J.

2014-12-01

To reduce emissions of greenhouse gas (GHG) from landfills, the European Union (EU) Landfill Directive 1999/31/EC requires that there be a progressive decrease in the municipal biodegradable waste disposal. The main problem of waste management (WM) in Latvia is its heavy dependence on the waste disposal at landfills. The poorly developed system for the sorted municipal waste collection and the promotion of landfilling as a major treatment option led to the disposal of 84% of the total collected municipal waste in 2012, with a high biodegradable fraction. In Latvia, the volume of emissions due to activities of the WM branch was 5.23% (632.6 CO2 eq.) of the total GHG emissions produced in the National economy in 2010 (12 097 Gg CO2 eq., except the land use, land-use change and forestry). Having revised the current situation in the management of biodegradable waste in Latvia, the authors propose improvements in this area. In the work, analysis of environmental impact was carried out using Waste Management Planning System (WAMPS) software in the WM modelling scenarios. The software computes the emissions, energy and turnover of waste streams for the processes within the WM system such as waste collection and transportation, composting, anaerobic digestion, and the final disposal (landfilling or incineration). The results of WAMPS modelling are presented in four categories associated with the environmental impact: acidification, global warming, eutrophication and photo-oxidant formation, each characterised by a particular emission. These categories cover an integrated WM system, starting with the point when products turn to waste which is then thrown into the bin for waste at its generation source, and ending with the point where the waste transforms either into useful material (recycled material, biogas or compost) or contributes to emissions into environment after the final disposal at a landfill or an incineration plant Rakstā veikts pašvaldības bioloģiski noārdāmo atkritumu apsaimniekošanas statistikas datu novērtējums atbilstoši likumdošanas prasībām. Izmantojot matemātisko modelēšanas programmu WAMPS, analizēti trīs dažādi bioloģisko noārdāmo atkritumu apsaimniekošanas scenāriji, kuriem veikts vides ietekmes novērtējums, kas izteikts klimata pārmaiņu potenciālā - tonnas CO2 ekv. Darbā secināts, ka lielākais siltumnīcefektu (SEG) avots atkritumu apsaimniekošanas ir atkritumu poligoni (Bāzes scenārijs), ko galvenokārt ietekmē CH4 rašanās, organiskajiem atkritumiem sadaloties anaerobos apstākļos. Būtisku pozitīvo efektu SEG emisiju samazināšanā dod atkritumu pārstrāde otrreizējās izejvielās un sadedzināšana cementa ražotnē, kas ļauj samazināt dabīgo izejmateriālu un fosilo enerģijas resursu patēriņu. Attīstot pārtikas atkritumu pārstrādi biogāzē, lietderīgi veidot alternatīvās vai izmantot esošās sistēmas, kas nodrošina iegūtās enerģijas un digestāta patēriņu, t.i lauksaimniecība, transports vai komunālie pakalpojumi. Lai no zaļajiem dārza atkritumiem iegūtu augstvērtīgu kompostu, valstī jārada tam nepieciešami likumdošanas un ekonomiskie instrumenti, kas veicina komposta tirgus attīstību.

High barrier multilayer packaging by the coextrusion method: The effect of nanocomposites and biodegradable polymers on flexible film properties

NASA Astrophysics Data System (ADS)

Thellen, Christopher T.

The objective of this research was to investigate the use of nanocomposite and multilayer co-extrusion technologies for the development of high gas barrier packaging that is more environmentally friendly than many current packaging system. Co-extruded bio-based and biodegradable polymers that could be composted in a municipal landfill were one direction that this research was aimed. Down-gauging of high performance barrier films using nanocomposite technology and co-extrusion was also investigated in order to reduce the amount of solid waste being generated by the packaging. Although the research is focused on military ration packaging, the technologies could easily be introduced into the commercial flexible packaging market. Multilayer packaging consisting of poly(m-xylylene adipamide) nanocomposite layers along with adhesive and tie layers was co-extruded using both laboratory and pilot-scale film extrusion equipment. Co-extrusion of biodegradable polyhydroxyalkanoates (PHA) along with polyvinyl alcohol (PVOH) and tie layers was also accomplished using similar co-extrusion technology. All multilayer films were characterized for gas barrier, mechanical, and thermal properties. The biodegradability of the PVOH and PHA materials in a marine environment was also investigated. The research has shown that co-extrusion of these materials is possible at a research and pilot level. The use of nanocomposite poly(m-xylylene adipamide) was effective in down-gauging the un-filled barrier film to thinner structures. Bio-based PHA/PVOH films required the use of a malefic anhydride grafted PHA tie layer to improve layer to layer adhesion in the structure to avoid delamination. The PHA polymer demonstrated a high rate of biodegradability/mineralization in the marine environment while the rate of biodegradation of the PVOH polymer was slower.

Coupling hydrothermal liquefaction and anaerobic digestion for energy valorization from model biomass feedstocks.

PubMed

Posmanik, Roy; Labatut, Rodrigo A; Kim, Andrew H; Usack, Joseph G; Tester, Jefferson W; Angenent, Largus T

2017-06-01

Hydrothermal liquefaction converts food waste into oil and a carbon-rich hydrothermal aqueous phase. The hydrothermal aqueous phase may be converted to biomethane via anaerobic digestion. Here, the feasibility of coupling hydrothermal liquefaction and anaerobic digestion for the conversion of food waste into energy products was examined. A mixture of polysaccharides, proteins, and lipids, representing food waste, underwent hydrothermal processing at temperatures ranging from 200 to 350°C. The anaerobic biodegradability of the hydrothermal aqueous phase was examined through conducting biochemical methane potential assays. The results demonstrate that the anaerobic biodegradability of the hydrothermal aqueous phase was lower when the temperature of hydrothermal processing increased. The chemical composition of the hydrothermal aqueous phase affected the anaerobic biodegradability. However, no inhibition of biodegradation was observed for most samples. Combining hydrothermal and anaerobic digestion may, therefore, yield a higher energetic return by converting the feedstock into oil and biomethane. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Investigation of the process of personal hygiene items biodegradation by cellulose-fermenting microorganisms].

PubMed

Il'in, V K; Starkov, L V; Kostrov, S V; Belikodvorskaia, G A; Chuvil'skaia, N A; Mukhamedieva, L N; Mikos, K N

2004-01-01

Cellulose-containing wastes are one of the heaviest and biggest ingredients of solid domestic wastes piling up during spaceflight. For the most part these are disposable personal hygiene items used in large quantities in the absence of shower. These wastes contain human body products which are very dangerous from the sanitary-epidemiological standpoint. The purpose was to explore potentiality of microbial biodegradation of cellulose-containing hygiene items anaerobically with dry mass transformation into liquid and biogas. Among specific objectives were test cultivation of active strains of reference cultures of cellulose-fermenting anaerobic thermophilic bacteria on hygiene items as the only source of carbon, evaluation of ways and need of pretreatment of gauze pads to stimulate biodegradation, and chemical analysis of resulting biogas. From the investigation it was concluded that gauze pads are susceptible to biodegradation by anaerobic bacteria producing a low toxicity gas fraction. Therefore, the proposed technology can be considered as a candidate for integration into the spacecrew life support system.

76 FR 34147 - Land Disposal Restrictions: Revision of the Treatment Standards for Carbamate Wastes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-13

... carbamate wastewaters to be treated using combustion, chemical oxidation, biodegradation or carbon..., biodegradation or carbon adsorption for wastewaters. The numeric treatment standard concentration limits were... in the table 40 CFR 268.42) for nonwastewaters; and, combustion, chemical oxidation, biodegradation...

The use of fly larvae for organic waste treatment.

PubMed

Čičková, Helena; Newton, G Larry; Lacy, R Curt; Kozánek, Milan

2015-01-01

The idea of using fly larvae for processing of organic waste was proposed almost 100 years ago. Since then, numerous laboratory studies have shown that several fly species are well suited for biodegradation of organic waste, with the house fly (Musca domestica L.) and the black soldier fly (Hermetia illucens L.) being the most extensively studied insects for this purpose. House fly larvae develop well in manure of animals fed a mixed diet, while black soldier fly larvae accept a greater variety of decaying organic matter. Blow fly and flesh fly maggots are better suited for biodegradation of meat processing waste. The larvae of these insects have been successfully used to reduce mass of animal manure, fecal sludge, municipal waste, food scrapes, restaurant and market waste, as well as plant residues left after oil extraction. Higher yields of larvae are produced on nutrient-rich wastes (meat processing waste, food waste) than on manure or plant residues. Larvae may be used as animal feed or for production of secondary products (biodiesel, biologically active substances). Waste residue becomes valuable fertilizer. During biodegradation the temperature of the substrate rises, pH changes from neutral to alkaline, ammonia release increases, and moisture decreases. Microbial load of some pathogens can be substantially reduced. Both larvae and digested residue may require further treatment to eliminate pathogens. Facilities utilizing natural fly populations, as well as pilot and full-scale plants with laboratory-reared fly populations have been shown to be effective and economically feasible. The major obstacles associated with the production of fly larvae from organic waste on an industrial scale seem to be technological aspects of scaling-up the production capacity, insufficient knowledge of fly biology necessary to produce large amounts of eggs, and current legislation. Technological innovations could greatly improve performance of the biodegradation facilities and decrease production costs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of oxidized leachate on degradation of lignin by sulfate-reducing bacteria.

PubMed

Kim, Jong-Ho; Kim, Moonil; Bae, Wooken

2009-08-01

Municipal solid waste materials (MSWs) in landfills need a long period of stabilization because lignin compounds in MSWs and leachate are not readily biodegraded, but inhibit methanogenic metabolism. Recirculation of leachate into the landfill offers the potential advantage of increasing the rate of decomposition of organic matter. However, the degradation of lignin by leachate recirculation alone is quite difficult. Several recent studies have demonstrated that sulfate-reducing bacteria (SRB) were able to degrade lignin compounds. In this study, batch tests were conducted to investigate the impacts of SRB enrichment on lignin decomposition rates as well as the decomposition of other biodegradable organics. Further, the effects of nitrite and nitrate on lignin degradation rates were also studied. A 16S rRNA assay showed that the SRB used herein, which were obtained by enriching solid waste collected from a closed MSW landfill, were Thaurea sp. and Desulfovibrio sp. Lignin was found to be biodegraded by the SRB and the rate of lignin removal per unit of waste volatile suspended solid was 2.9 mg lignin g(-1) VSS day(- 1). It was found that the initial degradation rate increased under higher initial lignin concentrations. However, the degradation rate during days 6-19 became slower than that during the initial 9 days because lignin consisted of complexly bonded aromatic compounds that were not readily biodegradable. Adding other organics such as lactate seemed to improve the rate and amount of lignin degradation, probably due to the increase in SRB associated with consumption of the additional organics. The lignin removal percentage decreased with increases in oxidized nitrogen (nitrite or nitrate) concentrations, indicating that oxidized nitrogen could inhibit SRB activity. Conclusively, the study verified the existence of SRB in the landfill and showed that the SRB could be activated for the degradation of lignin by the recirculation of the leachate, which is consistent with other studies showing that leachate recirculation could shorten the stabilization period of the landfill.

Laboratory Test Methods to Determine the Degradation of Plastics in Marine Environmental Conditions

PubMed Central

Tosin, Maurizio; Weber, Miriam; Siotto, Michela; Lott, Christian; Degli Innocenti, Francesco

2012-01-01

In this technology report, three test methods were developed to characterize the degradation of plastic in marine environment. The aim was to outline a test methodology to measure the physical and biological degradation in different habitats where plastic waste can deposit when littered in the sea. Previously, research has focused mainly on the conditions encountered by plastic items when floating in the sea water (pelagic domain). However, this is just one of the possible habitats that plastic waste can be exposed to. Waves and tides tend to wash up plastic waste on the shoreline, which is also a relevant habitat to be studied. Therefore, the degradation of plastic items buried under sand kept wet with sea water has been followed by verifying the disintegration (visual disappearing) as a simulation of the tidal zone. Most biodegradable plastics have higher densities than water and also as a consequence of fouling, they tend to sink and lay on the sea floor. Therefore, the fate of plastic items lying on the sediment has been followed by monitoring the oxygen consumption (biodegradation). Also the effect of a prolonged exposure to the sea water, to simulate the pelagic domain, has been tested by measuring the decay of mechanical properties. The test material (Mater-Bi) was shown to degrade (total disintegration achieved in less than 9 months) when buried in wet sand (simulation test of the tidal zone), to lose mechanical properties but still maintain integrity (tensile strength at break = −66% in 2 years) when exposed to sea water in an aquarium (simulation of pelagic domain), and substantially biodegrade (69% in 236 days; biodegradation relative to paper: 88%) when located at the sediment/sea water interface (simulation of benthic domain). This study is not conclusive as the methodological approach must be completed by also determining degradation occurring in the supralittoral zone, on the deep sea floor, and in the anoxic sediment. PMID:22737147

Laboratory test methods to determine the degradation of plastics in marine environmental conditions.

PubMed

Tosin, Maurizio; Weber, Miriam; Siotto, Michela; Lott, Christian; Degli Innocenti, Francesco

2012-01-01

In this technology report, three test methods were developed to characterize the degradation of plastic in marine environment. The aim was to outline a test methodology to measure the physical and biological degradation in different habitats where plastic waste can deposit when littered in the sea. Previously, research has focused mainly on the conditions encountered by plastic items when floating in the sea water (pelagic domain). However, this is just one of the possible habitats that plastic waste can be exposed to. Waves and tides tend to wash up plastic waste on the shoreline, which is also a relevant habitat to be studied. Therefore, the degradation of plastic items buried under sand kept wet with sea water has been followed by verifying the disintegration (visual disappearing) as a simulation of the tidal zone. Most biodegradable plastics have higher densities than water and also as a consequence of fouling, they tend to sink and lay on the sea floor. Therefore, the fate of plastic items lying on the sediment has been followed by monitoring the oxygen consumption (biodegradation). Also the effect of a prolonged exposure to the sea water, to simulate the pelagic domain, has been tested by measuring the decay of mechanical properties. The test material (Mater-Bi) was shown to degrade (total disintegration achieved in less than 9 months) when buried in wet sand (simulation test of the tidal zone), to lose mechanical properties but still maintain integrity (tensile strength at break = -66% in 2 years) when exposed to sea water in an aquarium (simulation of pelagic domain), and substantially biodegrade (69% in 236 days; biodegradation relative to paper: 88%) when located at the sediment/sea water interface (simulation of benthic domain). This study is not conclusive as the methodological approach must be completed by also determining degradation occurring in the supralittoral zone, on the deep sea floor, and in the anoxic sediment.

Cellulose nanocrystals in nanocomposite approach: Green and high-performance materials for industrial, biomedical and agricultural applications

NASA Astrophysics Data System (ADS)

Fortunati, E.; Torre, L.

2016-05-01

The need to both avoid wastes and find new renewable resources has led to a new and promising research based on the possibility to revalorize the biomass producing sustainable chemicals and/or materials which may play a major role in replacing systems traditionally obtained from non-renewable sources. Most of the low-value biomass is termed lignocellulosic, referring to its main constituent biopolymers: cellulose, hemicelluloses and lignin. In this context, nanocellulose, and in particular cellulose nanocrystals (CNC), have gain considerable attention as nanoreinforcement for polymer matrices, mainly biodegradable. Derived from the most abundant polymeric resource in nature and with inherent biodegradability, nanocellulose is an interesting nanofiller for the development of nanocomposites for industrial, biomedical and agricultural applications. Due to the high amount of hydroxyl groups on their surface, cellulose nanocrystals are easy to functionalize. Well dispersed CNC are able, in fact, to enhance several properties of polymers, i.e.: thermal, mechanical, barrier, surface wettability, controlled of active compound and/or drug release. The main objective here is to give a general overview of CNC applications, summarizing our recent developments of bio-based nanocomposite formulations reinforced with cellulose nanocrystals extracted from different natural sources and/or wastes for food packaging, medical and agricultural sectors.

Engineering and functional properties of biodegradable pellets developed from various agro-industrial wastes using extrusion technology.

PubMed

Jan, Kulsum; Riar, C S; Saxena, D C

2015-12-01

Different agro-industrial wastes were mixed with different plasticizers and extruded to form the pellets to be used further for development of biodegradable molded pots. Bulk density and macro-porosity are the important engineering properties used to determine the functional characteristics of the biodegradable pellets viz., expansion volume, water solubility, product colour, flowability and compactness. Significant differences in the functional properties of pellets with varying bulk densities (loose and tapped) and macro-porosities (loose, tapped) were observed. The observed mean bulk density of biodegradable pellets made from different formulations ranged between 0.213 and 0.560 g/ml for loose fill conditions and 0.248 to 0.604 g/ml for tapped fill conditions. Biodegradable pellets bear a good compaction for both loose and tapped fill methods. The mean macro-porosity of biodegradable pellets ranged between 1.19 and 54.48 % for loose fill condition and 0.29 to 53.35 % for tapped fill condition. Hausner ratio (HR) for biodegradable pellets varied from 1.026 to 1.328, indicating a good flowability of biodegradable pellets. Pearson's correlation between engineering properties and functional properties of biodegradable pellets revealed that from engineering properties functional properties can be predicted.

Determination of biodegradability kinetics of RCRA compounds using respirometry for structure-activity relationships

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tabak, H.H.; Desai, S.; Govind, R.

1990-01-01

Electrolytic respirometry is attaining prominence in biodegradation studies and is becoming one of the more suitable experimental methods for measuring the biodegradability and the kinetics of biodegradation of toxic organic compounds by the sewage, sludge, and soil microbiota and for determining substrate inhibitory effects to microorganisms in wastewater treatment systems. The purpose of the study was to obtain information on biological treatability of the benzene, phenol, phthalate, ketone organics and of the Superfund CERCLA organics bearing wastes in wastewater treatment systems which will support the development of an EPA technical guidance document on the discharge of the above organics tomore » POTWs. The paper discusses the experimental design and procedural steps for the respirometric biodegradation and toxicity testing approach for individual organics or specific industrial wastes at different concentration levels in a mineral salts medium. A developed multi-level protocol is presented for determination of the biodegradability, microbial acclimation to toxic substrates and first order kinetic parameters of biodegradation for estimation of the Monod kinetic parameter of toxic organic compounds, in order to correlate the extent and rate of biodegradation with a predictive model based on chemical properties and molecular structure of these compounds. Respirometric biodegradation/inhibition and biokinetic data are provided for representative RCRA alkyl benzene and ketone organics.« less

Fate and transport of phenol in a packed bed reactor containing simulated solid waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saquing, Jovita M., E-mail: jmsaquing@gmail.com; Knappe, Detlef R.U., E-mail: knappe@ncsu.edu; Barlaz, Morton A., E-mail: barlaz@ncsu.edu

Highlights: Black-Right-Pointing-Pointer Anaerobic column experiments were conducted at 37 Degree-Sign C using a simulated waste mixture. Black-Right-Pointing-Pointer Sorption and biodegradation model parameters were determined from batch tests. Black-Right-Pointing-Pointer HYDRUS simulated well the fate and transport of phenol in a fully saturated waste column. Black-Right-Pointing-Pointer The batch biodegradation rate and the rate obtained by inverse modeling differed by a factor of {approx}2. Black-Right-Pointing-Pointer Tracer tests showed the importance of hydrodynamic parameters to improve model estimates. - Abstract: An assessment of the risk to human health and the environment associated with the presence of organic contaminants (OCs) in landfills necessitates reliable predictivemore » models. The overall objectives of this study were to (1) conduct column experiments to measure the fate and transport of an OC in a simulated solid waste mixture, (2) compare the results of column experiments to model predictions using HYDRUS-1D (version 4.13), a contaminant fate and transport model that can be parameterized to simulate the laboratory experimental system, and (3) determine model input parameters from independently conducted batch experiments. Experiments were conducted in which sorption only and sorption plus biodegradation influenced OC transport. HYDRUS-1D can reasonably simulate the fate and transport of phenol in an anaerobic and fully saturated waste column in which biodegradation and sorption are the prevailing fate processes. The agreement between model predictions and column data was imperfect (i.e., within a factor of two) for the sorption plus biodegradation test and the error almost certainly lies in the difficulty of measuring a biodegradation rate that is applicable to the column conditions. Nevertheless, a biodegradation rate estimate that is within a factor of two or even five may be adequate in the context of a landfill, given the extended retention time and the fact that leachate release will be controlled by the infiltration rate which can be minimized by engineering controls.« less

Reutilization of discarded biomass for preparing functional polymer materials.

PubMed

Wang, Jianfeng; Qian, Wenzhen; He, Yufeng; Xiong, Yubing; Song, Pengfei; Wang, Rong-Min

2017-07-01

Biomass is abundant and recyclable on the earth, which has been assigned numerous roles to human beings. However, over the past decades, accompanying with the rapid expansion of man-made materials, such as alloy, plastic, synthetic rubber and fiber, a great number of natural materials had been neglected and abandoned, such as straw, which cause a waste of resource and environmental pollution. In this review, based on introducing sources of discarded biomass, the main composition and polymer chains in discarded biomass materials, the traditional treatment and novel approach for reutilization of discarded biomass were summarized. The discarded biomass mainly come from plant wastes generated in the process of agriculture and forestry production and manufacturing processes, animal wastes generated in the process of animal husbandry and fishery production as well as the residual wastes produced in the process of food processing and rural living garbage. Compared with the traditional treatment including burning, landfill, feeding and fertilizer, the novel approach for reutilization of discarded biomass principally allotted to energy, ecology and polymer materials. The prepared functional materials covered in composite materials, biopolymer based adsorbent and flocculant, carrier materials, energy materials, smart polymer materials for medical and other intelligent polymer materials, which can effectively serve the environmental management and human life, such as wastewater treatment, catalyst, new energy, tissue engineering, drug controlled release, and coating. To sum up, the renewable and biodegradable discarded biomass resources play a vital role in the sustainable development of human society, as well as will be put more emphases in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 264.1082 - Standards: General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 264.1083(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 61.348 - Standards: Treatment processes.

Code of Federal Regulations, 2013 CFR

2013-07-01

... enhanced biodegradation unit shall not be included in the calculation of the total annual benzene quantity, if the enhanced biodegradation unit is the first exempt unit in which the waste is managed or treated. A unit shall be considered enhanced biodegradation if it is a suspended-growth process that...

40 CFR 265.1083 - Standards: General.

Code of Federal Regulations, 2013 CFR

2013-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 265.1084(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 61.348 - Standards: Treatment processes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... enhanced biodegradation unit shall not be included in the calculation of the total annual benzene quantity, if the enhanced biodegradation unit is the first exempt unit in which the waste is managed or treated. A unit shall be considered enhanced biodegradation if it is a suspended-growth process that...

40 CFR 61.348 - Standards: Treatment processes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... enhanced biodegradation unit shall not be included in the calculation of the total annual benzene quantity, if the enhanced biodegradation unit is the first exempt unit in which the waste is managed or treated. A unit shall be considered enhanced biodegradation if it is a suspended-growth process that...

40 CFR 264.1082 - Standards: General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 264.1083(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 61.348 - Standards: Treatment processes.

Code of Federal Regulations, 2014 CFR

2014-07-01

... enhanced biodegradation unit shall not be included in the calculation of the total annual benzene quantity, if the enhanced biodegradation unit is the first exempt unit in which the waste is managed or treated. A unit shall be considered enhanced biodegradation if it is a suspended-growth process that...

40 CFR 265.1083 - Standards: General.

Code of Federal Regulations, 2012 CFR

2012-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 265.1084(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 264.1082 - Standards: General.

Code of Federal Regulations, 2014 CFR

2014-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 264.1083(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 265.1083 - Standards: General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 265.1084(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 264.1082 - Standards: General.

Code of Federal Regulations, 2012 CFR

2012-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 264.1083(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 98.464 - Monitoring and QA/QC requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-day anaerobic biodegradation test as specified in paragraph (b)(4)(i) of this section or by estimating...) of this section. (i) Perform an anaerobic biodegradation test and determine the DOC value of a waste... minimum of a 60-day anaerobic biodegradation test. Consensus-based standards organizations include, but...

40 CFR 265.1083 - Standards: General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 265.1084(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 265.1083 - Standards: General.

Code of Federal Regulations, 2014 CFR

2014-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 265.1084(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

40 CFR 264.1082 - Standards: General.

Code of Federal Regulations, 2013 CFR

2013-07-01

... process is equal to or greater than 95 percent, and the organic biodegradation efficiency (Rbio) for the... biodegradation efficiency for the process shall be determined using the procedures specified in § 264.1083(b) of this subpart. (B) The total actual organic mass biodegradation rate (MRbio) for all hazardous waste...

Diversity of Cellulolytic Microbes and the Biodegradation of Municipal Solid Waste by a Potential Strain

PubMed Central

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

Apparatus and method for biological purification of waste

DOEpatents

Lucido, John A.; Keenan, Daniel; Premuzic, Eugene T.; Lin, Mow S.; Shelenkova, Ludmila

1998-11-24

An apparatus is disclosed for containing a microorganism culture in an active exponential growth and delivering a supply of microorganisms to an environment containing wastes for bio-augmenting the biodegradation of the wastes. The apparatus comprises a bioreactor and an operably connected controller. The bioreactor has a bioreactor chamber for containing a supply of microorganisms, a second chamber for containing a supply of water and inorganic nutrients, and a third chamber for containing a supply of organic nutrients. The bioreactor is operably connected to the controller in which a first pump is operably connected in fluid communication between the bioreactor chamber and the second chamber and third chamber, and a second pump is operably connected in fluid communication between the bioreactor chamber and the environment containing wastes to be biodegraded. The controller further includes a timer and regulator operably connected to the first and second pumps to effectively maintain the microorganisms in exponential growth in the bioreactor chamber and to deliver microorganisms to an environment to be treated. Also, disclosed is a method for bio-augmenting the biodegradation of wastes.

Apparatus and method for biological purification of waste

DOEpatents

Lucido, J.A.; Keenan, D.; Premuzic, E.T.; Lin, M.S.; Shelenkova, L.

1998-11-24

An apparatus is disclosed for containing a microorganism culture in an active exponential growth and delivering a supply of microorganisms to an environment containing wastes for bio-augmenting the biodegradation of the wastes. The apparatus comprises a bioreactor and an operably connected controller. The bioreactor has a bioreactor chamber for containing a supply of microorganisms, a second chamber for containing a supply of water and inorganic nutrients, and a third chamber for containing a supply of organic nutrients. The bioreactor is operably connected to the controller in which a first pump is operably connected in fluid communication between the bioreactor chamber and the second chamber and third chamber, and a second pump is operably connected in fluid communication between the bioreactor chamber and the environment containing wastes to be biodegraded. The controller further includes a timer and regulator operably connected to the first and second pumps to effectively maintain the microorganisms in exponential growth in the bioreactor chamber and to deliver microorganisms to an environment to be treated. Also, disclosed is a method for bio-augmenting the biodegradation of wastes. 7 figs.

Bioreactor tests preliminary to landfill in situ aeration: A case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raga, Roberto, E-mail: roberto.raga@unipd.it; Cossu, Raffaello

Highlights: ► Carbon and nitrogen mass balances in aerated landfill simulation reactors. ► Waste stabilization in aerated landfill simulation reactors. ► Effect of temperature on biodegradation processes in aerated landfills. - Abstract: Lab scale tests in bioreactor were carried out in the framework of the characterization studies of a landfill where in situ aeration (possibly followed by landfill mining) had been proposed as part of the novel waste management strategy in a region in northern Italy. The tests were run to monitor the effects produced by aerobic conditions at different temperatures on waste sampled at different depths in the landfill,more » with focus on the carbon and nitrogen conversion during aeration. Temperatures ranging from 35 to 45 °C were chosen, in order to evaluate possible inhibition of biodegradation processes (namely nitrification) at 45 °C in the landfill. The results obtained showed positive effects of the aeration on leachate quality and a significant reduction of waste biodegradability. Although a delay of biodegradation processes was observed in the reactor run at 45 °C, biodegradation rates increased after 2 months of aeration, providing very low values of the relevant parameters (as in the other aerated reactors) by the end of the study. Mass balances were carried out for TOC and N-NH{sub 4}{sup +}; the findings obtained were encouraging and provided evidence of the effectiveness of carbon and nitrogen conversion processes in the aerated landfill simulation reactors.« less

Natural attenuation of trichloroethylene in fractured shale bedrock.

PubMed

Lenczewski, M; Jardine, P; McKay, L; Layton, A

2003-07-01

This paper describes one of the first well-documented field examples of natural attenuation of trichloroethylene (TCE) in groundwater in a fractured shale bedrock. The study was carried out adjacent to a former waste burial site in Waste Area Grouping 5 (WAG5) on the Oak Ridge Reservation, Oak Ridge, TN. A contaminant plume containing TCE and its daughter products were detected downgradient from the buried waste pits, with most of the contamination occurring in the upper 6 m of the bedrock. The monitoring well array consists of a 35-m-long transect of multilevel sampling wells, situated along a line between the waste pits and a seep which discharges into a small stream. Concentrations of volatile organic carbons (VOCs) were highest in the waste trenches and decreased with distance downgradient towards the seep. Sampling wells indicated the presence of overlapping plumes of TCE, cis-dichloroethylene (cDCE), vinyl chloride (VC), ethylene, ethane, and methane, with the daughter products extending further downgradient than the parent (TCE). This type of distribution suggests anaerobic biodegradation. Measurements of redox potential at the site indicated that iron-reduction, sulfate reduction, and potentially methanogensis were occurring and are conducive to dechlorination of TCE. Bacteria enrichment of groundwater samples revealed the presence of methanotrophs, methanogens, iron-reducing bacteria and sulfate-reducing bacteria, all of which have previously been implicated in anaerobic biodegradation of TCE. 16S rDNA sequence from DNA extracted from two wells were similar to sequences of organisms previously implicated in the anaerobic biodegradation of chlorinated solvents. The combined data strongly suggest that anaerobic biodegradation of the highly chlorinated compounds is occurring. Aerobic biodegradation may also be occurring in oxygenated zones, including near a seep where groundwater exits the site, or in the upper bedrock during seasonal fluctuations in water table elevation and oxygen levels.

Biodegradability of leachates from Chinese and German municipal solid waste*

PubMed Central

Selic, E.; Wang, Chi; Boes, N.; Herbell, J.D.

2007-01-01

The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water. PMID:17173357

Biodegradability of leachates from Chinese and German municipal solid waste.

PubMed

Selic, E; Wang, Chi; Boes, N; Herbell, J D

2007-01-01

The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.

Production of biodegradable plastic by polyhydroxybutyrate (PHB) accumulating bacteria using low cost agricultural waste material.

PubMed

Getachew, Anteneh; Woldesenbet, Fantahun

2016-12-12

Polyhydroxybutyrates (PHBs) are macromolecules synthesized by bacteria. They are inclusion bodies accumulated as reserve materials when the bacteria grow under different stress conditions. Because of their fast degradability under natural environmental conditions, PHBs are selected as alternatives for production of biodegradable plastics. The aim of this work was to isolate potential PHB producing bacteria, evaluate PHB production using agro-residues as carbon sources. Among fifty bacterial strains isolated from different localities, ten PHB accumulating strains were selected and compared for their ability to accumulate PHB granules inside their cells. Isolate Arba Minch Waste Water (AWW) identified as Bacillus spp was found to be the best producer. The optimum pH, temperature, and incubation period for best PHB production by the isolate were 7, 37 °C, and 48 h respectively at 150 rpm. PHB production was best with glucose as carbon source and peptone as nitrogen source. The strain was able to accumulate 55.6, 51.6, 37.4 and 25% PHB when pretreated sugar cane bagasse, corn cob, teff straw (Eragrostis tef) and banana peel were used as carbon sources respectively. Fourier transform-infrared authentication results of the extracted and purified PHB identified its functional units as C-H, CH 2 , C=O and C-O groups. UV-Vis spectrophotometric analysis and biodegradability test confirmed the similarity of the extract with standard PHB and its suitability for bioplastic production. The isolated Bacillus sp can be used for feasible production of PHB using agro-residues especially sugarcane bagasse which can reduce the production cost in addition to reducing the disposal problem of these substrates. The yield of PHB can further be boosted by optimization of production parameters as substrates.

Biogas production from Pongamia biomass wastes and a model to estimate biodegradability from their composition.

PubMed

Gunaseelan, Victor Nallathambi

2014-02-01

In this study, I investigated the chemical characteristics, biochemical methane potential, conversion kinetics and biodegradability of untreated and NaOH-treated Pongamia plant parts, and pod husk and press cake from the biodiesel industry to evaluate their suitability as an alternative feedstock for biogas production. The untreated Pongamia seeds exhibited the maximum CH4 yield of 473 ml g (-1) volatile solid (VS) added. Yellow, withered leaves gave a yield as low as 122 ml CH4 g (-1) VS added. There were significant variations in the CH4 production rate constants, which ranged from 0.02 to 0.15 d (-1), and biodegradability, which ranged from 0.25 to 0.98. NaOH treatment of leaf and pod husk, which were highly rich in fibers, increased the yields by 15-22% and CH4 production rate constants by 20-75%. Utilization of Pongamia wastes in biogas digesters not only influences the economics of biodiesel production but also yields CH4 fuel and protects the environment. The experimental data from this study were used to develop a multiple regression model, which could estimate biodegradability based on biochemical characteristics. The model predicted the biodegradability of previously published biomass wastes (r(2) = 0.88) from their biochemical composition. The theoretical CH4 yields estimated as 350 ml g(-1) chemical oxygen demand destroyed are much higher than the experimental yields as 100% biodegradability is assumed for each substrate. Upon correcting the theoretical CH4 yields with biodegradability data obtained from chemical analyses of substrates, their ultimate CH4 yields could be predicted rapidly.

Adsorption of aquaculture pollutants using a sustainable biopolymer.

PubMed

Zadinelo, Izabel Volkweis; Dos Santos, Lilian Dena; Cagol, Luana; de Muniz, Graciela Inês Bolzón; de Souza Neves Ellendersen, Luciana; Alves, Helton José; Bombardelli, Robie Allan

2018-02-01

Intensive aquaculture needs to adopt techniques that are able to contribute towards sustainability. Closed systems that employ water recirculation can combine intensive production with environmental sustainability, since there is no exchange of water or discharge of effluents into the environment. In order to achieve this, effective filtration systems are required to ensure that the water quality is satisfactory for the cultivation of aquatic organisms. Chitosan, an industrial waste material derived from crustacean farming, is a renewable natural material that is biodegradable and possesses adsorbent characteristics. In this work, chitosan foam was incorporated in filters and was evaluated as an adsorbent of aquaculture pollutants, adding value to the material and at the same time providing a use for industrial waste. The foam was characterized by scanning electron microscopy and energy dispersive spectroscopy, apparent density, and water absorption capacity. It was used to remove ammonia, nitrite, orthophosphate, and turbidity from aquaculture effluents. The foam consisted of a bilayer with smooth and porous sides, which presented low density, flexibility, and high water absorption capacity. The best proportion of the foam, in terms of the mass of foam per volume of solution (% m v -1 ), was 0.10, which resulted in removal of 32.8, 57.2, 89.5, and 99.9% of ammonia, nitrite, orthophosphate, and turbidity, respectively. This biopolymer produced is biodegradable, and when saturated with organic compounds from aquaculture, and no longer suitable for reuse as a filter material, it can be employed as a fertilizer, hence closing the sustainability cycle of the aquaculture production chain.

WASTE STABILIZATION FUNDAMENTALS FOR BIOREACTOR LANDFILLS

EPA Science Inventory

Waste stabilization is the process where putrescible waste is biodegraded by microorganisms resulting in an end-product being a relatively inert substrate (e.g., like compost). When exposed to moisture, biologically stabilized waste should not produce substantial quantitie...

Electrospinning of Biodegradable and Biocompatible Nanofiber Patches from Solutions of ``Green'' Materials for Plant Protection against Fungi Attack

NASA Astrophysics Data System (ADS)

Sett, Soumyadip; Lee, Minwook; Yarin, Alexander; Moghadam, S. M. Alavi; Meinke, Matthias; Schroeder, Wolfgang

2015-11-01

Biodegradable and biocompatible soy protein/petroleum-derived polymer monolithic fibers containing adhesives were electrospun on commercial rayon pads. The polymers used, PVA and PCL, are widely used in the biomedical industry, including such applications as drug delivery and scaffold manufacturing. Soy protein is an abundant waste of SoyDiesel production, and is widely used as a nutrient. The soy content in our fibers was as high as 40% w/w. Four different adhesives, including ordinary wood glue, repositionable glue and FDA-approved pressure-sensitive glue were used for electrospinning and electrospraying. The normal and shear adhesive strengths of the patches developed in this work were measured and compared. The adhesive strength was sufficient enough to withstand normal atmospheric conditions. These biodegradable and biocompatible nano-textured patches are ready to be used on prune locations without being carried away by wind and will protect plants against fungi attack at these locations, preventing diseases like Vine Decline.

Degradation of Oxo-Biodegradable Plastic by Pleurotus ostreatus

PubMed Central

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Nunes, Mateus Dias; da Silva, Marliane de Cássia Soares; Kasuya, Maria Catarina Megumi

2013-01-01

Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate. PMID:23967057

Degradation of oxo-biodegradable plastic by Pleurotus ostreatus.

PubMed

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Nunes, Mateus Dias; da Silva, Marliane de Cássia Soares; Kasuya, Maria Catarina Megumi

2013-01-01

Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate.

Making Plant-Support Structures From Waste Plant Fiber

NASA Technical Reports Server (NTRS)

Morrow, Robert C.; < oscjmocl. < attjew K/; {ertzbprm. A,amda; Ej (e. Cjad); Hunt, John

2006-01-01

Environmentally benign, biodegradable structures for supporting growing plants can be made in a process based on recycling of such waste plant fiber materials as wheat straw or of such derivative materials as paper and cardboard. Examples of structures that can be made in this way include plant plugs, pots, planter-lining mats, plant fences, and root and shoot barriers. No chemical binders are used in the process. First, the plant material is chopped into smaller particles. The particles are leached with water or steam to remove material that can inhibit plant growth, yielding a fibrous slurry. If the desired structures are plugs or sheets, then the slurry is formed into the desired shapes in a pulp molding subprocess. If the desired structures are root and shoot barriers, pots, or fences, then the slurry is compression-molded to the desired shapes in a heated press. The processed materials in these structures have properties similar to those of commercial pressboard, but unlike pressboard, these materials contain no additives. These structures have been found to withstand one growth cycle, even when wet

Municipal solid waste characterization and quantification as a measure towards effective waste management in Ghana.

PubMed

Miezah, Kodwo; Obiri-Danso, Kwasi; Kádár, Zsófia; Fei-Baffoe, Bernard; Mensah, Moses Y

2015-12-01

Reliable national data on waste generation and composition that will inform effective planning on waste management in Ghana is absent. To help obtain this data on a regional basis, selected households in each region were recruited to obtain data on rate of waste generation, physical composition of waste, sorting and separation efficiency and per capita of waste. Results show that rate of waste generation in Ghana was 0.47 kg/person/day, which translates into about 12,710 tons of waste per day per the current population of 27,043,093. Nationally, biodegradable waste (organics and papers) was 0.318 kg/person/day and non-biodegradable or recyclables (metals, glass, textiles, leather and rubbers) was 0.096 kg/person/day. Inert and miscellaneous waste was 0.055 kg/person/day. The average household waste generation rate among the metropolitan cities, except Tamale, was high, 0.72 kg/person/day. Metropolises generated higher waste (average 0.63 kg/person/day) than the municipalities (0.40 kg/person/day) and the least in the districts (0.28 kg/person/day) which are less developed. The waste generation rate also varied across geographical locations, the coastal and forest zones generated higher waste than the northern savanna zone. Waste composition was 61% organics, 14% plastics, 6% inert, 5% miscellaneous, 5% paper, 3% metals, 3% glass, 1% leather and rubber, and 1% textiles. However, organics and plastics, the two major fractions of the household waste varied considerably across the geographical areas. In the coastal zone, the organic waste fraction was highest but decreased through the forest zone towards the northern savanna. However, through the same zones towards the north, plastic waste rather increased in percentage fraction. Households did separate their waste effectively averaging 80%. However, in terms of separating into the bin marked biodegradables, 84% effectiveness was obtained whiles 76% effectiveness for sorting into the bin labeled other waste was achieved. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Textile Wastes.

ERIC Educational Resources Information Center

Talbot, R. S.

1978-01-01

Presents a literature review of wastes from textile industry, covering publications of 1977. This review covers studies such as removing heavy metals in textile wastes, and the biodegradability of six dyes. A list of references is also presented. (HM)

Biodegradation of polystyrene wastes in yellow mealworms (larvae of Tenebrio molitor Linnaeus): Factors affecting biodegradation rates and the ability of polystyrene-fed larvae to complete their life cycle.

PubMed

Yang, Shan-Shan; Brandon, Anja Malawi; Andrew Flanagan, James Christopher; Yang, Jun; Ning, Daliang; Cai, Shen-Yang; Fan, Han-Qing; Wang, Zhi-Yue; Ren, Jie; Benbow, Eric; Ren, Nan-Qi; Waymouth, Robert M; Zhou, Jizhong; Criddle, Craig S; Wu, Wei-Min

2018-01-01

Commercial production of polystyrene (PS) -a persistent plastic that is not biodegradable at appreciable rates in most environments-has led to its accumulation as a major contaminant of land, rivers, lakes, and oceans. Recently, however, an environment was identified in which PS is susceptible to rapid biodegradation: the larval gut of Tenebrio molitor Linnaeus (yellow mealworms). In this study, we evaluate PS degradation capabilities of a previously untested strain of T. molitor and assess its survival and PS biodegradation rates for a range of conditions (two simulated food wastes, three temperatures, seven PS waste types). For larvae fed PS alone, the %PS removed in the short (12-15 h) residence time of the mealworm gut gradually increased for 2-3 weeks then stabilized at values up to 65%. Thirty two-day survival rates were >85% versus 54% for unfed larvae. For mealworms fed ∼10% w/w PS and ∼90% bran, an agricultural byproduct, rates of PS degradation at 25 °C nearly doubled compared to mealworms fed PS alone. Polymer residues in the frass showed evidence of partial depolymerization and oxidation. All of the tested PS wastes degraded, with the less dense foams degrading most rapidly. Mealworms fed bran and PS completed all life cycle stages (larvae, pupae, beetles, egg), and the second generation had favorable PS degradation, opening the door for selective breeding. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biodegradation of plastics.

PubMed

Shimao, M

2001-06-01

Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. Recent work has included studies of the distribution of synthetic polymer-degrading microorganisms in the environment, the isolation of new microorganisms for biodegradation, the discovery of new degradation enzymes, and the cloning of genes for synthetic polymer-degrading enzymes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuniyal, Jagdish C.; Jain, Arun P.; Shannigrahi, Ardhendu S

Solid waste generation in sensitive tourist areas of the Indian Himalayan region is approaching that of some metro cities of the country. The present study showed {approx}288 g waste generation visitor{sup -1} day{sup -1} compared with the nation-wide average of 350 g capita{sup -1} day{sup -1}. About 29 metric tonnes (MT) solid waste is generated along a distance of about 19-km trek (a stretch of land or distance between two or more places covered by a walk) during a 4-month tourist season every year. Treks and trek stalls are the two major places where the visitors generate solid waste. Wastemore » estimated from stalls accounted for about 51% by weight of the total waste generation in the trekking region. The native villagers generally construct stalls every year to meet the requirement of visitors going to Valley of Flowers (VOF) and Hemkund Sahib. The average annual results of 2 years (or equivalent to the average of one, 4-month tourist season for the region) showed non-biodegradable waste (NBW) to be 96.3% by weight whereas biodegradable waste (BW) amounted to merely 3.7%. From management point of view of the government, 96% NBW could easily be reused and recycled. Nevertheless, the need is to manage this waste by bringing it from the trekking areas to the road head (Govind Ghat) first and then to transport it to adjacent recycling centers. Cold drink glass bottles (68%), plastic (26%) and metal (2%) were the major items contributing to non-biodegradable waste. The remaining organic waste could be used as feedstock for composting. A well coordinated effort of public participation is necessary at all the levels for managing waste. There is a need to educate the visitors to instill in them the habit of considering discarded waste as potentially valuable and manageable.« less

Biodegradation of rocket propellent waste, ammonium perchlorate

NASA Technical Reports Server (NTRS)

Naqui, S. M. Z.

1975-01-01

The impact of the biodegradation rate of ammonium perchlorate on the environment was studied in terms of growth, metabolic rate, and total biomass of selected animal and plant species. Brief methodology and detailed results are presented.

[Investigation and countermeasures analysis of catering waste in southern city in China].

PubMed

Xu, Dong; Shen, Dong-Sheng; Feng, Hua-Jun; Wang, Mei-Zhen; Deng, You-Hua

2011-07-01

To find out a suitable way for catering food waste treatment, the waste characteristics from Chinese restaurant, Chinese canteen and western-style canteen in 4 seasons have been investigated. The results showed the average moisture content of the food waste was more than 60%, with more than 87% of VS/TS and the pH range of 4.64-6.98. The contents of organic components were high, the contents of fat and protein and carbohydrate were 16.98% - 38.92%, 6.58% - 11.65% and 46.27% - 68.28%, respectively. It implied the food waste could be easily bio-degraded. The salt content was 0.69% - 2.44%, with total P content of 0.13% - 0.30%. It suggested high content of salt could limit the efficiency of bio-degradation. Based on all above characteristics, separated collection and two-phase anaerobic digestion were considered to be a suitable ways for catering food waste treatment.

Settlement behavior of municipal solid waste due to internal and external environmental factors in a lysimeter.

PubMed

Melo, Márcio C; Caribé, Rômulo M; Ribeiro, Libânia S; Sousa, Raul B A; Monteiro, Veruschka E D; de Paiva, William

2016-12-05

Long-term settlement magnitude is influenced by changes in external and internal factors that control the microbiological activity in the landfill waste body. To improve the understanding of settlement phenomena, it is instructive to study lysimeters filled with MSW. This paper aims to understand the settlement behavior of MSW by correlating internal and external factors that influence waste biodegradation in a lysimeter. Thus, a lysimeter was built, instrumented and filled with MSW from the city of Campina Grande, the state of Paraíba, Brazil. Physicochemical analysis of the waste (from three levels of depth of the lysimeter) was carried out along with MSW settlement measurements. Statistical tools such as descriptive analysis and principal component analysis (PCA) were also performed. The settlement/compression, coefficient of variation and PCA results indicated the most intense rate of biodegradation in the top layer. The PCA results of intermediate and bottom levels presented fewer physicochemical and meteorological variables correlated with compression data in contrast with the top layer. It is possible to conclude that environmental conditions may influence internal indicators of MSW biodegradation, such as the settlement.

Method for biological purification

DOEpatents

Lucido, John A.; Keenan, Daniel; Premuzic, Eugene T.; Lin, Mow S.; Shelenkova, Ludmila

2001-03-27

An apparatus is disclosed for containing a microorganism culture in an active exponential growth and delivering a supply of microorganisms to an environment containing wastes for bio-augmenting the biodegradation of the wastes. The apparatus comprises a bioreactor and an operably connected controller. The bioreactor has a bioreactor chamber for containing a supply of microorganisms, a second chamber for containing a supply of water and inorganic nutrients, and a third chamber for containing a supply of organic nutrients. The bioreactor is operably connected to the controller in which a first pump is operably connected in fluid communication between the bioreactor chamber and the second chamber and third chamber, and a second pump is operably connected in fluid communication between the bioreactor chamber and the environment containing wastes to be biodegraded. The controller further includes a timer and regulator operably connected to the first and second pumps to effectively maintain the microorganisms in exponential growth in the bioreactor chamber and to deliver microorganisms to an environment to be treated. Also, disclosed is a method for bio-augmenting the biodegradation of wastes.

Investigation of the combustion kinetics and polycyclic aromatic hydrocarbon emissions from polycaprolactone combustion.

PubMed

Chien, Y C; Yang, S H

2013-01-01

Polycaprolactone (PCL) is one of the most attractive biodegradable plastics that has been widely used in medicine and agriculture fields. Because of the large increase in biodegradable plastics usage, the production of waste biodegradable plastics will be increasing dramatically, producing a growing environmental problem. Generally, waste PCL is collected along with municipal solid wastes and then incinerated. This study investigates the combustion kinetics and emission factors of 16 US Environmental Protection Agency (EPA) priority polycyclic aromatic hydrocarbons (PAHs) in the PCL combustion. Experimentally, two reactions are involved in the PCL combustion process, possibly resulting in the emission of carbon dioxide, propanal, protonated caprolactone and very small amounts of PAH produced by incomplete combustion. The intermediate products may continuously be oxidized to form CO2. The emission factors for 16 US EPA priority PAHs are n.d. -2.95 microg/g, which are much lower than those of poly lactic acid and other plastics combustion. The conversion of PCL is 100%. Results from this work suggest that combustion is a good choice for the waste PCL disposal.

Introduction of Environmentally Degradable Parameters to Evaluate the Biodegradability of Biodegradable Polymers

PubMed Central

Yang, Chao; Song, Cunjiang; Geng, Weitao; Li, Qiang; Wang, Yuanyuan; Kong, Meimei; Wang, Shufang

2012-01-01

Environmentally Degradable Parameter (Ed K) is of importance in the describing of biodegradability of environmentally biodegradable polymers (BDPs). In this study, a concept Ed K was introduced. A test procedure of using the ISO 14852 method and detecting the evolved carbon dioxide as an analytical parameter was developed, and the calculated Ed K was used as an indicator for the ultimate biodegradability of materials. Starch and polyethylene used as reference materials were defined as the Ed K values of 100 and 0, respectively. Natural soil samples were inoculated into bioreactors, followed by determining the rates of biodegradation of the reference materials and 15 commercial BDPs over a 2-week test period. Finally, a formula was deduced to calculate the value of Ed K for each material. The Ed K values of the tested materials have a positive correlation to their biodegradation rates in the simulated soil environment, and they indicated the relative biodegradation rate of each material among all the tested materials. Therefore, the Ed K was shown to be a reliable indicator for quantitatively evaluating the potential biodegradability of BDPs in the natural environment. PMID:22675455

Aerobic biodegradability of methyldiethanolamine (MDEA) used in natural gas sweetening plants in batch tests and continuous flow experiments.

PubMed

Fürhacker, M; Pressl, A; Allabashi, R

2003-09-01

Mixtures of different amines including tertiary amines (methyldiethanolamine, MDEA) are commonly used for the removal of CO2 from gas mixtures or in gas sweetening processes for the extraction of CO2 and H2S. The absorber solutions used can be released into the industrial waste water due to continuous substitution of degraded MDEA, periodically cleaning processes or an accidental spill. In this study, the aerobic biodegradability of MDEA was investigated in a standardised batch test and a continuous flow experiment (40 l/d). The results of the batch test indicated that the MDEA-solution was non-biodegradable during the test period of 28 days, whereas the continuous flow experiments showed biodegradation of more than 96% based on TOC-measurements. This was probably due to the adaptation of the microorganisms to this particular waste water contamination during continuous flow experiment.

Evaluation of anaerobic co-digestion of dairy manure with food wastes via bio-methane potential assay and CSTR reactor.

PubMed

Ye, Yulin; Zamalloa, Carlos; Lin, Hongjian; Yan, Mi; Schmidt, David; Hu, Bo

2015-01-01

The introduction of food wastes into anaerobic digestion (AD) brings a promising scenario of increasing feedstock availability and overall energy production from AD. This study evaluated the biodegradability and methane potential from co-digestion of two typical food wastes, kitchen waste and chicken fat, with dairy manure. For single substrate, the bio-methane potential assays showed that kitchen waste had the highest methane yield of 352 L-CH4 kg(-1)-VS added, 92% more than dairy manure alone. Chicken fat at the same Volatile Solid (VS) level (2 g L(-1)) inhibited bio-methane production. Addition of kitchen waste and chicken fat to a VS percentage of up to 40% improved overall methane yield by 44% and 34%, respectively. Synergistic effect was observed when either combining two or three substrates as AD feedstock, possibly as a result of increased biodegradability of organic materials in chicken fat and kitchen waste compared with dairy manure. Addition of chicken fat improved methane yield more than kitchen waste. However, addition of chicken fat VS over 0.8 g L(-1) should be cautiously done because it may cause reactor failure due to decrease in pH. The maximum methane yield was 425 L-CH4 kg(-1)-VS, achieved at a VS ratio of 2:2:1 for kitchen waste, chicken fat, and dairy manure. Results from batch AD experiment demonstrated that supplementing dairy manure to chicken fat and/or kitchen waste improved alkalinity of substrate due to the inclusion of more titratable bases in dairy manure, and therefore stabilized the methanogenesis and substantially improved biogas yield. A mixture of substrates of kitchen waste, chicken fat, and dairy manure at a ratio of 1:1:3 was fed to a continuously stirred tank reactor operated at organic loading rates of 3.28, 6.55, and 2.18 g-COD L(-1)-day (hydraulic retention time of 20, 10, and 30 days, respectively) under mesophilic condition, and methane production rate reached 0.65, 0.95, and 0.34 L-CH4 L(-1)-reactor-day.

A novel strategy for producing compost with enhanced biopesticide properties through solid-state fermentation of biowaste and inoculation with Bacillus thuringiensis.

PubMed

Ballardo, Cindy; Barrena, Raquel; Artola, Adriana; Sánchez, Antoni

2017-12-01

In the framework of a circular economy, organic solid wastes are considered to be resources useful for obtaining value-added products. Among other potential uses, biodegradable wastes from agricultural, industrial, and domestic sources are being studied to obtain biopesticides through solid-state fermentation (SSF), mainly at the laboratory scale. The suitability of biowaste (source-selected organic fraction of municipal solid waste) for use as a substrate for Bacillus thuringiensis (Bt) growth under non-sterile conditions in a 10 L SSF reactor was determined in this study. An operational strategy for setting up a semi-continuous process yielding a stabilised organic compost-like material enriched with Bt suitable for use as a soil amendment was developed. Concentrations of 1.7·10 7 -2.2·10 7 and 1.3·10 7 -2.1·10 7  CFU g -1 DM for Bt viable cells and spores, respectively, were obtained in the final material. As the results confirmed, Bt-enriched compost-like material with potential biopesticide properties can be produced from non-sterile biowaste. Copyright © 2017 Elsevier Ltd. All rights reserved.

Green waste cooking oil-based rigid polyurethane foam

NASA Astrophysics Data System (ADS)

Enderus, N. F.; Tahir, S. M.

2017-11-01

Polyurethane is a versatile polymer traditionally prepared using petroleum-based raw material. Petroleum, however, is a non-renewable material and polyurethane produced was found to be non-biodegradable. In quest for a more environmentally friendly alternative, wastecooking oil, a highly abundant domestic waste with easily derivatized structure, is a viable candidate to replace petroleum. In this study,an investigation to determine physical and chemical properties of rigid polyurethane (PU) foam from waste cooking oil (WCO) was carried out. WCO was first adsorbed by using coconut husk activated carbon adsorbent prior to be used for polyol synthesis. The purified WCO was then used to synthesize polyol via transesterification reaction to yield alcohol groups in the WCO chains structure. Finally, the WCO-based polyol was used to prepare rigid PU foam. The optimum formulation for PU formation was found to be 90 polyol: 60 glycerol: 54 water: 40 diethanolamine: 23 diisocyanate. The rigid PU foam has density of 208.4 kg/m3 with maximum compressive strength and capability to receive load at 0.03 MPa and 0.09 kN, respectively. WCO-based PU can potentially be used to replace petroleum-based PU as house construction materials such as insulation panels.

Sustainable hybrid photocatalysts: titania immobilized on ...

EPA Pesticide Factsheets

This review comprises the preparation, properties and heterogeneous photocatalytic applications of TiO2 immobilized on carbon materials derived from earth-abundant, renewable and biodegradable agricultural residues and sea food waste resources. The overview provides key scientific insights into widely used TiO2 supported on carbonaceous materials emanating from biopolymeric materials such as lignin, cellulose, cellulose acetate, bacterial cellulose, bamboo, wood, starch, chitosan and agricultural residues (biochar, charcoal, activated carbon and their magnetic forms, coal fly ash) or seafood wastes namely eggshell, clamshell and fish scales; materials that serve as a support/template for TiO2. Heightened awareness and future inspirational developments for the valorisation of various forms of carbonaceous functional materials is the main objective. This appraisal abridges various strategies available to upgrade renewable carbon-based feedstock via the generation of sustainable TiO2/carbon functional materials and provides remarks on their future prospects. Hopefully, this will stimulate the development of efficient and novel composite photocatalysts and engender the necessary knowledge base for further advancements in greener photocatalytic technologies. Prepared as a Critical Review for the Royal Society of Chemistry (RSC) journal, Green Chemistry. This review discusses the sustainable use of earth-abundant materials exemplified by Titanium dioxide and carbon.

40 CFR 61.355 - Test methods, procedures, and compliance provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... entering an enhanced biodegradation unit, as defined in § 61.348(b)(2)(ii)(B), shall not be included in the... are met: (i) The benzene concentration for each waste stream entering the enhanced biodegradation unit...

40 CFR 61.355 - Test methods, procedures, and compliance provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... entering an enhanced biodegradation unit, as defined in § 61.348(b)(2)(ii)(B), shall not be included in the... are met: (i) The benzene concentration for each waste stream entering the enhanced biodegradation unit...

40 CFR 61.355 - Test methods, procedures, and compliance provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... entering an enhanced biodegradation unit, as defined in § 61.348(b)(2)(ii)(B), shall not be included in the... are met: (i) The benzene concentration for each waste stream entering the enhanced biodegradation unit...

40 CFR 61.355 - Test methods, procedures, and compliance provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... entering an enhanced biodegradation unit, as defined in § 61.348(b)(2)(ii)(B), shall not be included in the... are met: (i) The benzene concentration for each waste stream entering the enhanced biodegradation unit...

40 CFR 61.355 - Test methods, procedures, and compliance provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... entering an enhanced biodegradation unit, as defined in § 61.348(b)(2)(ii)(B), shall not be included in the... are met: (i) The benzene concentration for each waste stream entering the enhanced biodegradation unit...

Current-use and organochlorine pesticides and polychlorinated biphenyls in the biodegradable fraction of source separated household waste, compost, and anaerobic digest.

PubMed

Hellström, Anna; Nilsson, Marie-Louise; Kylin, Henrik

2011-01-01

Several current-use (≤ 80 ng g⁻¹ dry weight) and organochlorine pesticides (≤ 15 ng g⁻¹ dry weight) and polychlorinated biphenyls (≤ 18 ng g⁻¹ dry weight) were found in the biodegradable fraction of source separated household waste, compost, and/or anaerobic digestate. The degradation rates of individual compounds differ depending on the treatment. Dieldrin and pentachloroaniline, e.g., degrade more rapidly than the waste is mineralized and accumulates in the products after all treatments. Many organochlorines degrade at the same rate as the waste and have the same concentrations in the waste and products. Chlorpyrifos degrades slower than the waste and accumulates in all products and ethion during anaerobic digestion. The polychlorinated biphenyls and some pesticides show different degradations rates relative the waste during different processes. Understanding the degradation of the contaminants under different conditions is necessary to develop quality criteria for the use of compost and digest.

Material Processing and Design of Biodegradable Metal Matrix Composites for Biomedical Applications.

PubMed

Yang, Jingxin; Guo, Jason L; Mikos, Antonios G; He, Chunyan; Cheng, Guang

2018-06-04

In recent years, biodegradable metallic materials have played an important role in biomedical applications. However, as typical for the metal materials, their structure, general properties, preparation technology and biocompatibility are hard to change. Furthermore, biodegradable metals are susceptible to excessive degradation and subsequent disruption of their mechanical integrity; this phenomenon limits the utility of these biomaterials. Therefore, the use of degradable metals, as the base material to prepare metal matrix composite materials, it is an excellent alternative to solve the problems above described. Biodegradable metals can thus be successfully combined with other materials to form biodegradable metallic matrix composites for biomedical applications and functions. The present article describes the processing methods currently available to design biodegradable metal matrix composites for biomedical applications and provides an overview of the current existing biodegradable metal systems. At the end, the manuscript presents and discusses the challenges and future research directions for development of biodegradable metallic matrix composites for biomedical purposes.

Changes in bacterial community of anthracene bioremediation in municipal solid waste composting soil*

PubMed Central

Zhang, Shu-ying; Wang, Qing-feng; Wan, Rui; Xie, Shu-guang

2011-01-01

Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in a municipal solid waste (MSW) composting site. Knowledge of changes in microbial structure is useful to identify particular PAH degraders. However, the microbial community in the MSW composting soil and its change associated with prolonged exposure to PAHs and subsequent biodegradation remain largely unknown. In this study, anthracene was selected as a model compound. The bacterial community structure was investigated using terminal restriction fragment length polymorphism (TRFLP) and 16S rRNA gene clone library analysis. The two bimolecular tools revealed a large shift of bacterial community structure after anthracene amendment and subsequent biodegradation. Genera Methylophilus, Mesorhizobium, and Terrimonas had potential links to anthracene biodegradation, suggesting a consortium playing an active role. PMID:21887852

BIOPLUME MODEL FOR CONTAMINANT TRANSPORT AFFECTED BY OXYGEN LIMITED BIODEGRADATION

EPA Science Inventory

Many of the organic pollutants entering ground water are potentially biodegradable in the subsurface. This potential has been demonstrated in aquifers contaminated by wood-creosoting process wastes. The persistence of many of these organic compounds in the subsurface indicated ...

Microbial degradation of low-density polyethylene (LDPE) by Aspergillus clavatus strain JASK1 isolated from landfill soil.

PubMed

Gajendiran, Anudurga; Krishnamoorthy, Sharmila; Abraham, Jayanthi

2016-06-01

Polythene and plastic waste are found to accumulate in the environment, posing a major ecological threat. They are found to be considered non-degradable, once it enters the environment it has been found to remain there indefinitely. However, significant attention has been placed on biodegradable polymer, identification of microbes with degradative potential on plastic material. The aim of the present investigation was to biodegrade low-density polyethylene (LDPE) using potential fungi isolated from landfill soil. Based on 18S rRNA analyses the isolated strain was identified as Aspergillus clavatus. LDPE degradation by A. clavatus was monitored for 90 days of incubation in aqueous medium. The degradation was confirmed by changes in polyethylene weight, CO 2 evolution by Strum test, infrared spectra and morphological changes by SEM and AFM analysis.

Microbial Enzymatic Degradation of Biodegradable Plastics.

PubMed

Roohi; Bano, Kulsoom; Kuddus, Mohammed; Zaheer, Mohammed R; Zia, Qamar; Khan, Mohammed F; Ashraf, Ghulam Md; Gupta, Anamika; Aliev, Gjumrakch

2017-01-01

The renewable feedstock derived biodegradable plastics are important in various industries such as packaging, agricultural, paper coating, garbage bags and biomedical implants. The increasing water and waste pollution due to the available decomposition methods of plastic degradation have led to the emergence of biodegradable plastics and biological degradation with microbial (bacteria and fungi) extracellular enzymes. The microbes utilize biodegradable polymers as the substrate under starvation and in unavailability of microbial nutrients. Microbial enzymatic degradation is suitable from bioremediation point of view as no waste accumulation occurs. It is important to understand the microbial interaction and mechanism involved in the enzymatic degradation of biodegradable plastics under the influence of several environmental factors such as applied pH, thermo-stability, substrate molecular weight and/or complexity. To study the surface erosion of polymer film is another approach for hydrolytic degradation characteristion. The degradation of biopolymer is associated with the production of low molecular weight monomer and generation of carbon dioxide, methane and water molecule. This review reported the degradation study of various existing biodegradable plastics along with the potent degrading microbes (bacteria and fungi). Patents available on plastic biodegradation with biotechnological significance is also summarized in this paper. This paper assesses that new disposal technique should be adopted for the degradation of polymers and further research is required for the economical production of biodegradable plastics along with their enzymatic degradation. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Conversion of post consumer polyethylene to the biodegradable polymer polyhydroxyalkanoate.

PubMed

Guzik, Maciej W; Kenny, Shane T; Duane, Gearoid F; Casey, Eoin; Woods, Trevor; Babu, Ramesh P; Nikodinovic-Runic, Jasmina; Murray, Michael; O'Connor, Kevin E

2014-05-01

A process for the conversion of post consumer (agricultural) polyethylene (PE) waste to the biodegradable polymer medium chain length polyhydroxyalkanoate (mcl-PHA) is reported here. The thermal treatment of PE in the absence of air (pyrolysis) generated a complex mixture of low molecular weight paraffins with carbon chain lengths from C8 to C32 (PE pyrolysis wax). Several bacterial strains were able to grow and produce PHA from this PE pyrolysis wax. The addition of biosurfactant (rhamnolipids) allowed for greater bacterial growth and PHA accumulation of the tested strains. Some strains were only capable of growth and PHA accumulation in the presence of the biosurfactant. Pseudomonas aeruginosa PAO-1 accumulated the highest level of PHA with almost 25 % of the cell dry weight as PHA when supplied with the PE pyrolysis wax in the presence of rhamnolipids. The change of nitrogen source from ammonium chloride to ammonium nitrate resulted in faster bacterial growth and the earlier onset of PHA accumulation. To our knowledge, this is the first report where PE is used as a starting material for production of a biodegradable polymer.

Enrichment and characterization of hydrocarbon-degrading bacteria from petroleum refinery waste as potent bioaugmentation agent for in situ bioremediation.

PubMed

Sarkar, Poulomi; Roy, Ajoy; Pal, Siddhartha; Mohapatra, Balaram; Kazy, Sufia K; Maiti, Mrinal K; Sar, Pinaki

2017-10-01

Intrinsic biodegradation potential of bacteria from petroleum refinery waste was investigated through isolation of cultivable strains and their characterization. Pseudomonas and Bacillus spp. populated the normal cultivable taxa while prolonged enrichment with hydrocarbons and crude oil yielded hydrocarbonoclastic bacteria of genera Burkholderia, Enterobacter, Kocuria, Pandoraea, etc. Strains isolated through enrichment showed assemblages of superior metabolic properties: utilization of aliphatic (C6-C22) and polyaromatic compounds, anaerobic growth with multiple terminal electron acceptors and higher biosurfactant production. Biodegradation of dodecane was studied thoroughly by GC-MS along with detection of gene encoding alkane hydroxylase (alkB). Microcosms bioaugmented with Enterobacter, Pandoraea and Burkholderia strains showed efficient biodegradation (98% TPH removal) well fitted in first order kinetic model with low rate constants and decreased half-life. This study proves that catabolically efficient bacteria resides naturally in complex petroleum refinery wastes and those can be useful for bioaugmentation based bioremediation. Copyright © 2017 Elsevier Ltd. All rights reserved.

DEMONSTRATION BULLETIN: SLURRY BIODEGRADATION, International Technology Corporation

EPA Science Inventory

This technology uses a slurry-phase bioreactor in which the soil is mixed with water to form a slurry. Microorganisms and nutrients are added to the slurry to enhance the biodegradation process, which converts organic wastes into relatively harmless byproducts of microbial metabo...

Single-cell protein from waste cellulose

NASA Technical Reports Server (NTRS)

Dunlap, C. E.; Callihan, C. D.

1973-01-01

The recycle, reuse, or reclamation of single cell protein from liquid and solid agricultural waste fibers by a fermentation process is reported. It is shown that cellulose comprises the bulk of the fibers at 50% to 55% of the dry weight of the refuse and that its biodegradability is of prime importance in the choice of a substrate. The application of sodium hydroxide followed by heat and pressure serves to de-polymerize and disrupt lignin structure while swelling the cellulose to increase water uptake and pore volume. Some of the lignin, hemi-celluloses, ash, and cellulose of the material is hydrolized and solubilized. Introduction of microorganisms to the substrate fibers mixed with nutrients produces continuous fermentation of cellulose for further protein extraction and purification.

Biocompatibility of new drug-eluting biodegradable urethral stent materials.

PubMed

Kotsar, Andres; Nieminen, Riina; Isotalo, Taina; Mikkonen, Joonas; Uurto, Ilkka; Kellomäki, Minna; Talja, Martti; Moilanen, Eeva; Tammela, Teuvo L J

2010-01-01

To investigate the effects of biodegradable stent material (poly-96L/4D-lactic acid [PLA]) on the production of cytokines and other inflammatory mediators in vitro and the biocompatibility of new drug-eluting biodegradable urethral stent materials in vivo. Indomethacin, dexamethasone, and simvastatin were used in the materials. The effects of the biodegradable stent material on cytokines and other inflammatory mediators were measured using the Human Cytokine Antibody Array and enzyme-linked immunosorbent assay in THP-1 cells, with bacterial lipopolysaccharide as a positive control. To assess the biocompatibility of the stent materials, we used muscle implantation. Biodegradable stent materials without drug-eluting properties and silicone and latex were used as controls. The measurements were done at 3 weeks and 3 months. The PLA stent material induced production of inflammatory mediators, especially interleukin-8, tumor necrosis factor-alpha, and transforming growth factor-beta, in vitro. The increase in the production of these mediators with the PLA stent material was smaller than in the cells treated with lipopolysaccharide. In vivo, the effects of the biodegradable materials did not differ at 3 weeks, although, at 3 months, dexamethasone had induced more tissue reactions than had the other materials. At 3 months, fibrosis and chronic inflammatory changes were decreased in the biodegradable material groups compared with the positive control. PLA stent material increased the production of cytokines and other inflammatory mediators less than did positive controls in vitro. The in vivo biocompatibility of the drug-eluting biodegradable materials was better than that of the positive controls. Drug-eluting biodegradable urethral stents could potentially offer a new treatment modality in the future. 2010 Elsevier Inc. All rights reserved.

Biodegradation of nicotine by a newly isolated Pseudomonas stutzeri JZD

NASA Astrophysics Data System (ADS)

Petricevic, Jelena; Gujanicic, Vera; Radic, Danka; Jovicic Petrovic, Jelena; Jovic, Jelena; Raicevic, Vera

2013-04-01

The tobacco-manufacturing process and all activities that use tobacco, produce solid or liquid wastes with high concentrations of nicotine. Nicotine is a significant toxic waste product in tobacco industry. This waste is classified as 'toxic and hazardous' by European Union regulations when the nicotine content exceeds 500 milligrams per kilogram dry weight. Therefore, there is a major environmental requirement to remove nicotine from tobacco wastes. Bioremediation techniques which involve nicotine degradation by microorganisms have attracted attention during the last years, because microorganisms have the potential to reduce nicotine levels in tobacco and to detoxify tobacco wastes. The aim of this study is isolation and identification of nicotine degraded bacteria and optimization of nicotine degradation in laboratory conditions. An aerobic bacterial strain capable of effectively degrading nicotine was isolated from the tobacco industry waste, Serbia. After isolation, the liquid culture was spread onto the solid plates of the nicotine inorganic salt medium using the dilution plate method. Cell morphology of strain was observed by a light microscope and physiological characteristics were determined by Api technique and sequence analyzes of 16S rDNA. This isolate was identified as Pseudomonas stutzeri based on morphology, physiological characteristics, and Apiweb technique. Comparison with sequences available in data library showed the 99% similarity with 16S rDNA gene sequence of the species Pseudomonas stutzeri ( GenBank Acc. No. CP003725). We analyzed the effect of initial nicotine concentration (1g/L, 1.5 g/L, 2.5 g/L) on microbial activity in aim to optimize biodegradation. The effect of cultivation temperature (25°C; 30°C; 37°C) on nicotine degradation by P. stutzeri was evaluated after 24 h of cultivation, with 1.5 g/L nicotine added as the sole carbon source. Effect of biodegradation has depended on initial concentration. During incubation, number of bacteria was increased in all variants of initial concentrations. Nicotine degradation rate increased with increasing cultivation temperature. The optimal temperature was 37°C. The results suggest that the P. stutzeri may be useful for bioremediation of nicotine-polluted waste and confirms its possible application in solving of nicotine contamination problems. Key words: Pseudomonas stutzeri, biodegradation; nicotine; waste

Large-Scale In-situ Experiments to Determine Geochemical Alterations and Microbial Activities at the Geological Repository

NASA Astrophysics Data System (ADS)

Choung, S.; Francis, A. J.; Um, W.; Choi, S.; Kim, S.; Park, J.; Kim, S.

2013-12-01

The countries that have generated nuclear power have facing problems on the disposal of accumulated radioactive wastes. Geological disposal method has been chosen in many countries including Korea. A safety issue after the closure of geological repository has been raised, because microbial activities lead overpressure in the underground facilities through gas production. In particular, biodegradable organic materials derived from low- and intermediate-level radioactive wastes play important role on microbial activities in the geological repository. This study performed large scale in-situ experiments using organic wastes and groundwater, and investigated geochemical alteration and microbial activities at early stage (~63 days) as representative of the period, after closure of the geological repository. The geochemical alteration controlled significantly the microorganism types and populations. Database of the biogeochemical alteration facilitates prediction of radionuclides' mobility and establishment of remedial strategy against unpredictable accidents and hazards at early stage right after closure of the geological repository.

Renewable Biochemical Methane Potential through Anaerobic Co-digestion from Selective Feed Stocks

NASA Astrophysics Data System (ADS)

Thara, K.; Navis Karthika, Ignatius; Dheenadayalan, M. S., Dr

2017-08-01

Biochemical Methane Potential (BMP) analysis provides a measure of the anaerobic biodegradability of a given substrate. BMP test is also used to evaluate the potential biogas (methane) production between various Co-digestion substrates. This test is also used to determine the amount of organic carbon in a given material that can be an aerobically converted to methane-Biogas. Studies were carried out for the production of biogas from the leather solid waste. Co-digestion (simultaneous digestion of two or more substrates) studies were carried out in batch reactor using the fleshing (a solid waste generated during the processing of raw hides or skins into finished leather) along with the fruit and vegetable waste at mesophilic condition 35° C). The anaerobic methanogenic seed sludge prepared separately followed by standard BMP test, which was used as the seed inoculums. Recent research on this topic is reviewed in this current paper.

Energy recovery from solid waste. Volume 2: Technical report. [pyrolysis and biodegradation

NASA Technical Reports Server (NTRS)

Huang, C. J.; Dalton, C.

1975-01-01

A systems analysis of energy recovery from solid waste demonstrates the feasibility of several current processes for converting solid waste to an energy form. The social, legal, environmental, and political factors are considered in depth with recommendations made in regard to new legislation and policy. Biodegradation and thermal decomposition are the two areas of disposal that are considered with emphasis on thermal decomposition. A technical and economic evaluation of a number of available and developing energy-recovery processes is given. Based on present technical capabilities, use of prepared solid waste as a fuel supplemental to coal seems to be the most economic process by which to recover energy from solid waste. Markets are considered in detail with suggestions given for improving market conditions and for developing market stability. A decision procedure is given to aid a community in deciding on its options in dealing with solid waste, and a new pyrolysis process is suggested. An application of the methods of this study are applied to Houston, Texas.

Bioreactor tests preliminary to landfill in situ aeration: a case study.

PubMed

Raga, Roberto; Cossu, Raffaello

2013-04-01

Lab scale tests in bioreactor were carried out in the framework of the characterization studies of a landfill where in situ aeration (possibly followed by landfill mining) had been proposed as part of the novel waste management strategy in a region in northern Italy. The tests were run to monitor the effects produced by aerobic conditions at different temperatures on waste sampled at different depths in the landfill, with focus on the carbon and nitrogen conversion during aeration. Temperatures ranging from 35 to 45°C were chosen, in order to evaluate possible inhibition of biodegradation processes (namely nitrification) at 45°C in the landfill. The results obtained showed positive effects of the aeration on leachate quality and a significant reduction of waste biodegradability. Although a delay of biodegradation processes was observed in the reactor run at 45°C, biodegradation rates increased after 2 months of aeration, providing very low values of the relevant parameters (as in the other aerated reactors) by the end of the study. Mass balances were carried out for TOC and NNH4(+); the findings obtained were encouraging and provided evidence of the effectiveness of carbon and nitrogen conversion processes in the aerated landfill simulation reactors. Copyright © 2012 Elsevier Ltd. All rights reserved.

ANAEROBIC/AEROBIC BIODEGRADATION OF PENTACHLOROPHENOL USING GAC FLUIDIXED BED REACTORS: OPTIMIZATION OF THE EMPTY BED CONTACT TIME

EPA Science Inventory

An integrated reactor system has been developed to remediate pentachlorophenol (PCP) containing wastes using sequential anaerobic and aerobic biodegradation. Anaerobically, PCP was degraded to approximately equimolar concentrations (>99%) of chlorophenol (CP) in a granular activa...

Performance of the lysozyme for promoting the waste activated sludge biodegradability.

PubMed

He, Jun-Guo; Xin, Xiao-Dong; Qiu, Wei; Zhang, Jie; Wen, Zhi-Dan; Tang, Jian

2014-10-01

The fresh waste activated sludge (WAS) from a lab-scale sequencing batch reactor was used to determine the performance of the lysozyme for promoting its biodegradability. The results showed that a strict linear relationship presented between the degree of disintegration (DDM) of WAS and the lysozyme incubation time from 0 to 240min (R(2) was 0.992, 0.995 and 0.999 in accordance with the corresponding lysozyme/TS, respectively). Ratio of net SCOD increase augmented significantly by lysozyme digestion for evaluating the sludge biodegradability changes. Moreover, the protein dominated both in the EPS and SMP. In addition, the logarithm of SMP contents in supernatant presented an increasing trend similar with the ascending logarithmic relation with the lysozyme incubation time from 0 to 240min (R(2) was 0.960, 0.959 and 0.947, respectively). The SMP, especially the soluble protein, had an important contribution to the improvement of WAS biodegradability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Poly β-hydroxybutyrate production by Bacillus subtilis NG220 using sugar industry waste water.

PubMed

Singh, Gulab; Kumari, Anish; Mittal, Arpana; Yadav, Anita; Aggarwal, Neeraj K

2013-01-01

The production of poly β-hydroxybutyrate (PHB) by Bacillus subtilis NG220 was observed utilizing the sugar industry waste water supplemented with various carbon and nitrogen sources. At a growth rate of 0.14 g h(-1) L(-1), using sugar industry waste water was supplemented with maltose (1% w/v) and ammonium sulphate (1% w/v); the isolate produced 5.297 g/L of poly β-hydroxybutyrate accumulating 51.8% (w/w) of biomass. The chemical nature of the polymer was confirmed with nuclear magnetic resonance, Fourier transform infrared, and GC-MS spectroscopy whereas thermal properties were monitored with differential scanning calorimetry. In biodegradability study, when PHB film of the polymer (made by traditional solvent casting technique) was subjected to degradation in various natural habitats like soil, compost, and industrial sludge, it was completely degraded after 30 days in the compost having 25% (w/w) moisture. So, the present study gives insight into dual benefits of conversion of a waste material into value added product, PHB, and waste management.

Biodegradation of the alkaline cellulose degradation products generated during radioactive waste disposal.

PubMed

Rout, Simon P; Radford, Jessica; Laws, Andrew P; Sweeney, Francis; Elmekawy, Ahmed; Gillie, Lisa J; Humphreys, Paul N

2014-01-01

The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7 × 10(-2) hr(-1) (SE ± 2.9 × 10(-3)). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility.

Poly β-Hydroxybutyrate Production by Bacillus subtilis NG220 Using Sugar Industry Waste Water

PubMed Central

Singh, Gulab; Kumari, Anish; Mittal, Arpana; Yadav, Anita; Aggarwal, Neeraj K.

2013-01-01

The production of poly β-hydroxybutyrate (PHB) by Bacillus subtilis NG220 was observed utilizing the sugar industry waste water supplemented with various carbon and nitrogen sources. At a growth rate of 0.14 g h−1 L−1, using sugar industry waste water was supplemented with maltose (1% w/v) and ammonium sulphate (1% w/v); the isolate produced 5.297 g/L of poly β-hydroxybutyrate accumulating 51.8% (w/w) of biomass. The chemical nature of the polymer was confirmed with nuclear magnetic resonance, Fourier transform infrared, and GC-MS spectroscopy whereas thermal properties were monitored with differential scanning calorimetry. In biodegradability study, when PHB film of the polymer (made by traditional solvent casting technique) was subjected to degradation in various natural habitats like soil, compost, and industrial sludge, it was completely degraded after 30 days in the compost having 25% (w/w) moisture. So, the present study gives insight into dual benefits of conversion of a waste material into value added product, PHB, and waste management. PMID:24027767

Eco-Friendly and Biodegradable Biopolymer Chitosan/Y₂O₃ Composite Materials in Flexible Organic Thin-Film Transistors.

PubMed

Du, Bo-Wei; Hu, Shao-Ying; Singh, Ranjodh; Tsai, Tsung-Tso; Lin, Ching-Chang; Ko, Fu-Hsiang

2017-09-03

The waste from semiconductor manufacturing processes causes serious pollution to the environment. In this work, a non-toxic material was developed under room temperature conditions for the fabrication of green electronics. Flexible organic thin-film transistors (OTFTs) on plastic substrates are increasingly in demand due to their high visible transmission and small size for use as displays and wearable devices. This work investigates and analyzes the structured formation of aqueous solutions of the non-toxic and biodegradable biopolymer, chitosan, blended with high-k-value, non-toxic, and biocompatible Y₂O₃ nanoparticles. Chitosan thin films blended with Y₂O₃ nanoparticles were adopted as the gate dielectric thin film in OTFTs, and an improvement in the dielectric properties and pinholes was observed. Meanwhile, the on/off current ratio was increased by 100 times, and a low leakage current was observed. In general, the blended chitosan/Y₂O₃ thin films used as the gate dielectric of OTFTs are non-toxic, environmentally friendly, and operate at low voltages. These OTFTs can be used on surfaces with different curvature radii because of their flexibility.

[Biodegradable synthetic implant materials : clinical applications and immunological aspects].

PubMed

Witte, F; Calliess, T; Windhagen, H

2008-02-01

In the last decade biodegradable synthetic implant materials have been established for various clinical applications. Ceramic materials such as calcium phosphate, bioglass and polymers are now routinely used as degradable implants in the clinical practice. Additionally these materials are now also used as coating materials or as microspheres for controlled drug release and belong to a series of examples for applications as scaffolds for tissue engineering. Because immense local concentrations of degradation products are produced during biodegradation, this review deals with the question whether allergic immune reactions, which have been reported for classical metallic and organic implant materials, also play a role in the clinical routine for synthetic biodegradable materials. Furthermore, possible explanatory theories will be developed to clarify the lack of clinical reports on allergy or sensitization to biodegradable synthetic materials.

Assessment of sanitary landfill leachate characterizations and its impacts on groundwater at Alexandria.

PubMed

Hassan, Ahmed Hossam; Ramadan, Mohamed Hassan

2005-01-01

The total amount of solid waste generated in Alexandria is 2820 tons/d which increases to 3425 tons/day during summer. In the past, 77% of the collected solid wastes was open dumped. The open dumping sites did not have the minimum requirements for pollution control. Following the exacerbation of the problem, the Alexandria Governorate contracted a company to carry out the solid waste management. The contracted company transferred 75% of the daily generated solid wastes to a new constructed sanitary lanfill. The site receives a daily average of 1910 tons. The landfilling is performed by trench method in the form of cells. The produced leachate is discharged into two lined aerated lagoons. The biogas formed from biodegradation of landfilled solid wastes is burned and the produced heat is used for drying the lagoons leachate. The remaining residues are relandfilled. The study aims at assessment of the solid waste sanitary landfill leachate characterization and its impacts on the groundwater. The analysis of the collected data confirms that leachates from the landfill are severely contaminated with organics, salts, and heavy metals. The fluctuations in concentration levels of the different parameters were attributed to aging and thickness of waste layers, stage of decomposition, and re-landfilling of the concentrated residues from the drying lagoons. The concentrations of NH4-N (600 mg/l) indicated that the process of stabilization was still in the initial stages and attributed to the compaction process. The high BOD5 results (28,833 mg/l) indicated that the process of stabilization was in the initial stages which were very slow. The high COD results (45,240 mg/l) can be attributed to the compaction of the wastes which also retards the degradation of the solid wastes. The BOD and COD values indicated clearly severe contamination. The BOD5/COD ratio measured in the current study (0.64) indicated that the leachate of the present study was biodegradable and unstabilized, and required time and favourable conditions for anaerobic biodegradation. Heavy metals were lower compared with what have been observed in other countries. Re-landfilling of the residue after drying the leachate in lagoons and the short time of biodegradation in the landfill site were factors which effected the high strength of most of the parameters concentrations of the leachate. Assessment of groundwater contamination through piezometer wells around the active cells indicated that there was no contamination from the leachate to the groundwater surrounding the site. The study recommended emphasizing the importance of adjusting the biodegradation factors, the monitoring program, the prohibition of disposing heavy metals, determination of the leachate generation rate, and treatment of leachate.

COMPARISON OF MICROBIAL POPULATIONS IN A CONVENTIONAL AND BIOREACTING MUNICIPAL SOLID WASTE LANDFILLS

EPA Science Inventory

Landfills are the ultimate reactors for biodegradation as they contain nutrients, bacteria, and various redox conditions which, then, change over time. Enhancement of the landill environment to optimize the rates of biodegradation and to ensure more rapid stabilization of the was...

An equivalent-time-lines model for municipal solid waste based on its compression characteristics.

PubMed

Gao, Wu; Bian, Xuecheng; Xu, Wenjie; Chen, Yunmin

2017-10-01

Municipal solid waste (MSW) demonstrates a noticeable time-dependent stress-strain behavior, which contributes greatly to the settlement of landfills and therefore influences both the storage capacity of landfills and the integrity of internal structures. The long-term compression tests for MSW under different biodegradation conditions were analyzed. It showed that the primary compression can affect the secondary compression due to the biodegradation and mechanical creep. Based on the time-lines model for clays and the compression characteristics of MSW, relationships between MSW's viscous strain rate and equivalent time were established, and then the viscous strain functions of MSW under different biodegradation conditions were deduced, and an equivalent-time-lines model for MSW settlement for two biodegradation conditions was developed, including the Type I model for the enhanced biodegradation condition and the Type II model for the normal biodegradation condition. The simulated compression results of laboratory and field compression tests under different biodegradation conditions were consistent with the measured data, which showed the reliability of both types of the equivalent-time-lines model for MSW. In addition, investigations of the long-term settlement of landfills from the literature indicated that the Type I model is suitable for predicting settlement in MSW landfills with a distinct biodegradation progress of MSW, a high content of organics in MSW, a short fill age or under an enhanced biodegradation environment; while the Type II model is good at predicting settlement in MSW landfills with a distinct progress of mechanical creep compression, a low content of organics in MSW, a long fill age or under a normal biodegradation condition. Furthermore, relationships between model parameters and the fill age of landfills were summarized. Finally, the similarities and differences between the equivalent-time-lines model for MSW and the stress-biodegradation model for MSW were discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aloe vera in active and passive regions of electronic devices towards a sustainable development

NASA Astrophysics Data System (ADS)

Lim, Zhe Xi; Sreenivasan, Sasidharan; Wong, Yew Hoong; Cheong, Kuan Yew

2017-07-01

The increasing awareness towards sustainable development of electronics has driven the search for natural bio-organic materials in place of conventional electronic materials. The concept of using natural bio-organic materials in electronics provides not only an effective solution to address global electronic waste crisis, but also a compelling template for sustainable electronics manufacturing. This paper attempts to provide an overview of using Aloe vera gel as a natural bio-organic material for various electronic applications. Important concepts such as responses of living Aloe vera plant towards electrical stimuli and demonstrations of Aloe vera films as passive and active regions of electronic devices are highlighted in chronological order. The biodegradability and biocompatibility of Aloe vera can bring the world a step closer towards the ultimate goal of sustainable development of electronic devices from "all-natural" materials.

Biodegradable Materials for Bone Repair and Tissue Engineering Applications

PubMed Central

Sheikh, Zeeshan; Najeeb, Shariq; Khurshid, Zohaib; Verma, Vivek; Rashid, Haroon; Glogauer, Michael

2015-01-01

This review discusses and summarizes the recent developments and advances in the use of biodegradable materials for bone repair purposes. The choice between using degradable and non-degradable devices for orthopedic and maxillofacial applications must be carefully weighed. Traditional biodegradable devices for osteosynthesis have been successful in low or mild load bearing applications. However, continuing research and recent developments in the field of material science has resulted in development of biomaterials with improved strength and mechanical properties. For this purpose, biodegradable materials, including polymers, ceramics and magnesium alloys have attracted much attention for osteologic repair and applications. The next generation of biodegradable materials would benefit from recent knowledge gained regarding cell material interactions, with better control of interfacing between the material and the surrounding bone tissue. The next generations of biodegradable materials for bone repair and regeneration applications require better control of interfacing between the material and the surrounding bone tissue. Also, the mechanical properties and degradation/resorption profiles of these materials require further improvement to broaden their use and achieve better clinical results. PMID:28793533

Improving the engineering properties of PLA for 3D printing and beyond

NASA Astrophysics Data System (ADS)

Rocha Gutierrez, Carmen Raquel

Additive manufacturing (AM), now more commonly known as 3D printing, has been classified as efficient, fast, and practical in the prototyping sector of product development. In the work presented here, we will use one of the AM techniques known as Material extrusion 3D printing (ME3DP), which has all the advantages of AM. However, one of the biggest challenges facing ME3DP technologies is the limitation of the range of materials used by this technique. Acrylonitrile butadiene styrene (ABS) and poly-lactic acid (PLA) are currently the most common thermoplastics materials used in ME3DP because of their ability to melt and be reprocessed. PLA is a biodegradable polymer derived from renewable sources such as corn, and sugarcane. The expanded use of this polymer over traditional petroleum-based plastics (ABS) will decrease the demand on petrochemicals, and also lead to less non-biodegradable polymeric waste. While PLA offers an eco-friendly solution for polymeric 3D printing, the mechanical performance is limited by PLA's inherent characteristics (such as moisture absorbance) that may degrade the plastic during processing. PLA novel systems were used through this research maintaining the compatibility with material extrusion 3D printers. The purpose of this investigation is to alter the physical properties of PLA with sustainable additives in order to improve the end use products from this material.

Integrated systems for biopolymers and bioenergy production from organic waste and by-products: a review of microbial processes.

PubMed

Pagliano, Giorgia; Ventorino, Valeria; Panico, Antonio; Pepe, Olimpia

2017-01-01

Recently, issues concerning the sustainable and harmless disposal of organic solid waste have generated interest in microbial biotechnologies aimed at converting waste materials into bioenergy and biomaterials, thus contributing to a reduction in economic dependence on fossil fuels. To valorize biomass, waste materials derived from agriculture, food processing factories, and municipal organic waste can be used to produce biopolymers, such as biohydrogen and biogas, through different microbial processes. In fact, different bacterial strains can synthesize biopolymers to convert waste materials into valuable intracellular (e.g., polyhydroxyalkanoates) and extracellular (e.g., exopolysaccharides) bioproducts, which are useful for biochemical production. In particular, large numbers of bacteria, including Alcaligenes eutrophus , Alcaligenes latus , Azotobacter vinelandii , Azotobacter chroococcum , Azotobacter beijerincki , methylotrophs, Pseudomonas spp., Bacillus spp., Rhizobium spp., Nocardia spp., and recombinant Escherichia coli , have been successfully used to produce polyhydroxyalkanoates on an industrial scale from different types of organic by-products. Therefore, the development of high-performance microbial strains and the use of by-products and waste as substrates could reasonably make the production costs of biodegradable polymers comparable to those required by petrochemical-derived plastics and promote their use. Many studies have reported use of the same organic substrates as alternative energy sources to produce biogas and biohydrogen through anaerobic digestion as well as dark and photofermentation processes under anaerobic conditions. Therefore, concurrently obtaining bioenergy and biopolymers at a reasonable cost through an integrated system is becoming feasible using by-products and waste as organic carbon sources. An overview of the suitable substrates and microbial strains used in low-cost polyhydroxyalkanoates for biohydrogen and biogas production is given. The possibility of creating a unique integrated system is discussed because it represents a new approach for simultaneously producing energy and biopolymers for the plastic industry using by-products and waste as organic carbon sources.

A process for complete biodegradation of shrimp waste by a novel marine isolate Paenibacillus sp. AD with simultaneous production of chitinase and chitin oligosaccharides.

PubMed

Kumar, Aditya; Kumar, Deepak; George, Nancy; Sharma, Prince; Gupta, Naveen

2018-04-01

Disposal of chitinaceous waste is a major problem of seafood industry. Most of the known chitinolytic organisms have been studied with respect to pure chitin as substrate. Use of these organisms for degradation of seafood waste has not been explored much. In present study a marine bacterium capable of proficiently degrading shrimp waste with co-production of value added products like chitinase and chitin oligosaccharides was isolated from seafood waste dumping sites. On 16s rRNA and biochemical analysis bacterium was found to be a novel species of genus Paenibacillus.Under optimized condition complete shrimp waste degradation (99%) was achieved along with chitinase yield of 20.01 IUml -1 . SEM and FTIR showed the structural changes and breakage of bonds typical to that of chitin, which indicated that this process can be used for the degradation of other chitinaceous material also. Thin layer chromatography revealed the presence of chitin oligosaccharides of various degree of polymerization in the hydrolysate. Complete degradation of shrimp waste by Paenibacillus sp. AD makes it a potential candidate for the bioremediation of seafood waste at large scale. Concomitant production of chitinase and chitin oligosaccharides further makes the process economical and commercially viable. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparative evaluation of anaerobic digestion for sewage sludge and various organic wastes with simple modeling.

PubMed

Hidaka, Taira; Wang, Feng; Tsumori, Jun

2015-09-01

Anaerobic co-digestion of sewage sludge and other organic wastes, such as kitchen garbage, food waste, and agricultural waste, at a wastewater treatment plant (WWTP) is a promising method for both energy and material recovery. Substrate characteristics and the anaerobic digestion performance of sewage sludge and various organic wastes were compared using experiments and modeling. Co-digestion improved the value of digested sewage sludge as a fertilizer. The relationship between total and soluble elemental concentrations was correlated with the periodic table: most Na and K (alkali metals) were soluble, and around 20-40% of Mg and around 10-20% of Ca (alkaline earth metals) were soluble. The ratio of biodegradable chemical oxygen demand of organic wastes was 65-90%. The methane conversion ratio and methane production rate under mesophilic conditions were evaluated using a simplified mathematical model. There was reasonably close agreement between the model simulations and the experimental results in terms of methane production and nitrogen concentration. These results provide valuable information and indicate that the model can be used as a pre-evaluation tool to facilitate the introduction of co-digestion at WWTPs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impact of initial biodegradability on sludge anaerobic digestion enhancement by thermal pretreatment.

PubMed

Carrère, Hélène; Bougrier, Claire; Castets, Delphine; Delgenès, Jean Philippe

2008-11-01

Thermal treatments with temperature ranging from 60 to 210 degrees C were applied to 6 waste-activated sludge samples originating from high or medium load, extended aeration wastewater treatment processes that treated different wastewaters (urban, urban and industrial or slaughterhouse). COD sludge solubilisation was linearly correlated with the treatment temperature on the whole temperature range and independently of the sludge samples. Sludge batch mesophilic biodegradability increased with treatment temperature up to 190 degrees C. In this temperature range, biodegradability enhancement or methane production increase by thermal hydrolysis was shown to be a function of sludge COD solubilisation but also of sludge initial biodegradability. The lower the initial biodegradability means the higher efficiency of thermal treatment.

Improved biogas production and biodegradation of oilseed rape straw by using kitchen waste and duck droppings as co-substrates in two-phase anaerobic digestion

PubMed Central

Wang, Chuqiao; Hong, Feng; Lu, Yong; Liu, Hengming

2017-01-01

Oilseed rape straw (ORS) is a kind of biorefractory waste widely existing in the rural area of China, which is highly suitable to mix with kitchen waste (KW) and duck droppings (DD) in two-phase anaerobic digestion (AD). This research introduced the importance of KW and DD addition to improve the biogas production and biodegradation of ORS. A set of comparative experiments were conducted on two-phase mono- and co-digestion with organic load of 60 g VS/L. The total methane yield (TMY) and the biodegradation of ORS of co-digestions were obviously improving, and the synergistic effect found in the two-phase co-digestions. The optimum mixing ratio of ORS, KW and DD was 50:40:10, and the corresponding TMY and VS degradation rate of ORS were 374.5 mL/g VS and 49.7%, respectively. Addition of KW and DD maintained the pH within the optimal range for the hydrolyzing-acidification, improved the phase separation and buffering capacity of AD system. PMID:28767709

Anaerobic digestion of municipal solid wastes containing variable proportions of waste types.

PubMed

Akunna, J C; Abdullahi, Y A; Stewart, N A

2007-01-01

In many parts of the world there are significant seasonal variations in the production of the main organic wastes, food and green wastes. These waste types display significant differences in their biodegradation rates. This study investigated the options for ensuring process stability during the start up and operation of thermophilic high-solids anaerobic digestion of feedstock composed of varying proportions of food and green wastes. The results show that high seed sludge to feedstock ratio (or low waste loading rate) is necessary for ensuring process pH stability without chemical addition. It was also found that the proportion of green wastes in the feedstock can be used to regulate process pH, particularly when operating at high waste loading rates (or low seed sludge to feedstock ratios). The need for chemical pH correction during start-up and digestion operation decreased with increase in green wastes content of the feedstock. Food wastes were found to be more readily biodegradable leading to higher solids reduction while green wastes brought about pH stability and higher digestate solid content. Combining both waste types in various proportions brought about feedstock with varying buffering capacity and digestion performance. Thus, careful selection of feedstock composition can minimise the need for chemical pH regulation as well as reducing the cost for digestate dewatering for final disposal.

System for Odorless Disposal of Human Waste

NASA Technical Reports Server (NTRS)

Jennings, Dave; Lewis, Tod

1987-01-01

Conceptual system provides clean, hygienic storage. Disposal system stores human wastes compactly. Releases no odor or bacteria and requires no dangerous chemicals or unpleasant handling. Stabilizes waste by natural process of biodegradation in which microbial activity eventually ceases and ordors and bacteria reduced to easily contained levels. Simple and reliable and needs little maintenance.

Towards reinforcement solutions for urban fibre/fabric waste using bio-based biodegradable resins.

NASA Astrophysics Data System (ADS)

Agrawal, Pramod; Hermes, Alina; Bapeer, Solaf; Luiken, Anton; Bouwhuis, Gerrit; Brinks, Ger

2017-10-01

The main research question is how to systematically define and characterize urban textile waste and how to effectively utilise it to produce reinforcement(s) with selected bio-based biodegradable resin(s). Several composite samples have been produced utilising predominantly natural and predominantly synthetic fibres by combining loose fibres with PLA, nonwoven fabric with PLA, woven fabric with PLA, two-layer composite & four-layer composite samples. Physio-chemical characterisations according to the established standards have been conducted. The present work is a step toward the circular economy and closing the loop in textile value chain.

Effects of substrate to inoculum ratio on the biochemical methane potential of piggery slaughterhouse wastes.

PubMed

Yoon, Young-Man; Kim, Seung-Hwan; Shin, Kook-Sik; Kim, Chang-Hyun

2014-04-01

The aim of this study was to assess the effect of substrate to inoculum ratio (S/I ratio) on the biochemical methane potential (BMP) and anaerobic biodegradability (Ddeg) of different piggery slaughterhouse wastes, such as piggery blood, intestine residue, and digestive tract content. These wastes were sampled from a piggery slaughterhouse located in Kimje, South Korea. Cumulative methane production curves for the wastes were obtained from the anaerobic batch fermentation having different S/I ratios of 0.1, 0.5, 1.0, and 1.5. BMP and anaerobic biodegradabilities (Ddeg) of the wastes were calculated from cumulative methane production data for the tested conditions. At the lowest S/I ration of 0.1, BMPs of piggery blood, intestine residue, and digestive tract content were determined to be 0.799, 0.848, and 1.076 Nm(3) kg(-1)-VSadded, respectively, which were above the theoretical methane potentials of 0.539, 0.644, and 0.517 Nm(3) kg(-1)-VSadded for blood, intestine residue, and digestive tract content, respectively. However, BMPs obtained from the higher S/I ratios of 0.5, 1.0, and 1.5 were within the theoretical range for all three types of waste and were not significantly different for the different S/I ratios tested. Anaerobic biodegradabilities calculated from BMP data showed a similar tendency. These results imply that, for BMP assay in an anaerobic reactor, the S/I ratio of anaerobic reactor should be above 0.1 and the inoculum should be sufficiently stabilized to avoid further degradation during the assay.

Effects of Substrate to Inoculum Ratio on the Biochemical Methane Potential of Piggery Slaughterhouse Wastes

PubMed Central

Yoon, Young-Man; Kim, Seung-Hwan; Shin, Kook-Sik; Kim, Chang-Hyun

2014-01-01

The aim of this study was to assess the effect of substrate to inoculum ratio (S/I ratio) on the biochemical methane potential (BMP) and anaerobic biodegradability (Ddeg) of different piggery slaughterhouse wastes, such as piggery blood, intestine residue, and digestive tract content. These wastes were sampled from a piggery slaughterhouse located in Kimje, South Korea. Cumulative methane production curves for the wastes were obtained from the anaerobic batch fermentation having different S/I ratios of 0.1, 0.5, 1.0, and 1.5. BMP and anaerobic biodegradabilities (Ddeg) of the wastes were calculated from cumulative methane production data for the tested conditions. At the lowest S/I ration of 0.1, BMPs of piggery blood, intestine residue, and digestive tract content were determined to be 0.799, 0.848, and 1.076 Nm3 kg−1-VSadded, respectively, which were above the theoretical methane potentials of 0.539, 0.644, and 0.517 Nm3 kg−1-VSadded for blood, intestine residue, and digestive tract content, respectively. However, BMPs obtained from the higher S/I ratios of 0.5, 1.0, and 1.5 were within the theoretical range for all three types of waste and were not significantly different for the different S/I ratios tested. Anaerobic biodegradabilities calculated from BMP data showed a similar tendency. These results imply that, for BMP assay in an anaerobic reactor, the S/I ratio of anaerobic reactor should be above 0.1 and the inoculum should be sufficiently stabilized to avoid further degradation during the assay. PMID:25049994

Microbial characterization and hydrocarbon biodegradation potential of natural bilge waste microflora.

PubMed

Olivera, N L; Commendatore, M G; Delgado, O; Esteves, J L

2003-09-01

Shipping operations produce oily wastes that must be managed properly to avoid environmental pollution. The aim of this study was to characterize microorganisms occurring in ship bilge wastes placed in open lagoons and, particularly, to assess their potential to degrade polycyclic aromatic hydrocarbons (PAHs). A first-order kinetic was suitable for describing hydrocarbon biodegradation after 17 days of treatment. The calculated rate constants were 0.0668 and 0.0513 day(-1) with a corresponding half-life of 10.3 and 13.5 days for the aliphatic and aromatic hydrocarbon fractions, respectively. At day 17, PAH removal percentages were: acenaphtylene 100, fluorene 95.2, phenanthrene 93.6, anthracene 70.3, and pyrene 71.5. Methyl phenanthrene removals were lower than that of their parent compound (3-methyl phenanthrene 83.6, 2-methyl phenanthrene 80.8, 1-methyl phenanthrene 77.3, 9-methyl phenanthrene 75.1, and 2,7-dimethyl phenanthrene 76.6). Neither pure cultures nor the microbial community from these wastes showed extracellular biosurfactant production suggesting that the addition of an exogenously produced biosurfactant may be important in enhancing hydrocarbon bioavailability and biodegradation. DNA analysis of bilge waste samples revealed a ubiquitous distribution of the nahAc genotype in the dump pools. Although almost all of the isolates grew on naphthalene as sole carbon source, only some of them yielded nahAc amplification under the experimental conditions used. The variety of PAHs in bilge wastes could support bacteria with multiple degradation pathways and a diversity of catabolic genes divergent from the classical nah-like type.

Macrofouling communities and the degradation of plastic bags in the sea: an in situ experiment.

PubMed

Pauli, Nora-Charlotte; Petermann, Jana S; Lott, Christian; Weber, Miriam

2017-10-01

The increasing amount of plastic littered into the sea may provide a new substratum for benthic organisms. These marine fouling communities on plastic have not received much scientific attention. We present, to our knowledge, the first comprehensive analysis of their macroscopic community composition, their primary production and the polymer degradation comparing conventional polyethylene (PE) and a biodegradable starch-based plastic blend in coastal benthic and pelagic habitats in the Mediterranean Sea. The biomass of the fouling layer increased significantly over time and all samples became heavy enough to sink to the seafloor. The fouling communities, consisting of 21 families, were distinct between habitats, but not between polymer types. Positive primary production was measured in the pelagic, but not in the benthic habitat, suggesting that large accumulations of floating plastic could pose a source of oxygen for local ecosystems, as well as a carbon sink. Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies.

Modeling microbiological and chemical processes in municipal solid waste bioreactor, Part II: Application of numerical model BIOKEMOD-3P.

PubMed

Gawande, Nitin A; Reinhart, Debra R; Yeh, Gour-Tsyh

2010-02-01

Biodegradation process modeling of municipal solid waste (MSW) bioreactor landfills requires the knowledge of various process reactions and corresponding kinetic parameters. Mechanistic models available to date are able to simulate biodegradation processes with the help of pre-defined species and reactions. Some of these models consider the effect of critical parameters such as moisture content, pH, and temperature. Biomass concentration is a vital parameter for any biomass growth model and often not compared with field and laboratory results. A more complex biodegradation model includes a large number of chemical and microbiological species. Increasing the number of species and user defined process reactions in the simulation requires a robust numerical tool. A generalized microbiological and chemical model, BIOKEMOD-3P, was developed to simulate biodegradation processes in three-phases (Gawande et al. 2009). This paper presents the application of this model to simulate laboratory-scale MSW bioreactors under anaerobic conditions. BIOKEMOD-3P was able to closely simulate the experimental data. The results from this study may help in application of this model to full-scale landfill operation.

The enhancement of anaerobic biodegradability of waste activated sludge by surfactant mediated biological pretreatment.

PubMed

Kavitha, S; Jayashree, C; Adish Kumar, S; Yeom, Ick Tae; Rajesh Banu, J

2014-09-01

In this study, the role of sodium dodecyl sulfate (SDS) was explored for the removal of extracellular polymeric substance (EPS) from waste activated sludge (WAS) followed by enzymatic bacterial pretreatment, which enhanced the subsequent anaerobic biodegradability. EPS was removed with 0.02 g/g SS of SDS. In the results of pretreatment, the suspended solids reduction and chemical oxygen demand solubilization were found to be 25.7% and 19.79% for deflocculated and bacterially pretreated sludge, whereas they were found to be 15.7% and 11% for flocculated sludge (without EPS removal and bacterially pretreated) and 7.85% and 6% for control sludge (raw sludge), respectively. Upon examining the anaerobic biodegradability, the biogas yield potential of deflocculated and bacterially pretreated, flocculated, deflocculated alone, and control sludges were found to be 0.467 L/(g VS), 0.355 L/(g VS), 0.315 L/(g VS), and 0.212 L/(g VS), respectively. Thus, the deflocculation and bacterial pretreatment improved the anaerobic biodegradability efficiently. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial activity of biodegradable polysaccharide and protein-based films containing active agents.

PubMed

Kuorwel, Kuorwel K; Cran, Marlene J; Sonneveld, Kees; Miltz, Joseph; Bigger, Stephen W

2011-04-01

Significant interest has emerged in the introduction of food packaging materials manufactured from biodegradable polymers that have the potential to reduce the environmental impacts associated with conventional packaging materials. Current technologies in active packaging enable effective antimicrobial (AM) packaging films to be prepared from biodegradable materials that have been modified and/or blended with different compatible materials and/or plasticisers. A wide range of AM films prepared from modified biodegradable materials have the potential to be used for packaging of various food products. This review examines biodegradable polymers derived from polysaccharides and protein-based materials for their potential use in packaging systems designed for the protection of food products from microbial contamination. A comprehensive table that systematically analyses and categorizes much of the current literature in this area is included in the review.

Perspectives on the production, structural characteristics and potential applications of bioplastics derived from polyhydroxyalkanoates.

PubMed

Albuquerque, Priscilla B S; Malafaia, Carolina B

2018-02-01

Since the last two decades, the use of synthetic materials has increased and become more frequent in this capitalist system. Polymers used as raw materials are usually disposed very rapidly and considered serious damages when they return to the environment. Because of this behaviour, there was an increasing in the global awareness by minimizing the waste generated, in addition to the scientific community concern for technological alternatives to solve this problem. Alternatively, biodegradable polymers are attracting special interest due to their inherent properties, which are similar to the ones of the conventional plastics. Bioplastics covers plastics made from renewable resources, including plastics that biodegrade under controlled conditions at the end of their use phase. Polyhydroxyalkanoates (PHAs) are polyesters composed of hydroxy acids, synthesized by a variety of microorganisms as intracellular carbon and energy storage. These environmentally friendly biopolymers have excellent potential in domestic, agricultural, industrial and medical field, however their production on a large scale is still limited. This review considered the most recent scientific publications on the production of bioplastics based on PHAs, their structural characteristics and the exploitation of different renewable sources of raw materials. In addition, there were also considered the main biotechnological applications of these biopolymers. Copyright © 2017 Elsevier B.V. All rights reserved.

Improving the amenability of municipal waste activated sludge for biological pretreatment by phase-separated sludge disintegration method.

PubMed

Kavitha, S; Adish Kumar, S; Kaliappan, S; Yeom, Ick Tae; Rajesh Banu, J

2014-10-01

The significance of citric acid, a cation binding agent, was investigated for the exclusion of extracellular polymeric substance (EPS) from waste activated sludge (WAS) and anaerobic biodegradability following enzymatic bacterial pretreatment. EPS was removed with 0.05 g/g SS of citric acid. The results of pretreatment found that the suspended solids reduction and chemical oxygen demand solubilisation were 21.4% and 16.2% for deflocculated-bacterially pretreated sludge, 14.28% and 10.0% for flocculated sludge (without EPS removal and bacterially pretreated) and 8.5% and 6.5% for control sludge (raw sludge), respectively. Further assessing anaerobic biodegradability, the biogas yield potential of deflocculated and bacterially pretreated, flocculated, and control sludges were found to be 0.455 L/(g VS), 0.343 L/(g VS), and 0.209 L/(g VS), respectively. Thus, phase-separated disintegration enhanced anaerobic biodegradability efficiently. Copyright © 2014 Elsevier Ltd. All rights reserved.

Genetic and chemical analyzes of transformations in compost compounds during biodegradation of oiled bleaching earth with waste sludge.

PubMed

Piotrowska-Cyplik, Agnieszka; Cyplik, Paweł; Marecik, Roman; Czarny, Jakub; Szymański, Andrzej; Wyrwas, Bogdan; Framski, Grzegorz; Chrzanowski, Lukasz; Materna, Katarzyna

2012-06-01

Composting of oiled bleaching earth with waste sludge and corn straw was carried out to investigate the ability of microorganisms to synthesize biosurfactants that might decrease the surface tension of composts. Analytical results and changes in the surface tension suggest that biodegradation of fatty by-products was the consequence of emulsifying properties of higher fatty acids. The surface tension for isolates from all composting phases was between 37 and 43 mN m(-1). No substances synthesized by microorganisms that might be able to decrease the surface tension were detected in composts. Tensammetric, TLC and HPLC-MS results and changes in surface tension suggest that biodegradation of fatty by-products results from the emulsifying properties of higher fatty acids. A decrease in fatty content from 144 to 6 mg g(-1) dry matter was obtained. Copyright © 2012 Elsevier Ltd. All rights reserved.

Co-composting of eggshell waste in self-heating reactors: monitoring and end product quality.

PubMed

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.

Natural bioactive compounds from winery by-products as health promoters: a review.

PubMed

Teixeira, Ana; Baenas, Nieves; Dominguez-Perles, Raul; Barros, Ana; Rosa, Eduardo; Moreno, Diego A; Garcia-Viguera, Cristina

2014-09-04

The relevance of food composition for human health has increased consumers' interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health.

Optimized Production of Biodiesel from Waste Cooking Oil by Lipase Immobilized on Magnetic Nanoparticles

PubMed Central

Yu, Chi-Yang; Huang, Liang-Yu; Kuan, I-Ching; Lee, Shiow-Ling

2013-01-01

Biodiesel, a non-toxic and biodegradable fuel, has recently become a major source of renewable alternative fuels. Utilization of lipase as a biocatalyst to produce biodiesel has advantages over common alkaline catalysts such as mild reaction conditions, easy product separation, and use of waste cooking oil as raw material. In this study, Pseudomonas cepacia lipase immobilized onto magnetic nanoparticles (MNP) was used for biodiesel production from waste cooking oil. The optimal dosage of lipase-bound MNP was 40% (w/w of oil) and there was little difference between stepwise addition of methanol at 12 h- and 24 h-intervals. Reaction temperature, substrate molar ratio (methanol/oil), and water content (w/w of oil) were optimized using response surface methodology (RSM). The optimal reaction conditions were 44.2 °C, substrate molar ratio of 5.2, and water content of 12.5%. The predicted and experimental molar conversions of fatty acid methyl esters (FAME) were 80% and 79%, respectively. PMID:24336109

Porous Biodegradable Metals for Hard Tissue Scaffolds: A Review

PubMed Central

Yusop, A. H.; Bakir, A. A.; Shaharom, N. A.; Abdul Kadir, M. R.; Hermawan, H.

2012-01-01

Scaffolds have been utilized in tissue regeneration to facilitate the formation and maturation of new tissues or organs where a balance between temporary mechanical support and mass transport (degradation and cell growth) is ideally achieved. Polymers have been widely chosen as tissue scaffolding material having a good combination of biodegradability, biocompatibility, and porous structure. Metals that can degrade in physiological environment, namely, biodegradable metals, are proposed as potential materials for hard tissue scaffolding where biodegradable polymers are often considered as having poor mechanical properties. Biodegradable metal scaffolds have showed interesting mechanical property that was close to that of human bone with tailored degradation behaviour. The current promising fabrication technique for making scaffolds, such as computation-aided solid free-form method, can be easily applied to metals. With further optimization in topologically ordered porosity design exploiting material property and fabrication technique, porous biodegradable metals could be the potential materials for making hard tissue scaffolds. PMID:22919393

Use of waste cellophane in the control of sediment : Final report.

DOT National Transportation Integrated Search

1978-01-01

Based on laboratory flume tests, it was concluded that waste cellophane could be used effectively for trapping and filtering waterborne sediment. It was also priced competitively and, like straw and burlap, it was found to be biodegradable in a soil ...

Mechanical Behavior Optimization of Chitosan Extracted from Shrimp Shells as a Sustainable Material for Shopping Bags.

PubMed

D'Angelo, Giacomo; Elhussieny, Amal; Faisal, Marwa; Fahim, I S; Everitt, Nicola M

2018-05-22

The use of biodegradable materials for shopping bag production, and other products made from plastics, has recently been an object of intense research-with the aim of reducing the environmental burdens given by conventional materials. Chitosan is a potential material because of its biocompatibility, degradability, and non-toxicity. It is a semi-natural biopolymeric material produced by the deacetylation of chitin, which is the second most abundant natural biopolymer (after cellulose). Chitin is found in the exoskeleton of insects, marine crustaceans, and the cell walls of certain fungi and algae. The raw materials most abundantly available are the shells of crab, shrimp, and prawn. Hence, in this study chitosan was selected as one of the main components of biodegradable materials used for shopping bag production. Firstly, chitin was extracted from shrimp shell waste and then converted to chitosan. The chitosan was next ground to a powder. Although, currently, polyethylene bags are prepared by blown extrusion, in this preliminary research the chitosan powder was dissolved in a solvent and the films were cast. Composite films with several fillers were used as a reinforcement at different dosages to optimize mechanical properties, which have been assessed using tensile tests. These results were compared with those of conventional polyethylene bags used in Egypt. Overall, the chitosan films were found to have a lower ductility but appeared to be strong enough to fulfill shopping bag functions. The addition of fillers, such as chitin whiskers and rice straw, enhanced the mechanical properties of chitosan films, while the addition of chitin worsened overall mechanical behavior.

Heavy Metals in Water Percolating Through Soil Fertilized with Biodegradable Waste Materials.

PubMed

Wierzbowska, Jadwiga; Sienkiewicz, Stanisław; Krzebietke, Sławomir; Bowszys, Teresa

The influence of manure and composts on the leaching of heavy metals from soil was evaluated in a model lysimeter experiment under controlled conditions. Soil samples were collected from experimental fields, from 0- to 90-cm layers retaining the layout of the soil profile layers, after the second crop rotation cycle with the following plant species: potatoes, spring barley, winter rapeseed, and winter wheat. During the field experiment, 20 t DM/ha of manure, municipal sewage sludge composted with straw (SSCS), composted sewage sludge (SSC), dried granular sewage sludge (DGSS), "Dano" compost made from non-segregated municipal waste (CMMW), and compost made from municipal green waste (CUGW) was applied, i.e., 10 t DM/ha per crop rotation cycle. The concentrations (μg/dm 3 ) of heavy metals in the leachate were as follows: Cd (3.6-11.5) < Mn (4.8-15.4) < Cu (13.4-35.5) < Zn (27.5-48.0) < Cr (36.7-96.5) < Ni (24.4-165.8) < Pb (113.8-187.7). Soil fertilization with organic waste materials did not contaminate the percolating water with manganese or zinc, whereas the concentrations of the other metals increased to the levels characteristic of unsatisfactory water quality and poor water quality classes. The copper and nickel content of percolating water depended on the concentration of those metals introduced into the soil with organic waste materials. The concentrations of Cd in the leachate increased, whereas the concentrations of Cu and Ni decreased with increasing organic C content of organic fertilizers. The widening of the C/N ratio contributed to Mn leaching. The concentrations of Pb, Cr, and Mn in the percolating water were positively correlated with the organic C content of soil.

Research on the use of particles coming from almond husk as fillers for vinyl plastisols to manufacture hollow pieces with similar surface finishing than wood by using a rotational moulding process

NASA Astrophysics Data System (ADS)

Crespo Amoros, Jose Enrique

PVC pastes or plasticized PVC offer great possibilities in the industrial field in which this research work has been developed since they show great relevance in plastic processing. On one hand, it is important to study these materials from different points of view: quality improvement, wide range of performance, high versatility, low costs,.... On the other hand, most of the industrial fields that usually employ these polymeric materials are characterized by developing products on which aesthetic considerations and surface finishing acquire special relevance. These industrial fields include all those on which new designs require complex shapes and new and novelty surface finishing such as interior design (furniture, wood products,...) toys industry, houseware, shoe industry,.... The main aim of this work is to improve the use of PVC plastisols in these industrial fields by optimizing formulations with new additives (low toxicity plasticizers) and fillers (lignocellulosic wastes) to obtain new materials that minimize damages to environment. In this work, we have developed new plastisol formulations based on the use of low toxicity plasticizers to obtain more ecological plastisols. We have used a biodegradable plasticizer DINCH which is a derivative of a dicarboxilate as substitute of traditional plasticizers based on phthalates. As we are working with relatively new plasticizers (specially at industrial level) we have performed a whole study of its properties by using different experimental analysis techniques such as differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamical-mechanical analysis (DMA) and espectrofotometric techniques (visible and infrared). Furthermore a complete mechanical characterization has been carried out to analyze the most important parameters that influence on materials properties such as processing parameters (temperature and time) and plastisol formulations (mainly plasticizer content). We have also performed a comparative study regarding the results obtained with the most used plasticizer at industrial level, di-octyl phthalate (DOP). After this characterization, a study on the addition of cellulosic fillers was carried out to obtain materials with similar surface finishing than wood products. We used three different lignocellulosic fillers coming from wastes: almond husk residues since these wastes are quite abundant in our influence zone, rice husk and sawdust residues since they are produced everywhere in high amounts. It was studied the influence of the morphology and particle size on the final properties of the prepared mixtures to optimize formulations. These new plastisol formulations allow obtaining new materials in a wide range of mechanical properties, easy processing, interesting surface finishing and partially biodegradable, more careful with environment.

Study of thermal pre-treatment on anaerobic digestion of slaughterhouse waste by TGA-MS and FTIR spectroscopy.

PubMed

Rodríguez-Abalde, Ángela; Gómez, Xiomar; Blanco, Daniel; Cuetos, María José; Fernández, Belén; Flotats, Xavier

2013-12-01

Thermogravimetric analysis coupled to mass spectrometry (TGA-MS) and Fourier-transform infrared spectroscopy (FTIR) were used to describe the effect of pasteurization as a hygienic pre-treatment of animal by-products over biogas production. Piggery and poultry meat wastes were used as substrates for assessing the anaerobic digestion under batch conditions at mesophilic range. Poultry waste was characterized by high protein and carbohydrate content, while piggery waste presented a major fraction of fat and lower carbohydrate content. Results from anaerobic digestion tests showed a lower methane yield for the pre-treated poultry sample. TGA-MS and FTIR spectroscopy allowed the qualitative identification of recalcitrant nitrogen-containing compounds in the pre-treated poultry sample, produced by Maillard reactions. In the case of piggery waste, the recalcitrant compounds were not detected and its biodegradability test reported higher methane yield and production rates. TGA-MS and FTIR spectroscopy were demonstrated to be useful tools for explaining results obtained by anaerobic biodegradability test and in describing the presence of inhibitory problems.

Modified version of ADM1 model for agro-waste application.

PubMed

Galí, A; Benabdallah, T; Astals, S; Mata-Alvarez, J

2009-06-01

Agro-residues account for a large proportion of the wastes generated around the world. There is thus a need for a model to simulate the anaerobic digestion processes used in their treatment. We have developed model based on ADM1, to be applied to agro-wastes. We examined and tested the biodegradability of apple, pear, orange, rape, sunflower, pig manure and glycerol wastes to be used as the basis for feeding the model. Moreover, the fractions of particulate COD (X(c)) were calculated, and the disintegration constant was obtained from biodegradability profiles, considering disintegration to be the limiting process. The other kinetic and stoichiometric parameters were taken from the ADM1 model. The model operating under mono-substrate and co-substrate conditions was then validated with batch tests. At the same time the model was validated on a continuous anaerobic reactor operating with pig manure at lab scale. In both cases the correlation between the model and the experimental results was satisfactory. We conclude that the anaerobic digestion model is a reliable tool for the design and operation of plants in which agro-wastes are treated.

Use of Fenton reaction for the treatment of leachate from composting of different wastes.

PubMed

Trujillo, Daniel; Font, Xavier; Sánchez, Antoni

2006-11-02

The oxidation of leachate coming from the composting of two organic wastes (wastewater sludge and organic fraction of municipal solid wastes) using the Fenton's reagent was studied using different ratios [Fe(2+)]/[COD](0) and maintaining a ratio [H(2)O(2)]/[COD](0) equal to 1. The optimal conditions for Fenton reaction were found at a ratio [Fe(2+)]/[COD](0) equal to 0.1. Both leachates were significantly oxidized under these conditions in terms of COD removal (77 and 75% for leachate from wastewater sludge composting and leachate from organic fraction of municipal solid wastes, respectively) and BOD(5) removal (90 and 98% for leachate from wastewater sludge composting and leachate from organic fraction of municipal solid wastes, respectively). Fenton's reagent was found to oxidize preferably biodegradable organic matter of leachate. In consequence, a decrease in the biodegradability of leachates was observed after Fenton treatment for both leachates. Nevertheless, Fenton reaction proved to be a feasible technique for the oxidation of the leachate under study, and it can be considered a suitable treatment for this type of wastewaters.

Microbial Bioreactor Development in the ALS NSCORT

NASA Astrophysics Data System (ADS)

Mitchell, Cary; Whitaker, Dawn; Banks, M. Katherine; Heber, Albert J.; Turco, Ronald F.; Nies, Loring F.; Alleman, James E.; Sharvelle, Sybil E.; Li, Congna; Heller, Megan

The NASA Specialized Center of Research and Training in Advanced Life Support (the ALS NSCORT), a partnership of Alabama A & M, Howard, and Purdue Universities, was established by NASA in 2002 to develop technologies that will reduce the Equivalent System Mass (ESM) of regenerative processes within future space life-support systems. A key focus area of NSCORT research has been the development of efficient microbial bioreactors for treatment of human, crop, and food-process wastes while enabling resource recovery. The approach emphasizes optimizing the energy-saving advantages of hydrolytic enzymes for biomass degradation, with focus on treatment of solid wastes including crop residue, paper, food, and human metabolic wastes, treatment of greywater, cabin air, off-gases from other treatment systems, and habitat condensate. This summary includes important findings from those projects, status of technology development, and recommendations for next steps. The Plant-based Anaerobic-Aerobic Bioreactor-Linked Operation (PAABLO) system was developed to reduce crop residue while generating energy and/or food. Plant residues initially were added directly to the bioreactor, and recalcitrant residue was used as a substrate for growing plants or mushrooms. Subsequently, crop residue was first pretreated with fungi to hydrolyze polymers recalcitrant to bacteria, and leachate from the fungal beds was directed to the anaerobic digester. Exoenzymes from the fungi pre-soften fibrous plant materials, improving recovery of materials that are more easily biodegraded to methane that can be used for energy reclamation. An Autothermal Thermophilic Aerobic Digestion (ATAD) system was developed for biodegradable solid wastes. Objectives were to increase water and nutrient recovery, reduce waste volume, and inactivate pathogens. Operational parameters of the reactor were optimized for degradation and resource recovery while minimizing system requirements and footprint. The start-up behavior and recycling of effluent supernatant were evaluated to maximize degradation and minimize water input. The off-gases proceeded to a bioregenerative air-treatment reactor, and the sludge effluent was investigated for multiple downstream uses including dewatering by reed beds, use as a nutrient supplement for fish or mushroom growth, and as a growth medium and nutrient source for various crops. The Bio-Regenerative Environmental Air Treatment for Health (BREATHe I) reactor treated greywater and off-gases from the thermophilic aerobic digestion reactor which contained elevated levels of ammonia (NH3 ) and hydrogen sulfide (H2 S). BREATHe I development focused initially on removing greywater contaminants with clean air supplied to a biotrickling filter. Limited removal of organic carbon (70%) led to studies indicating that biodegradation metabolites of the surfactant disodium cocoamphodiacetate are recalcitrant. Subsequent studies showed that NH3 loaded at 150 mg/min and H2 S at 0.83 mg/min were removed completely, while removal of carbonaceous compounds from greywater remained constant. A BREATHe II reactor emphasized biofilters and biotrickling filters for removal of ersatz multicomponent gaseous waste streams representative of habitat air and atmospheric condensate. The model waste stream contained a mixture of acetone, n-butanol, methane, ethylene, and ammonia. Both biofilters and biotrickling filters packed with different media were able to achieve complete removal of easily soluble compounds such as acetone, n-butanol, and ammonia within a short startup period, whereas methane was not removed because of its extreme aqueous insolubility. Different packing media and bioreactor configurations were subsequently assessed, as well as the effect of influent ammonia concentration. Research sponsored in part by NASA grant NAG5-12686.

Preliminary study to characterize plastic polymers using elemental analyser/isotope ratio mass spectrometry (EA/IRMS).

PubMed

Berto, Daniela; Rampazzo, Federico; Gion, Claudia; Noventa, Seta; Ronchi, Francesca; Traldi, Umberto; Giorgi, Giordano; Cicero, Anna Maria; Giovanardi, Otello

2017-06-01

Plastic waste is a growing global environmental problem, particularly in the marine ecosystems, in consideration of its persistence. The monitoring of the plastic waste has become a global issue, as reported by several surveillance guidelines proposed by Regional Sea Conventions (OSPAR, UNEP) and appointed by the EU Marine Strategy Framework Directive. Policy responses to plastic waste vary at many levels, ranging from beach clean-up to bans on the commercialization of plastic bags and to Regional Plans for waste management and recycling. Moreover, in recent years, the production of plant-derived biodegradable plastic polymers has assumed increasing importance. This study reports the first preliminary characterization of carbon stable isotopes (δ 13 C) of different plastic polymers (petroleum- and plant-derived) in order to increase the dataset of isotopic values as a tool for further investigation in different fields of polymers research as well as in the marine environment surveillance. The δ 13 C values determined in different packaging for food uses reflect the plant origin of "BIO" materials, whereas the recycled plastic materials displayed a δ 13 C signatures between plant- and petroleum-derived polymers source. In a preliminary estimation, the different colours of plastic did not affect the variability of δ 13 C values, whereas the abiotic and biotic degradation processes that occurred in the plastic materials collected on beaches and in seawater, showed less negative δ 13 C values. A preliminary experimental field test confirmed these results. The advantages offered by isotope ratio mass spectrometry with respect to other analytical methods used to characterize the composition of plastic polymers are: high sensitivity, small amount of material required, rapidity of analysis, low cost and no limitation in black/dark samples compared with spectroscopic analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lignin biopolymer based triboelectric nanogenerators

NASA Astrophysics Data System (ADS)

Bao, Yukai; Wang, Ruoxing; Lu, Yunmei; Wu, Wenzhuo

2017-07-01

Ongoing research in triboelectric nanogenerators (TENGs) focuses on increasing power generation, but obstacles concerning economical and eco-friendly utilization of TENGs continue to prevail. Being the second most abundant biopolymer on earth, lignin offers a valuable opportunity for low-cost TENG applications in biomedical devices, benefitting from its biodegradability and biocompatibility. Here, we develop for the first time a lignin biopolymer based TENGs for harvesting mechanical energy in the environment, which shows great potential for self-powered biomedical devices among other applications and opens doors to new technologies that utilize otherwise wasted materials for economically feasible and ecologically friendly production of energy devices.

Leachate recirculation: moisture content assessment by means of a geophysical technique.

PubMed

Guérin, Roger; Munoz, Marie Laure; Aran, Christophe; Laperrelle, Claire; Hidra, Mustapha; Drouart, Eric; Grellier, Solenne

2004-01-01

Bioreactor technology is a waste treatment concept consisting in speeding up the biodegradation of landfilled waste by optimizing its moisture content through leachate recirculation. The measurement of variations in waste moisture content is critical in the design and control of bioreactors. Conventional methods such as direct physical sampling of waste reach their limits due to the interference with the waste matrix. This paper reviews geophysical measurements such as electrical direct current and electromagnetic slingram methods for measuring the electrical conductivity. Electrical conductivity is a property, which is linked to both moisture and temperature and can provide useful indications on the biodegradation environment in the waste mass. The study reviews three site experiments: a first experimentation shows the advantages (correlation between conductive anomaly and water seepage) but also the limits of geophysical interpretation; the two other sites allow the leachate recirculation to be tracked by studying the relative resistivity variation versus time from electrical 2D imaging. Even if some improvements are necessary to consider geophysical measurements as a real bioreactor monitoring tool, results are promising and could lead to the use of electrical 2D imaging in bioreactor designing.

Comparative study on the biodegradability of morpholinium herbicidal ionic liquids.

PubMed

Ławniczak, Łukasz; Materna, Katarzyna; Framski, Grzegorz; Szulc, Alicja; Syguda, Anna

2015-07-01

This study focused on evaluating the toxicity as well as primary and ultimate biodegradability of morpholinium herbicidal ionic liquids (HILs), which incorporated MCPA, MCPP, 2,4-D or Dicamba anions. The studied HILs were also subjected to determination of surface active properties in order to assess their influence on toxicity and biodegradability. The study was carried out with microbiota isolated from different environmental niches: sediments from river channel, garden soil, drainage trench collecting agricultural runoff stream, agricultural soil and municipal waste repository. The obtained results revealed that resistance to toxicity and biodegradation efficiency of the microbiota increased in the following order: microbiota from the waste repository > microbiota from agricultural soil ≈ microbiota from an agricultural runoff stream > microbiota from garden soil > microbiota from the river sludge. It was observed that the toxicity of HILs increased with the hydrophobicity of the cation, however the influence of the anion was more notable. The highest toxicity was observed when MCPA was used as the anion (EC50 values ranging from 60 to 190 mg L(-1)). The results of ultimate biodegradation tests indicated that only HILs with 2,4-D as the anion were mineralized to some extent, with slightly higher values for HILs with the 4-decyl-4-ethylmorpholinium cation (10-31 %) compared to HILs with the 4,4-didecylmorpholinium cation (9-20 %). Overall, the cations were more susceptible (41-94 %) to primary biodegradation compared to anions (0-61 %). The obtained results suggested that the surface active properties of the studied HILs may influence their toxicity and biodegradability by bacteria in different environmental niches.

Electricity generation from food wastes and characteristics of organic matters in microbial fuel cell.

PubMed

Li, Hui; Tian, Yu; Zuo, Wei; Zhang, Jun; Pan, Xiaoyue; Li, Lipin; Su, Xinying

2016-04-01

The microbial fuel cell (MFC) was evaluated as an alternative way to recover electricity from canteen based food waste. Characteristics of the organics in food waste before and after the MFC treatment were analyzed to investigate how the organic matters were biodegraded and transformed during the MFC treatment. A maximum power density of 5.6W/m(3) and an average output voltage of 0.51V were obtained. During the MFC operation, the hydrophilic and acidic fractions were more readily degraded, compared to the neutral fractions. Additionally, aromatic compounds in the hydrophilic fraction were more preferentially removed than non-aromatic compounds. The MFC could easily remove the tryptophan protein-like substances in all fractions and aromatic proteins in hydrophilic and hydrophobic neutral fractions. Additionally, the hydrophobic amide-1 proteins and aliphatic components were readily hydrolyzed and biodegraded in the MFC. These findings may facilitate the pretreatment and posttreatment choices for MFC system fed with food waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis of hydrophilic and hydrophobic carbon quantum dots from waste of wine fermentation

NASA Astrophysics Data System (ADS)

Varisco, Massimo; Zufferey, Denis; Ruggi, Albert; Zhang, Yucheng; Erni, Rolf; Mamula, Olimpia

2017-12-01

Wine lees are one of the main residues formed in vast quantities during the fermentation of wine. While toxic when applied to plants and wetlands, it is a biodegradable material, and several alternatives have been proposed for its valorization as: dietary supplement in animal feed, source for various yeast extracts and bioconversion feedstock. The implementation of stricter environment protection regulations resulted in increasing costs for wineries as their treatment process constitutes an unavoidable and expensive step in wine production. We propose here an alternative method to reduce waste and add value to wine production by exploiting this rich carbon source and use it as a raw material for producing carbon quantum dots (CQDs). A complete synthetic pathway is discussed, comprising the carbonization of the starting material, the screening of the most suitable solvent for the extraction of CQDs from the carbonized mass and their hydrophobic or hydrophilic functionalization. CQDs synthesized with the reported procedure show a bright blue emission (λmax = 433 ± 13 nm) when irradiated at 366 nm, which is strongly shifted when the wavelength is increased (e.g. emission at around 515 nm when excited at 460 nm). Yields and luminescent properties of CQDs, obtained with two different methods, namely microwave and ultrasound-based extraction, are discussed and compared. This study shows how easy a residue can be converted into an added-value material, thus not only reducing waste and saving costs for the wine-manufacturing industry but also providing a reliable, affordable and sustainable source for valuable materials.

Synthesis of hydrophilic and hydrophobic carbon quantum dots from waste of wine fermentation

PubMed Central

Varisco, Massimo; Zufferey, Denis; Ruggi, Albert; Zhang, Yucheng; Erni, Rolf

2017-01-01

Wine lees are one of the main residues formed in vast quantities during the fermentation of wine. While toxic when applied to plants and wetlands, it is a biodegradable material, and several alternatives have been proposed for its valorization as: dietary supplement in animal feed, source for various yeast extracts and bioconversion feedstock. The implementation of stricter environment protection regulations resulted in increasing costs for wineries as their treatment process constitutes an unavoidable and expensive step in wine production. We propose here an alternative method to reduce waste and add value to wine production by exploiting this rich carbon source and use it as a raw material for producing carbon quantum dots (CQDs). A complete synthetic pathway is discussed, comprising the carbonization of the starting material, the screening of the most suitable solvent for the extraction of CQDs from the carbonized mass and their hydrophobic or hydrophilic functionalization. CQDs synthesized with the reported procedure show a bright blue emission (λmax = 433 ± 13 nm) when irradiated at 366 nm, which is strongly shifted when the wavelength is increased (e.g. emission at around 515 nm when excited at 460 nm). Yields and luminescent properties of CQDs, obtained with two different methods, namely microwave and ultrasound-based extraction, are discussed and compared. This study shows how easy a residue can be converted into an added-value material, thus not only reducing waste and saving costs for the wine-manufacturing industry but also providing a reliable, affordable and sustainable source for valuable materials. PMID:29308232

Mini-review of the geotechnical parameters of municipal solid waste: Mechanical and biological pre-treated versus raw untreated waste.

PubMed

Petrovic, Igor

2016-09-01

The most viable option for biostabilisation of old sanitary landfills, filled with raw municipal solid waste, is the so-called bioreactor landfill. Even today, bioreactor landfills are viable options in many economically developing countries. However, in order to reduce the biodegradable component of landfilled waste, mechanical and biological treatment has become a widely accepted waste treatment technology, especially in more prosperous countries. Given that mechanical and biological treatment alters the geotechnical properties of raw waste material, the design of sanitary landfills which accepts mechanically and biologically treated waste, should be carried out with a distinct set of geotechnical parameters. However, under the assumption that 'waste is waste', some design engineers might be tempted to use geotechnical parameters of untreated raw municipal solid waste and mechanical and biological pre-treated municipal solid waste interchangeably. Therefore, to provide guidelines for use and to provide an aggregated source of this information, this mini-review provides comparisons of geotechnical parameters of mechanical and biological pre-treated waste and raw untreated waste at various decomposition stages. This comparison reveals reasonable correlations between the hydraulic conductivity values of untreated and mechanical and biological pre-treated municipal solid waste. It is recognised that particle size might have a significant influence on the hydraulic conductivity of both municipal solid waste types. However, the compression ratios and shear strengths of untreated and pre-treated municipal solid waste do not show such strong correlations. Furthermore, another emerging topic that requires appropriate attention is the recovery of resources that are embedded in old landfills. Therefore, the presented results provide a valuable tool for engineers designing landfills for mechanical and biological pre-treated waste or bioreactor landfills for untreated raw waste as well as planning landfill mining projects. © The Author(s) 2016.

High-performance green flexible electronics based on biodegradable cellulose nanofibril paper

PubMed Central

Jung, Yei Hwan; Chang, Tzu-Hsuan; Zhang, Huilong; Yao, Chunhua; Zheng, Qifeng; Yang, Vina W.; Mi, Hongyi; Kim, Munho; Cho, Sang June; Park, Dong-Wook; Jiang, Hao; Lee, Juhwan; Qiu, Yijie; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang

2015-01-01

Today's consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems consisting of renewable and biodegradable materials and minimal amount of potentially toxic materials are desirable. Here we report high-performance flexible microwave and digital electronics that consume the smallest amount of potentially toxic materials on biobased, biodegradable and flexible cellulose nanofibril papers. Furthermore, we demonstrate gallium arsenide microwave devices, the consumer wireless workhorse, in a transferrable thin-film form. Successful fabrication of key electrical components on the flexible cellulose nanofibril paper with comparable performance to their rigid counterparts and clear demonstration of fungal biodegradation of the cellulose-nanofibril-based electronics suggest that it is feasible to fabricate high-performance flexible electronics using ecofriendly materials. PMID:26006731

High-performance green flexible electronics based on biodegradable cellulose nanofibril paper.

PubMed

Jung, Yei Hwan; Chang, Tzu-Hsuan; Zhang, Huilong; Yao, Chunhua; Zheng, Qifeng; Yang, Vina W; Mi, Hongyi; Kim, Munho; Cho, Sang June; Park, Dong-Wook; Jiang, Hao; Lee, Juhwan; Qiu, Yijie; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang

2015-05-26

Today's consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems consisting of renewable and biodegradable materials and minimal amount of potentially toxic materials are desirable. Here we report high-performance flexible microwave and digital electronics that consume the smallest amount of potentially toxic materials on biobased, biodegradable and flexible cellulose nanofibril papers. Furthermore, we demonstrate gallium arsenide microwave devices, the consumer wireless workhorse, in a transferrable thin-film form. Successful fabrication of key electrical components on the flexible cellulose nanofibril paper with comparable performance to their rigid counterparts and clear demonstration of fungal biodegradation of the cellulose-nanofibril-based electronics suggest that it is feasible to fabricate high-performance flexible electronics using ecofriendly materials.

High-performance green flexible electronics based on biodegradable cellulose nanofibril paper

NASA Astrophysics Data System (ADS)

Jung, Yei Hwan; Chang, Tzu-Hsuan; Zhang, Huilong; Yao, Chunhua; Zheng, Qifeng; Yang, Vina W.; Mi, Hongyi; Kim, Munho; Cho, Sang June; Park, Dong-Wook; Jiang, Hao; Lee, Juhwan; Qiu, Yijie; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang

2015-05-01

Today's consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems consisting of renewable and biodegradable materials and minimal amount of potentially toxic materials are desirable. Here we report high-performance flexible microwave and digital electronics that consume the smallest amount of potentially toxic materials on biobased, biodegradable and flexible cellulose nanofibril papers. Furthermore, we demonstrate gallium arsenide microwave devices, the consumer wireless workhorse, in a transferrable thin-film form. Successful fabrication of key electrical components on the flexible cellulose nanofibril paper with comparable performance to their rigid counterparts and clear demonstration of fungal biodegradation of the cellulose-nanofibril-based electronics suggest that it is feasible to fabricate high-performance flexible electronics using ecofriendly materials.

Research regarding biodegradable properties of food polymeric products under microorganism activity

NASA Astrophysics Data System (ADS)

Opran, Constantin; Lazar, Veronica; Fierascu, Radu Claudiu; Ditu, Lia Mara

2018-02-01

Aim of this research is the structural analysis by comparison of the biodegradable properties of two polymeric products made by non-biodegradable polymeric material (polypropylene TIPPLEN H949 A) and biodegradable polymeric material (ECOVIO IS 1335), under microorganism activity in order to give the best solution for the manufacture of food packaging biodegradable products. It presents the results of experimental determinations on comparative analysis of tensile strength for the two types of polymers. The sample weight variations after fungal biodegradation activity revealed that, after 3 months, there are no significant changes in polymeric substratum for non-biodegradable polymeric. The microscopically analysis showed that the fungal filaments did not strongly adhered on the non-biodegradable polymeric material, instead, both filamentous fungi strains adhered and covered the surface of the biodegradable sample with germinated filamentous conidia. The spectral analysis of polymer composition revealed that non-biodegradable polymer polypropylene spectra are identical for control and for samples that were exposed to fungal activity, suggesting that this type of sample was not degraded by the fungi strains. Instead, for biodegradable polymer sample, it was observed significant structural changes across multiple absorption bands, suggesting enzyme activity manifested mainly by Aspergillus niger strain. Structural analysis of interdisciplinary research results, lead, to achieving optimal injection molded technology emphasizing technological parameters, in order to obtain food packaging biodegradable products.

Whose butt is it? tobacco industry research about smokers and cigarette butt waste.

PubMed

Smith, Elizabeth A; Novotny, Thomas E

2011-05-01

Cigarette filters are made of non-biodegradable cellulose acetate. As much as 766,571 metric tons of butts wind up as litter worldwide per year. Numerous proposals have been made to prevent or mitigate cigarette butt pollution, but none has been effective; cigarette butts are consistently found to be the single most collected item in beach clean-ups and litter surveys. We searched the Legacy Tobacco Documents Library (http://legacy.library.ucsf.edu) and http://tobaccodocuments.org using a snowball strategy beginning with keywords (eg, 'filter', 'biodegradable', 'butts'). Data from approximately 680 documents, dated 1959-2006, were analysed using an interpretive approach. The tobacco industry has feared being held responsible for cigarette litter for more than 20 years. Their efforts to avoid this responsibility included developing biodegradable filters, creating anti-litter campaigns, and distributing portable and permanent ashtrays. They concluded that biodegradable filters would probably encourage littering and would not be marketable, and that smokers were defensive about discarding their tobacco butts and not amenable to anti-litter efforts. Tobacco control and environmental advocates should develop partnerships to compel the industry to take financial and practical responsibility for cigarette butt waste.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, Paul D.; Colombo, Peter

1999-07-20

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogenous molten matrix. The molten matrix may be directed in a "clean" polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, Paul D.; Colombo, Peter

1998-03-24

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogenous molten matrix. The molten matrix may be directed in a "clean" polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment.

Composition and process for the encapsulation and stabilization of radioactive hazardous and mixed wastes

DOEpatents

Kalb, Paul D.; Colombo, Peter

1997-01-01

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogenous molten matrix. The molten matrix may be directed in a "clean" polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment.

Effect of alkaline pretreatment on anaerobic digestion of olive mill solid waste.

PubMed

Pellera, Frantseska-Maria; Santori, Sofia; Pomi, Raffaella; Polettini, Alessandra; Gidarakos, Evangelos

2016-12-01

The present study evaluates the influence of alkaline (NaOH) pretreatment on anaerobic digestion of olive pomace. Batch hydrolysis experiments with different NaOH dosages, process durations and temperatures were conducted, in which the variation of olive pomace solubilization in the liquid phase was investigated. The effect of pretreatment on anaerobic digestion was studied through biochemical methane potential assays. The results demonstrated the effectiveness of the NaOH pretreatment in improving olive pomace solubilization as well as its biodegradability. Maximum specific methane yields were achieved at different NaOH dosages depending on the pretreatment temperature. Consequently, it was concluded that the two operating parameters of the pretreatment stage (NaOH dosage and temperature) may exert a joint effect on substrate biodegradability and methane yields. The highest methane yield (242NmLCH 4 /gVS) was obtained for the material pretreated at 90°C, at a dosage of 1mmol/gVS (4% of VS). Copyright © 2016 Elsevier Ltd. All rights reserved.

Kinetic modelling of anaerobic hydrolysis of solid wastes, including disintegration processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

García-Gen, Santiago; Sousbie, Philippe; Rangaraj, Ganesh

2015-01-15

Highlights: • Fractionation of solid wastes into readily and slowly biodegradable fractions. • Kinetic coefficients estimation from mono-digestion batch assays. • Validation of kinetic coefficients with a co-digestion continuous experiment. • Simulation of batch and continuous experiments with an ADM1-based model. - Abstract: A methodology to estimate disintegration and hydrolysis kinetic parameters of solid wastes and validate an ADM1-based anaerobic co-digestion model is presented. Kinetic parameters of the model were calibrated from batch reactor experiments treating individually fruit and vegetable wastes (among other residues) following a new protocol for batch tests. In addition, decoupled disintegration kinetics for readily and slowlymore » biodegradable fractions of solid wastes was considered. Calibrated parameters from batch assays of individual substrates were used to validate the model for a semi-continuous co-digestion operation treating simultaneously 5 fruit and vegetable wastes. The semi-continuous experiment was carried out in a lab-scale CSTR reactor for 15 weeks at organic loading rate ranging between 2.0 and 4.7 g VS/L d. The model (built in Matlab/Simulink) fit to a large extent the experimental results in both batch and semi-continuous mode and served as a powerful tool to simulate the digestion or co-digestion of solid wastes.« less

Materials derived from biomass/biodegradable materials.

PubMed Central

Luzier, W D

1992-01-01

Interest in biodegradable plastics made from renewable resources has increased significantly in recent years. PHBV (polyhydroxybutyrate-polyhydroxyvalerate) copolymers are good examples of this type of materials. This paper provides an overview of the manufacturing process, properties, biodegradability, and application/commercial issues associated with PHBV copolymers. They are naturally produced by bacteria from agricultural raw materials, and they can be processed to make a variety of useful products, where their biodegradability and naturalness are quite beneficial. PHBV copolymers are still in the first stage of commercialization. But they are presented in this paper as an example of how new technology can help meet society's needs for plastics and a clean environment. Images PMID:1736301

Biodegradable and edible gelatine actuators for use as artificial muscles

NASA Astrophysics Data System (ADS)

Chambers, L. D.; Winfield, J.; Ieropoulos, I.; Rossiter, J.

2014-03-01

The expense and use of non-recyclable materials often requires the retrieval and recovery of exploratory robots. Therefore, conventional materials such as plastics and metals in robotics can be limiting. For applications such as environmental monitoring, a fully biodegradable or edible robot may provide the optimum solution. Materials that provide power and actuation as well as biodegradability provide a compelling dimension to future robotic systems. To highlight the potential of novel biodegradable and edible materials as artificial muscles, the actuation of a biodegradable hydrogel was investigated. The fabricated gelatine based polymer gel was inexpensive, easy to handle, biodegradable and edible. The electro-mechanical performance was assessed using two contactless, parallel stainless steel electrodes immersed in 0.1M NaOH solution and fixed 40 mm apart with the strip actuator pinned directly between the electrodes. The actuation displacement in response to a bias voltage was measured over hydration/de-hydration cycles. Long term (11 days) and short term (1 hour) investigations demonstrated the bending behaviour of the swollen material in response to an electric field. Actuation voltage was low (<10 V) resulting in a slow actuation response with large displacement angles (<55 degrees). The stability of the immersed material decreased within the first hour due to swelling, however, was recovered on de-hydrating between actuations. The controlled degradation of biodegradable and edible artificial muscles could help to drive the development of environmentally friendly robotics.

Synergistic effect of calcium stearate and photo treatment on the rate of biodegradation of low density polyethylene spent saline vials.

PubMed

Carol, D; Karpagam, S; Kingsley, S J; Vincent, S

2012-07-01

The biodegradation of spent saline bottles, a low density polyethylene product (LDPE) by two selected Arthrobacter sp. under in vitro conditions is reported. Chemical and UV pretreatment play a vital role in enhancing the rate of biodegradation. Treated LDPE film exhibits a higher weight loss and density when compared to untreated films. Arthrobacter oxydans and Arthrobacter globiformis grew better in medium containing pretreated film than in medium containing untreated film. The decrease in density and weight loss of LDPE was also more for pretreated film when compared to untreated film indicating the affect of abiotic treatment on mechanical properties of LDPE. The decrease in the absorbance corresponding to carbonyl groups and double bonds that were generated during pretreatment suggest that some of the double bonds were cut by Arthrobacter species. Since Arthrobacter sp. are capable of degrading urea, splitting of urea group were also seen in FTIR spectrum indicating the evidence of biodegradation after microbial incubation. The results indicated that biodegradation rate could be enhanced by exposing LDPE to calcium stearate (a pro-oxidant) which acts as an initiator for the oxidation of the polymers leading to a decrease of molecular weight and formation of hydrophilic group. Therefore, the initial step for biodegradation of many inert polymers depends on a photo-oxidation of those polymers. The application in sufficient details with improved procedures utilizing recombinant microorganism with polymer degradation capacity can lead to a better plastic waste management in biomedical field. The present plastic disposal trend of waste accumulation can be minimized with this promising eco-friendly technique.

Impact of vent pipe diameter on characteristics of waste degradation in semi-aerobic bioreactor landfill.

PubMed

Jiang, Guobin; Liu, Dan; Chen, Weiming; Ye, Zhicheng; Liu, Hong; Li, Qibin

2017-10-01

The evolution mechanism of a vent pipe diameter on a waste-stabilization process in semi-aerobic bioreactor landfills was analyzed from the organic-matter concentration, biodegradability, spectral characteristics of dissolved organic matter, correlations and principal-component analysis. Waste samples were collected at different distances from the vent pipe and from different landfill layers in semi-aerobic bioreactor landfills with different vent pipe diameters. An increase in vent pipe diameter favored waste degradation. Waste degradation in landfills can be promoted slightly when the vent pipe diameter increases from 25 to 50 mm. It could be promoted significantly when the vent pipe diameter was increased to 75 mm. The vent pipe diameter is important in waste degradation in the middle layer of landfills. The dissolved organic matter in the waste is composed mainly of long-wave humus (humin), short-wave humus (fulvic acid) and tryptophan. The humification levels of the waste that was located at the center of vent pipes with 25-, 50- and 75-mm diameters were 2.2682, 4.0520 and 7.6419 Raman units, respectively. The appropriate vent pipe diameter for semi-aerobic bioreactor landfills with an 800-mm diameter was 75 mm. The effect of different vent pipe diameters on the degree of waste stabilization is reflected by two main components. Component 1 is related mainly to the content of fulvic acid, biologically degradable material and organic matter. Component 2 is related mainly to the content of tryptophan and humin from the higher vascular plants.

Materials, Processes, and Facile Manufacturing for Bioresorbable Electronics: A Review.

PubMed

Yu, Xiaowei; Shou, Wan; Mahajan, Bikram K; Huang, Xian; Pan, Heng

2018-05-07

Bioresorbable electronics refer to a new class of advanced electronics that can completely dissolve or disintegrate with environmentally and biologically benign byproducts in water and biofluids. They have provided a solution to the growing electronic waste problem with applications in temporary usage of electronics such as implantable devices and environmental sensors. Bioresorbable materials such as biodegradable polymers, dissolvable conductors, semiconductors, and dielectrics are extensively studied, enabling massive progress of bioresorbable electronic devices. Processing and patterning of these materials are predominantly relying on vacuum-based fabrication methods so far. However, for the purpose of commercialization, nonvacuum, low-cost, and facile manufacturing/printing approaches are the need of the hour. Bioresorbable electronic materials are generally more chemically reactive than conventional electronic materials, which require particular attention in developing the low-cost manufacturing processes in ambient environment. This review focuses on material reactivity, ink availability, printability, and process compatibility for facile manufacturing of bioresorbable electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The influence of partial replacement of hemp shives by expanded perlite on physical properties of hemp-lime composite

NASA Astrophysics Data System (ADS)

Brzyski, Przemysław; Widomski, Marcin

2017-07-01

The use of waste plants in building materials production is consistent with the principles of sustainable development, including waste management, CO2 balance, biodegradability of the material e.g. after building demolition. The porous structure of plant materials determines their usability as the insulation materials. An example of plant applicable in the construction industry is the industrial hemp. The shives are produced from the wooden core of the hemp stem as lightweight insulating filler in the composite based on lime binder. The discussed hemp-lime composite, due to the presence of lightweight, porous organic aggregates exhibits satisfactory thermal insulation properties and is used as filling and insulation of walls (as well as roofs and floors) in buildings of the wooden frame construction. The irregular shape of shives and their low density causes nonhomogenous compaction of composite and the formation of voids between the randomly arranged shives. In this paper the series of hemp-lime composites were tested. Apart from hemp shives, an additional aggregate - expanded perlite was used as a fine, lightweight, thermal insulating filler. Application of the additional aggregate was aimed to fill the voids between hemp shives and to investigate its influence on the physical properties of composite: apparent density, total porosity, water absorption and thermal conductivity.

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.

Simulating settlement during waste placement at a landfill with waste lifts placed under frozen conditions.

PubMed

Van Geel, Paul J; Murray, Kathleen E

2015-12-01

Twelve instrument bundles were placed within two waste profiles as waste was placed in an operating landfill in Ste. Sophie, Quebec, Canada. The settlement data were simulated using a three-component model to account for primary or instantaneous compression, secondary compression or mechanical creep and biodegradation induced settlement. The regressed model parameters from the first waste layer were able to predict the settlement of the remaining four waste layers with good agreement. The model parameters were compared to values published in the literature. A MSW landfill scenario referenced in the literature was used to illustrate how the parameter values from the different studies predicted settlement. The parameters determined in this study and other studies with total waste heights between 15 and 60 m provided similar estimates of total settlement in the long term while the settlement rates and relative magnitudes of the three components varied. The parameters determined based on studies with total waste heights less than 15m resulted in larger secondary compression indices and lower biodegradation induced settlements. When these were applied to a MSW landfill scenario with a total waste height of 30 m, the settlement was overestimated and provided unrealistic values. This study concludes that more field studies are needed to measure waste settlement during the filling stage of landfill operations and more field data are needed to assess different settlement models and their respective parameters. Copyright © 2015 Elsevier Ltd. All rights reserved.

Application of Bioelectrochemical Process (BES) for Electricity Generation and Sustainable Wastewater Treatment

NASA Astrophysics Data System (ADS)

Kim, Jung Rae

Bioelectrochemical system such as microbial fuel cells (MFCs) and microbial electrolysis cell are an emerging technology which converts biodegradable organic matter to electrical energy or hydrogen using a biofilm on the electrode as the biocatalyst. It has recently been shown that waste-to-energy technology based on MFC can treat organic contaminant in domestic or industrial wastewater and simultaneously produce electricity. The maximum power density increased up to 1kW/m3 based on reactor volume. Bioelectrochemical systems may reduce the energy consumption for wastewater treatment by replacing energy intensive aeration of present treatment systems, while generate electrical energy from waste. In addition, the biomass production in MFCs has been reported to be 10-50% of conventional wastewater treatment, leading to reduce environmental impact and disposal costs. Various electrochemically active bacteria metabolize biodegradable organic compounds then discharge electrons to an extracellular electron acceptor for bacterial respiration. These bacteria also transfer electrons to electrodes by direct electron transfer, electron mediators or shuttles, and electrically conductive nanowires. Investigation of bacterial electron transport mechanisms may improve understanding of the biomaterial involved and metabolic pathways as well as improving power from MFCs. Biofuel cell systems require interdisciplinary research ranging from electrochemistry, microbiology, material science and surface chemistry to engineering such as reactor design, operation and modelling. Collaboration within each study and integration of systems might increase the performance and feasibility of BES process for sustainable energy.

Macrofouling communities and the degradation of plastic bags in the sea: an in situ experiment

PubMed Central

Petermann, Jana S.; Lott, Christian; Weber, Miriam

2017-01-01

The increasing amount of plastic littered into the sea may provide a new substratum for benthic organisms. These marine fouling communities on plastic have not received much scientific attention. We present, to our knowledge, the first comprehensive analysis of their macroscopic community composition, their primary production and the polymer degradation comparing conventional polyethylene (PE) and a biodegradable starch-based plastic blend in coastal benthic and pelagic habitats in the Mediterranean Sea. The biomass of the fouling layer increased significantly over time and all samples became heavy enough to sink to the seafloor. The fouling communities, consisting of 21 families, were distinct between habitats, but not between polymer types. Positive primary production was measured in the pelagic, but not in the benthic habitat, suggesting that large accumulations of floating plastic could pose a source of oxygen for local ecosystems, as well as a carbon sink. Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies. PMID:29134070

Simulating the heat budget for waste as it is placed within a landfill operating in a northern climate.

PubMed

Megalla, Dina; Van Geel, Paul J; Doyle, James T

2016-09-01

A landfill gas to energy (LFGTE) facility in Ste. Sophie, Quebec was instrumented with sensors which measure temperature, oxygen, moisture content, settlement, total earth pressure, electrical conductivity and mounding of leachate. These parameters were monitored during the operating phase of the landfill in order to better understand the biodegradation and waste stabilization processes occurring within a LFGTE facility. Conceptual and numerical models were created to describe the heat transfer processes which occur within five waste lifts placed over a two-year period. A finite element model was created to simulate the temperatures within the waste and estimate the heat budget over a four and a half year period. The calibrated model was able to simulate the temperatures measured to date within the instrumented waste profile at the site. The model was used to evaluate the overall heat budget for the waste profile. The model simulations and heat budget provide a better understanding of the heat transfer processes occurring within the landfill and the relative impact of the various heat source/sink and storage terms. Aerobic biodegradation appears to play an important role in the overall heat budget at this site generating 36% of the total heat generated within the waste profile during the waste placement stages of landfill operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biodegradation of food waste using microbial cultures producing thermostable α-amylase and cellulase under different pH and temperature.

PubMed

Awasthi, Mukesh Kumar; Wong, Jonathan W C; Kumar, Sunil; Awasthi, Sanjeev Kumar; Wang, Quan; Wang, Meijing; Ren, Xiuna; Zhao, Junchao; Chen, Hongyu; Zhang, Zengqiang

2018-01-01

The aim of this work was to study the biodegradation of food waste employing thermostable α-amylase and cellulase enzymes producing bacteria. Four potential isolates were identified which were capable of producing maximum amylase and cellulase and belong to the amylolytic strains, Brevibacillus borstelensis and Bacillus licheniformis; cellulolytic strains, Bacillus thuringiensis and Bacillus licheniformis, respectively. These strains were selected based on its higher cell density, enzymatic activities and stability at a wide range of pH and temperature compared to other strains. The results indicated that 1:1 ratio of pre and post consumed food wastes (FWs) were helpful to facilitate the degradation employing bacterial consortium. In addition, organic matter decomposition and chemical parameters of the end product quality also indicated that bacterial consortium was very effective for 1:1 ratio of FWs degradation as compared to the other treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enhancing biogas production from anaerobic biodegradation of the organic fraction of municipal solid waste through leachate blending and recirculation.

PubMed

Nair, Arjun; Sartaj, Majid; Kennedy, Kevin; Coelho, Nuno M G

2014-10-01

Leachate recirculation has a profound advantage on biodegradation of the organic fraction of municipal solid waste in landfills. Mature leachate from older sections of landfills (>10 years) and young leachate were blended and added to organic fraction of municipal solid waste in a series of biomethane potential assay experiments with different mixing ratios of mature and young leachate and their effect on biogas production was monitored. The improvement in biogas production was in the range of 19%-41% depending on the ratio of mixing old and new leachate. The results are conclusive that the biogas generation could be improved by blending the old and new leachate in a bioreactor landfill system as compared with a conventional system employed in bioreactor landfills today for recirculating the same age leachate. © The Author(s) 2014.

Leachate pre-treatment strategies before recirculation in landfill bioreactors.

PubMed

Vigneron, V; Bouchez, T; Bureau, C; Mailly, N; Mazeas, L; Duquennoi, C; Audic, J M; Hébé, L; Bernet, N

2005-01-01

Nitrified leachate recirculation represents a promising strategy for a more sustainable landfill management. Our objective was to determine the reactions involved in nitrate reduction in municipal solid waste batch biodegradation tests. Anaerobic digestion of waste in the three control reactors showed a good reproducibility. In two test reactors, nitrate was added at various moments of the waste degradation process. We observed that: (1) H2S concentration controlled the nitrate reduction pathway: above a certain threshold of H2S, dissimilatory nitrate reduction to ammonium (DNRA) replaced denitrification. (2) N2O/N2 ratio varied with the organic carbon concentration: the lower the easily biodegradable carbon concentration, the higher the N2O/N2 ratio. (3) N2 was consumed after denitrification. The possibility of a nitrogen fixation reaction in the presence of NH4 is discussed. Nitrified leachate recirculation during acidogenesis should be avoided because of higher H2S production which could induce DNRA.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guardia, A. de, E-mail: amaury.de-guardia@cemagref.f; Universite Europeenne de Bretagne, F-35000 Rennes; Mallard, P.

This paper aimed to compare household waste, separated pig solids, food waste, pig slaughterhouse sludge and green algae regarding processes ruling nitrogen dynamic during composting. For each waste, three composting simulations were performed in parallel in three similar reactors (300 L), each one under a constant aeration rate. The aeration flows applied were comprised between 100 and 1100 L/h. The initial waste and the compost were characterized through the measurements of their contents in dry matter, total carbon, Kjeldahl and total ammoniacal nitrogen, nitrite and nitrate. Kjeldahl and total ammoniacal nitrogen and nitrite and nitrate were measured in leachates andmore » in condensates too. Ammonia and nitrous oxide emissions were monitored in continue. The cumulated emissions in ammonia and in nitrous oxide were given for each waste and at each aeration rate. The paper focused on process of ammonification and on transformations and transfer of total ammoniacal nitrogen. The parameters of nitrous oxide emissions were not investigated. The removal rate of total Kjeldahl nitrogen was shown being closely tied to the ammonification rate. Ammonification was modelled thanks to the calculation of the ratio of biodegradable carbon to organic nitrogen content of the biodegradable fraction. The wastes were shown to differ significantly regarding their ammonification ability. Nitrogen balances were calculated by subtracting nitrogen losses from nitrogen removed from material. Defaults in nitrogen balances were assumed to correspond to conversion of nitrate even nitrite into molecular nitrogen and then to the previous conversion by nitrification of total ammoniacal nitrogen. The pool of total ammoniacal nitrogen, i.e. total ammoniacal nitrogen initially contained in waste plus total ammoniacal nitrogen released by ammonification, was calculated for each experiment. Then, this pool was used as the referring amount in the calculation of the rates of accumulation, stripping and nitrification of total ammoniacal nitrogen. Separated pig solids were characterised by a high ability to accumulate total ammoniacal nitrogen. Whatever the waste, the striping rate depended mostly on the aeration rate and on the pool concentration in biofilm. The nitrification rate was observed as all the higher as the concentration in total ammoniacal nitrogen in the initial waste was low. Thus, household waste and green algae exhibited the highest nitrification rates. This result could mean that in case of low concentrations in total ammoniacal nitrogen, a nitrifying biomass was already developed and that this biomass consumed it. In contrast, in case of high concentrations, this could traduce some difficulties for nitrifying microorganisms to develop.« less

Biodegradable bioplastics from food wastes

USDA-ARS?s Scientific Manuscript database

An estimated 1.8 billion tons of waste are created annually from food processing in the US, including the peels, pulp, and pomace (PPP) generated from fruits and vegetables when they are converted into frozen or canned products or pressed into juice. PPP currently is sold as animal feed at low cost,...

Ammonium and skatole biodegradation by swine waste microflora in a flow-through bioreactor

USDA-ARS?s Scientific Manuscript database

Animal waste disposal and odor control have become a major issue for animal production facilities. As an attempt to improve efficiency and profit margins, many livestock operations have become large concentrated rearing facilities. As a result, many concerns over potentially adverse environmental im...

PROPOSED PROCESS FOR MANAGEMENT OF TEXTILE WASTE FROM REDESIGNED SECONDHAND CLOTHING PRODUCTION IN HAITI: NO-WASTE, RECYCLING AND REPURPOSING

EPA Science Inventory

Outputs of this project include a “redesign matrix” created by apparel design faculty members and graduate students and a “biodegradable/recyclable fabric matrix” created by both fiber science and apparel design students and faculty – both with...

Generation of Valuable Nanomaterials Using Biodegradable Waste: Rags to Riches Story of Red Grape Pomace

EPA Science Inventory

In our sustainable research endeavors pertaining to environmental remediation, we envisioned utilizing winery waste, red grape pomace, as a primary source for the dual role of reduction of inorganic salts and capping of the ensuing nanomaterials This study shows that red grape po...

Performance Test on Polymer Waste Form - 12137

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Se Yup

Polymer solidification was attempted to produce stable waste form for the boric acid concentrates and the dewatered spent resins. The polymer mixture was directly injected into the mold or drum which was packed with the boric acid concentrates and the dewatered spent resins, respectively. The waste form was produced by entirely curing the polymer mixture. A series of performance tests was conducted including compressive strength test, water immersion test, leach test, thermal stability test, irradiation stability test and biodegradation stability test for the polymer waste forms. From the results of the performance tests for the polymer waste forms, it ismore » believed that the polymer waste form is very stable and can satisfy the acceptance criteria for permanent disposal. At present, performance tests with full scale polymer waste forms are being carried out in order to obtain qualification certificate by the regulatory institute in Korea. Polymer waste forms were prepared with the surrogate of boric acid concentrates and the surrogate of spent ion exchange resins respectively. Waste forms were also made in lab scale and in full scale. Lab. scale waste forms were directly subjected to a series of the performance tests. In the case of full scale waste form, the test specimens for the performance test were taken from a part of waste form by coring. A series of performance tests was conducted including compressive strength test, thermal stability test, irradiation stability test and biodegradation stability test, water immersion test, leach test, and free standing water for the polymer waste forms. In addition, a fire resistance test was performed on the waste forms by the requirement of the regulatory institute in Korea. Every polymer waste forms containing the boric acid concentrates and the spent ion exchange resins had exhibited excellent structural integrity of more than 27.58 MPa (4,000 psi) of compressive strength. On thermal stability testing, biodegradation testing and water immersion testing, no degradation was observed in the waste forms. Also, by measuring the compressive strength after these tests, it was confirmed that the structural integrity was still retained. A leach test was performed by using non radioactive cobalt, cesium and strontium. The leaching of cobalt, cesium and strontium from the polymer waste forms was very low. Also, the polymer waste forms were found to possess adequate fire resistance. From the results of the performance tests, it is believed that the polymer waste form is very stable and can satisfy the acceptance criteria for permanent disposal. At present, Performance tests with full scale polymer waste forms are on-going in order to obtain qualification certificate by the regulatory institute in Korea. (authors)« less

Transesterification of sago starch and waste palm cooking oil in densified CO2

NASA Astrophysics Data System (ADS)

Muljana, H.; Sugih, A. K.; Christina, N.; Fangdinata, K.; Renaldo, J.; Rudy; Heeres, H. J.; Picchioni, F.

2017-07-01

In this work, the synthesis of biodegradable and yet renewable thermoplastics materials through a transesterification reaction of sago starch and waste palm cooking oil (WPO) in densified CO2 as the solvent is reported. The aim of this research is to investigate the potential used of sago starch and WPO as raw materials in the thermoplastics starch synthesis. The starch esters was successfully synthesized using sago starch and WPO as reagent in densified CO2 as shown from the presence of carbonyl group (C=O, 1743 cm-1) in the FT-IR spectra coupled with the presence of the proton (1H-NMR) of the fatty acid in the starch backbone (0.8 - 2 ppm). The product crystallinity decreases as shown in XRD results and resulting with a change in the thermal properties (melting and crystalline temperature) of the products. In addition, the products show a different granular morphology and a higher hydrophobicity compared with native sago starch. This research shows the potential used of sago starch and WPO in the thermoplastics starch synthesis and opens a new perspective on the product application.

Evaluation of select blends of cotton byproducts in the manufacture of biodegradable packaging material

USDA-ARS?s Scientific Manuscript database

Polystyrene is one of the most widely used plastics in the manufacture of packaging materials. Extruded polystyrene foam is commonly sold under the trademark name of StyrofoamTM. Polystyrene packaging is a multibillion dollar a year industry. Since polystyrene is non-biodegradable, a biodegradable m...

[The research of biodegradation of a composite material used in reconstructive and reparative surgery of maxillofacial area].

PubMed

Malanchuk, V O; Astapenko, O O; Halatenko, N A; Rozhnova, R A

2013-09-01

Dates about the research of biodegradation of epoxy-polyurethane composite material used in reconstructive and reparative surgery of maxillofacial area are reflected in the article. Was founded: 1) notable biodegradation of species from epoxy-polyurethane composition in the term of observation up to 6 months was not founded. That testifies their preservation of physical and mechanical properties. 2) founded, that in species from epoxy-polyurethane composition, which contain levamisole, processes of biodegradation are faster then in species from pure epoxy-polyurethane composition and in species from epoxy-polyurethane composition with hydroxyapatite; 3) material from epoxy-polyurethane composition, which contains levamisole and hydroxyapatite, stays in biological environment in small quantity of petty fragments during the incubation in term of 2 years. So, it biodegrades practically totally. Authors suggest on the basis of achieved information, that the use of epoxy-polyurethane constructions that biodegrade, is pertinently in reconstructive maxillofacial surgery.

A review on biodegradable materials for cardiovascular stent application

NASA Astrophysics Data System (ADS)

Hou, Li-Da; Li, Zhen; Pan, Yu; Sabir, MuhammadIqbal; Zheng, Yu-Feng; Li, Li

2016-09-01

A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.

Degradation of sustainable mulch materials in two types of soil under laboratory conditions

NASA Astrophysics Data System (ADS)

Villena, Jaime; González, Sara; Moreno, Carmen; Aceituno, Patricia; Campos, Juan; Meco, Ramón; María Moreno, Marta

2017-04-01

Mulching is a technique used in cultivation worldwide, especially for vegetable crops, for reducing weed growth, minimising or eliminating soil erosion, and often for enhancing total yields. Manufactured plastic films, mainly polyethylene (PE), have been widely used for this purpose due to their excellent mechanical properties, light weight and relatively low prices in recent years. However, the use of PE is associated with serious environmental problems related to its petrochemical origin and its long shelf-life, which causes a waste problem in our crop fields. For this reason, the use of biodegradable mulch materials (biopolymers and papers) as alternative to PE is increasing nowadays, especially in organic farming. However, these materials can suffer an undesirable early degradation (and therefore not fulfilling their function successfully), greatly resulting from the type of soil. For this reason, this study aimed to analyse the degradation pattern of different mulch materials buried in two types of soils, clay and sand, under laboratory conditions (25°C, dark surroundings, constant humidity). The mulch materials used were: 1) black polyethylene (15 µm); black biopolymers (15 µm): 2) maize starch-based, 3) potato starch-based, 4) polylactic acid-based, 5) black paper, 85 g/m2. Periodically (every 15-20 days), the weight and surface loss of the different materials were recorded. The results indicate that mulch degradation was earlier and higher in the clay soil, especially in the paper and in the potato starch-based materials, followed by the maize starch-based mulch, while polylactic acid-based suffered the least and the latest degradation. Keywords: mulch, biodegradable, biopolymer, paper, degradation. Acknowledgements: the research was funded by Project RTA2011-00104-C04-03 from the INIA (Spanish Ministry of Economy and Competitiveness).

Thermal properties of light-weight concrete with waste polypropylene aggregate

NASA Astrophysics Data System (ADS)

Záleská, Martina; Pokorný, Jaroslav; Pavlíková, Milena; Pavlík, Zbyšek

2017-07-01

Thermal properties of a sustainable light-weight concrete incorporating high volume of waste polypropylene as partial substitution of natural aggregate were studied in the paper. Glass fiber reinforced polypropylene (GFPP), a by-product of PP tubes production, partially substituted fine natural silica aggregate in 10, 20, 30, 40, and 50 mass%. In order to quantify the effect of GFPP use on concrete properties, a reference concrete mix without plastic waste was studied as well. For the applied GFPP, bulk density, matrix density, and particle size distribution were measured. Specific attention was paid to thermal transport and storage properties of GFPP that were examined in dependence on compaction time. For the developed light-weight concrete, thermal properties were accessed using transient impulse technique, whereas the measurement was done in dependence on moisture content, from the dry state to fully water saturated state. Additionally, the investigated thermal properties were plotted as function of porosity. The tested light-weight concrete was found to be prospective construction material possessing improved thermal insulation function. Moreover, the reuse of waste plastics in concrete composition was beneficial both from the environmental and financial point of view considering plastics low biodegradability and safe disposal.

Comprehensive Planning for Classification and Disposal of Solid Waste at the Industrial Parks regarding Health and Environmental Impacts

PubMed Central

Rahmani Samani, Bahareh

2014-01-01

The aim of this study is the comprehensive planning for integrated management of solid waste at the industrial parks. The share of each industrial group including food, metal, chemical, non-metallic minerals, textile, electrical and electronical, and cellulose industries were 48.2, 14.9, 6.7, 22, 0.9, 0.6, and 6.5 percent, respectively. The results showed that nearly half of total industrial waste produced from the range of biological materials are biodegradable and discharging them without observing environmental regulations leads to short-term pollution and nuisance in the acceptor environment. Also some parts of case study waste were recyclable which is considerable from viewpoint of economical and environmental pollution. Long-term impacts will appear due to improper site selection of disposal from the spatial standpoint. In this way, an approach for site selection using several socioeconomic, physical, and environmental criteria based on multicriteria decision making model (MCDM) is introduced. Health risks and environment pollution such as soil and surface water may be done. It is essential to revise the studied industries layout, particularly those units which produce special waste which should be more cautious. Also stricter enforcement is required as an effective step in reducing the harmful impacts of it. PMID:24688552

Comprehensive planning for classification and disposal of solid waste at the industrial parks regarding health and environmental impacts.

PubMed

Hashemi, Hassan; Pourzamani, Hamidreza; Rahmani Samani, Bahareh

2014-01-01

The aim of this study is the comprehensive planning for integrated management of solid waste at the industrial parks. The share of each industrial group including food, metal, chemical, non-metallic minerals, textile, electrical and electronical, and cellulose industries were 48.2, 14.9, 6.7, 22, 0.9, 0.6, and 6.5 percent, respectively. The results showed that nearly half of total industrial waste produced from the range of biological materials are biodegradable and discharging them without observing environmental regulations leads to short-term pollution and nuisance in the acceptor environment. Also some parts of case study waste were recyclable which is considerable from viewpoint of economical and environmental pollution. Long-term impacts will appear due to improper site selection of disposal from the spatial standpoint. In this way, an approach for site selection using several socioeconomic, physical, and environmental criteria based on multicriteria decision making model (MCDM) is introduced. Health risks and environment pollution such as soil and surface water may be done. It is essential to revise the studied industries layout, particularly those units which produce special waste which should be more cautious. Also stricter enforcement is required as an effective step in reducing the harmful impacts of it.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choung, Sungwook; Um, Wooyong; Pacific Northwest National Laboratory

Permanent disposal of low- and intermediate-level radioactive wastes in the subterranean environment has been the preferred method of many countries, including Korea. A safety issue after the closure of a geological repository is that biodegradation of organic materials due to microbial activities generates gases that lead to overpressure of the waste containers in the repository and its disintegration with the release of radionuclides. As part of an ongoing large-scale in situ experiment using organic wastes and groundwater to simulate geological radioactive waste repository conditions, we investigated the geochemical alteration and microbial activities at an early stage (~63 days) intended tomore » be representative of the initial period after repository closure. The increased numbers of both aerobes and facultative anaerobes in waste effluents indicate that oxygen content could be the most significant parameter to control biogeochemical conditions at very early periods of reaction (<35 days). Accordingly, the values of dissolved oxygen and redox potential were decreased. The activation of anaerobes after 35 days was supported by the increased concentration to ~50 mg L-1 of ethanol. These results suggest that the biogeochemical conditions were rapidly altered to more reducing and anaerobic conditions within the initial 2 months after repository closure. Although no gases were detected during the study, activated anaerobic microbes will play more important role in gas generation over the long term.« less

Catalytic Pyrolysis of Waste Plastic Mixture

NASA Astrophysics Data System (ADS)

Sembiring, Ferdianta; Wahyu Purnomo, Chandra; Purwono, Suryo

2018-03-01

Inorganic waste especially plastics still become a major problem in many places. Low biodegradability of this materials causes the effort in recycling become very difficult. Most of the municipal solid waste (MSW) recycling facilities in developing country only use composting method to recover the organic fraction of the waste, while the inorganic fraction is still untreated. By pyrolysis, plastic waste can be treated to produce liquid fuels, flammable gas and chars. Reduction in volume and utilization of the liquid and gas as fuel are the major benefits of the process. By heat integration actually this process can become a self-sufficient system in terms of energy demand. However, the drawback of this process is usually due to the diverse type of plastic in the MSW creating low grade of liquid fuel and harmful gases. In this study, the mixture of plastics i.e. polypropylene (PP) and polyethylene terephthalate (PET) is treated using pyrolysis with catalyst in several operating temperature. PET is problematic to be treated using pyrolysis due to wax-like byproduct in liquid which may cause pipe clogging. The catalyst is the mixture of natural zeolite and bentonite which is able to handle PP and PET mixture feed to produce high grade liquid fuels in terms of calorific value and other fuel properties.

Comparison of methane production potential, biodegradability, and kinetics of different organic substrates.

PubMed

Li, Yeqing; Zhang, Ruihong; Liu, Guangqing; Chen, Chang; He, Yanfeng; Liu, Xiaoying

2013-12-01

The methane production potential, biodegradability, and kinetics of a wide range of organic substrates were determined using a unified and simple method. Results showed that feedstocks that contained high energy density and easily degradable substrates exhibited high methane production potential and biodegradability. Lignocellulosic biomass with high content of fibrous compositions had low methane yield and biodegradability. Feedstocks with high lignin content (≥ 15%, on a TS basis) had low first-order rate constant (0.05-0.06 1/d) compared to others. A negative linear correlation between lignin content and experimental methane yield (or biodegradability) was found for lignocellulosic and manure wastes. This could be used as a fast method to predict the methane production potential and biodegradability of fiber-rich substrates. The findings of this study provided a database for the conversion efficiency of different organic substrates and might be useful for applications of biomethane potential assay and anaerobic digestion in the future. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fungal communities associated with the biodegradation of polyester polyurethane buried under compost at different temperatures.

PubMed

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.

Fungal Communities Associated with the Biodegradation of Polyester Polyurethane Buried under Compost at Different Temperatures

PubMed Central

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

Composition and process for the encapsulation and stabilization of radioactive hazardous and mixed wastes

DOEpatents

Kalb, P.D.; Colombo, P.

1997-07-15

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogeneous molten matrix. The molten matrix may be directed in a ``clean`` polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment. 2 figs.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, P.D.; Colombo, P.

1998-03-24

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogeneous molten matrix. The molten matrix may be directed in a ``clean`` polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment. 2 figs.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, P.D.; Colombo, P.

1999-07-20

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogeneous molten matrix. The molten matrix may be directed in a clean'' polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment. 2 figs.

Co-ensiling as a new technique for long-term storage of agro-industrial waste with low sugar content prior to anaerobic digestion.

PubMed

Hillion, Marie-Lou; Moscoviz, Roman; Trably, Eric; Leblanc, Yoann; Bernet, Nicolas; Torrijos, Michel; Escudié, Renaud

2018-01-01

Biodegradable wastes produced seasonally need an upstream storage, because of the requirement for a constant feeding of anaerobic digesters. In the present article, the potential of co-ensiling biodegradable agro-industrial waste (sugar beet leaves) and lignocellulosic agricultural residue (wheat straw) to obtain a mixture with low soluble sugar content was evaluated for long-term storage prior to anaerobic digestion. The aim is to store agro-industrial waste while pretreating lignocellulosic biomass. The dynamics of co-ensiling was evaluated in vacuum-packed bags at lab-scale during 180 days. Characterization of the reaction by-products and microbial communities showed a succession of metabolic pathways. Even though the low initial sugars content was not sufficient to lower the pH under 4.5 and avoid undesirable fermentations, the methane potential was not substantially impacted all along the experiment. No lignocellulosic damages were observed during the silage process. Overall, it was shown that co-ensiling was effective to store highly fermentable fresh waste evenly with low sugar content and offers new promising possibilities for constant long-term supply of industrial anaerobic digesters. Copyright © 2017 Elsevier Ltd. All rights reserved.

The potential reuse of biodegradable municipal solid wastes (MSW) as feedstocks in vermicomposting.

PubMed

Sim, Edwin Yih Shyang; Wu, Ta Yeong

2010-10-01

There is an urgent need globally to find alternative sustainable steps to treat municipal solid wastes (MSW) originated from mismanagement of urban wastes with increasing disposal cost. Furthermore, a conglomeration of ever-increasing population and consumerist lifestyle is contributing towards the generation of more MSW. In this context, vermicomposting offers excellent potential to promote safe, hygienic and sustainable management of biodegradable MSW. It has been demonstrated that, through vermicomposting, MSW such as city garbage, household and kitchen wastes, vegetable wastes, paper wastes, human faeces and others could be sustainably transformed into organic fertiliser or vermicompost that provides great benefits to agricultural soil and plants. Generally, earthworms are sensitive to their environment and require temperature, moisture content, pH and sometimes ventilation at proper levels for the optimum vermicomposting process. Apart from setting the optimum operational conditions for the vermicomposting process, other approaches such as pre-composting, inoculating micro-organisms into MSW and redesigning the conventional vermireactor could be introduced to further enhance the vermicomposting of MSW. Thus the present mini-review discusses the potential of introducing vermicomposting in MSW management, the benefits of vermicomposted MSW to plants, suggestions on how to enhance the vermicomposting of MSW as well as risk management in the vermicomposting of MSW. Copyright © 2010 Society of Chemical Industry.

Development of biodegradable materials; balancing degradability and performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayer, J.M.; Allen, A.L.; Dell, P.A.

1993-12-31

The development of biodegradable materials suitable for packaging must take into consideration various performance criteria such as mechanical and barrier properties, as well as rate of biodegradability in given environments. Individual or blended biopolymer films were obtained commercially or blown into film in the laboratory and tested for tensile strength, ultimate elongation and oxygen barrier. These films were then subjected to accelerated marine biodegradation tests as well as simulated marine respirometry. Starch/ethylene vinyl alcohol films exhibited good mechanical and excellent oxygen barrier properties, but were very slow to biodegrade in the simulated and excellent oxygen barrier properties, but were verymore » slow to biodegrade in the simulated marine environment. Polyhydroxyalkanoates had good mechanical properties, average oxygen barrier and good biodegradability. Data indicate that performance and biodegradability of packaging can be tailored to needs by combining individual biopolymers in different proportions in blends and laminates.« less

Environmental assessment of alternative municipal solid waste management strategies. A Spanish case study.

PubMed

Bovea, M D; Ibáñez-Forés, V; Gallardo, A; Colomer-Mendoza, F J

2010-11-01

The aim of this study is to compare, from an environmental point of view, different alternatives for the management of municipal solid waste generated in the town of Castellón de la Plana (Spain). This town currently produces 207 ton of waste per day and the waste management system employed today involves the collection of paper/cardboard, glass and light packaging from materials banks and of rest waste at street-side containers. The proposed alternative scenarios were based on a combination of the following elements: selective collection targets to be accomplished by the year 2015 as specified in the Spanish National Waste Plan (assuming they are reached to an extent of 50% and 100%), different collection models implemented nationally, and diverse treatments of both the separated biodegradable fraction and the rest waste to be disposed of on landfills. This resulted in 24 scenarios, whose environmental behaviour was studied by applying the life cycle assessment methodology. In accordance with the ISO 14040-44 (2006) standard, an inventory model was developed for the following stages of the waste management life cycle: pre-collection (bags and containers), collection, transport, pre-treatment (waste separation) and treatment/disposal (recycling, composting, biogasification+composting, landfill with/without energy recovery). Environmental indicators were obtained for different impact categories, which made it possible to identify the key variables in the waste management system and the scenario that offers the best environmental behaviour. Finally, a sensitivity analysis was used to test some of the assumptions made in the initial life cycle inventory model. Copyright © 2010 Elsevier Ltd. All rights reserved.

Phyllosphere yeasts rapidly break down biodegradable plastics

PubMed Central

2011-01-01

The use of biodegradable plastics can reduce the accumulation of environmentally persistent plastic wastes. The rate of degradation of biodegradable plastics depends on environmental conditions and is highly variable. Techniques for achieving more consistent degradation are needed. However, only a few microorganisms involved in the degradation process have been isolated so far from the environment. Here, we show that Pseudozyma spp. yeasts, which are common in the phyllosphere and are easily isolated from plant surfaces, displayed strong degradation activity on films made from poly-butylene succinate or poly-butylene succinate-co-adipate. Strains of P. antarctica isolated from leaves and husks of paddy rice displayed strong degradation activity on these films at 30°C. The type strain, P. antarctica JCM 10317, and Pseudozyma spp. strains from phyllosphere secreted a biodegradable plastic-degrading enzyme with a molecular mass of about 22 kDa. Reliable source of biodegradable plastic-degrading microorganisms are now in our hands. PMID:22126328

Phyllosphere yeasts rapidly break down biodegradable plastics.

PubMed

Kitamoto, Hiroko K; Shinozaki, Yukiko; Cao, Xiao-Hong; Morita, Tomotake; Konishi, Masaaki; Tago, Kanako; Kajiwara, Hideyuki; Koitabashi, Motoo; Yoshida, Shigenobu; Watanabe, Takashi; Sameshima-Yamashita, Yuka; Nakajima-Kambe, Toshiaki; Tsushima, Seiya

2011-11-29

The use of biodegradable plastics can reduce the accumulation of environmentally persistent plastic wastes. The rate of degradation of biodegradable plastics depends on environmental conditions and is highly variable. Techniques for achieving more consistent degradation are needed. However, only a few microorganisms involved in the degradation process have been isolated so far from the environment. Here, we show that Pseudozyma spp. yeasts, which are common in the phyllosphere and are easily isolated from plant surfaces, displayed strong degradation activity on films made from poly-butylene succinate or poly-butylene succinate-co-adipate. Strains of P. antarctica isolated from leaves and husks of paddy rice displayed strong degradation activity on these films at 30°C. The type strain, P. antarctica JCM 10317, and Pseudozyma spp. strains from phyllosphere secreted a biodegradable plastic-degrading enzyme with a molecular mass of about 22 kDa. Reliable source of biodegradable plastic-degrading microorganisms are now in our hands.

Impact of landfill leachate on the groundwater quality: A case study in Egypt

PubMed Central

Abd El-Salam, Magda M.; I. Abu-Zuid, Gaber

2014-01-01

Alexandria Governorate contracted an international company in the field of municipal solid waste management for the collection, transport and disposal of municipal solid waste. Construction and operation of the sanitary landfill sites were also included in the contract for the safe final disposal of solid waste. To evaluate the environmental impacts associated with solid waste landfilling, leachate and groundwater quality near the landfills were analyzed. The results of physico-chemical analyses of leachate confirmed that its characteristics were highly variable with severe contamination of organics, salts and heavy metals. The BOD5/COD ratio (0.69) indicated that the leachate was biodegradable and un-stabilized. It was also found that groundwater in the vicinity of the landfills did not have severe contamination, although certain parameters exceeded the WHO and EPA limits. These parameters included conductivity, total dissolved solids, chlorides, sulfates, Mn and Fe. The results suggested the need for adjusting factors enhancing anaerobic biodegradation that lead to leachate stabilization in addition to continuous monitoring of the groundwater and leachate treatment processes. PMID:26199748

Impact of landfill leachate on the groundwater quality: A case study in Egypt.

PubMed

Abd El-Salam, Magda M; I Abu-Zuid, Gaber

2015-07-01

Alexandria Governorate contracted an international company in the field of municipal solid waste management for the collection, transport and disposal of municipal solid waste. Construction and operation of the sanitary landfill sites were also included in the contract for the safe final disposal of solid waste. To evaluate the environmental impacts associated with solid waste landfilling, leachate and groundwater quality near the landfills were analyzed. The results of physico-chemical analyses of leachate confirmed that its characteristics were highly variable with severe contamination of organics, salts and heavy metals. The BOD5/COD ratio (0.69) indicated that the leachate was biodegradable and un-stabilized. It was also found that groundwater in the vicinity of the landfills did not have severe contamination, although certain parameters exceeded the WHO and EPA limits. These parameters included conductivity, total dissolved solids, chlorides, sulfates, Mn and Fe. The results suggested the need for adjusting factors enhancing anaerobic biodegradation that lead to leachate stabilization in addition to continuous monitoring of the groundwater and leachate treatment processes.

Recent progress on biodegradable materials and transient electronics.

PubMed

Li, Rongfeng; Wang, Liu; Kong, Deying; Yin, Lan

2018-09-01

Transient electronics (or biodegradable electronics) is an emerging technology whose key characteristic is an ability to dissolve, resorb, or physically disappear in physiological environments in a controlled manner. Potential applications include eco-friendly sensors, temporary biomedical implants, and data-secure hardware. Biodegradable electronics built with water-soluble, biocompatible active and passive materials can provide multifunctional operations for diagnostic and therapeutic purposes, such as monitoring intracranial pressure, identifying neural networks, assisting wound healing process, etc. This review summarizes the up-to-date materials strategies, manufacturing schemes, and device layouts for biodegradable electronics, and the outlook is discussed at the end. It is expected that the translation of these materials and technologies into clinical settings could potentially provide vital tools that are beneficial for human healthcare.

Biodegradable and bio-based polymers: future prospects of eco-friendly plastics.

PubMed

Iwata, Tadahisa

2015-03-09

Currently used plastics are mostly produced from petrochemical products, but there is a growing demand for eco-friendly plastics. The use of bio-based plastics, which are produced from renewable resources, and biodegradable plastics, which are degraded in the environment, will lead to a more sustainable society and help us solve global environmental and waste management problems. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical, Thermal and Spectroscopic Methods to Assess Biodegradation of Winery-Distillery Wastes during Composting.

PubMed

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.

Chemical, Thermal and Spectroscopic Methods to Assess Biodegradation of Winery-Distillery Wastes during Composting

PubMed Central

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

Accelerated biodegradation of BPA in water-sediment microcosms with Bacillus sp. GZB and the associated bacterial community structure.

PubMed

Xiong, Jukun; An, Taicheng; Li, Guiying; Peng, Ping'an

2017-10-01

Bisphenol A (BPA) is a synthetic chemical primarily used to produce polycarbonate plastics and epoxy resins. Significant industrial and consumer's consumption of BPA-containing products has contributed to extensive contamination in different environmental matrices. In this study, microcosms bioaugmented with Bacillus sp. GZB were constructed to investigate BPA biodegradation, identify the main bacterial community, and evaluate bacterial community responses in the microcosms. Under aerobic conditions, BPA was quickly depleted as a result of bioaugmentation with Bacillus sp. GZB in water-sediment contaminated with pollutants. The pollutants used were generally associated with the electronic wastes (mobile phones, computers, televisions) dismantling process. Adding BPA affected the bacterial community composition in the water-sediment. Furthermore, BPA biodegradation was enhanced by adding electron donors/co-substrates: humic acid, NaCl, glucose, and yeast extract. Metagenomic analysis of the total 16S rRNA genes from the BPA-degrading microcosms with bioaugmentation illustrated that the genera Bacillus, Thiobacillus, Phenylobacterium, and Cloacibacterium were dominant after a 7-week incubation period. A consortium of microorganisms from different bacterial genera may be involved in BPA biodegradation in electronic waste contaminated water-sediment. This study provides new insights about BPA bioaugmentation and bacterial ecology in the BPA-degrading environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of a biosurfactant produced by Pseudomonas cepacia CCT6659 in the presence of industrial wastes and its application in the biodegradation of hydrophobic compounds in soil.

PubMed

Silva, Elias J; Rocha e Silva, Nathália Maria P; Rufino, Raquel D; Luna, Juliana M; Silva, Ricardo O; Sarubbo, Leonie A

2014-05-01

The bacterium Pseudomonas cepacia CCT6659 cultivated with 2% soybean waste frying oil and 2% corn steep liquor as substrates produced a biosurfactant with potential application in the bioremediation of soils. The biosurfactant was classified as an anionic biomolecule composed of 75% lipids and 25% carbohydrates. Characterization by proton nuclear magnetic resonance ((1)H and (13)C NMR) revealed the presence of carbonyl, olefinic and aliphatic groups, with typical spectra of lipids. Four sets of biodegradation experiments were carried out with soil contaminated by hydrophobic organic compounds amended with molasses in the presence of an indigenous consortium, as follows: Set 1-soil+bacterial cells; Set 2-soil+biosurfactant; Set 3-soil+bacterial cells+biosurfactant; and Set 4-soil without bacterial cells or biosurfactant (control). Significant oil biodegradation activity (83%) occurred in the first 10 days of the experiments when the biosurfactant and bacterial cells were used together (Set 3), while maximum degradation of the organic compounds (above 95%) was found in Sets 1-3 between 35 and 60 days. It is evident from the results that the biosurfactant alone and its producer species are both capable of promoting biodegradation to a large extent. Copyright © 2014 Elsevier B.V. All rights reserved.

Coliform Bacteria for Bioremediation of Waste Hydrocarbons

PubMed Central

2017-01-01

Raw, domestic sewage of Kuwait City contained about 106 ml−1 colony forming units of Enterobacter hormaechei subsp. oharae (56.6%), Klebsiella spp. (36%), and Escherichia coli (7.4%), as characterized by their 16S rRNA-gene sequences. The isolated coliforms grew successfully on a mineral medium with crude oil vapor as a sole source of carbon and energy. Those strains also grew, albeit to different degrees, on individual n-alkanes with carbon chains between C9 and C36 and on the individual aromatic hydrocarbons, toluene, naphthalene, phenanthrene, and biphenyl as sole sources of carbon and energy. These results imply that coliforms, like other hydrocarbonoclastic microorganisms, oxidize hydrocarbons to the corresponding alcohols and then to aldehydes and fatty acids which are biodegraded by β-oxidation to acetyl CoA. The latter is a well-known key intermediate in cell material and energy production. E. coli cells grown in the presence of n-hexadecane (but not in its absence) exhibited typical intracellular hydrocarbon inclusions, as revealed by transmission electron microscopy. Raw sewage samples amended with crude oil, n-hexadecane, or phenanthrene lost these hydrocarbons gradually with time. Meanwhile, the numbers of total and individual coliforms, particularly Enterobacter, increased. It was concluded that coliform bacteria in domestic sewage, probably in other environmental materials too, are effective hydrocarbon-biodegrading microorganisms. PMID:29082238

Microbial degradation of high impact polystyrene (HIPS), an e-plastic with decabromodiphenyl oxide and antimony trioxide.

PubMed

Sekhar, Vini C; Nampoothiri, K Madhavan; Mohan, Arya J; Nair, Nimisha R; Bhaskar, Thallada; Pandey, Ashok

2016-11-15

Accumulation of electronic waste has increased catastrophically and out of that various plastic resins constitute one of the leading thrown out materials in the electronic machinery. Enrichment medium, containing high impact polystyrene (HIPS) with decabromodiphenyl oxide and antimony trioxide as sole carbon source, was used to isolate microbial cultures. The viability of these cultures in the e-plastic containing mineral medium was further confirmed by triphenyl tetrazolium chloride (TTC) reduction test. Four cultures were identified by 16S rRNA sequencing as Enterobacter sp., Citrobacter sedlakii, Alcaligenes sp. and Brevundimonas diminuta. Biodegradation experiments were carried out in flask level and gelatin supplementation (0.1% w/v) along with HIPS had increased the degradation rate to a maximum of 12.4% (w/w) within 30days. This is the first report for this kind of material. The comparison of FTIR, NMR, and TGA analysis of original and degraded e-plastic films revealed structural changes under microbial treatment. Polystyrene degradation intermediates in the culture supernatant were also detected using HPLC analysis. The gravity of biodegradation was validated by morphological changes under scanning electron microscope. All isolates displayed depolymerase activity to substantiate enzymatic degradation of e-plastic. Copyright © 2016 Elsevier B.V. All rights reserved.

Natural Bioactive Compounds from Winery By-Products as Health Promoters: A Review

PubMed Central

Teixeira, Ana; Baenas, Nieves; Dominguez-Perles, Raul; Barros, Ana; Rosa, Eduardo; Moreno, Diego A.; Garcia-Viguera, Cristina

2014-01-01

The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health. PMID:25192288

Improving the 'tool box' for robust industrial enzymes.

PubMed

Littlechild, J A

2017-05-01

The speed of sequencing of microbial genomes and metagenomes is providing an ever increasing resource for the identification of new robust biocatalysts with industrial applications for many different aspects of industrial biotechnology. Using 'natures catalysts' provides a sustainable approach to chemical synthesis of fine chemicals, general chemicals such as surfactants and new consumer-based materials such as biodegradable plastics. This provides a sustainable and 'green chemistry' route to chemical synthesis which generates no toxic waste and is environmentally friendly. In addition, enzymes can play important roles in other applications such as carbon dioxide capture, breakdown of food and other waste streams to provide a route to the concept of a 'circular economy' where nothing is wasted. The use of improved bioinformatic approaches and the development of new rapid enzyme activity screening methodology can provide an endless resource for new robust industrial biocatalysts.This mini-review will discuss several recent case studies where industrial enzymes of 'high priority' have been identified and characterised. It will highlight specific hydrolase enzymes and recent case studies which have been carried out within our group in Exeter.

Anthropogenic impacts on the optical characteristics and biodegradability of dissolved and particulate organic matter in the Han River watershed, South Korea

NASA Astrophysics Data System (ADS)

Shirina Begum, Most; Jin, Hyojin; Yoon, Tae Kyung; Park, Ji-Hyung

2016-04-01

To understand how anthropogenic perturbations such as dams and pollution modify the chemical characteristics and biological transformations of riverine organic matter during transit through urbanized watersheds, we compared the optical characteristics and biodegradability of dissolved organic matter (DOM) and particulate organic matter (POM) along different reaches and urban tributary streams of the Han River watershed during short-term incubations. Laboratory incubations were conducted for 5-7 days at 20-25 oC with filtered or unfiltered water samples collected from up-, mid-, and downstream reaches with different levels of anthropogenic perturbations and three urban streams along the downstream reach that receive effluents from waste water treatment facilities in the metropolitan Seoul. Optical parameters such as ultraviolet absorbance at 254 nm, absorption coefficients at 254 nm and 350 nm, fluorescence index, humic-like fluorescence, microbial humic-like fluorescence, and protein-like fluorescence, and spectral slope at 350-400 nm were significantly correlated with increasing concentration of biodegradable dissolved organic carbon (BDOC) in filtered and unfiltered sample along the Han River up-, mid-, down-, and urban streams. The concentrations of BDOC in the urban streams were 6-12 times higher than in the filtered and unfiltered main-stem river samples, with significantly higher values in presence of POM in the unfiltered samples than in the filtered samples. In a separate 5-day incubation experiment with the unfiltered water sample from a downstream location of the Han River and its urban tributary water in isolation or mixed , the rate of concurrent biodegradation of both DOM and POM, as measured by the cumulative rate of CO2 production, was higher in the mixture than the average rate of the separately incubated samples, indicating the priming effect of mixed organic materials on the biodegradation of allochthonous organic materials from the other site. Greater amounts of CO2 were produced in all the samples than could be explained by BDOC alone, indicating the role of POM as a source of CO2. Faster and more intense changes in the consumed or produced components detected in the differential images between the fluorescence excitation emission matrices collected at intervals also suggested activated organic matter processing and CO2 production upon mixing the mainstem and tributary organic matter. Overall results suggest that dams and urban water pollution leave idiosyncratic imprints in the optical characteristics of DOM along waterways of the dammed and urbanized watershed and that inputs of anthropogenic organic materials via urban tributary streams can exert a strong priming effect on the biodegradation of both DOM and POM downstream.

Compostability assessment of nano-reinforced poly(lactic acid) films.

PubMed

Balaguer, M P; Aliaga, C; Fito, C; Hortal, M

2016-02-01

Nanomaterials can provide plastics with great advantages on mechanical and active properties (i.e. release and capture of specific substances). Therefore, packaging is expected to become one of the leading applications for these substances by 2020. There are some applications already in the market. Nevertheless, there is still some areas under development. A key issue to be analyzed is the end-of-life of these materials once they become waste, and specifically when nanomaterials are used in biodegradable products. The present study evaluated the disintegration, biodegradability, and ecotoxicity of poly(lactic acid) films reinforced with the three following nanomaterials: (1) montmorillonite modified with an ammonium quaternary salt, (2) calcium carbonate and (3) silicon dioxide. Results on disintegration showed that films completely disintegrated into visually indistinguishable residues after 6-7weeks of incubation in composting environment. Moreover, no differences were observed in the evolution of the bioresidue with respect to color, aspect, and odor in comparison with the control. It was also observed that nanomaterials did not significantly reduce the level of biodegradability of PLA (p>0.05). In fact, biodegradation was higher, without finding significant differences (p>0.05), in all the nano-reinforced samples with respect to PLA after 130days in composting (9.4% in PLA+Nano-SiO2; 34.0% in PLA+Clay1; 48.0% in PLA+Nano-CaCO3). Finally, no significant differences (p>0.05) in ecotoxicity in plants were observed as a result of the incorporation of nanoparticles in the PLA matrix. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microbial adaptation to biodegrade toxic organic micro-pollutants in membrane bioreactor using different sludge sources.

PubMed

Boonnorat, Jarungwit; Chiemchaisri, Chart; Chiemchaisri, Wilai; Yamamoto, Kazuo

2014-08-01

Biodegradation of toxic organic micro-pollutants in municipal solid waste (MSW) leachate by membrane bioreactor (MBR) was investigated. The MBR systems were seeded with different sludge sources, one was from a pilot-scale MBR system treating MSW leachate and the other was from an activated sludge sewage treatment plant. The biodegradation of BPA, 2,6-DTBP, BHT, DEP, DBP and DEHP, DCP and BBzP, by sludge from both reactors were found improved with time. However, enhanced biodegradation of micro-pollutants was observed in MBR operated under long sludge age condition. Bacterial population analyses determined by PCR-DGGE revealed the development of phenol and phthalate degrading bacteria consortium in MBR sludge during its operation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Abiotic and biotic degradation of oxo-biodegradable plastic bags by Pleurotus ostreatus.

PubMed

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Bazzolli, Denise Mara Soares; Tótola, Marcos Rogério; Demuner, Antônio Jacinto; Kasuya, Maria Catarina Megumi

2014-01-01

In this study, we evaluated the growth of Pleurotus ostreatus PLO6 using oxo-biodegradable plastics as a carbon and energy source. Oxo-biodegradable polymers contain pro-oxidants that accelerate their physical and biological degradation. These polymers were developed to decrease the accumulation of plastic waste in landfills. To study the degradation of the plastic polymers, oxo-biodegradable plastic bags were exposed to sunlight for up to 120 days, and fragments of these bags were used as substrates for P. ostreatus. We observed that physical treatment alone was not sufficient to initiate degradation. Instead, mechanical modifications and reduced titanium oxide (TiO2) concentrations caused by sunlight exposure triggered microbial degradation. The low specificity of lignocellulolytic enzymes and presence of endomycotic nitrogen-fixing microorganisms were also contributing factors in this process.

[Biodegradability of the components of natural hydrocarbon mixtures previously submitted to landfarming].

PubMed

Pucci, G N; Pucci, O H

2003-01-01

The complex composition of the crude oil and the hydrocarbons that integrate the waste of the different stages of the oil industry turn this product a mixture that presents different difficulties for its elimination by biological methods. The objective of this paper was to study the biodegradation potential of autochthonous bacterial communities on hydrocarbons obtained from four polluted places and subjected to landfarming biorremediation system during a decade. The results showed a marked difference in biodegradability of the three main fractions of crude oil, aliphatic, aromatic, and polar fractions, obtained by column chromatography. All fractions were used as carbon source and energy. There were variations in the production of biomass among the different fractions as well as in the kinetics of biodegradation, according to the composition of each fraction.

Behavior of an MBT waste in monotonic triaxial shear tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhandari, Athma Ram, E-mail: athma.bhandari@beg.utexas.edu; Powrie, William, E-mail: w.powrie@soton.ac.uk

2013-04-15

Highlights: ► We studied the stress–strain–strength characteristics of an MBT waste. ► Rate of mobilization of strength with strain depends on initial density. ► Image analysis technique was used to determine whole-specimen displacement fields. ► Initial mode of deformation of a loose specimen is one-dimensional compression. ► Reinforcing elements enhance the resistance to lateral and volumetric deformation. - Abstract: Legislation in some parts of the world now requires municipal solid waste (MSW) to be processed prior to landfilling to reduce its biodegradability and hence its polluting potential through leachate and fugitive emission of greenhouse gases. This pre-processing may be achievedmore » through what is generically termed mechanical–biological-treatment (MBT). One of the major concerns relating to MBT wastes is that the strength of the material may be less than for raw MSW, owing to the removal of sheet, stick and string-like reinforcing elements during processing. Also, the gradual increase in mobilized strength over strains of 30% or so commonly associated with unprocessed municipal solid waste may not occur with treated wastes. This paper describes a series of triaxial tests carried out to investigate the stress–strain–strength characteristics of an MBT waste, using a novel digital image analysis technique for the determination of detailed displacement fields over the whole specimen. New insights gained into the mechanical behavior of MBT waste include the effect of density on the stress–strain response, the initial 1-D compression of lightly consolidated specimens, and the likely reinforcing effect of small sheet like particles remaining in the waste.« less

Biodegradable Polymeric Materials in Degradable Electronic Devices

PubMed Central

2018-01-01

Biodegradable electronics have great potential to reduce the environmental footprint of devices and enable advanced health monitoring and therapeutic technologies. Complex biodegradable electronics require biodegradable substrates, insulators, conductors, and semiconductors, all of which comprise the fundamental building blocks of devices. This review will survey recent trends in the strategies used to fabricate biodegradable forms of each of these components. Polymers that can disintegrate without full chemical breakdown (type I), as well as those that can be recycled into monomeric and oligomeric building blocks (type II), will be discussed. Type I degradation is typically achieved with engineering and material science based strategies, whereas type II degradation often requires deliberate synthetic approaches. Notably, unconventional degradable linkages capable of maintaining long-range conjugation have been relatively unexplored, yet may enable fully biodegradable conductors and semiconductors with uncompromised electrical properties. While substantial progress has been made in developing degradable device components, the electrical and mechanical properties of these materials must be improved before fully degradable complex electronics can be realized. PMID:29632879

Biodegradable Shape Memory Polymers in Medicine.

PubMed

Peterson, Gregory I; Dobrynin, Andrey V; Becker, Matthew L

2017-11-01

Shape memory materials have emerged as an important class of materials in medicine due to their ability to change shape in response to a specific stimulus, enabling the simplification of medical procedures, use of minimally invasive techniques, and access to new treatment modalities. Shape memory polymers, in particular, are well suited for such applications given their excellent shape memory performance, tunable materials properties, minimal toxicity, and potential for biodegradation and resorption. This review provides an overview of biodegradable shape memory polymers that have been used in medical applications. The majority of biodegradable shape memory polymers are based on thermally responsive polyesters or polymers that contain hydrolyzable ester linkages. These materials have been targeted for use in applications pertaining to embolization, drug delivery, stents, tissue engineering, and wound closure. The development of biodegradable shape memory polymers with unique properties or responsiveness to novel stimuli has the potential to facilitate the optimization and development of new medical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Soil Quality and Colloid Transport under Biodegradable Mulches

NASA Astrophysics Data System (ADS)

Sintim, Henry; Bandopadhyay, Sreejata; Ghimire, Shuresh; Flury, Markus; Bary, Andy; Schaeffer, Sean; DeBruyn, Jennifer; Miles, Carol; Inglis, Debra

2016-04-01

Polyethylene (PE) mulch is commonly used in agriculture to increase water use efficiency, to control weeds, manage plant diseases, and maintain a favorable micro-climate for plant growth. However, producers need to retrieve and safely dispose PE mulch after usage, which creates enormous amounts of plastic waste. Substituting PE mulch with biodegradable plastic mulches could alleviate disposal needs. However, repeated applications of biodegradable mulches, which are incorporated into the soil after the growing season, may cause deterioration of soil quality through breakdown of mulches into colloidal fragments, which can be transported through soil. Findings from year 1 of a 5-year field experiment will be presented.

Biodegradation of waste lubricants by a newly isolated Ochrobactrum sp. C1.

PubMed

Bhattacharya, Munna; Biswas, Dipa; Sana, Santanu; Datta, Sriparna

2015-10-01

A potential degrader of paraffinic and aromatic hydrocarbons was isolated from oil-contaminated soil from steel plant effluent area in Burnpur, India. The strain was investigated for degradation of waste lubricants (waste engine oil and waste transformer oil) that often contain EPA (Environmental Protection Agency, USA) classified priority pollutants and was identified as Ochrobactrum sp. C1 by 16S rRNA gene sequencing. The strain C1 was found to tolerate unusually high waste lubricant concentration along with emulsification capability of the culture broth, and its degradation efficiency was 48.5 ± 0.5 % for waste engine oil and 30.47 ± 0.25 % for waste transformer oil during 7 days incubation period. In order to get optimal degradation efficiency, a three level Box-Behnken design was employed to optimize the physical parameters namely pH, temperature and waste oil concentration. The results indicate that at temperature 36.4 °C, pH 7.3 and with 4.6 % (v/v) oil concentration, the percentage degradation of waste engine oil will be 57 % within 7 days. At this optimized condition, the experimental values (56.7 ± 0.25 %) are in a good agreement with the predicted values with a calculated R 2 to be 0.998 and significant correlation between biodegradation and emulsification activity (E 24  = 69.42 ± 0.32 %) of the culture broth toward engine oil was found with a correlation coefficient of 0.972. This is the first study showing that an Ochrobactrum sp. strain is capable of degrading waste lubricants, which might contribute to the bioremediation of waste lubricating oil-contaminated soil.

Fast Breaking Detergents: Their Role in the Generation of Hydrogen Sulfide in Oily-Water Wastes

DTIC Science & Technology

1993-09-01

central fission would retard the biodegradation of this surfactant under anaerobic conditions. In "Ameroid", the surfactant is an m- alkylphenol ...and glycolic acid) will be small. After E-Chain metabolism is complete, an alkylphenol residue accumulates which has been observed to inhibit further...during the initial biodegradation of the surfactant ( alkylphenols ). Since the "Ameroid" results in these trials were inconsistent, any variations can not

Optimizing edible fungal growth and biodegradation of inedible crop residues using various cropping methods.

PubMed

Nyochembeng, Leopold M; Beyl, Caula A; Pacumbaba, R P

2008-09-01

Long-term manned space flights to Mars require the development of an advanced life support (ALS) ecosystem including efficient food crop production, processing and recycling waste products thereof. Using edible white rot fungi (EWRF) to achieve effective biomass transformation in ALS requires optimal and rapid biodegradative activity on lignocellulosic wastes. We investigated the mycelial growth of Lentinula edodes and Pleurotus ostreatus on processed residues of various crops under various cropping patterns. In single cropping, mycelial growth and fruiting in all strains were significantly repressed on sweet potato and basil. However, growth of the strains was improved when sweet potato and basil residues were paired with rice or wheat straw. Oyster mushroom (Pleurotus) strains were better than shiitake (L. edodes) strains under single, paired, and mixed cropping patterns. Mixed cropping further eliminated the inherent inhibitory effect of sweet potato, basil, or lettuce on fungal growth. Co-cropping fungal species had a synergistic effect on rate of fungal growth, substrate colonization, and fruiting. Use of efficient cropping methods may enhance fungal growth, fruiting, biodegradation of crop residues, and efficiency of biomass recycling.

Engineering a more sustainable world through catalysis and green chemistry.

PubMed

Sheldon, Roger A

2016-03-01

The grand challenge facing the chemical and allied industries in the twenty-first century is the transition to greener, more sustainable manufacturing processes that efficiently use raw materials, eliminate waste and avoid the use of toxic and hazardous materials. It requires a paradigm shift from traditional concepts of process efficiency, focusing on chemical yield, to one that assigns economic value to replacing fossil resources with renewable raw materials, eliminating waste and avoiding the use of toxic and/or hazardous substances. The need for a greening of chemicals manufacture is readily apparent from a consideration of the amounts of waste generated per kilogram of product (the E factors) in various segments of the chemical industry. A primary source of this waste is the use of antiquated 'stoichiometric' technologies and a major challenge is to develop green, catalytic alternatives. Another grand challenge for the twenty-first century, driven by the pressing need for climate change mitigation, is the transition from an unsustainable economy based on fossil resources--oil, coal and natural gas--to a sustainable one based on renewable biomass. In this context, the valorization of waste biomass, which is currently incinerated or goes to landfill, is particularly attractive. The bio-based economy involves cross-disciplinary research at the interface of biotechnology and chemical engineering, focusing on the development of green, chemo- and biocatalytic technologies for waste biomass conversion to biofuels, chemicals and bio-based materials. Biocatalysis has many benefits to offer in this respect. The catalyst is derived from renewable biomass and is biodegradable. Processes are performed under mild conditions and generally produce less waste and are more energy efficient than conventional ones. Thanks to modern advances in biotechnology 'tailor-made' enzymes can be economically produced on a large scale. However, for economic viability it is generally necessary to recover and re-use the enzyme and this can be achieved by immobilization, e.g. as solid cross-linked enzyme aggregates (CLEAs), enabling separation by filtration or centrifugation. A recent advance is the use of 'smart', magnetic CLEAs, which can be separated magnetically from reaction mixtures containing suspensions of solids; truly an example of cross-disciplinary research at the interface of physical and life sciences, which is particularly relevant to biomass conversion processes. © 2016 The Author(s).

Engineering a more sustainable world through catalysis and green chemistry

PubMed Central

2016-01-01

The grand challenge facing the chemical and allied industries in the twenty-first century is the transition to greener, more sustainable manufacturing processes that efficiently use raw materials, eliminate waste and avoid the use of toxic and hazardous materials. It requires a paradigm shift from traditional concepts of process efficiency, focusing on chemical yield, to one that assigns economic value to replacing fossil resources with renewable raw materials, eliminating waste and avoiding the use of toxic and/or hazardous substances. The need for a greening of chemicals manufacture is readily apparent from a consideration of the amounts of waste generated per kilogram of product (the E factors) in various segments of the chemical industry. A primary source of this waste is the use of antiquated ‘stoichiometric’ technologies and a major challenge is to develop green, catalytic alternatives. Another grand challenge for the twenty-first century, driven by the pressing need for climate change mitigation, is the transition from an unsustainable economy based on fossil resources—oil, coal and natural gas—to a sustainable one based on renewable biomass. In this context, the valorization of waste biomass, which is currently incinerated or goes to landfill, is particularly attractive. The bio-based economy involves cross-disciplinary research at the interface of biotechnology and chemical engineering, focusing on the development of green, chemo- and biocatalytic technologies for waste biomass conversion to biofuels, chemicals and bio-based materials. Biocatalysis has many benefits to offer in this respect. The catalyst is derived from renewable biomass and is biodegradable. Processes are performed under mild conditions and generally produce less waste and are more energy efficient than conventional ones. Thanks to modern advances in biotechnology ‘tailor-made’ enzymes can be economically produced on a large scale. However, for economic viability it is generally necessary to recover and re-use the enzyme and this can be achieved by immobilization, e.g. as solid cross-linked enzyme aggregates (CLEAs), enabling separation by filtration or centrifugation. A recent advance is the use of ‘smart’, magnetic CLEAs, which can be separated magnetically from reaction mixtures containing suspensions of solids; truly an example of cross-disciplinary research at the interface of physical and life sciences, which is particularly relevant to biomass conversion processes. PMID:27009181

Phenol Biodegradation by Free and Immobilized Candida tropicalis RETL-Crl on Coconut Husk and Loofah Packed in Biofilter Column

NASA Astrophysics Data System (ADS)

Shazryenna, D.; Ruzanna, R.; Jessica, M. S.; Piakong, M. T.

2015-04-01

Phenols and its derivatives are environmental pollutant commonly found in many industrial effluents. It is toxic in nature and causes various health hazards. However, they are poorly removed in conventional biological processes due to their toxicity. Immobilization of microbial cells has received increasing interest in the field of waste treatment and creates opportunities in a wide range of sectors including environmental pollution control. Live cells of phenol-degrading yeast, Candida tropicalis RETL-Crl, were immobilized on coconut husk and loofah by adsorption. The immobolized particle was packed into biofilter column which used for continuous treatment of a phenol with initial phenol concentration of 3mM. Both loofah and coconut husk have similar phenol biodegradation rate of 0.0188 gL-1h-1 within 15 hours to achieve a phenol removal efficiency of 100%. However loofah have lower biomass concentration of 4.22 gL-1 compared to biomass concentration on coconut husk, 4.39 gL-1. Coconut husk contain higher biomass concentration which makes it better support material than loofah. Fibrous matrices such as loofah and coconut husk provide adequate supporting surfaces for cell adsorption, due to their high specific surface area. Therefore, coconut husk and loofah being an agricultural waste product have the potential to be used as low-cost adsorbent and support matrix for microbial culture immobilization for the removal of organic pollutant from wastewater.

Combining Nitrilotriacetic Acid and Permeable Barriers for Enhanced Phytoextraction of Heavy Metals from Municipal Solid Waste Compost by and Reduced Metal Leaching.

PubMed

Zhao, Shulan; Jia, Lina; Duo, Lian

2016-05-01

Phytoextraction has the potential to remove heavy metals from contaminated soil, and chelants can be used to improve the capabilities of phytoextraction. However, environmentally persistent chelants can cause metal leaching and groundwater pollution. A column experiment was conducted to evaluate the viability of biodegradable nitrilotriacetic acid (NTA) to increase the uptake of heavy metals (Cd, Cr, Ni, Pb, Cu, and Zn) by L. in municipal solid waste (MSW) compost and to evaluate the effect of two permeable barrier materials, bone meal and crab shell, on metal leaching. The application of NTA significantly increased the concentrations and uptake of heavy metals in . The enhancement was more pronounced at higher dosages of NTA. In the 15 mmol kg NTA treatment using a crab shell barrier, the Cr and Ni concentrations in the plant shoots increased by approximately 8- and 10-fold, respectively, relative to the control. However, the addition of NTA also caused significant heavy metal leaching from the MSW compost. Bone meal and crab shell barriers positioned between the compost and the subsoil were effective in preventing metal leaching down through the soil profile by the retention of metals in the barrier. The application of a biodegradable chelant and the use of permeable barriers is a viable form of enhanced phytoextraction to increase the removal of metals and to reduce possible leaching. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

A cellulose fiber-based diet for screwworm (Diptera: Calliphoridae) larvae.

PubMed

Chaudhury, M F; Skoda, S R

2007-02-01

A highly absorbent cellulose fiber from recycled paper was tested and compared with a polyacrylate gelling agent, Aquatain, normally used for bulking and solidifying larval rearing medium of screwworm, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae). The absorbent fiber, when mixed with water and dietary ingredients, produced a diet medium of homogeneous texture that supported larval growth and development comparable with the standard gelled diet. Larval and pupal weights from two concentrations of cellulose fiber-based diet were significantly higher than those obtained using gelled diet. The number of pupae per tray, percentage of adult emergence, oviposition, percentage of egg hatch, and adult longevity obtained from the insects reared in the cellulose fiber-based diet were comparable or slightly better than the biological parameters recorded from flies reared in the gelled diet. Moreover, results indicate that a lesser amount of the cellulose fiber-based diet than the normal amount of gelled diet per tray would support normal larval growth. Physical properties and texture of the new diet seem to allow the larvae to move and feed more freely than they do on the semisolid gelled diet, resulting in less wasted diet. The cellulose fiber is biodegradable and inexpensive, whereas the polyacrylate gel polymer is not biodegradable and is relatively expensive. Replacing gel with cellulose fiber in the screwworm larval diet for mass rearing should result in substantial cost savings in material and labor as well as eliminating concern of environmental pollution due to diet waste disposal.

Exploring anaerobic environments for cyanide and cyano-derivatives microbial degradation.

PubMed

Luque-Almagro, Víctor M; Cabello, Purificación; Sáez, Lara P; Olaya-Abril, Alfonso; Moreno-Vivián, Conrado; Roldán, María Dolores

2018-02-01

Cyanide is one of the most toxic chemicals for living organisms described so far. Its toxicity is mainly based on the high affinity that cyanide presents toward metals, provoking inhibition of essential metalloenzymes. Cyanide and its cyano-derivatives are produced in a large scale by many industrial activities related to recovering of precious metals in mining and jewelry, coke production, steel hardening, synthesis of organic chemicals, and food processing industries. As consequence, cyanide-containing wastes are accumulated in the environment becoming a risk to human health and ecosystems. Cyanide and related compounds, like nitriles and thiocyanate, are degraded aerobically by numerous bacteria, and therefore, biodegradation has been offered as a clean and cheap strategy to deal with these industrial wastes. Anaerobic biological treatments are often preferred options for wastewater biodegradation. However, at present very little is known about anaerobic degradation of these hazardous compounds. This review is focused on microbial degradation of cyanide and related compounds under anaerobiosis, exploring their potential application in bioremediation of industrial cyanide-containing wastes.

The degradability of biodegradable plastics in aerobic and anaerobic waste landfill model reactors.

PubMed

Ishigaki, Tomonori; Sugano, Wataru; Nakanishi, Akane; Tateda, Masafumi; Ike, Michihiko; Fujita, Masanori

2004-01-01

Degradabilities of four kinds of commercial biodegradable plastics (BPs), polyhydroxybutyrate and hydroxyvalerate (PHBV) plastic, polycaprolactone plastic (PCL), blend of starch and polyvinyl alcohol (SPVA) plastic and cellulose acetate (CA) plastic were investigated in waste landfill model reactors that were operated as anaerobically and aerobically. The application of forced aeration to the landfill reactor for supplying aerobic condition could potentially stimulate polymer-degrading microorganisms. However, the individual degradation behavior of BPs under the aerobic condition was completely different. PCL, a chemically synthesized BP, showed film breakage under the both conditions, which may have contributed to a reduction in the waste volume regardless of aerobic or anaerobic conditions. Effective degradation of PHBV plastic was observed in the aerobic condition, though insufficient degradation was observed in the anaerobic condition. But the aeration did not contribute much to accelerate the volume reduction of SPVA plastic and CA plastic. It could be said that the recalcitrant portions of the plastics such as polyvinyl alcohol in SPVA plastic and the highly substituted CA in CA plastic prevented the BP from degradation. These results indicated existence of the great variations in the degradability of BPs in aerobic and anaerobic waste landfills, and suggest that suitable technologies for managing the waste landfill must be combined with utilization of BPs in order to enhance the reduction of waste volume in landfill sites.

Biodegradability and plasticizing effect of yerba mate extract on cassava starch edible films.

PubMed

Medina Jaramillo, Carolina; Gutiérrez, Tomy J; Goyanes, Silvia; Bernal, Celina; Famá, Lucía

2016-10-20

Biodegradable and edible cassava starch-glycerol based films with different concentrations of yerba mate extract (0, 5 and 20wt.%) were prepared by casting. The plasticizing effect of yerba mate extract when it was incorporated into the matrix as an antioxidant was investigated. Thermal degradation and biodegradability of the obtained biofilms were also studied. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FTIR), X-ray diffraction analysis (XRD), water absorbance, stability in different solutions and biodegradability studies were performed. The clear correlation among the results obtained from the different analysis confirmed the plasticizing effect of yerba mate extract on the starch-glycerol matrix. Also, the extract led to a decrease in the degradation time of the films in soil ensuring their complete biodegradability before two weeks and to films stability in acidic and alkaline media. The plasticizing effect of yerba mate extract makes it an attractive additive for starch films which will be used as packaging or coating; and its contribution to an earlier biodegradability will contribute to waste reduction. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pelleted organo-mineral fertilisers from composted pig slurry solids, animal wastes and spent mushroom compost for amenity grasslands.

PubMed

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.

High solids co-digestion of food and landscape waste and the potential for ammonia toxicity.

PubMed

Drennan, Margaret F; DiStefano, Thomas D

2014-07-01

A pilot-scale study was completed to determine the feasibility of high-solids anaerobic digestion (HSAD) of a mixture of food and landscape wastes at a university in central Pennsylvania (USA). HSAD was stable at low loadings (2g COD/L-day), but developed inhibitory ammonia concentrations at high loadings (15 g COD/L-day). At low loadings, methane yields were 232 L CH4/kg COD fed and 229 L CH4/kg VS fed, and at high loadings yields were 211 L CH4/kg COD fed and 272 L CH4/kg VS fed. Based on characterization and biodegradability studies, food waste appears to be a good candidate for HSAD at low organic loading rates; however, the development of ammonia inhibition at high loading rates suggests that the C:N ratio is too low for use as a single substrate. The relatively low biodegradability of landscape waste as reported herein made it an unsuitable substrate to increase the C:N ratio. Codigestion of food waste with a substrate high in bioavailable carbon is recommended to increase the C:N ratio sufficiently to allow HSAD at loading rates of 15 g COD/L-day. Copyright © 2014 Elsevier Ltd. All rights reserved.

ETHANOL BIODEGRADATION FROM GASOLINE RELEASES AND ITS EFFECT ON BTEX BIODEGRADATIONS

EPA Science Inventory

How fast will ethanol biodegrade and what impact will it have on the biodegradation of BTEX in a gasoline spill? This session will provide evidence to answer these questions based on laboratory data. Material from UST spills from Long Island, New York, New Jersey, Florida, and ...

Influence of alternative electron acceptors on the anaerobic biodegradability of chlorinated phenols and benzoic acids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haeggblom, M.M.; Rivera, M.D.; Young, L.Y.

1993-04-01

Methanogeneic conditions can promote the biodegradation of a number of halogenated aromatic compounds. This study, using sediments from freshwater and estuarine sites, is an evaluation of the anaerobic biodegradability of monochlorinated phenols and benzoic acids coupled to denitrification, sulfidogenesis, and methanogenesis. The results indicate that chlorinated phenols and benzoic acids are biodegradable under at least one set of anaerobic conditions. Metabolism depends both on the electron acceptor available and on the position of the chlorine substituent. Presence of alternative electron acceptors, nitrate, sulfate, and carbonate, can affect degradation rates and substrate specificities. Since contaminated sites usually have mixtures of wastes,more » bioremediation efforts may need to consider the activities of diverse anaerobic communities to carry out effective treatment of all components. 37 refs., 4 figs., 4 tabs.« less

Abiotic and Biotic Degradation of Oxo-Biodegradable Plastic Bags by Pleurotus ostreatus

PubMed Central

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Bazzolli, Denise Mara Soares; Tótola, Marcos Rogério; Demuner, Antônio Jacinto; Kasuya, Maria Catarina Megumi

2014-01-01

In this study, we evaluated the growth of Pleurotus ostreatus PLO6 using oxo-biodegradable plastics as a carbon and energy source. Oxo-biodegradable polymers contain pro-oxidants that accelerate their physical and biological degradation. These polymers were developed to decrease the accumulation of plastic waste in landfills. To study the degradation of the plastic polymers, oxo-biodegradable plastic bags were exposed to sunlight for up to 120 days, and fragments of these bags were used as substrates for P. ostreatus. We observed that physical treatment alone was not sufficient to initiate degradation. Instead, mechanical modifications and reduced titanium oxide (TiO2) concentrations caused by sunlight exposure triggered microbial degradation. The low specificity of lignocellulolytic enzymes and presence of endomycotic nitrogen-fixing microorganisms were also contributing factors in this process. PMID:25419675

Peering into the secrets of food and agricultural co-products

NASA Astrophysics Data System (ADS)

Wood, Delilah; Williams, Tina; Glenn, Gregory; Pan, Zhongli; Orts, William; McHugh, Tara

2010-06-01

Scanning electron microscopy is a useful tool for understanding food contamination and directing product development of food and industrial products. The current trend in food research is to produce foods that are fast to prepare and/or ready to eat. At the same time, these processed foods must be safe, high quality and maintain all or most of the nutritional value of the original whole foods. Minimally processed foods, is the phrase used to characterize these "new" foods. New techniques are needed which take advantage of minimal processing or processing which enhances the fresh properties and characteristics of whole foods while spending less time on food preparation. The added benefit coupled to less cooking time in an individual kitchen translates to an overall energy savings and reduces the carbon emissions to the environment. Food processing changes the microstructure, and therefore, the quality, texture and flavor, of the resulting food product. Additionally, there is the need to reduce waste, transportation costs and product loss during transportation and storage. Unlike food processing, structural changes are desirable in co-products as function follows form for food packaging films and boxes as well as for building materials and other industrial products. Thus, the standard materials testing procedures are coupled with SEM to provide direction in the development of products from agricultural residues or what would otherwise be considered waste materials. The use of agricultural residues reduces waste and adds value to a currently underutilized or unutilized product. The product might be biodegradable or compostable, thus reducing landfill requirements. Manufacturing industrial and packaging products from biological materials also reduces the amount of petroleum products currently standard in the industry.

Compositional and moisture content effects on the biodegradability of zein/ethylcellulose films.

PubMed

Romero-Bastida, Claudia A; Flores-Huicochea, Eduardo; Martin-Polo, Martha O; Velazquez, Gonzalo; Torres, J Antonio

2004-04-21

The effect of moisture content and film composition on biodegradability is the focus of this study. Flexible films were first characterized for the effect on water sorption isotherms of relative humidity, temperature, zein content, and the addition of the plasticizers stearic acid, poly(ethylene glycol), or etoxylated ricine oil. Zein/ethylcellulose (EC) mixture films had a behavior between that for pure zein and EC films, which had the lowest water sorption. For films with plasticizer, the lowest water sorption at 25 degrees C was observed for those with stearic acid. Biodegradability of zein/EC films, evaluated using bacterial cultures selected for their zein proteolytic activity and isolated from a local solid waste landfill and a lagoon, showed no plasticizer effect even though its effect on moisture content was significant. Large differences were observed at different film zein concentration with the highest biodegradability for 100% zein. However, biodegradability did not mimic the water sorption behavior of zein/EC mixture films.

Platelet adhesion and human umbilical vein endothelial cell cytocompatibility of biodegradable segmented polyurethanes prepared with 4,4'-methylene bis(cyclohexyl isocyanate), poly(caprolactone) diol and butanediol or dithioerythritol as chain extenders.

PubMed

Chan-Chan, L H; Vargas-Coronado, R F; Cervantes-Uc, J M; Cauich-Rodríguez, J V; Rath, R; Phelps, E A; García, A J; San Román Del Barrio, J; Parra, J; Merhi, Y; Tabrizian, M

2013-08-01

Biodegradable segmented polyurethanes were prepared with poly(caprolactone) diol as a soft segment, 4,4'-methylene bis(cyclohexyl isocyanate) (HMDI) and either butanediol or dithioerythritol as chain extenders. Platelet adhesion was similar in all segmented polyurethanes studied and not different from Tecoflex® although an early stage of activation was observed on biodegradable segmented polyurethane prepared with dithioerythritol. Relative viability was higher than 80% on human umbilical vein endothelial cells in contact with biodegradable segmented polyurethane extracts after 1, 2 and 7 days. Furthermore, both biodegradable segmented polyurethane materials supported human umbilical vein endothelial cell adhesion, spreading, and viability similar to Tecoflex® medical-grade polyurethane. These biodegradable segmented polyurethanes represent promising materials for cardiovascular applications.

Here today, gone tomorrow: biodegradable soft robots

NASA Astrophysics Data System (ADS)

Rossiter, Jonathan; Winfield, Jonathan; Ieropoulos, Ioannis

2016-04-01

One of the greatest challenges to modern technologies is what to do with them when they go irreparably wrong or come to the end of their productive lives. The convention, since the development of modern civilisation, is to discard a broken item and then procure a new one. In the 20th century enlightened environmentalists campaigned for recycling and reuse (R and R). R and R has continued to be an important part of new technology development, but there is still a huge problem of non-recyclable materials being dumped into landfill and being discarded in the environment. The challenge is even greater for robotics, a field which will impact on all aspects of our lives, where discards include motors, rigid elements and toxic power supplies and batteries. One novel solution is the biodegradable robot, an active physical machine that is composed of biodegradable materials and which degrades to nothing when released into the environment. In this paper we examine the potential and realities of biodegradable robotics, consider novel solutions to core components such as sensors, actuators and energy scavenging, and give examples of biodegradable robotics fabricated from everyday, and not so common, biodegradable electroactive materials. The realisation of truly biodegradable robots also brings entirely new deployment, exploration and bio-remediation capabilities: why track and recover a few large non-biodegradable robots when you could speculatively release millions of biodegradable robots instead? We will consider some of these exciting developments and explore the future of this new field.

Biofuel from "humified" biomass

NASA Astrophysics Data System (ADS)

Kpogbemabou, D.; Lemée, L.; Amblès, A.

2009-04-01

In France, 26% of the emissions of greenhouse effect gas originate from transportation which depends for 87% on fossil fuels. Nevertheless biofuels can contribute to the fight against climate change while reducing energetic dependence. Indeed biomass potentially represents in France 30 Mtoe a year that is to say 15% national consumption. But 80% of these resources are made of lignocellulosic materials which are hardly exploitable. First-generation biofuels are made from sugar, starch, vegetable oil, or animal fats. Due to their competition with human food chain, first-generation biofuels could lead to food shortages and price rises. At the contrary second-generation biofuel production can use a variety of non food crops while using the lignocellulosic part of biomass [1]. Gasification, fermentation and direct pyrolysis are the most used processes. However weak yields and high hydrogen need are limiting factors. In France, the National Program for Research on Biofuels (PNRB) aims to increase mobilizable biomass resource and to develop lignocellulosic biomass conversion. In this context, the LIGNOCARB project studies the liquefaction of biodegraded biomass in order to lower hydrogen consumption. Our aim was to develop and optimize the biodegradation of the biomass. Once the reactor was achieved, the influence of different parameters (starting material, aeration, moisture content) on the biotransformation process was studied. The monitored parameters were temperature, pH and carbon /nitrogen ratio. Chemical (IHSS protocol) and biochemical (van Soest) fractionations were used to follow the maturity ("humic acid"/"fulvic acid" ratio) and the biological stability (soluble, hemicelluloses, celluloses, lignin) of the organic matter (OM). In example, the increase in lignin can be related to the stabilization since the OM becomes refractory to biodegradation whereas the increase in the AH/AF ratio traduces "humification". However, contrarily to the composting process, we do not look forward to obtain a mature OM for which the carbon loss would be too important. The global analysis of the biomass OM during biodegradation using infrared spectroscopy (DRIFTS) confirms "humification". Indeed the relative intensity of bands associated to aromatics increase relatively to those associated to aliphatics[2] [3]. The molecular study of lipids and humic fractions was realised using mass spectrometry (GC/MS), pyrolysis (Py-GC/MS) and thermodesorption (Headspace-GC/MS). The decrease in lipids indicates a high biodegradation. Amongst volatile organic compounds (COVs), the isoprenoid C18 ketone which is probably produced from biodegradation of phytol is observed in all our samples. The organic matter obtained after biodegradation is stable (resistant to biodegradation) and humified but still rich in carbon. The characterisation of bacterial biomarkers will help us to specify and thus to optimize biotransformation mechanisms. [1] A. Dermirbas and Al, Progress in energy and combustion science, 33 (2007), 1 - 18. [2] P. Castaldi and Al, Waste Management, 25 (2005), 213 - 217. [3] Mr. Crube and Al, Geoderma, 130 2006, 1573 - 1586.

Hydro-mechanical behavior of Municipal Solid Waste subject to leachate recirculation in a large-scale compression reactor cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olivier, Franck; Gourc, Jean-Pierre

2007-07-01

The paper presents the results of a laboratory experiment on Municipal Solid Waste (MSW) subjected to one-dimensional compression in a 1 m{sup 3} instrumented cell. The focus was on the hydro-mechanical behavior of the material under conditions of confinement and leachate percolation that replicate those found in real-scale landfills. The operation of the apparatus is detailed together with the testing methodology and the monitoring program. Two samples of waste were tested: the first extended over a period of 10 months ('Control Test') and the second for 22 months ('Enhanced Test' with leachate recirculation). Consolidation data is reported with regard tomore » both short-term (stress-dependent) and long-term (time-dependent) settlements. A discussion follows based on the derived values of primary and secondary compression ratios. Correlations between compression parameters and the biodegradation process are presented. In particular, results clearly highlight the effect of leachate recirculation on waste settlement: 24% secondary deformation reached after slightly less than 2 years (equivalent to a 5-fold increase in compressibility) and 17.9% loss of dry matter. Comparisons are proposed considering the results derived from the few monitoring programs conducted on experimental bioreactors worldwide. Finally, the hydraulic characterization of waste is discussed with regard to the evaluation of effective porosity and permeability.« less

Biodegradable Orthopedic Magnesium-Calcium (MgCa) Alloys, Processing, and Corrosion Performance.

PubMed

Salahshoor, Meisam; Guo, Yuebin

2012-01-09

Magnesium-Calcium (Mg-Ca) alloy has received considerable attention as an emerging biodegradable implant material in orthopedic fixation applications. The biodegradable Mg-Ca alloys avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. They also provide sufficient mechanical strength in load carrying applications as opposed to biopolymers. However, the key issue facing a biodegradable Mg-Ca implant is the fast corrosion in the human body environment. The ability to adjust degradation rate of Mg-Ca alloys is critical for the successful development of biodegradable orthopedic implants. This paper focuses on the functions and requirements of bone implants and critical issues of current implant biomaterials. Microstructures and mechanical properties of Mg-Ca alloys, and the unique properties of novel magnesium-calcium implant materials have been reviewed. Various manufacturing techniques to process Mg-Ca based alloys have been analyzed regarding their impacts on implant performance. Corrosion performance of Mg-Ca alloys processed by different manufacturing techniques was compared. In addition, the societal and economical impacts of developing biodegradable orthopedic implants have been emphasized.

Biodegradable Orthopedic Magnesium-Calcium (MgCa) Alloys, Processing, and Corrosion Performance

PubMed Central

Salahshoor, Meisam; Guo, Yuebin

2012-01-01

Magnesium-Calcium (Mg-Ca) alloy has received considerable attention as an emerging biodegradable implant material in orthopedic fixation applications. The biodegradable Mg-Ca alloys avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. They also provide sufficient mechanical strength in load carrying applications as opposed to biopolymers. However, the key issue facing a biodegradable Mg-Ca implant is the fast corrosion in the human body environment. The ability to adjust degradation rate of Mg-Ca alloys is critical for the successful development of biodegradable orthopedic implants. This paper focuses on the functions and requirements of bone implants and critical issues of current implant biomaterials. Microstructures and mechanical properties of Mg-Ca alloys, and the unique properties of novel magnesium-calcium implant materials have been reviewed. Various manufacturing techniques to process Mg-Ca based alloys have been analyzed regarding their impacts on implant performance. Corrosion performance of Mg-Ca alloys processed by different manufacturing techniques was compared. In addition, the societal and economical impacts of developing biodegradable orthopedic implants have been emphasized. PMID:28817036

Presidential Green Chemistry Challenge: 2001 Greener Synthetic Pathways Award

EPA Pesticide Factsheets

Presidential Green Chemistry Challenge 2001 award winners, Bayer Corporation and Bayer AG, developed a waste-free manufacturing process for sodium iminodisuccinate (Baypure CX), a biodegradable, nontoxic chelating agent.

Role of compostable tableware in food service and waste management. A life cycle assessment study.

PubMed

Fieschi, Maurizio; Pretato, Ugo

2018-03-01

It is estimated that in Europe 88-100 million tonnes of food waste are generated every year, with a Global Warming Potential (GWP) of around 227 MT of CO 2 equivalents generated for their collection and disposal. A 12% of this waste is estimated to arise from food service within the hospitality sector, which includes quick service restaurants, casual and fine dining, contract catering (canteens, prisons, hospitals, schools etc.) as well as indoor and outdoor events and exhibitions. Given this considerable amount and that the mixed unsorted collection is often the only practicable way to handle such waste flows, the choice of tableware and cutlery can make a big difference in facilitating waste collection as well as in reducing the overall environmental impact of food waste management. This study compares the environmental performance of using biodegradable & compostable single use tableware with organic recycling of food waste through composting against a traditional scenario using fossil-based plastic tableware and disposal of the waste flows through incineration and landfill. The study has taken into account the main requirements of the recently published Product Environmental Footprint (PEF) methodology of the European Commission. The results confirm that the use of biodegradable and compostable tableware combined with organic recycling is the preferred option for catering in quick service restaurants, contract catering and events, since it reduces significantly the carbon, water and resource footprint and is fully in line with the principles of a circular economy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biodegradability of degradable plastic waste.

PubMed

Agamuthu, P; Faizura, Putri Nadzrul

2005-04-01

Plastic waste constitutes the third largest waste volume in Malaysian municipal solid waste (MSW), next to putrescible waste and paper. The plastic component in MSW from Kuala Lumpur averages 24% (by weight), whereas the national mean is about 15%. The 144 waste dumps in the country receive about 95% of the MSW, including plastic waste. The useful life of the landfills is fast diminishing as the plastic waste stays un-degraded for more than 50 years. In this study the compostability of polyethylene and pro-oxidant additive-based environmentally degradable plastics (EDP) was investigated. Linear low-density polyethylene (LLDPE) samples exposed hydrolytically or oxidatively at 60 degrees C showed that the abiotic degradation path was oxidative rather than hydrolytic. There was a weight loss of 8% and the plastic has been oxidized as shown by the additional carbonyl group exhibited in the Fourier transform infra red (FTIR) Spectrum. Oxidation rate seemed to be influenced by the amount of pro-oxidant additive, the chemical structure and morphology of the plastic samples, and the surface area. Composting studies during a 45-day experiment showed that the percentage elongation (reduction) was 20% for McD samples [high-density polyethylene, (HDPE) with 3% additive] and LL samples (LLDPE with 7% additive) and 18% reduction for totally degradable plastic (TDP) samples (HDPE with 3% additive). Lastly, microbial experiments using Pseudomonas aeroginosa on carbon-free media with degradable plastic samples as the sole carbon source, showed confirmatory results. A positive bacterial growth and a weight loss of 2.2% for degraded polyethylene samples were evident to show that the degradable plastic is biodegradable.

What a Waste! A Teacher's Resource for Integrating the Solid Waste Crisis into the Classroom.

ERIC Educational Resources Information Center

Horosko, Millie M., Ed.

Although consumers are sensitive to purchasing products that are recyclable and biodegradable, which products are truly environmentally sound is not clear. This teacher guide contains activities to help educate students in grades 3-6 about choices they and their families make that may affect their future health and welfare. The lessons may be…

Movement and fate of creosote waste in ground water, Pensacola, Florida; U.S. Geological Survey toxic waste--ground-water contamination program

USGS Publications Warehouse

Mattraw, H. C.; Franks, B.J.

1984-01-01

In 1983, the U.S. Geological Survey, Office of Hazardous Waste Hydrology, selected the former American Creosote Works site near Pensacola, Florida as a national research demonstration area. Seventy-nine years (1902-81) of seepage from unlined discharge impoundments had released creosote, diesel fuel, and pentachlorophenol (since 1950) wastes into the ground-water system. A cluster of from 2 to 5 wells constructed at different depths at 9 sites yielded water which revealed contamination 600 feet downgradient and to a depth of 100 feet below land surface near the site. The best cross-sectional representation of the contaminant plume was obtained from samples collected and analyzed for oxidation-reduction sensitive inorganic chemical constituents. Energy dispersive x-ray fluorescence detected recently formed iron carbonate in soil samples from highly reducing ground-water zones. Approximately eighty specific organic contaminants were isolated from ground-water samples by gas-chromotography/mass spectrometry. Column studies indicate the dimethyl phenols are not sorbed or degraded by the sand-and-gravel aquifer materials. Five of nineteen individual phenolic and related compounds are biodegradable based on anaerobic digestor experiments with ACW site bacterial populations. The potential impacts in the nearby Pensacola Bay biotic community are being evaluated. (USGS)

Biodegradable soy protein isolate-based materials: a review.

PubMed

Song, Fei; Tang, Dao-Lu; Wang, Xiu-Li; Wang, Yu-Zhong

2011-10-10

Recently, there is an increasing interest of using bio-based polymers instead of conventional petroleum-based polymers to fabricate biodegradable materials. Soy protein isolate (SPI), a protein with reproducible resource, good biocompatibility, biodegradability, and processability, has a significant potential in the food industry, agriculture, bioscience, and biotechnology. Up to now, several technologies have been applied to prepare SPI-based materials with equivalent or superior physical and mechanical properties compared with petroleum-based materials. The aim of this review is focused on discussion of the advantages and limitations of native SPI as well as the bulk and surface modification strategies for SPI. Moreover, some applications of SPI-based materials, especially for food preservation and packaging technology, were discussed.

Disposable diapers biodegradation by the fungus Pleurotus ostreatus.

PubMed

Espinosa-Valdemar, Rosa María; Turpin-Marion, Sylvie; Delfín-Alcalá, Irma; Vázquez-Morillas, Alethia

2011-08-01

This research assesses the feasibility of degrading used disposable diapers, an important component (5-15% in weight) of urban solid waste in Mexico, by the activity of the fungus Pleurotus ostreatus, also known as oyster mushroom. Disposable diapers contain polyethylene, polypropylene and a super absorbent polymer. Nevertheless, its main component is cellulose, which degrades slowly. P. ostreatus has been utilized extensively to degrade cellulosic materials of agroindustrial sources, using in situ techniques. The practice has been extended to the commercial farming of the mushroom. This degradation capacity was assayed to reduce mass and volume of used disposable diapers. Pilot laboratory assays were performed to estimate the usefulness of the following variables on conditioning of used diapers before they act as substrate for P. ostreatus: (1) permanence vs removal of plastic cover; (2) shredding vs grinding; (3) addition of grape wastes to improve structure, nitrogen and trace elements content. Wheat straw was used as a positive control. After 68 days, decrease of the mass of diapers and productivity of fungus was measured. Weight and volume of degradable materials was reduced up to 90%. Cellulose content was diminished in 50% and lignine content in 47%. The highest efficiency for degradation of cellulosic materials corresponded to the substrates that showed highest biological efficiency, which varied from 0% to 34%. Harvested mushrooms had good appearance and protein content and were free of human disease pathogens. This research indicates that growing P. ostreatus on disposable diapers could be a good alternative for two current problems: reduction of urban solid waste and availability of high protein food sources. Copyright © 2011 Elsevier Ltd. All rights reserved.

Poland petroleum refinery sludge lagoon demonstration project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Altman, D.J.

The US Department of Energy and the Institute for Ecology of Industrial Area have been working together to develop mutually beneficial, cost-effective environmental remediation technologies such as the demonstration of bioremediation techniques for the clean up of acidic petroleum sludge impacted soils at an oil refinery in southern Poland. After an expedited site characterization, treatability study, and a risk assessment study, a remediation strategy was devised. The waste material was composed primarily of high molecular weight paraffinic and polynuclear aromatic hydrocarbons. A biopile design which employed a combination of passive and active aeration in conjunction with nutrient and surfactant applicationmore » as used to increase the biodegradation of the contaminants of concern.« less

Effect of Solids Retention Time on the Denitrification Potential of Anaerobically Digested Swine Waste

NASA Astrophysics Data System (ADS)

Kinyua, Maureen Njoki

Three continuously stirred tank reactors (CSTR) were operated in semi continuous mode treating swine waste using anaerobic digestion. The reactors were used to test the effect of solid retention time (SRT) on CH4 yield, total ammonia nitrogen (TAN) concentrations, % volatile solids (VS), chemical oxygen demand (COD) and volatile fatty acids (VFA) removal, readily biodegradable COD concentration and the denitrification potential for the effluent in a biological nutrient removal (BNR) system. During Phase I of the study, the three reactors were operated at the same 28 day SRT for 16 weeks. SRTs were then changed during the 12 week Phase II period. The SRTs studied were 14, 21 and 28 days, with the same organic loading rate (OLR) of 1.88 ± 0.2 kg VS/ m3-day. The reactor with the lowest SRT (14 days) had the highest VS and VFA removal at 73.6 and 67.6% and lowest TAN concentration at 0.78 g NH4+-N/L, followed by the 21 day and 28 day reactors. This was likely due to the fast microbial growth rates and substrate utilization rates in this reactor compared with the other two. The 14 day reactor had the highest CH4 yield at 0.33 m3CH 4/kg VS added and readily biodegradable COD concentration at 0.93 COD/L. The variations in CH4 yield and readily biodegradable COD concentrations between the three reactors were not statistically significant. Denitrification potential for the reactors was 1.20, 0.73 and 0.56 g COD/g N for 14, 21 and 28 day reactors, respectively, and the differences were statistically significant. None of the reactors achieved a denitrification potential of 5 g COD/g N, the amount required to use effluent of anaerobically digested swine waste as an internal carbon source in a BNR. This was attributed to operating conditions such as freezing and thawing of the raw swine waste that maximized CH4 yield and lowered the readily biodegradable COD concentration. In addition the 14 day reactor had low TAN concentrations thus increasing the denitrification potential of the centrate from that reactor.

Determining the bio-based content of bio-plastics used in Thailand by radiocarbon analysis

NASA Astrophysics Data System (ADS)

Ploykrathok, T.; Chanyotha, S.

2017-06-01

Presently, there is an increased interest in the development of bio-plastic products from agricultural materials which are biodegradable in order to reduce the problem of waste disposal. Since the amount of modern carbon in bio-plastics can indicate how much the amount of agricultural materials are contained in the bio-plastic products, this research aims to determine the modern carbon in bio-plastic using the carbon dioxide absorption method. The radioactivity of carbon-14 contained in the sample is measured by liquid scintillation counter (Tri-carb 3110 TR, PerkinElmer). The percentages of bio-based content in the samples were determined by comparing the observed modern carbon content with the values contained in agricultural raw materials. The experimental results show that only poly(lactic acid) samples have the modern carbon content of 97.4%, which is close to the agricultural materials while other bio-plastics types are found to have less than 50% of the modern carbon content. In other words, most of these bio-plastic samples were mixed with other materials which are not agriculturally originated.

Green synthesis and characterization of hybrid collagen-cellulose-albumin biofibers from skin waste.

PubMed

Amsaveni, Manickam; Anumary, Ayyappan; Ashokkumar, Meiyazhagan; Chandrasekaran, Bangaru; Thanikaivelan, Palanisamy

2013-11-01

Collagen (C) and cellulose are prominent biopolymers from the animal and plant kingdom and widely used in bioengineering. Albumin, on the other hand, is the most abundant plasma protein present in mammalian blood. In this work, collagen extracted from animal skin waste was blended with hydroxyethyl cellulose (HEC) and bovine serum albumin (A) and wet-spun to form hybrid biodegradable C/HEC/A fibers. They were further cross-linked with glutaraldehyde vapors and analyzed. X-ray diffraction and infra-red spectroscopic studies of the hybrid fibers display peaks corresponding to collagen, cellulose, and albumin. Incorporation of cellulose into the biopolymeric matrix leads to a reasonable improvement in mechanical, swelling, and thermal properties of hybrid fibers. Addition of albumin improves the regularity of fiber surface without altering the porosity as observed under a microscope. Hence, the formed hybrid biofibers can be potentially used as a suture material as well as for different biomedical applications due to their improved properties.

Influence of copper composition on mechanical properties of biodegradable material Mg-Zn-Cu for orthopedic application

NASA Astrophysics Data System (ADS)

Purniawan, A.; Maulidiah, H. M.; Purwaningsih, H.

2018-04-01

Implant is usually used as a treatment of bone fracture. At the moment, non-biodegradable implants is still widely employed in this application. Non-biodegradable implant requires re-surgery to retrieve implants that are installed in the body. It increase the cost and it is painful for the patient itself. In order to solve the problem, Mg-based biodegradable metals is developing so that the material will be compatible with body and gradually degrade in patient's body. However, magnesium has several disadvantages such as high degradation rates and low mechanical properties when compared to the mechanical properties of natural bone. Therefore, it is necessary to add elements into the magnesium alloy. In this research, copper (Cu) was alloyed in Mg alloy based biodegradable material. In addition, Cu is not only strengthening the structure but also for supporting element for the immune system, antibacterial and antifungal. The purpose of this research is to improve mechanical properties of Mg-based biodegradable material using Cu alloying. Powder metallurgy method was used to fabricate the device. The variation used in this research is the composition of Cu (0.5, 1, and 1.5% Cu). The porosity test was performed using apparent porosity test, compressive test and hardness test to know the mechanical properties of the alloy, and the weightless test to find out the material degradation rate. Based on the results can be conclude that Mg-Zn-Cu alloy material with 1% Cu composition is the most suitable specimen to be applied as a candidate for orthopedic devices material with hardness value is 393.6 MPa. Also obtained the value of the compressive test is 153 MPa.

Biodegradation of PVP-CMC hydrogel film: a useful food packaging material.

PubMed

Roy, Niladri; Saha, Nabanita; Kitano, Takeshi; Saha, Petr

2012-06-20

Hydrogels can offer new opportunities for the design of efficient packaging materials with desirable properties (i.e. durability, biodegradability and mechanical strength). It is a promising and emerging concept, as most of the biopolymer based hydrogels are supposed to be biodegradable, they can be considered as alternative eco-friendly packaging materials. This article reports about synthetic (polyvinylpyrrolidone (PVP)) and biopolymer (carboxymethyl cellulose (CMC)) based a novel hydrogel film and its nature of biodegradability under controlled environmental condition. The dry hydrogel films were prepared by solution casting method and designated as 'PVP-CMC hydrogel films'. The hydrogel film containing PVP and CMC in a ratio of 20:80 shows best mechanical properties among all the test samples (i.e. 10:90, 20:80, 50:50, 80:20 and 90:10). Thus, PVP-CMC hydrogel film of 20:80 was considered as a useful food packaging material and further experiments were carried out with this particular hydrogel film. Biodegradation of the PVP-CMC hydrogel films were studied in liquid state (Czapec-Dox liquid medium+soil extracts) until 8 weeks. Variation in mechanical, viscoelastic properties and weight loss of the hydrogel films with time provide the direct evidence of biodegradation of the hydrogels. About 38% weight loss was observed within 8 weeks. FTIR spectra of the hydrogel films (before and after biodegradation) show shifts of the peaks and also change in the peak intensities, which refer to the physico-chemical change in the hydrogel structure and SEM views of the hydrogels show how internal structure of the PVP-CMC film changes in the course of biodegradation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Methanogenic biodegradation of charcoal production wastes in groundwater at Kingsford, Michigan, USA

USGS Publications Warehouse

Michael, Godsy E.; Warren, E.; Westjohn, D.B.

2001-01-01

A house exploded in the City of Kingsford, Michigan USA. The explosion was caused by CH4 that leaked into the basement from the surrounding soil. Evidence suggests that biodegradation of products from the distillation and spillage at or near a former wood carbonization plant site was the major source of CH4 and CO2 in the groundwater system. The plant area is directly upgradient from deep groundwater, samples of which are green-yellow in colour, have a very strong odour of burnt wood, contain high concentrations of mononuclear aromatic and phenolic compounds, and extremely high concentrations of volatile fatty acids. The majority of the dissolved compounds in these groundwater samples have been shown, using laboratory microcosms, to be anaerobically biodegradable to CH4 and CO2. The biodegradable compounds, and the amounts of CH4 and CO2 produced in the microcosms, are consistent with observations from field samples.

Biological removal of phenol from wastewaters: a mini review

NASA Astrophysics Data System (ADS)

Pradeep, N. V.; Anupama, S.; Navya, K.; Shalini, H. N.; Idris, M.; Hampannavar, U. S.

2015-06-01

Phenol and its derivatives are common water pollutants and include wide variety of organic chemicals. Phenol poisoning can occur by skin absorption, inhalation, ingestion and various other methods which can result in health effects. High exposures to phenol may be fatal to human beings. Accumulation of phenol creates toxicity both for flora and fauna. Therefore, removal of phenol is crucial to perpetuate the environment and individual. Among various treatment methods available for removal of phenols, biodegradation is environmental friendly. Biological methods are gaining importance as they convert the wastes into harmless end products. The present work focuses on assessment of biological removal (biodegradation) of phenol. Various factors influence the efficiency of biodegradation of phenol such as ability of the microorganism, enzymes involved, the mechanism of degradation and influencing factors. This study describes about the sources of phenol, adverse effects on the environment, microorganisms involved in the biodegradation (aerobic and anaerobic) and enzymes that polymerize phenol.

A biodegradation study of forest biomass by Aspergillus niger F7: correlation between enzymatic activity, hydrolytic percentage and biodegradation index

PubMed Central

Sharma, Nivedita; Kaushal, Richa; Gupta, Rakesh; Kumar, Sanjeev

2012-01-01

Aspergillus niger F7 isolated from soil was found to be the potent producer of cellulase and xylanase. The residue of forest species Toona ciliata, Celtris australis, Cedrus deodara and Pinus roxburghii was selected as substrate for biodegradation study due to its easy availability and wide use in industry. It was subjected to alkali (sodium hydroxide) treatment for enhancing its degradation. Biodegradation of forest waste by hydrolytic enzymes (cellulase and xylanase) secreted by A. niger under solid state fermentation (SSF) was explored. SSF of pretreated forest biomass was found to be superior over untreated forest biomass. Highest extracellular enzyme activity of 2201±23.91 U/g by A. niger was shown in pretreated C. australis wood resulting in 6.72±0.20 percent hydrolysis and 6.99±0.23 biodegradation index (BI). The lowest BI of 1.40±0.08 was observed in untreated saw dust of C. deodara having the least enzyme activity of 238±1.36 U/g of dry matter. Biodegradation of forest biomass under SSF was increased many folds when moistening agent i.e. tap water had been replaced with modified basal salt media (BSM). In BSM mediated degradation of forest waste with A. niger, extracellular enzyme activity was increased up to 4089±67.11 U/g of dry matter in turn resulting in higher BI of 15.4±0.41 and percent hydrolysis of 19.38±0.81 in pretreated C. australis wood. A. niger exhibited higher enzyme activity on pretreated biomass when moistened with modified BSM in this study. Statistically a positive correlation has been drawn between these three factors i.e. enzyme activity, BI and percent hydrolysis of forest biomass thus proving their direct relationship with each other. PMID:24031853

Structure-biodegradability study and computer-automated prediction of aerobic biodegradation of chemicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klopman, G.; Tu, M.

1997-09-01

It is shown that a combination of two programs, MultiCASE and META, can help assess the biodegradability of industrial organic materials in the ecosystem. MultiCASE is an artificial intelligence computer program that had been trained to identify molecular substructures believed to cause or inhibit biodegradation and META is an expert system trained to predict the aerobic biodegradation products of organic molecules. These two programs can be used to help evaluate the fate of disposed chemicals by estimating their biodegradability and the nature of their biodegradation products under conditions that may model the environment.

Acquisition of the Concept "Biodegradable" Through Written Instruction: Pretest and Age Effects.

ERIC Educational Resources Information Center

Arganian, Mourad P.; And Others

The primary purpose of this study/experiment was to determine whether children in the middle elementary grades would be able to learn the concepts "biodegradable agent,""biodegradable material," and "biodegradable process" from a short written lesson. Secondary purposes were to examine the degree to which a pretest, grade level, and sex of the…

Effect of Material Parameters on Mechanical Properties of Biodegradable Polymers/Nanofibrillated Cellulose (NFC) Nano Composites

Treesearch

Yottha Srithep; Ronald Sabo; Craig Clemons; Lih-Sheng Turng; Srikanth Pilla; Jun Peng

2012-01-01

Using natural cellulosic fibers as fillers for biodegradable polymers can result in fully biodegradable composites. Biodegradable composites were prepared using nanofibrillated cellulose (NFC) as the reinforcement and poly (3-hydroxybutyrate-co-3-hydroxyvalerate, PHBV) as the polymer matrix. The objective of this study was to determine how various additives (i.e.,...

Models, Tools, and Databases for Land and Waste Management Research

EPA Pesticide Factsheets

These publicly available resources can be used for such tasks as simulating biodegradation or remediation of contaminants such as hydrocarbons, measuring sediment accumulation at superfund sites, or assessing toxicity and risk.

Understanding the anaerobic biodegradability of food waste: Relationship between the typological, biochemical and microbial characteristics.

PubMed

Fisgativa, Henry; Tremier, Anne; Le Roux, Sophie; Bureau, Chrystelle; Dabert, Patrick

2017-03-01

In this study, an extensive characterisation of food waste (FW) was performed with the aim of studying the relation between FW characteristics and FW treatability through an anaerobic digestion process. In addition to the typological composition (paper, meat, fruits, vegetables contents, etc) and the physicochemical characteristics, this study provides an original characterisation of microbial populations present in FW. These intrinsic populations can actively participate to aerobic and anaerobic degradation with the presence of Proteobacteria and Firmicutes species for the bacteria and of Ascomycota phylum for the fungi. However, the characterisation of FW bacterial and fungi community shows to be a challenge because of the biases generated by the non-microbial DNA coming from plant and by the presence of mushrooms in the food. In terms of relations, it was demonstrated that some FW characteristics as the density, the volatile solids and the fibres content vary as a function of the typological composition. No direct relationship was demonstrated between the typological composition and the anaerobic biodegradability. However, the Pearson's matrix results reveal that the anaerobic biodegradation potential of FW was highly related to the total chemical oxygen demand (tCOD), the total solid content (TS), the high weight organic matter molecules soluble in water (SOL W >1.5 kDa) and the C/N ratio content. These relations may help predicting FW behaviour through anaerobic digestion process. Finally, this study also showed that the storage of FW before collection, that could induce pre-biodegradation, seems to impact several biochemical characteristics and could improve the biodegradability of FW. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biosorption of 2,4,6-trichlorophenol from Aqueous Medium Using Agro-waste: Pine (Pinus densiflora Sieb) Bark Powder.

PubMed

Siva Kumar, Nadavala; Asif, Mohammad; Al-Hazzaa, Mansour I; Ibrahim, Ahmed A

2018-03-01

Most industrial waste discharges are often contaminated with phenolic compounds, which constitute a major source of water pollution owing to their toxicity and low biodegradability. Development of cost-effective treatment of such industrial wastewater is therefore of paramount importance. Towards this end, we explore the efficacy of Pine bark powder (PBP), which is an agricultural solid waste material, as a low-cost biosorbent without any pre-treatment, for the adsorptive removal of 2,4,6-trichlorophenol (2,4,6-TCP) from aqueous media. The PBP was thoroughly characterized and the effect of important adsorption parameters were examined in the present investigation. The batch equilibrium data were analyzed using well-known isotherm models. Freundlich isotherm model provided the best description of the equilibrium biosorption behavior. At 25 ± 1 °C, the maximum biosorption capacity (qmax) was 289.09 mg/g, which is higher than most biosorbents reported in the literature while the removal as high as 97% was obtained. Moreover, the biosorption process was fast, attaining equilibrium in less than 120 min of contact. The Elovich model accurately described the kinetics data. In view of high biosorption capacity and.

Using DDGS in industrial materials

USDA-ARS?s Scientific Manuscript database

Adding biological materials as fillers to plastics can enhance any existing biodegradability or provide biodegradability where none had previously existed. One potential biofiller is DDGS. In fact, several studies have been conducted recently that have investigated the use of DDGS in various plast...

Biodegradable Metals for Cardiovascular Stent Application: Interests and New Opportunities

PubMed Central

Moravej, Maryam; Mantovani, Diego

2011-01-01

During the last decade, biodegradable metallic stents have been developed and investigated as alternatives for the currently-used permanent cardiovascular stents. Degradable metallic materials could potentially replace corrosion-resistant metals currently used for stent application as it has been shown that the role of stenting is temporary and limited to a period of 6–12 months after implantation during which arterial remodeling and healing occur. Although corrosion is generally considered as a failure in metallurgy, the corrodibility of certain metals can be an advantage for their application as degradable implants. The candidate materials for such application should have mechanical properties ideally close to those of 316L stainless steel which is the gold standard material for stent application in order to provide mechanical support to diseased arteries. Non-toxicity of the metal itself and its degradation products is another requirement as the material is absorbed by blood and cells. Based on the mentioned requirements, iron-based and magnesium-based alloys have been the investigated candidates for biodegradable stents. This article reviews the recent developments in the design and evaluation of metallic materials for biodegradable stents. It also introduces the new metallurgical processes which could be applied for the production of metallic biodegradable stents and their effect on the properties of the produced metals. PMID:21845076

Forecasting municipal solid waste generation using prognostic tools and regression analysis.

PubMed

Ghinea, Cristina; Drăgoi, Elena Niculina; Comăniţă, Elena-Diana; Gavrilescu, Marius; Câmpean, Teofil; Curteanu, Silvia; Gavrilescu, Maria

2016-11-01

For an adequate planning of waste management systems the accurate forecast of waste generation is an essential step, since various factors can affect waste trends. The application of predictive and prognosis models are useful tools, as reliable support for decision making processes. In this paper some indicators such as: number of residents, population age, urban life expectancy, total municipal solid waste were used as input variables in prognostic models in order to predict the amount of solid waste fractions. We applied Waste Prognostic Tool, regression analysis and time series analysis to forecast municipal solid waste generation and composition by considering the Iasi Romania case study. Regression equations were determined for six solid waste fractions (paper, plastic, metal, glass, biodegradable and other waste). Accuracy Measures were calculated and the results showed that S-curve trend model is the most suitable for municipal solid waste (MSW) prediction. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of exogenous aerobic bacteria on methane production and biodegradation of municipal solid waste in bioreactors.

PubMed

Ge, Sai; Liu, Lei; Xue, Qiang; Yuan, Zhiming

2016-09-01

Landfill is the most common and efficient ways of municipal solid waste (MSW) disposal and the landfill biogas, mostly methane, is currently utilized to generate electricity and heat. The aim of this work is to study the effects and the role of exogenous aerobic bacteria mixture (EABM) on methane production and biodegradation of MSW in bioreactors. The results showed that the addition of EABM could effectively enhance hydrolysis and acidogenesis processes of MSW degradation, resulting in 63.95% reduction of volatile solid (VS), the highest methane production rate (89.83Lkg(-1) organic matter) ever recorded and a threefold increase in accumulative methane production (362.9L) than the control (127.1L). In addition, it is demonstrated that white-rot fungi (WRF) might further promote the methane production through highly decomposing lignin, but the lower pH value in leachate and longer acidogenesis duration may cause methane production reduced. The data demonstrated that methane production and biodegradation of MSW in bioreactors could be significantly enhanced by EABM via enhanced hydrolysis and acidogenesis processes, and the results are of great economic importance for the future design and management of landfill. Copyright © 2015 Elsevier Ltd. All rights reserved.

Combined thermo-chemo-sonic disintegration of waste activated sludge for biogas production.

PubMed

Kavitha, S; Yukesh Kannah, R; Yeom, Ick Tae; Do, Khac-Uan; Banu, J Rajesh

2015-12-01

In the present study, there was an investigation about the impact of a new combined thermo-chemo-sonic disintegration of waste activated sludge (WAS) on biodegradability. The outcome of sludge disintegration reveals that maximum Suspended Solids (SS) reduction and Chemical Oxygen Demand (COD) solubilization effectuated at a specific energy input of 5290.5kJ/kgTS, and was found to be 20%, 16.4%, 15% and 27%, 22%, and 20%, respectively for the three alkalis (NaOH, KOH, and Ca(OH)2). The conversion coefficient of the Volatile Suspended Solids (VSS) to product Soluble COD (SCOD), calculated by nonlinear regression modeling, was found to be 0.5530gSCOD/gVSS, 0.4587gSCOD/gVSS, and 0.4195gSCOD/gVSS for NaOH, KOH, and Ca(OH)2, respectively. In the biodegradability studies, the parameter evaluation provides an estimate of parameter uncertainty and correlation, and elucidates that there is no significant difference in biodegradability (0.413gCOD/gCOD, 0.367gCOD/gCOD, and 0.342gCOD/gCOD) for three alkalis (NaOH, KOH, and Ca(OH)2). Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of dopant-free conductive bioelastomers

PubMed Central

Xu, Cancan; Huang, Yihui; Yepez, Gerardo; Wei, Zi; Liu, Fuqiang; Bugarin, Alejandro; Tang, Liping; Hong, Yi

2016-01-01

Conductive biodegradable materials are of great interest for various biomedical applications, such as tissue repair and bioelectronics. They generally consist of multiple components, including biodegradable polymer/non-degradable conductive polymer/dopant, biodegradable conductive polymer/dopant or biodegradable polymer/non-degradable inorganic additives. The dopants or additives induce material instability that can be complex and possibly toxic. Material softness and elasticity are also highly expected for soft tissue repair and soft electronics. To address these concerns, we designed a unicomponent dopant-free conductive polyurethane elastomer (DCPU) by chemically linking biodegradable segments, conductive segments, and dopant molecules into one polymer chain. The DCPU films which had robust mechanical properties with high elasticity and conductivity can be degraded enzymatically and by hydrolysis. It exhibited great electrical stability in physiological environment with charge. Mouse 3T3 fibroblasts survived and proliferated on these films exhibiting good cytocompatibility. Polymer degradation products were non-toxic. DCPU could also be processed into a porous scaffold and in an in vivo subcutaneous implantation model, exhibited good tissue compatibility with extensive cell infiltration over 2 weeks. Such biodegradable DCPU with good flexibility and elasticity, processability, and electrical stability may find broad applications for tissue repair and soft/stretchable/wearable bioelectronics. PMID:27686216

[Biogas production from cellulose-containing substrates: a review].

PubMed

Tsavkelova, E A; Netrusov, A I

2012-01-01

Anaerobic microbial conversion of organic substrates to various biofuels is one of the alternative energy sources attracting the greatest attention of scientists. The advantages of biogas production over other technologies are the ability of methanogenic communities to degrade a broad range of substrates and concomitant benefits: neutralization of organic waste, reduction of greenhouse gas emission, and fertilizer production. Cellulose-containing materials are a good substrate, but their full-scale utilization encounters a number of problems, including improvement of the quality and amount ofbiogas produced and maintenance of the stability and high efficiency of microbial communities. We review data on microorganisms that form methanogenic cellulolytic communities, enzyme complexes of anaerobes essential for cellulose fiber degradation, and feedstock pretreatment, as biodegradation is hindered in the presence of lignin. Methods for improving biogas production by optimization of microbial growth conditions are considered on the examples of biogas formation from various types of plant and paper materials: writing paper and cardboard.

Fate and Tranport of MTBE in Clay-Rich Materials

NASA Astrophysics Data System (ADS)

lenczewski, m e

2001-12-01

A recent report by the U.S. Geological Survey identified methyl tert-butyl ether (MTBE), a constituent of reformulated gasoline, as the most common contaminant of urban aquifers in the United States. MTBE has been released into groundwater supplies by leaking underground fuel tanks. In Illinois, it has been found in 26 of the 1,800 public water supplies and although detection was intermittent, levels were high enough to be offensive to users in some Illinois communities. MTBE is also being used in Mexico to solve the problem of air quality; however, it has the potential to harm the drinking water quality in the process. Early research on MTBE considered it resistant to biodegradation and unable to adsorb to soils and sediments. However, recent evidence indicates that biodegradation does occur under certain conditions and that sorption can occur to organic materials. This research project will investigate the biodegradation of MTBE and its sorption to the clay-rich glacial till found in northern Illinois and lacustrine clays found in the Chalco Basin, Mexico City, Mexico whose interaction with MTBE has not previously been studied. The principal hypothesis of this research is that the microorganisms and environmental factors in clay-rich materials will increase the biodegradation and sorption of MTBE as compared to sandy materials. The experiments will simulate a spill of MTBE or downgradient from a gasoline spill. Microcosms and batch isotherm experiments will be used to demonstrate the potential for biodegradation and sorption in these materials; however, laboratory results are not considered reliable estimates of actual field sorption and biodegradation rates. Therefore long-term column experiments will also be conducted in which large sample volumes of material that simulate the heterogeneities naturally observed in the environment. This research will increase understanding of the biodegradation and sorption of MTBE and lay the necessary groundwork to implement the optimal remediation method for sites contaminated by MTBE, helping to ensure a sustainable groundwater resource.

A modern solid waste management strategy--the generation of new by-products.

PubMed

Fudala-Ksiazek, Sylwia; Pierpaoli, Mattia; Kulbat, Eliza; Luczkiewicz, Aneta

2016-03-01

To benefit the environment and society, EU legislation has introduced a 'zero waste' strategy, in which waste material should be converted to resources. Such legislation is supported by the solid waste hierarchy concept, which is a set of priorities in waste management. Under this concept, municipal solid waste plants (MSWPs) should be equipped with sorting and recycling facilities, composting/incineration units and landfill prisms for residual bulk disposal. However, each of the aforementioned facilities generates by-products that must be treated. This project focuses on the leachates from landfill prisms, including modern prism (MP) that meet EU requirements and previous prism (PP) that provide for the storage of permitted biodegradable waste as well as technological wastewaters from sorting unit (SU) and composting unit (CU), which are usually overlooked. The physico-chemical parameters of the liquid by-products collected over 38 months were supported by quantitative real-time PCR (qPCR) amplifications of functional genes transcripts and a metagenomic approach that describes the archaeal and bacterial community in the MP. The obtained data show that SU and especially CU generate wastewater that is rich in nutrients, organic matter and heavy metals. Through their on-site pre-treatment and recirculation via landfill prisms, the landfill waste decomposition process may be accelerated because of the introduction of organic matter and greenhouse gas emissions may be increased. These results have been confirmed by the progressive abundance of both archaeal community and the methyl coenzyme M reductase (mcrA) gene. The resulting multivariate data set, supported by a principal component analysis, provides useful information for the design, operation and risk assessment of modern MSWPs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Relationship between anaerobic digestion of biodegradable solid waste and spectral characteristics of the derived liquid digestate.

PubMed

Zheng, Wei; Lü, Fan; Phoungthong, Khamphe; He, Pinjing

2014-06-01

The evolution of spectral properties during anaerobic digestion (AD) of 29 types of biodegradable solid waste was investigated to determine if spectral characteristics could be used for assessment of biological stabilization during AD. Biochemical methane potential tests were conducted and spectral indicators (including the ratio of ultraviolet-visible absorbance at 254nm to dissolved organic carbon concentration (SUVA254), the ratio of ultraviolet-visible absorbance measured at 465nm and 665nm (E4/E6), and the abundance of fluorescence peaks) were measured at different AD phases. Inter-relationship between organic degradation and spectral indicators were analyzed by principle component analysis. The results shows that from methane production phase to the end of methane production phase, SUVA254 increased by 0.16-10.93 times, the abundance of fulvic acid-like compounds fluorescence peak increased by 0.01-0.54 times, the abundance of tyrosine fluorescence peak decreased by 0.03-0.64 times. Therefore, these indicators were useful to judge the course of mixed waste digestion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of ultrasonic and ozone pre-treatments on pharmaceutical waste activated sludge's solubilisation, reduction, anaerobic biodegradability and acute biological toxicity.

PubMed

Pei, Jin; Yao, Hong; Wang, Hui; Shan, Dan; Jiang, Yichen; Ma, Lanqianya; Yu, Xiaohua

2015-09-01

Ultrasonic and ozone pre-treatment technologies were employed in this study to improve the anaerobic digestion efficiency of pharmaceutical waste activated sludge. The sludge solubilisation achieved 30.01% (150,000 kJ/kg TS) and 28.10% (0.1g O3/g TS) after ultrasonic treatment and ozone treatment. The anaerobic biodegradability after ultrasonic treatment was higher compared to ozonation due to the higher cumulative methane volume observed after 6 days (249 ml vs 190 ml). The ozonated sludge released the highest concentration of Cu(2+) into the liquid phase (6.640 mg L(-1)) compared to 0.530 mg/L for untreated sludge and 0.991 mg/L for sonicated sludge. The acute toxicity test measured by luminescent bacteria showed that anaerobic digestion could degrade toxic compounds and result in a reduction in toxicity. The main mechanism of action led to some differences in the treated sludge exhibiting higher potential for methane production from pharmaceutical waste sludge with ultrasonic treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of clinical outcomes of three different packing materials in the treatment of severe acute otitis externa.

PubMed

Demir, D; Yılmaz, M S; Güven, M; Kara, A; Elden, H; Erkorkmaz, Ü

2018-06-13

To analyse the clinical outcomes of biodegradable synthetic polyurethane foam versus ribbon gauze and ear wick in the treatment of severe acute otitis externa. Ninety-two adults with severe acute otitis externa were randomly assigned to groups receiving ear wick (n = 28), ribbon gauze (n = 34) or biodegradable synthetic polyurethane foam (n = 30). Clinical efficacy, in terms of otalgia, oedema, erythema and tenderness of the external auditory canal, was assessed before packing was applied and at follow up on the 3rd and 7th days of presentation. All packing materials were associated with improved otalgia and oedema on the 3rd day; however, there were significant differences between biodegradable synthetic polyurethane foam and the other packing materials, and there was no significant reduction in tenderness in the biodegradable synthetic polyurethane foam group on the 3rd day. In the ribbon gauze and ear wick groups, improvements in all clinical efficacy scores were statistically significant for all pairwise comparisons. The three packing materials were all quite effective in treating severe acute otitis externa, but ear wick and ribbon gauze were superior to biodegradable synthetic polyurethane foam for relieving signs and symptoms, especially on the 3rd day.

Process Waste Assessment Machine and Fabrication Shop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phillips, N.M.

1993-03-01

This Process Waste Assessment was conducted to evaluate hazardous wastes generated in the Machine and Fabrication Shop at Sandia National Laboratories, Bonding 913, Room 119. Spent machine coolant is the major hazardous chemical waste generated in this facility. The volume of spent coolant generated is approximately 150 gallons/month. It is sent off-site to a recycler, but a reclaiming system for on-site use is being investigated. The Shop`s line management considers hazardous waste minimization very important. A number of steps have already been taken to minimize wastes, including replacement of a hazardous solvent with biodegradable, non-caustic solution and filtration unit; wastemore » segregation; restriction of beryllium-copper alloy machining; and reduction of lead usage.« less

Biological treatment of whey by Tetrahymena pyriformis and impact study on laboratory-scale wastewater lagoon process.

PubMed

Bonnet, J L; Bogaerts, P; Bohatier, J

1999-06-01

A procedure based on a biological treatment of whey was tested as part of research on waste treatment at the scale of small cheesemaking units. We studied the potential biodegradation of whey by a protozoan ciliate, Tetrahymena pyriformis, and evaluated the functional, microbiological and physiological disturbances caused by crude whey and the biodegraded whey in laboratory-scale pilots mimicking a natural lagoon treatment. The results show that T. pyriformis can strongly reduce the pollutant load of whey. In the lagoon pilots serving as example of receptor media, crude whey gradually but completely arrested operation, whereas with the biodegraded whey adverse effects were only temporary, and normal operation versus a control was gradually recovered in a few days.

Evaluation of biodegradable plastics for rubber seedling applications

NASA Astrophysics Data System (ADS)

Mansor, Mohd Khairulniza; Dayang Habibah A. I., H.; Kamal, Mazlina Mustafa

2015-08-01

The main negative consequence of conventional plastics in agriculture is related to handling the wastes plasticand the associated environmental impact. Hence, a study of different types of potentially biodegradable plastics used for nursery applications have been evaluated on its mechanical,water absorption propertiesand Fourier transform infra-red (FTIR) spectroscopy. Supplied samples from different companies were designated as SF, CF and CO. Most of the polybags exhibited mechanical properties quite similar to the conventional plastics (polybag LDPE). CO polybag which is based on PVA however had extensively higher tensile strength and water absorption properties. FTIR study revealed a characteristics absorbance of conventional plastic, SF, CF and CO biodegradable polybag are associated with polyethylene, poly(butylene adipate-co-terephthalate) (PBAT), polyethylene and polyvinyl alcohol (PVA) structures respectively.

Investigating the Microbial Degradation Potential in Oil Sands Fluid Fine Tailings Using Gamma Irradiation: A Metagenomic Perspective.

PubMed

VanMensel, Danielle; Chaganti, Subba Rao; Boudens, Ryan; Reid, Thomas; Ciborowski, Jan; Weisener, Christopher

2017-08-01

Open-pit mining of the Athabasca oil sands has generated large volumes of waste termed fluid fine tailings (FFT), stored in tailings ponds. Accumulation of toxic organic substances in the tailings ponds is one of the biggest concerns. Gamma irradiation (GI) treatment could accelerate the biodegradation of toxic organic substances. Hence, this research investigates the response of the microbial consortia in GI-treated FFT materials with an emphasis on changes in diversity and organism-related stimuli. FFT materials from aged and fresh ponds were used in the study under aerobic and anaerobic conditions. Variations in the microbial diversity in GI-treated FFT materials were monitored for 52 weeks and significant stimuli (p < 0.05) were observed. Chemoorganotrophic organisms dominated in fresh and aged ponds and showed increased relative abundance resulting from GI treatment. GI-treated anaerobic FFT aged reported stimulus of organisms with biodegradation potential (e.g., Pseudomonas, Enterobacter) and methylotrophic capabilities (e.g., Syntrophus, Smithella). In comparison, GI-treated anaerobic FFT fresh stimulated Desulfuromonas as the principle genus at 52 weeks. Under aerobic conditions, GI-treated FFT aged showed stimulation of organisms capable of sulfur and iron cycling (e.g., Geobacter). However, GI-treated aerobic FFT fresh showed no stimulus at 52 weeks. This research provides an enhanced understanding of oil sands tailings biogeochemistry and the impacts of GI treatment on microorganisms as an effect for targeting toxic organics. The outcomes of this study highlight the potential for this approach to accelerate stabilization and reclamation end points. Graphical Abstract.

Biodegradation potential of cyano-based ionic liquid anions in a culture of Cupriavidus spp. and their in vitro enzymatic hydrolysis by nitrile hydratase.

PubMed

Neumann, Jennifer; Pawlik, Magdalena; Bryniok, Dieter; Thöming, Jorg; Stolte, Stefan

2014-01-01

Biodegradation tests with bacteria from activated sludge revealed the probable persistence of cyano-based ionic liquid anions when these leave waste water treatment plants. A possible biological treatment using bacteria capable of biodegrading similar compounds, namely cyanide and cyano-complexes, was therefore examined. With these bacteria from the genera Cupriavidus, the ionic liquid anions B(CN)₄(-), C(CN)₃(-), N(CN)₂(-) combined with alkaline cations were tested in different growth media using ion chromatography for the examination of their primary biodegradability. However, no enhanced biodegradability of the tested cyano-based ionic liquids was observed. Therefore, an in vitro enzymatic hydrolysis test was additionally run showing that all tested ionic liquid (IL) anions can be hydrolysed to their corresponding amides by nitrile hydratase, but not by nitrilase under the experimental conditions. The biological stability of the cyano-based anions is an advantage in technological application, but the occurrence of enzymes that are able to hydrolyse the parent compound gives a new perspective on future cyano-based IL anion treatment.

Draft Genome Sequence of a Tetrabromobisphenol A–Degrading Strain, Ochrobactrum sp. T, Isolated from an Electronic Waste Recycling Site

PubMed Central

Liang, Zhishu; Li, Guiying; Zhang, Guoxia; Das, Ranjit

2016-01-01

Ochrobactrum sp. T was previously isolated from a sludge sample collected from an electronic waste recycling site and characterized as a unique tetrabromobisphenol A (TBBPA)–degrading bacterium. Here, the draft genome sequence (3.9 Mb) of Ochrobactrum sp. T is reported to provide insights into its diversity and its TBBPA biodegradation mechanism in polluted environments. PMID:27445374

Evaluation of laboratory-scale in-vessel co-composting of tobacco and apple waste.

PubMed

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.

Biodegradability and mechanical properties of poly-([beta]-hyroxybutyrate-Co-[beta]-hydroxyvalerate)-starch blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramsay, B.A.; Langlade, V.; Carreau, P.J.

1993-04-01

PHAs, biodegradable thermoplastics, are a promising option to synthetic resins such as polyethylene, in combination with starch, to produce biodegradable plastics. This paper describes the mechanical properties and biodegradability of blends of wheat starch and P(HB-co-HV). The results indicate that the addition of starch to P(HB-co-HV) not only reduces the cost but also leads to a completely biodegradable material whose degradation can be tailored by adjusting the starch/PHA ratio. 15 refs., 3 figs., 1 tab.

Impedance based sensor technology to monitor stiffness of biological structures

NASA Astrophysics Data System (ADS)

Annamdas, Venu Gopal Madhav; Annamdas, Kiran Kishore Kumar

2010-04-01

In countries like USA or Japan it is not so uncommon to have wooden structures in their homes. However, metals and its alloys are the most widely used engineering materials in construction of any military or civil structure. Revisiting natural disasters like the recent Haiti earthquake (12 Jan 2010) or Katrina (cyclones) reminds the necessity to have better housing infrastructure with robust monitoring systems. Traditionally wood is accepted as excellent rehabilitation material, after any disaster. The recycling materials extracted from in-organic, biodegradable wastes, also can be used for rehabilitation. The key issue which dampens the life of these rehabilitated structure including green materials (like wood) is unnecessary deposits (nails, screws, bolts etc)/damages due to insect attack. Thus, a few health monitoring techniques have emerged in the recent past. Electromechanical Impedance technique is one such technique, which is simple but robust to detect variations in the integrity of structures. In this paper, impedance based piezoceramic sensor was bonded on wooden sample, which was used to study changes due to metallic (steel nails) deposits at various locations. A study of weight deposits on aluminum plate was used for comparisons.

Metaproteomics reveals major microbial players and their biodegradation functions in a large-scale aerobic composting plant

PubMed Central

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

Co-biodrying of sewage sludge and organic fraction of municipal solid waste: Role of mixing proportions.

PubMed

Zhang, Difang; Luo, Wenhai; Yuan, Jing; Li, Guoxue

2018-04-26

This study investigated the performance of co-biodrying sewage sludge and organic fraction of municipal solid waste (OFMSW) at different proportions. Cornstalk was added at 15% (of total wet weight) as the bulking agent. Results show that increasing OFMSW percentage promoted the biodegradation of organic matter, thus enhancing the temperature integration value and water removal to above 75% during sludge and OFMSW co-biodrying. In particular, adding more OFMSW accelerated the biodegradation of soluble carbohydrates, lignins, lipids, and amylums, resulting in more organic loss and thus lower biodrying index (3.3-3.7 for 55-85% OFMSW). Water balance calculation indicated that evaporation was the main mechanism for water removal. Heat used for water evaporation was 37.7-48.6% of total heat consumption during co-biodrying. Our results suggest that sludge and OFMSW should be mixed equally for their efficient co-biodrying. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bioelectrohydrogenesis and inhibition of methanogenic activity in microbial electrolysis cells - A review.

PubMed

Karthikeyan, Rengasamy; Cheng, Ka Yu; Selvam, Ammaiyappan; Bose, Arpita; Wong, Jonathan W C

2017-11-01

Microbial electrolysis cells (MECs) are a promising technology for biological hydrogen production. Compared to abiotic water electrolysis, a much lower electrical voltage (~0.2V) is required for hydrogen production in MECs. It is also an attractive waste treatment technology as a variety of biodegradable substances can be used as the process feedstock. Underpinning this technology is a recently discovered bioelectrochemical pathway known as "bioelectrohydrogenesis". However, little is known about the mechanism of this pathway, and numerous hurdles are yet to be addressed to maximize hydrogen yield and purity. Here, we review various aspects including reactor configurations, microorganisms, substrates, electrode materials, and inhibitors of methanogenesis in order to improve hydrogen generation in MECs. Copyright © 2017 Elsevier Inc. All rights reserved.

Lunar base CELSS: A bioregenerative approach

NASA Technical Reports Server (NTRS)

Easterwood, G. W.; Street, J. J.; Sartain, J. B.; Hubbell, D. H.; Robitaille, H. A.

1992-01-01

During the twenty-first century, human habitation of a self-sustaining lunar base could become a reality. To achieve this goal, the occupants will have to have food, water, and an adequate atmosphere within a carefully designed environment. Advanced technology will be employed to support terrestrial life-sustaining processes on the Moon. One approach to a life support system based on food production, waste management and utilization, and product synthesis is outlined. Inputs include an atmosphere, water, plants, biodegradable substrates, and manufacutured materials such as fiberglass containment vessels from lunar resources. Outputs include purification of air and water, food, and hydrogen (H2) generated from methane (CH4). Important criteria are as follows: (1) minimize resupply from Earth; and (2) recycle as efficiently as possible.

The Molecular Level Characterization of Biodegradable Polymers Originated from Polyethylene Using Non-Oxygenated Polyethylene Wax as a Carbon Source for Polyhydroxyalkanoate Production.

PubMed

Johnston, Brian; Jiang, Guozhan; Hill, David; Adamus, Grazyna; Kwiecień, Iwona; Zięba, Magdalena; Sikorska, Wanda; Green, Matthew; Kowalczuk, Marek; Radecka, Iza

2017-08-28

There is an increasing demand for bio-based polymers that are developed from recycled materials. The production of biodegradable polymers can include bio-technological (utilizing microorganisms or enzymes) or chemical synthesis procedures. This report demonstrates the corroboration of the molecular structure of polyhydroxyalkanoates (PHAs) obtained by the conversion of waste polyethylene (PE) via non-oxygenated PE wax (N-PEW) as an additional carbon source for a bacterial species. The N-PEW, obtained from a PE pyrolysis reaction, has been found to be a beneficial carbon source for PHA production with Cupriavidus necator H16. The production of the N-PEW is an alternative to oxidized polyethylene wax (O-PEW) (that has been used as a carbon source previously) as it is less time consuming to manufacture and offers fewer industrial applications. A range of molecular structural analytical techniques were performed on the PHAs obtained; which included nuclear magnetic resonance (NMR) and electrospray ionisation tandem mass spectrometry (ESI-MS/MS). Our study showed that the PHA formed from N-PEW contained 3-hydroxybutyrate (HB) with 11 mol% of 3-hydroxyvalerate (HV) units.

The Molecular Level Characterization of Biodegradable Polymers Originated from Polyethylene Using Non-Oxygenated Polyethylene Wax as a Carbon Source for Polyhydroxyalkanoate Production

PubMed Central

Johnston, Brian; Jiang, Guozhan; Hill, David; Adamus, Grazyna; Zięba, Magdalena; Sikorska, Wanda; Green, Matthew; Kowalczuk, Marek

2017-01-01

There is an increasing demand for bio-based polymers that are developed from recycled materials. The production of biodegradable polymers can include bio-technological (utilizing microorganisms or enzymes) or chemical synthesis procedures. This report demonstrates the corroboration of the molecular structure of polyhydroxyalkanoates (PHAs) obtained by the conversion of waste polyethylene (PE) via non-oxygenated PE wax (N-PEW) as an additional carbon source for a bacterial species. The N-PEW, obtained from a PE pyrolysis reaction, has been found to be a beneficial carbon source for PHA production with Cupriavidus necator H16. The production of the N-PEW is an alternative to oxidized polyethylene wax (O-PEW) (that has been used as a carbon source previously) as it is less time consuming to manufacture and offers fewer industrial applications. A range of molecular structural analytical techniques were performed on the PHAs obtained; which included nuclear magnetic resonance (NMR) and electrospray ionisation tandem mass spectrometry (ESI-MS/MS). Our study showed that the PHA formed from N-PEW contained 3-hydroxybutyrate (HB) with 11 mol% of 3-hydroxyvalerate (HV) units. PMID:28952552

Biodegradable Sonobuoy Decelerators

DTIC Science & Technology

2015-06-01

material. Two materials studied were polyvinyl alcohol (PVOH) and polyhydroxyalkanoate (PHA). Single and multilayered PVOH films were evaluated as well...readiness point for technology transition. 15. SUBJECT TERMS biodegrade, decelerator, sonobuoy, polyvinyl alcohol, polyhydroxyalkanoate , marine...Center NGO non-governmental organizations NOAA National Oceanic and Atmospheric Administration PHA polyhydroxyalkanoate PIA Parachute Industry

Development of biodegradable foamlike materials based on casein and sodium montmorillonite clay

USDA-ARS?s Scientific Manuscript database

Biodegradable foamlike materials based on a naturally occurring polymer (casein protein) and sodium montmorillonite clay (Na+-MMT) were produced through a simple freeze-drying process. By utilizing DL-glyceraldehyde (GC) as a chemical cross-linking agent, the structural integrity of these new aeroge...

Healthy environments for healthy people: bioremediation today and tomorrow.

PubMed Central

Bonaventura, C; Johnson, F M

1997-01-01

Increases in environmental contamination lead to a progressive deterioration of environmental quality. This condition challenges our global society to find effective measures of remediation to reverse the negative conditions that severely threaten human and environmental health. We discuss the progress being made toward this goal through application of bioremediation techniques. Bioremediation generally utilizes microbes (bacteria, fungi, yeast, and algae), although higher plants are used in some applications. New bioremediation approaches are emerging based on advances in molecular biology and process engineering. Bioremediation continues to be the favored approach for processing biological wastes and avoiding microbial pathogenesis. Bioremediation may also play an increasing role in concentrating metals and radioactive materials to avoid toxicity or to recover metals for reuse. Microbes can biodegrade organic chemicals; purposeful enhancement of this natural process can aid in pollutant degradation and waste-site cleanup operations. Recently developed rapid-screening assays can identify organisms capable of degrading specific wastes and new gene-probe methods can ascertain their abundance at specific sites. New tools and techniques for use of bioremediation in situ, in biofilters, and in bioreactors are contributing to the rapid growth of this field. Bioremediation has already proven itself to be a cost-effective and beneficial addition to chemical and physical methods of managing wastes and environmental pollutants. We anticipate that it will play an increasingly important role as a result of new and emerging techniques and processes. Images Figure 3. PMID:9114274

Impact of paper and cardboard suppression on OFMSW anaerobic digestion.

PubMed

Fonoll, X; Astals, S; Dosta, J; Mata-Alvarez, J

2016-10-01

Mechanical-biological treatment plants treat municipal solid waste to recover recyclable materials, nutrients and energy. Waste paper and cardboard (WP), the second main compound in municipal solid waste (∼30% in weight basis), is typically used for biogas generation. However, its recovery is gaining attention as it can be used to produce add-value products like bioethanol and residual derived fuel. Nevertheless, WP suppression or replacement will impact anaerobic digestion in terms of biogas production, process stability and digestate management. Two lab-scale reactors were used to assess the impact of WP in anaerobic digestion performance. A control reactor was only fed with biowaste (BioW), while a second reactor was fed with two different mixtures of BioW and WP, i.e. 85/15% and 70/30% (weight basis). Results indicate that either replacing half of the WP by BioW or removing half of the WP has little impact on the methane production. When removing half of the WP, methane production could be sustained by a larger waste biodegradability. The replacement of all WP by BioW increased the reactor methane production (∼37%), while removing all WP would have reduced the methane production about 15%. Finally, replacing WP loading rate by BioW led to a system less tolerant to instability periods and with poorer digestate quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

Short-Term and Long-Term Effects of Orthopedic Biodegradable Implants

PubMed Central

Amini, Ami R.; Wallace, James S.; Nukavarapu, Syam P.

2012-01-01

Presently, orthopedic and oral/maxillofacial implants represent a combined $2.8 billion market, a figure expected to experience significant and continued growth. Although traditional permanent implants have been proved clinically efficacious, they are also associated with several drawbacks, including secondary revision and removal surgeries. Non-permanent, biodegradable implants offer a promising alternative for patients, as they provide temporary support and degrade at a rate matching tissue formation, and thus, eliminate the need for secondary surgeries. These implants have been in clinical use for nearly 25 years, competing directly with, or maybe even exceeding, the performance of permanent implants. The initial implantation of biodegradable materials, as with permanent materials, mounts an acute host inflammatory response. Over time, the implant degradation profile and possible degradation product toxicity mediate long-term biodegradable implant-induced inflammation. However, unlike permanent implants, this inflammation is likely to cease once the material disappears. Implant-mediated inflammation is a critical determinant for implant success. Thus, for the development of a proactive biodegradable implant that has the ability to promote optimal bone regeneration and minimal detrimental inflammation, a thorough understanding of short- and long-term inflammatory events is required. Here, we discuss an array of biodegradable orthopedic implants, their associated short- and long- term inflammatory effects, and methods to mediate these inflammatory events. PMID:22043969

Evolution of biodegradation of deinking by-products used as alternative cover material.

PubMed

Aït-Benichou, Samah; Rodrigues Cabral, Alexandre; Teixeira Panarotto, Claudia

2008-01-01

Deinking by-products (DBP) have been used as alternative cover material for landfills and mine tailings. Since DBP is biodegradable because of its high cellulose and hemicellulose content, a laboratory experimental program was performed to monitor the evolution of biodegradation and changes in the physico-chemical and geotechnical properties of DBP samples submitted to accelerated biodegradation for 1460 days at 38 degrees C. The evolution of gas and leachate production was monitored in terms of both quality and quantity, which allowed for the calculation of mass loss with time. Under the conditions of the tests (no load applied), 19.6% of the mass was lost as gas, whereas 6.1% was leached out. The results show that biodegradation did not significantly alter the compaction behavior of DBP. The void ratio and water content increased significantly, while the volume of the samples slightly decreased. This seem to indicate that the porous structure of the samples was no longer the same after 1460 d of accelerated biodegradation. A slight increase in the relative density indicates that the organic/inorganic matter ratio increased. The results of permeability tests performed with samples at various stages of biodegradation and at various confining stresses show that the saturated hydraulic conductivity of recompacted biodegraded DBP decreased from 7 x 10(-7)cm/s to approximately 2 x 10(-7)cm/s, as biodegradation advanced.

Characterization of exposure in epidemiological studies on air pollution from biodegradable wastes: Misclassification and comparison of exposure assessment strategies.

PubMed

Cantuaria, Manuella Lech; Suh, Helen; Løfstrøm, Per; Blanes-Vidal, Victoria

2016-11-01

The assignment of exposure is one of the main challenges faced by environmental epidemiologists. However, misclassification of exposures has not been explored in population epidemiological studies on air pollution from biodegradable wastes. The objective of this study was to investigate the use of different approaches for assessing exposure to air pollution from biodegradable wastes by analyzing (1) the misclassification of exposure that is committed by using these surrogates, (2) the existence of differential misclassification (3) the effects that misclassification may have on health effect estimates and the interpretation of epidemiological results, and (4) the ability of the exposure measures to predict health outcomes using 10-fold cross validation. Four different exposure assessment approaches were studied: ammonia concentrations at the residence (Metric I), distance to the closest source (Metric II), number of sources within certain distances from the residence (Metric IIIa,b) and location in a specific region (Metric IV). Exposure-response models based on Metric I provided the highest predictive ability (72.3%) and goodness-of-fit, followed by IV, III and II. When compared to Metric I, Metric IV yielded the best results for exposure misclassification analysis and interpretation of health effect estimates, followed by Metric IIIb, IIIa and II. The study showed that modelled NH 3 concentrations provide more accurate estimations of true exposure than distances-based surrogates, and that distance-based surrogates (especially those based on distance to the closest point source) are imprecise methods to identify exposed populations, although they may be useful for initial studies. Copyright © 2016 Elsevier GmbH. All rights reserved.

Starch-based edible film with gum arabic for fruits coating

NASA Astrophysics Data System (ADS)

Razak, Aqeela Salfarina; Lazim, Azwan Mat

2015-09-01

Packaging waste forms a significant part of municipal solid waste and has caused increasing environmental concerns, resulting in a strengthening of various regulations aimed at reducing the amounts generated. The introduction of biodegradable materials such as edible film and coating which can be disposed directly into the soil, can be one possible solution to this problem. Edible coating is defined as a thin layer of edible material form as a film on the surface of the fruits and vegetables. This coating can affect the respiration and moisture loss. In this study, edible film and coating were used as fruit coating. The edible film were prepared with different ratios which is 2:2, 3:1, and 1:3 of starch and gum Arabic with 10% of glycerol and sorbitol as plasticiser. A study of practical application for the edible film and coating from starch with gum Arabic for fruit coating was conducted. Banana were coated with an aqueous solution of starch with gum Arabic and stored at ambient temperature (26 ± 1°C; 70 ± 10% RH). The results indicate that with the coating application, the fruits lost about 30% less weight than the uncoated fruits. The coating application was also effective in retaining the firmness of the banana and slow down the ripening process.

High solids co-digestion of food and landscape waste and the potential for ammonia toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drennan, Margaret F.; DiStefano, Thomas D., E-mail: thomas.distefano@bucknell.edu

Highlights: • We evaluated co-digestion of food and landscape waste with a pilot-scale anaerobic dry digester. • We evaluated reactor performance at 35 °C under low and high organic loading rates. • Performance was stable under low organic loading rate, but declined under high organic loading rate. • Respirometry was employed to investigate potential inhibition due to ammonia. • Landscape waste was unsuitable in increasing the C:N ratio during codigestion. - Abstract: A pilot-scale study was completed to determine the feasibility of high-solids anaerobic digestion (HSAD) of a mixture of food and landscape wastes at a university in central Pennsylvaniamore » (USA). HSAD was stable at low loadings (2 g COD/L-day), but developed inhibitory ammonia concentrations at high loadings (15 g COD/L-day). At low loadings, methane yields were 232 L CH{sub 4}/kg COD fed and 229 L CH{sub 4}/kg VS fed, and at high loadings yields were 211 L CH{sub 4}/kg COD fed and 272 L CH{sub 4}/kg VS fed. Based on characterization and biodegradability studies, food waste appears to be a good candidate for HSAD at low organic loading rates; however, the development of ammonia inhibition at high loading rates suggests that the C:N ratio is too low for use as a single substrate. The relatively low biodegradability of landscape waste as reported herein made it an unsuitable substrate to increase the C:N ratio. Codigestion of food waste with a substrate high in bioavailable carbon is recommended to increase the C:N ratio sufficiently to allow HSAD at loading rates of 15 g COD/L-day.« less

Energy recovery from solid waste. Volume 1: Summary report

NASA Technical Reports Server (NTRS)

1975-01-01

A systems analysis of energy recovery from solid waste which demonstrates the feasibility of several processes for converting solid waste to an energy form is presented. The social, legal, environmental, and political factors are considered and recommendations made in regard to legislation and policy. A technical and economic evaluation of available and developing energy-recovery processes is given with emphasis on thermal decomposition and biodegradation. A pyrolysis process is suggested. The use of prepared solid waste as a fuel supplemental to coal is considered to be the most economic process for recovery of energy from solid waste. Markets are discussed with suggestions for improving market conditions and for developing market stability. A decision procedure is given to aid a community in deciding on its options in dealing with solid waste.

Nanocomposites Based on Biodegradable Polymers.

PubMed

Armentano, Ilaria; Puglia, Debora; Luzi, Francesca; Arciola, Carla Renata; Morena, Francesco; Martino, Sabata; Torre, Luigi

2018-05-15

In the present review paper, our main results on nanocomposites based on biodegradable polymers (on a time scale from 2010 to 2018) are reported. We mainly focused our attention on commercial biodegradable polymers, which we mixed with different nanofillers and/or additives with the final aim of developing new materials with tunable specific properties. A wide list of nanofillers have been considered according to their shape, properties, and functionalization routes, and the results have been discussed looking at their roles on the basis of different adopted processing routes (solvent-based or melt-mixing processes). Two main application fields of nanocomposite based on biodegradable polymers have been considered: the specific interaction with stem cells in the regenerative medicine applications or as antimicrobial materials and the active role of selected nanofillers in food packaging applications have been critically revised, with the main aim of providing an overview of the authors' contribution to the state of the art in the field of biodegradable polymeric nanocomposites.

7 CFR 3201.8 - Determining life cycle costs, environmental and health benefits, and performance.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Test Method for Determining Aerobic Biodegradation of Plastic Materials Under Controlled Composting Conditions”; (2) D5864“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants...“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants or Their Components...

7 CFR 2902.8 - Determining life cycle costs, environmental and health benefits, and performance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... for Determining Aerobic Biodegradation of Plastic Materials Under Controlled Composting Conditions”; (2) D5864“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants or...“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants or Their Components...

7 CFR 3201.8 - Determining life cycle costs, environmental and health benefits, and performance.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Test Method for Determining Aerobic Biodegradation of Plastic Materials Under Controlled Composting Conditions”; (2) D5864“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants...“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants or Their Components...

7 CFR 3201.8 - Determining life cycle costs, environmental and health benefits, and performance.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Test Method for Determining Aerobic Biodegradation of Plastic Materials Under Controlled Composting Conditions”; (2) D5864“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants...“Standard Test Method for Determining the Aerobic Aquatic Biodegradation of Lubricants or Their Components...

Greenhouse gas emissions from the treatment of household plastic containers and packaging: replacement with biomass-based materials.

PubMed

Yano, Junya; Hirai, Yasuhiro; Sakai, Shin-ichi; Tsubota, Jun

2014-04-01

The purpose of this study was to quantify the life-cycle greenhouse gas (GHG) emissions reduction that could be achieved by replacement of fossil-derived materials with biodegradable, biomass-based materials for household plastic containers and packaging, considering a variety of their treatment options. The biomass-based materials were 100% polylactide or a combination of polybutylene succinate adipate and polylactide. A scenario analysis was conducted considering alternative recycling methods. Five scenarios were considered: two for existing fossil-derived materials (the current approach in Japan) and the three for biomass-based materials. Production and waste disposal of 1 m(3) of plastic containers and packaging from households was defined as the functional unit. The results showed that replacement of fossil-derived materials with biomass-based materials could reduce life-cycle GHG emissions by 14-20%. Source separation and recycling should be promoted. When the separate collection ratio reached 100%, replacement with biomass-based materials could potentially reduce GHG emissions by 31.9%. Food containers are a priority for replacement, because they alone could reduce GHG emissions by 10%. A recycling system for biomass-based plastics must be carefully designed, considering aspects such as the transition period from fossil-derived plastics to biomass-based plastics.

Effect of degrading yellow oxo-biodegradable low-density polyethylene films to water quality

NASA Astrophysics Data System (ADS)

Requejo, B. A.; Pajarito, B. B.

2017-05-01

Polyethylene (PE) contributes largely to plastic wastes that are disposed in aquatic environment as a consequence of its widespread use. In this study, yellow oxo-biodegradable low-density PE films were immersed in deionized water at 50°C for 49 days. Indicators of water quality: pH, oxidation-reduction potential, turbidity, and total dissolved solids (TDS), were monitored at regular intervals. It was observed that pH initially rises and then slowly decreases with time, oxidation-reduction potential decreases then slowly increases with time, turbidity rises above the control at varied rates, and TDS increases abruptly and rises at a hindered rate. Moreover, the films potentially leach out lead chromate. The results imply that degrading oxo-biodegradable LDPE films results to significant reduction of water quality.

ANAEROBIC BIODEGRADATION OF NITROGEN-SUBSTITUTED AND SULFONATED BENZENE AQUIFER CONTAMINANTS (JOURNAL)

EPA Science Inventory

A literature survey of ground water contaminants indicated that aquifers are repositories for hazardous wastes, including N- and 5-substituted benzene derivatives. We therefore examined the susceptibility of several anilines, benzamides, benenesulfonic acids and benenesulfonamide...

Biodegradation of Used Motor Oil in Soil Using Organic Waste Amendments

PubMed Central

Abioye, O. P.; Agamuthu, P.; Abdul Aziz, A. R.

2012-01-01

Soil and surface water contamination by used lubricating oil is a common occurrence in most developing countries. This has been shown to have harmful effects on the environment and human beings at large. Bioremediation can be an alternative green technology for remediation of such hydrocarbon-contaminated soil. Bioremediation of soil contaminated with 5% and 15% (w/w) used lubricating oil and amended with 10% brewery spent grain (BSG), banana skin (BS), and spent mushroom compost (SMC) was studied for a period of 84 days, under laboratory condition. At the end of 84 days, the highest percentage of oil biodegradation (92%) was recorded in soil contaminated with 5% used lubricating oil and amended with BSG, while only 55% of oil biodegradation was recorded in soil contaminated with 15% used lubricating oil and amended with BSG. Results of first-order kinetic model to determine the rate of biodegradation of used lubricating oil revealed that soil amended with BSG recorded the highest rate of oil biodegradation (0.4361 day−1) in 5% oil pollution, while BS amended soil recorded the highest rate of oil biodegradation (0.0556 day−1) in 15% oil pollution. The results of this study demonstrated the potential of BSG as a good substrate for enhanced remediation of hydrocarbon contaminated soil at low pollution concentration. PMID:22919502

Biodegradable Microfluidic Scaffolds for Vascular Tissue Engineering

DTIC Science & Technology

2005-01-01

Engineering DISTRIBUTION: Approved for public release, distribution unlimited This paper is part of the following report: TITLE: Materials Research...Society Symposium Proceedings. Volume 845, 2005. Nanoscale Materials Science in Biology and Medicine, Held in Boston, MA on 28 November-2 December 2004...Symp. Proc. Vol. 845 © 2005 Materials Research Society AA1.6 Biodegradable Microfluidic Scaffolds for Vascular Tissue Engineering C. J. Bettinger" 3

A Study of Rapid Biodegradation of Oily Wastes through Composting.

DTIC Science & Technology

1979-10-01

effective method for large-scale composting of organic wastes. This research project was based on the principles of the forced aeration technique. The...carbon results in heat loss and subsequent reduction in effectiveness of pathogen destruction. It is therefore desirable to maintain the C/N ratio at a...investigated the effect of composting on the degradation of hydrocarbons in sewage sludge. Sludge extracts were fractionated into classes of compounds and a

Disposal of Kitchen Waste from High Rise Apartment

NASA Astrophysics Data System (ADS)

Ori, Kirki; Bharti, Ajay; Kumar, Sunil

2017-09-01

The high rise building has numbers of floor and rooms having variety of users or tenants for residential purposes. The huge quantities of heterogenous mixtures of domestic food waste are generated from every floor of the high rise residential buildings. Disposal of wet and biodegradable domestic kitchen waste from high rise buildings are more expensive in regards of collection and vertical transportation. This work is intended to address the technique to dispose of the wet organic food waste from the high rise buildings or multistory building at generation point with the advantage of gravity and vermicomposting technique. This innovative effort for collection and disposal of wet organic solid waste from high rise apartment is more economical and hygienic in comparison with present system of disposal.

Food Waste to Energy: An Overview of Sustainable Approaches for Food Waste Management and Nutrient Recycling

PubMed Central

Paritosh, Kunwar; Kushwaha, Sandeep K.; Yadav, Monika; Pareek, Nidhi; Chawade, Aakash

2017-01-01

Food wastage and its accumulation are becoming a critical problem around the globe due to continuous increase of the world population. The exponential growth in food waste is imposing serious threats to our society like environmental pollution, health risk, and scarcity of dumping land. There is an urgent need to take appropriate measures to reduce food waste burden by adopting standard management practices. Currently, various kinds of approaches are investigated in waste food processing and management for societal benefits and applications. Anaerobic digestion approach has appeared as one of the most ecofriendly and promising solutions for food wastes management, energy, and nutrient production, which can contribute to world's ever-increasing energy requirements. Here, we have briefly described and explored the different aspects of anaerobic biodegrading approaches for food waste, effects of cosubstrates, effect of environmental factors, contribution of microbial population, and available computational resources for food waste management researches. PMID:28293629

Food Waste to Energy: An Overview of Sustainable Approaches for Food Waste Management and Nutrient Recycling.

PubMed

Paritosh, Kunwar; Kushwaha, Sandeep K; Yadav, Monika; Pareek, Nidhi; Chawade, Aakash; Vivekanand, Vivekanand

2017-01-01

Food wastage and its accumulation are becoming a critical problem around the globe due to continuous increase of the world population. The exponential growth in food waste is imposing serious threats to our society like environmental pollution, health risk, and scarcity of dumping land. There is an urgent need to take appropriate measures to reduce food waste burden by adopting standard management practices. Currently, various kinds of approaches are investigated in waste food processing and management for societal benefits and applications. Anaerobic digestion approach has appeared as one of the most ecofriendly and promising solutions for food wastes management, energy, and nutrient production, which can contribute to world's ever-increasing energy requirements. Here, we have briefly described and explored the different aspects of anaerobic biodegrading approaches for food waste, effects of cosubstrates, effect of environmental factors, contribution of microbial population, and available computational resources for food waste management researches.

Critical evaluation of biodegradable polymers used in nanodrugs

PubMed Central

Marin, Edgar; Briceño, Maria Isabel; Caballero-George, Catherina

2013-01-01

Use of biodegradable polymers for biomedical applications has increased in recent decades due to their biocompatibility, biodegradability, flexibility, and minimal side effects. Applications of these materials include creation of skin, blood vessels, cartilage scaffolds, and nanosystems for drug delivery. These biodegradable polymeric nanoparticles enhance properties such as bioavailability and stability, and provide controlled release of bioactive compounds. This review evaluates the classification, synthesis, degradation mechanisms, and biological applications of the biodegradable polymers currently being studied as drug delivery carriers. In addition, the use of nanosystems to solve current drug delivery problems are reviewed. PMID:23990720

Biodegradable Polymers

PubMed Central

Vroman, Isabelle; Tighzert, Lan

2009-01-01

Biodegradable materials are used in packaging, agriculture, medicine and other areas. In recent years there has been an increase in interest in biodegradable polymers. Two classes of biodegradable polymers can be distinguished: synthetic or natural polymers. There are polymers produced from feedstocks derived either from petroleum resources (non renewable resources) or from biological resources (renewable resources). In general natural polymers offer fewer advantages than synthetic polymers. The following review presents an overview of the different biodegradable polymers that are currently being used and their properties, as well as new developments in their synthesis and applications.

Whose butt is it? tobacco industry research about smokers and cigarette butt waste

PubMed Central

Novotny, Thomas E

2011-01-01

Background Cigarette filters are made of non-biodegradable cellulose acetate. As much as 766 571 metric tons of butts wind up as litter worldwide per year. Numerous proposals have been made to prevent or mitigate cigarette butt pollution, but none has been effective; cigarette butts are consistently found to be the single most collected item in beach clean-ups and litter surveys. Methods We searched the Legacy Tobacco Documents Library (http://legacy.library.ucsf.edu) and http://tobaccodocuments.org using a snowball strategy beginning with keywords (eg, ‘filter’, ‘biodegradable’, ‘butts’). Data from approximately 680 documents, dated 1959–2006, were analysed using an interpretive approach. Results The tobacco industry has feared being held responsible for cigarette litter for more than 20 years. Their efforts to avoid this responsibility included developing biodegradable filters, creating anti-litter campaigns, and distributing portable and permanent ashtrays. They concluded that biodegradable filters would probably encourage littering and would not be marketable, and that smokers were defensive about discarding their tobacco butts and not amenable to anti-litter efforts. Conclusions Tobacco control and environmental advocates should develop partnerships to compel the industry to take financial and practical responsibility for cigarette butt waste. PMID:21504919

Impact comparative study of phone carcasses behavior by FEM

NASA Astrophysics Data System (ADS)

Constantin, Cărăuşu; Plăvănescu, Simona; Dumitru, Nedelcu

2015-07-01

A constant concern of scientific research is based on plastics replace with biodegradable materials that reduce the adverse impact of waste on the environment. A biodegradable material that arouses interest lately is Arboform which is made of lignin, a component of wood and woody plants. Replacing plastic with Arboform in carrying components of products requires technical and economic studies on the implications of such replacement. Numerical simulation methods are a fast and economical way of analyzing the behavior of a product in various mechanical, thermal, electromagnetic and so on. The paper presents comparative results of numerical simulation using the software package SolidWorks impact behavior through the “Drop Test” of half shells made of High Density Polyethylene (HDPE) and of the Arboform LV3 Nature. Simulation watched the half-carcass behavior in three cases of accidental impact, “head”, “corner” and the “back side”. We analyzed the size and location of the maximum voltage and maximum deformation resulting from impact. Simulations have shown for all three cases a maximum voltage increase when using Arboform to use PEDH 93% for impact “forward” and “corner” and only 48.77% “back side” impact. If the maximum displacement, it increasing from carcasses of Arboform 4% for impact “head” and 6% for impact “corner”, but fell by 2.7% for the “back side” impact. The significant increase of stress can be attributed to the higher density of Arboform to PEDH, which led to different weights of the two half-carcasses.

Biodegradation of waste greases and biochemical properties of a novel lipase from Pseudomonas synxantha PS1.

PubMed

Cai, Xianghai; Chen, Siqi; Yang, Hong; Wang, Wei; Lin, Lin; Shen, Yaling; Wei, Wei; Wei, Dong-Zhi

2016-07-01

A lipase-producing bacterial strain was isolated from oil-well-produced water in Shengli oilfield (Shandong province, China) and was identified as Pseudomonas synxantha by 16S rDNA sequence analysis (named Pseudomonas synxantha PS1). Strain PS1 showed a maximum lipase activity of 10.8 U/mL after culturing for 48 h at 30 °C, with lactose (4 g/L) as carbon source, tryptone (8 g/L) as nitrogen source, olive oil (0.5%, v/v) as inductor, and the initial pH 8.0. Meanwhile, the lipase gene from P. synxantha PS1 was cloned and expressed in Escherichia coli BL21 with the vector pET28a. The novel gene (lipPS1) has an open reading frame of 1425 bp and encodes a 474 aa lipase (LipPS1) sharing the most identity (87%) with the lipase in Pseudomonas fluorescens. LipPS1 preferably acted on substrates with a long chain (C10-C18) of fatty acids. The optimum pH and temperature of the recombinant enzyme were 8.0 and 40 °C, respectively, towards the optimum substrate p-nitrophenyl palmitate. The LipPS1 showed remarkable stability under alkaline conditions and was stable at pH 7.0-10.0 (retaining more than 60% activity). From the organic solvents tests, the lipase was activated by 15% (v/v) methanol (112%), 15% ethanol (127%), and 15% n-butyl alcohol (116%). LipPS1 presented strong biodegradability of waste grease; 93% of waste grease was hydrolyzed into fatty acid after 12 h at 30 °C. This is the first report of the lipase activity and lipase gene obtained from P. synxantha (including wild strain and recombinant strain) and of the recombinant LipPS1 with the detailed enzymatic properties. Also a preliminary study of the biodegradability of waste greases shows the potential value in industry applications.

Durability of Starch Based Biodegradable Plastics Reinforced with Manila Hemp Fibers.

PubMed

Ochi, Shinji

2011-02-25

The biodegradability of Manila hemp fiber reinforced biodegradable plastics was studied for 240 days in a natural soil and 30 days in a compost soil. After biodegradability tests, weights were measured and both tensile strength tests and microscopic observation were performed to evaluate the biodegradation behavior of the composites. The results indicate that the tensile strength of the composites displays a sharp decrease for up to five days, followed by a gradual decrease. The weight loss and the reduction in tensile strength of biodegradable composite materials in the compost soil are both significantly greater than those buried in natural soil. The biodegradability of these composites is enhanced along the lower portion because this area is more easily attacked by microorganisms.

Durability of Starch Based Biodegradable Plastics Reinforced with Manila Hemp Fibers

PubMed Central

Ochi, Shinji

2011-01-01

The biodegradability of Manila hemp fiber reinforced biodegradable plastics was studied for 240 days in a natural soil and 30 days in a compost soil. After biodegradability tests, weights were measured and both tensile strength tests and microscopic observation were performed to evaluate the biodegradation behavior of the composites. The results indicate that the tensile strength of the composites displays a sharp decrease for up to five days, followed by a gradual decrease. The weight loss and the reduction in tensile strength of biodegradable composite materials in the compost soil are both significantly greater than those buried in natural soil. The biodegradability of these composites is enhanced along the lower portion because this area is more easily attacked by microorganisms. PMID:28880000

Mercury determination in non- and biodegradable materials by cold vapor capacitively coupled plasma microtorch atomic emission spectrometry.

PubMed

Frentiu, Tiberiu; Mihaltan, Alin I; Ponta, Michaela; Darvasi, Eugen; Frentiu, Maria; Cordos, Emil

2011-10-15

A new analytical system consisting of a low power capacitively coupled plasma microtorch (20 W, 13.56 MHz, 150 ml min(-1) Ar) and a microspectrometer was investigated for the Hg determination in non- and biodegradable materials by cold-vapor generation, using SnCl(2) reductant, and atomic emission spectrometry. The investigated miniaturized system was used for Hg determination in recyclable plastics from electronic equipments and biodegradable materials (shopping bags of 98% biodegradable polyethylene and corn starch) with the advantages of easy operation and low analysis costs. Samples were mineralized in HNO(3)-H(2)SO(4) mixture in a high-pressure microwave system. The detection limits of 0.05 ng ml(-1) or 0.08 μg g(-1) in solid sample were compared with those reported for other analytical systems. The method precision was 1.5-9.4% for Hg levels of 1.37-13.9 mg kg(-1), while recovery in two polyethylene certified reference materials in the range 98.7 ± 4.5% (95% confidence level). Copyright © 2011 Elsevier B.V. All rights reserved.

Changes in organic - C, N, P and K and enzyme activities in vermicompost of biodegradable organic wastes under liming and microbial inoculants.

PubMed

Pramanik, P; Ghosh, G K; Ghosal, P K; Banik, P

2007-09-01

The aim of this work was to study the effect of different organic wastes, viz. cow dung, grass, aquatic weeds and municipal solid waste with lime and microbial inoculants on chemical and biochemical properties of vermicompost. Cow dung was the best substrate for vermicomposting. Application of lime (5 g/kg) and inoculation of microorganisms increased the nutrient content in vermicompost and also phosphatases and urease activities. Bacillus polymyxa, the free-living N-fixer, increased N-content of vermicompost significantly (p < or = 0.01) as compared to other inoculants.

Skatole biodegradation via isolates from swine manure

USDA-ARS?s Scientific Manuscript database

Animal waste disposal and odor control have become a major issue for animal production facilities. As an attempt to improve efficiency and profit margins, many livestock operations have become large concentrated rearing facilities. As a result, many concerns over potentially adverse environmental ...

Aerobic Biodegradation of Oily Wastes: A Field Guide For Federal On-scene Coordinators

EPA Pesticide Factsheets

Intentionally limited in scope to best serve the requirements of the Region 6 Oil Program, this field guide consists of three parts complemented by appendices. Helps evaluate environment and consider factors, existing regulations/policies, operation issues

Mechanical Characteristics, In Vitro Degradation, Cytotoxicity, and Antibacterial Evaluation of Zn-4.0Ag Alloy as a Biodegradable Material

PubMed Central

Li, Ping; Schille, Christine; Schweizer, Ernst; Rupp, Frank; Heiss, Alexander; Legner, Claudia; Klotz, Ulrich E.; Geis-Gerstorfer, Jürgen

2018-01-01

Zn-based biodegradable metallic materials have been regarded as new potential biomaterials for use as biodegradable implants, mainly because of the ideal degradation rate compared with those of Mg-based alloys and Fe-based alloys. In this study, we developed and investigated a novel Zn-4 wt % Ag alloy as a potential biodegradable metal. A thermomechanical treatment was applied to refine the microstructure and, consequently, to improve the mechanical properties, compared to pure Zn. The yield strength (YS), ultimate tensile strength (UTS) and elongation of the Zn-4Ag alloy are 157 MPa, 261 MPa, and 37%, respectively. The corrosion rate of Zn-4Ag calculated from released Zn ions in DMEM extracts is approximately 0.75 ± 0.16 μg cm–2 day–1, which is higher than that of pure Zn. In vitro cytotoxicity tests showed that the Zn-4Ag alloy exhibits acceptable toxicity to L929 and Saos-2 cells, and could effectively inhibit initial bacteria adhesion. This study shows that the Zn-4Ag exhibits excellent mechanical properties, predictable degradation behavior, acceptable biocompatibility, and effective antibacterial properties, which make it a candidate biodegradable material. PMID:29518938

Plastics recycling: challenges and opportunities.

PubMed

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-07-27

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades.

Plastics recycling: challenges and opportunities

PubMed Central

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-01-01

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades. PMID:19528059

Key parameters in testing biodegradation of bio-based materials in soil.

PubMed

Briassoulis, D; Mistriotis, A

2018-09-01

Biodegradation of plastics in soil is currently tested by international standard testing methods (e.g. ISO 17556-12 or ASTM D5988-12). Although these testing methods have been developed for plastics, it has been shown in project KBBPPS that they can be extended also to lubricants with small modifications. Reproducibility is a critical issue regarding biodegradation tests in the laboratory. Among the main testing variables are the soil types and nutrients available (mainly nitrogen). For this reason, the effect of the soil type on the biodegradation rates of various bio-based materials (cellulose and lubricants) was tested for five different natural soil types (loam, loamy sand, clay, clay-loam, and silt-loam organic). It was shown that use of samples containing 1 g of C in a substrate of 300 g of soil with the addition of 0.1 g of N as nutrient strongly improves the reproducibility of the test making the results practically independent of the soil type with the exception of the organic soil. The sandy soil was found to need addition of higher amount of nutrients to exhibit similar biodegradation rates as those achieved with the other soil types. Therefore, natural soils can be used for Standard biodegradation tests of bio-based materials yielding reproducible results with the addition of appropriate nutrients. Copyright © 2018 Elsevier Ltd. All rights reserved.

Enhancement of poly(3-hydroxybutyrate) thermal and processing stability using a bio-waste derived additive.

PubMed

Persico, Paola; Ambrogi, Veronica; Baroni, Antonio; Santagata, Gabriella; Carfagna, Cosimo; Malinconico, Mario; Cerruti, Pierfrancesco

2012-12-01

Poly(3-hydroxybutyrate) (PHB) is a biodegradable polymer, whose applicability is limited by its brittleness and narrow processing window. In this study a pomace extract (EP), from the bio-waste of winery industry, was used as thermal and processing stabilizer for PHB, aimed to engineer a totally bio-based system. The results showed that EP enhanced the thermal stability of PHB, which maintained high molecular weights after processing. This evidence was in agreement with the slower decrease in viscosity over time observed by rheological tests. EP also affected the melt crystallization kinetics and the overall crystallinity extent. Finally, dynamic mechanical and tensile tests showed that EP slightly improved the polymer ductility. The results are intriguing, in view of the development of sustainable alternatives to synthetic polymer additives, thus increasing the applicability of bio-based materials. Moreover, the reported results demonstrated the feasibility of the conversion of an agro-food by-product into a bio-resource in an environmentally friendly and cost-effective way. Copyright © 2012 Elsevier B.V. All rights reserved.

Biosorption of chromium (VI) from aqueous solutions and ANN modelling.

PubMed

Nag, Soma; Mondal, Abhijit; Bar, Nirjhar; Das, Sudip Kumar

2017-08-01

The use of sustainable, green and biodegradable natural wastes for Cr(VI) detoxification from the contaminated wastewater is considered as a challenging issue. The present research is aimed to assess the effectiveness of seven different natural biomaterials, such as jackfruit leaf, mango leaf, onion peel, garlic peel, bamboo leaf, acid treated rubber leaf and coconut shell powder, for Cr(VI) eradication from aqueous solution by biosorption process. Characterizations were conducted using SEM, BET and FTIR spectroscopy. The effects of operating parameters, viz., pH, initial Cr(VI) ion concentration, adsorbent dosages, contact time and temperature on metal removal efficiency, were studied. The biosorption mechanism was described by the pseudo-second-order model and Langmuir isotherm model. The biosorption process was exothermic, spontaneous and chemical (except garlic peel) in nature. The sequence of adsorption capacity was mango leaf > jackfruit leaf > acid treated rubber leaf > onion peel > bamboo leaf > garlic peel > coconut shell with maximum Langmuir adsorption capacity of 35.7 mg g -1 for mango leaf. The treated effluent can be reused. Desorption study suggested effective reuse of the adsorbents up to three cycles, and safe disposal method of the used adsorbents suggested biodegradability and sustainability of the process by reapplication of the spent adsorbent and ultimately leading towards zero wastages. The performances of the adsorbents were verified with wastewater from electroplating industry. The scale-up study reported for industrial applications. ANN modelling using multilayer perception with gradient descent (GD) and Levenberg-Marquart (LM) algorithm had been successfully used for prediction of Cr(VI) removal efficiency. The study explores the undiscovered potential of the natural waste materials for sustainable existence of small and medium sector industries, especially in the third world countries by protecting the environment by eco-innovation.

Biodegradability of PP/HMSPP and natural and synthetic polymers blends in function of gamma irradiation degradation

NASA Astrophysics Data System (ADS)

Cardoso, Elisabeth C. L.; Scagliusi, Sandra R.; Lima, Luis F. C. P.; Bueno, Nelson R.; Brant, Antonio J. C.; Parra, Duclerc F.; Lugão, Ademar B.

2014-01-01

Polymers are used for numerous applications in different industrial segments, generating enormous quantities of discarding in the environment. Polymeric materials composites account for an estimated from 20 to 30% total volume of solid waste. Polypropylene (PP) undergoes crosslinking and extensive main chain scissions when submitted to ionizing irradiation; as one of the most widely used linear hydrocarbon polymers, PP, made from cheap petrochemical feed stocks, shows easy processing leading it to a comprehensive list of finished products. Consequently, there is accumulation in the environment, at 25 million tons per year rate, since polymeric products are not easily consumed by microorganisms. PP polymers are very bio-resistant due to involvement of only carbon atoms in main chain with no hydrolysable functional group. Several possibilities have been considered to minimize the environmental impact caused by non-degradable plastics, subjecting them to: physical, chemical and biological degradation or combination of all these due to the presence of moisture, air, temperature, light, high energy radiation or microorganisms. There are three main classes of biodegradable polymers: synthetic polymers, natural polymers and blends of polymers in which one or more components are readily consumed by microorganisms. This work aims to biodegradability investigation of a PP/HMSPP (high melt strength polypropylene) blended with sugarcane bagasse, PHB (poly-hydroxy-butyrate) and PLA (poly-lactic acid), both synthetic polymers, at a 10% level, subjected to gamma radiation at 50, 100, 150 and 200 kGy doses. Characterization will comprise IR, DSC, TGA, OIT and Laboratory Soil Burial Test (LSBT).

Algae and their biodegradation effects on building materials in the Ostrava industrial agglomeration

NASA Astrophysics Data System (ADS)

Vojtková, H.

2017-10-01

Microorganisms cause changes in the building stone, which reduce its usable life and reliability. Microalgae make important parts of the biodegradation consortia of microorganisms on the surface of building materials. Via their metabolites, microalgae affect the stability of mineral components and thus lead to the material destruction. The aim of the paper was to identify aerophytic microalgae on the surface of engineering structures in the Ostrava agglomeration, and to describe the basic interactions between such microorganisms and the building materials, which may lead to the destruction of the materials.

Prediction of the compression ratio for municipal solid waste using decision tree.

PubMed

Heshmati R, Ali Akbar; Mokhtari, Maryam; Shakiba Rad, Saeed

2014-01-01

The compression ratio of municipal solid waste (MSW) is an essential parameter for evaluation of waste settlement and landfill design. However, no appropriate model has been proposed to estimate the waste compression ratio so far. In this study, a decision tree method was utilized to predict the waste compression ratio (C'c). The tree was constructed using Quinlan's M5 algorithm. A reliable database retrieved from the literature was used to develop a practical model that relates C'c to waste composition and properties, including dry density, dry weight water content, and percentage of biodegradable organic waste using the decision tree method. The performance of the developed model was examined in terms of different statistical criteria, including correlation coefficient, root mean squared error, mean absolute error and mean bias error, recommended by researchers. The obtained results demonstrate that the suggested model is able to evaluate the compression ratio of MSW effectively.

Characterization of Volume F Trash from the Three FY11 STS Missions: Trash Weights and Categorization and Microbial Characterization

NASA Technical Reports Server (NTRS)

Strayer, Richard F.; Hummerick, Mary E.; Richards, Jeffrey T.; McCoy, LaShelle E.; Roberts, Michael S.; Wheller, Raymond M.

2011-01-01

The project reported here provides microbial characterization support to the Waste Management Systems (WMS) element of NASA's Life Support and Habitation Systems (LSHS) program. Conventional microbiological methods were used to detect and enumerate microorganisms in STS Volume F Compartment trash for three shuttle missions: STS 133, 134, and 135. This trash was usually made available within 2 days of landing at KSC. The Volume F bag was weighed, opened and the contents were cataloged and placed into categories: personal hygiene items - inclUding EVA maximum absorbent garments (MAGs) and Elbow packs (daily toilet wipes, etc), drink containers, food waste (and containers), office waste (paper), and packaging materials - plastic film and duct tape. The average wet trash generation rate for the three STS missions was 0.362 % 0.157 kgwet crew 1 d-1 . This was considerably lower and more variable than the average rate for 4 STS missions reported for FY10. Trash subtotals by category: personal hygiene wastes, 56%; drink items, 11 %; food wastes, 18%; office waste, 3%; and plastic film, 12%. These wastes have an abundance of easily biodegraded compounds that can support the growth of microorganisms. Microbial characterization of trash showed that large numbers of bacteria and fungi have taken advantage of this readily available nutrient source to proliferate. Exterior and interior surfaces of plastic film bags containing trash were sampled and counts of cultivatable microbes were generally low and mostly occurred on trash bundles within the exterior trash bags. Personal hygiene wastes, drink containers, and food wastes and packaging all contained high levels of, mostly, aerobic heterotrophic bacteria and lower levels of yeasts and molds. Isolates from plate count media were obtained and identified .and were mostly aerobic heterotrophs with some facultative anaerobes. These are usually considered common environmental isolates on Earth. However, several pathogens were also isolated: Staphylococcus aureus and Escherichia coli.

Investigation of biosolids degradation under flooded environments for use in underwater cover designs for mine tailing remediation.

PubMed

Jia, Yu; Nason, Peter; Maurice, Christian; Alakangas, Lena; Öhlander, Björn

2015-07-01

To evaluate the potential suitability of digested sewage sludge (frequently termed biosolids) for use as underwater cover material for mine waste tailings, the degradability of biosolids at 20 - 22 °C under flooded anaerobic conditions was evaluated during incubation for 230 days. Leaching of elements from the flooded anaerobic system was also evaluated. Biosolid degradation was confirmed by the generation and accumulation of CH4 and CO2. Specifically, approximately 1.65 mmoL gas/g biosolids was generated as a result of incubation, corresponding to degradation of 7.68% of the organic matter, and the residue was stable at the end of the laboratory experiment. Under field conditions in northern Sweden, it is expected that the degradation rate will be much slower than that observed in the present study (Nason et al. Environ Earth Sci 70:30933105, 2013). Although the majority of biosolid fractions (>92%) were shown to be recalcitrant during the incubation period, long-term monitoring of further degradability of residue is necessary. The leaching results showed that most of the metals and metalloids leached from the biosolids at day 230 were below the limit value for non-hazardous waste, although Ni was the only element approximately three times higher than the limit value for inert material at the landfill site. In conclusion, biosolids have potential for use as covering material for underwater storage of tailings based on their biodegradability and leaching of elements.

Municipal solid waste landfills harbor distinct microbiomes

USGS Publications Warehouse

Stamps, Blake W.; Lyles, Christopher N.; Suflita, Joseph M.; Masoner, Jason R.; Cozzarelli, Isabelle M.; Kolpin, Dana W.; Stevenson, Bradley S.

2016-01-01

Landfills are the final repository for most of the discarded material from human society and its “built environments.” Microorganisms subsequently degrade this discarded material in the landfill, releasing gases (largely CH4 and CO2) and a complex mixture of soluble chemical compounds in leachate. Characterization of “landfill microbiomes” and their comparison across several landfills should allow the identification of environmental or operational properties that influence the composition of these microbiomes and potentially their biodegradation capabilities. To this end, the composition of landfill microbiomes was characterized as part of an ongoing USGS national survey studying the chemical composition of leachates from 19 non-hazardous landfills across 16 states in the continental U.S. The landfills varied in parameters such as size, waste composition, management strategy, geography, and climate zone. The diversity and composition of bacterial and archaeal populations in leachate samples were characterized by 16S rRNA gene sequence analysis, and compared against a variety of physical and chemical parameters in an attempt to identify their impact on selection. Members of the Epsilonproteobacteria, Gammaproteobacteria, Clostridia, and candidate division OP3 were the most abundant. The distribution of the observed phylogenetic diversity could best be explained by a combination of variables and was correlated most strongly with the concentrations of chloride and barium, rate of evapotranspiration, age of waste, and the number of detected household chemicals. This study illustrates how leachate microbiomes are distinct from those of other natural or built environments, and sheds light on the major selective forces responsible for this microbial diversity.

Municipal Solid Waste Landfills Harbor Distinct Microbiomes

PubMed Central

Stamps, Blake W.; Lyles, Christopher N.; Suflita, Joseph M.; Masoner, Jason R.; Cozzarelli, Isabelle M.; Kolpin, Dana W.; Stevenson, Bradley S.

2016-01-01

Landfills are the final repository for most of the discarded material from human society and its “built environments.” Microorganisms subsequently degrade this discarded material in the landfill, releasing gases (largely CH4 and CO2) and a complex mixture of soluble chemical compounds in leachate. Characterization of “landfill microbiomes” and their comparison across several landfills should allow the identification of environmental or operational properties that influence the composition of these microbiomes and potentially their biodegradation capabilities. To this end, the composition of landfill microbiomes was characterized as part of an ongoing USGS national survey studying the chemical composition of leachates from 19 non-hazardous landfills across 16 states in the continental U.S. The landfills varied in parameters such as size, waste composition, management strategy, geography, and climate zone. The diversity and composition of bacterial and archaeal populations in leachate samples were characterized by 16S rRNA gene sequence analysis, and compared against a variety of physical and chemical parameters in an attempt to identify their impact on selection. Members of the Epsilonproteobacteria, Gammaproteobacteria, Clostridia, and candidate division OP3 were the most abundant. The distribution of the observed phylogenetic diversity could best be explained by a combination of variables and was correlated most strongly with the concentrations of chloride and barium, rate of evapotranspiration, age of waste, and the number of detected household chemicals. This study illustrates how leachate microbiomes are distinct from those of other natural or built environments, and sheds light on the major selective forces responsible for this microbial diversity. PMID:27148222

Biodegradable nanoparticles for gene therapy technology

NASA Astrophysics Data System (ADS)

Hosseinkhani, Hossein; He, Wen-Jie; Chiang, Chiao-Hsi; Hong, Po-Da; Yu, Dah-Shyong; Domb, Abraham J.; Ou, Keng-Liang

2013-07-01

Rapid propagations in materials technology together with biology have initiated great hopes in the possibility of treating many diseases by gene therapy technology. Viral and non-viral gene carriers are currently applied for gene delivery. Non-viral technology is safe and effective for the delivery of genetic materials to cells and tissues. Non-viral systems are based on plasmid expression containing a gene encoding a therapeutic protein and synthetic biodegradable nanoparticles as a safe carrier of gene. Biodegradable nanoparticles have shown great interest in drug and gene delivery systems as they are easy to be synthesized and have no side effect in cells and tissues. This review provides a critical view of applications of biodegradable nanoparticles on gene therapy technology to enhance the localization of in vitro and in vivo and improve the function of administered genes.

Wood-plastic composites as promising green-composites for automotive industries!

PubMed

Ashori, Alireza

2008-07-01

Wood-plastic composite (WPC) is a very promising and sustainable green material to achieve durability without using toxic chemicals. The term WPCs refers to any composites that contain plant fiber and thermosets or thermoplastics. In comparison to other fibrous materials, plant fibers are in general suitable to reinforce plastics due to relative high strength and stiffness, low cost, low density, low CO2 emission, biodegradability and annually renewable. Plant fibers as fillers and reinforcements for polymers are currently the fastest-growing type of polymer additives. Since automakers are aiming to make every part either recyclable or biodegradable, there still seems to be some scope for green-composites based on biodegradable polymers and plant fibers. From a technical point of view, these bio-based composites will enhance mechanical strength and acoustic performance, reduce material weight and fuel consumption, lower production cost, improve passenger safety and shatterproof performance under extreme temperature changes, and improve biodegradability for the auto interior parts.

Heat treatment of organics for increasing anaerobic biodegradability. Annual progress report, June 1, 1976-May 31, 1977. Civil engineering technical report No. 222

DOE Office of Scientific and Technical Information (OSTI.GOV)

Healy, J.B. Jr.; Owen, W.F.; Stuckey, D.C.

1977-06-30

This report represents the results of the first year of study on the heat treatment of organics to increase its biodegradability by anaerobic bacteria for the microbial production of methane. The purpose of this study is to develop a means for increasing the yield and reducing the cost of methane, a useful energy source. The procedures being evaluated are heat treatment at temperatures up to 250/sup 0/C, under pH ranges of 1 to 13. Included in this report are results on: (1) lignocellulose digestion and acclimation to its products from heat treatment; (2) the fate of waste activated sludge andmore » its cellular nitrogenous compounds; and (3) the biodegradability of model compounds likely to be formed during heat treatment.« less

Modeling ready biodegradability of fragrance materials.

PubMed

Ceriani, Lidia; Papa, Ester; Kovarich, Simona; Boethling, Robert; Gramatica, Paola

2015-06-01

In the present study, quantitative structure activity relationships were developed for predicting ready biodegradability of approximately 200 heterogeneous fragrance materials. Two classification methods, classification and regression tree (CART) and k-nearest neighbors (kNN), were applied to perform the modeling. The models were validated with multiple external prediction sets, and the structural applicability domain was verified by the leverage approach. The best models had good sensitivity (internal ≥80%; external ≥68%), specificity (internal ≥80%; external 73%), and overall accuracy (≥75%). Results from the comparison with BIOWIN global models, based on group contribution method, show that specific models developed in the present study perform better in prediction than BIOWIN6, in particular for the correct classification of not readily biodegradable fragrance materials. © 2015 SETAC.

Processing and characterization of novel biobased and biodegradable materials

NASA Astrophysics Data System (ADS)

Pilla, Srikanth

Human society has benefited tremendously from the use of petroleum-based plastics. However, there are growing concerns with their adverse environmental impacts and volatile costs attributed to the skyrocketing oil prices. Additionally most of the petroleum-based polymers are non-biodegradable causing problems about their disposal. Thus, during the last couple of decades, scientists ail over the world have been focusing on developing new polymeric materials that are biobased and biodegradable, also termed as green plastics . This study aims to develop green materials based on polylactide (PLA) biopolymer that can be made from plants. Although PLA can provide important advantages in terms of sustainability and biodegradability, it has its own challenges such as high cost, brittleness, and narrow processing window. These challenges are addressed in this study by investigating both new material formulations and processes. To improve the material properties and control the material costs, PLA was blended with various fillers and modifiers. The types of fillers investigated include carbon nanotube (CNT) nanoparticles and various natural fibers such as pine-wood four, recycled-wood fibers and flax fiber. Using natural fibers as fillers for PLA can result in fully biodegradable and eco-friendly biocomposites. Also due to PLA's sensitivity to moisture and temperature, molecular degradation can occur during processing leading to inferior material properties. To address this issue, one of the approaches adopted by this study was to incorporate a multifunctional chain-extender into PLA, which increased the molecular weight of PLA thereby improving the material properties. To improve the processability and reduce the material cost, both microcellular injection molding and extrusion processes have been studied. The microcellular technology allows the materials to be processed at a lower temperature, which is attractive for thermo- and moisture-sensitive materials like PLA. They are also capable of mass-producing foamed plastics with less material and less energy. Injection-molded or extruded components based on a number of different formulations were characterized extensively using various techniques such as tensile testing, dynamical mechanical analysis, differential scanning calorimetry, thermogravimetric analysis, electron microscopy (scanning and transmission), and density and molecular weight measurement, etc. Ultimately, the composition-processing-structure-property relationships in five material systems have been established.

Biodegradable and biocompatible high elastic chitosan scaffold is cell-friendly both in vitro and in vivo

PubMed Central

Lin, Xianfeng; Yang, Lin; Wang, Qiang; Wang, Zhengke; Shan, Zhi; Li, Shengyun; Wang, Jiying; Fan, Shunwu; Hu, Qiaoling

2017-01-01

Biodegradable and biocompatible macromolecule chitosan has been favored for a variety of clinical applications. We reported herein the fabrication of a novel chitosan scaffold with high elasticity. This scaffold can be easily compressed and thus enable the insertion of such scaffold into surgical lesions during minimal invasive surgeries. In addition, this novel scaffold can restore its shape when released. We evidenced that this high elastic scaffold has better biocompatibility than traditional chitosan scaffold. Therefore, this new chitosan material might lead to the manufacture of a variety of novel biodegradable biomedical materials and devices. PMID:28103580

Biodegradation of disinfection byproducts as a potential removal process during aquifer storage recovery

USGS Publications Warehouse

Landmeyer, J.E.; Bradley, P.M.; Thomas, J.M.

2000-01-01

The biodegradation potential of two drinking water disinfection byproducts was investigated using aquifer materials obtained from approximately 100 and 200 meters below land surface in an aerobic aquifer system undergoing aquifer storage recovery of treated surface water. No significant biodegradation of a model trihalomethane compound, chloroform, was observed in aquifer microcosms under aerobic or anaerobic conditions. In contrast, between 16 and 27 percent mineralization of a radiolabeled model haloacetic acid compound, chloroacetic acid, was observed. These results indicate that although the potential for biodegradation of chloroacetic acid exists in deep aquifer systems, chloroform entrained within these aquifers or formed in situ will tend to persist. These results have important implications for water managers planning to meet anticipated lowered permissible levels of tri-halomethanes in drinking water.The biodegradation potential of two drinking water disinfection byproducts was investigated using aquifer materials obtained from approximately 100 and 200 meters below land surface in an aerobic aquifer system undergoing aquifer storage recovery of treated surface water. No significant biodegradation of a model trihalomethane compound, chloroform, was observed in aquifer microcosms under aerobic or anaerobic conditions. In contrast, between 16 and 27 percent mineralization of a radiolabeled model haloacetic acid compound, chloroacetic acid, was observed. These results indicate that although the potential for biodegradation of chloroacetic acid exists in deep aquifer systems, chloroform entrained within these aquifers or formed in situ will tend to persist. These results have important implications for water managers planning to meet anticipated lowered permissible levels of trihalomethanes in drinking water.Aquifer-storage-recovery injection water often contains disinfection byproducts. Results are presented from a study in which two model disinfection byproducts, chloroform and chloroacetic acid, were used to examine biodegradation by indigenous microorganisms. The recharge system studied was near Las Vegas, NV, where the aquifers are recharged artificially during the winter months. Microcosms were constructed using aquifer material recovered from two layers. Results showed that no significant biodegradation of chloroform occurred under aerobic or anaerobic conditions, but chloroacetic acid was biodegraded under both aerobic and anaerobic conditions.

Opportunities and challenges for the biodegradable magnesium alloys as next-generation biomaterials

PubMed Central

Ding, Wenjiang

2016-01-01

In recent years, biodegradable magnesium alloys emerge as a new class of biomaterials for tissue engineering and medical devices. Deploying biodegradable magnesium-based materials not only avoids a second surgical intervention for implant removal but also circumvents the long-term foreign body effect of permanent implants. However, these materials are often subjected to an uncontrolled and fast degradation, acute toxic responses and rapid structural failure presumably due to a localized, too rapid corrosion process. The patented Mg–Nd–Zn–based alloys (JiaoDa BioMg [JDBM]) have been developed in Shanghai Jiao Tong University in recent years. The alloy series exhibit lower biodegradation rate and homogeneous nanophasic degradation patterns as compared with other biodegradable Mg alloys. The in vitro cytotoxicity tests using various types of cells indicate excellent biocompatibility of JDBM. Finally, bone implants using JDBM-1 alloy and cardiovascular stents using JDBM-2 alloy have been successfully fabricated and in vivo long-term assessment via implantation in animal model have been performed. The results confirmed the reduced degradation rate in vivo, excellent tissue compatibility and long-term structural and mechanical durability. Thus, this novel Mg-alloy series with highly uniform nanophasic biodegradation represent a major breakthrough in the field and a promising candidate for manufacturing the next generation biodegradable implants. PMID:27047673

Application of landfill treatment approaches for stabilization of municipal solid waste.

PubMed

Bolyard, Stephanie C; Reinhart, Debra R

2016-09-01

This research sought to compare the effectiveness of three landfill enhanced treatment approaches aimed at removing releasable carbon and nitrogen after anaerobic landfilling including flushing with clean water (FB 1), leachate recirculation with ex-situ treatment (FB 2), and leachate recirculation with ex-situ treatment and in-situ aeration (FB 3). After extensive treatment of the waste in the FB scenarios, the overall solids and biodegradable fraction were reduced relative to the mature anaerobically treated waste. In terms of the overall degradation, aeration did not provide any advantage over flushing and anaerobic treatment. Flushing was the most effective approach at removing biodegradable components (i.e. cellulose and hemicellulose). Leachate quality improved for all FBs but through different mechanisms. A significant reduction in ammonia-nitrogen occurred in FB 1 and 3 due to flushing and aeration, respectively. The reduction of chemical oxygen demand (COD) in FB 1 was primarily due to flushing. Conversely, the reduction in COD in FBs 2 and 3 was due to oxidation and precipitation during Fenton's Reagent treatment. A mass balance on carbon and nitrogen revealed that a significant fraction still remained in the waste despite the additional treatment provided. Carbon was primarily converted biologically to CH4 and CO2 in the FBs or removed during treatment using Fenton's Reagent. The nitrogen removal occurred through leaching or biological conversion. These results show that under extensive treatment the waste and leachate characteristics did meet published stability values. The minimum stability values achieved were through flushing although FB 2 and 3 were able to improve leachate quality and solid waste characteristics but not to the same extent as FB 1. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis of low cost organometallic-type catalysts for their application in microbial fuel cell technology.

PubMed

Zerrouki, A; Salar-García, M J; Ortiz-Martínez, V M; Guendouz, S; Ilikti, H; de Los Ríos, A P; Hernández-Fernández, F J; Kameche, M

2018-03-05

Microbial fuel cells (MFCs) are a promising technology that generates electricity from several biodegradable substrates and wastes. The main drawback of these devices is the need of using a catalyst for the oxygen reduction reaction at the cathode, which makes the process relatively expensive. In this work, two low cost materials are tested as catalysts in MFCs. A novel iron complex based on the ligand n-phenyledenparaethoxy aniline has been synthesized and its performance as catalyst in single chamber MFCs containing ionic liquids has been compared with a commercial inorganic material such as Raney nickel. The results show that both materials are suitable for bioenergy production and wastewater treatment in the systems. Raney nickel cathodes allow MFCs to reach a maximum power output of 160 mW.m -3 anode , while the iron complex offers lower values. Regarding the wastewater treatment capacity, MFCs working with Raney nickel-based cathodes reach higher values of chemical oxygen demand removal (76%) compared with the performance displayed by the cathodes based on Fe-complex (56%).

Study of physical and sound absorbing property of epoxy blended coir dust biocomposite

NASA Astrophysics Data System (ADS)

Nath, G.; Mishra, S. P.

2016-09-01

Reinforcement biocomposite has gained more attention recently due to its low cost, abundantly availability, low density, specific properties, easy method of separation, enhanced energy recovery, CO2 neutrality, biodegradability and recyclable in nature. As a waste product of coconut fruit, the coconut coir dust (CCD) obtained from the coconut husk. The biocomposite material prepared from the CCD modified with the proper blended solution with the help of ultrasonic technique. The study of adiabatic compressibility of acetone / water (70/30) worth its blending property for bleaching of CCD. The biocomposite material of CCD was prepared with epoxy resin. The different physical properties such as sound absorption coefficient, thermal conductivity and electrical conductivity were measured. The morphological study of biocomposite and measurement of sound absorption coefficient shows good evidence of sound absorbing characteristics of biocomposite of CCD. The sound absorption property of composite material shows a significant result where as the thermal conductivity and electrical conductivity executes a weak result. Thus biocomposite of CCD can acts as a good sound absorber and band conductor of heat and electric current.

Biodegradation of compostable and oxodegradable plastic films by backyard composting and bioaugmentation.

PubMed

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.

Advantages and possibilities of solid recovered fuel cocombustion in the European energy sector.

PubMed

Hilber, Thomas; Maier, Jörg; Scheffknecht, Günter; Agraniotis, Michalis; Grammelis, Panagiotis; Kakaras, Emmanuel; Glorius, Thomas; Becker, Uwe; Derichs, Willy; Schiffer, Hans-Peter; De Jong, Martin; Torri, Lucia

2007-10-01

The 1999/31 Elemental Carbon Directive sets strict rules on the disposal of untreated municipal solid waste in the European Union countries and forces a reduction of the biodegradable quantities disposed off to landfills up to 35% of the amount produced in 1995 in the coming decade. More environmentally friendly waste management options shall be promoted under the framework of the Community Waste Strategy ([96] 399 Final). In this context, the production and thermal use of solid recovered fuels (SRFs), derived from nonhazardous bioresidues and mixed- and mono-waste streams, could be a key element in a future waste management system. Within the scope of the European Demonstration Project, RECOFUEL, SRF cocombustion was demonstrated in two large-scale lignite-fired coal boilers at RWE power station in Weisweiler, Germany. As a consequence of the high biogenic share of the cocombusted material, this approach can be considered beneficial following European Directive 2001/77/EC on electricity from renewable energy sources (directive). During the experimental campaign, the share of SRF in the overall thermal input was adjusted to approximately 2%, resulting into a feeding rate of approximately 25 t/hr. The measurement campaign included boiler measurements in different locations, fuel and ash sampling, and its characterization. The corrosion rates were monitored by dedicated corrosion probes. The overall results showed no significant influence of SRF cocombustion on boiler operation, emissions behavior, and residues quality for the thermal shares applied. Also, no effect of the increased chlorine concentration of the recovered fuel was observed in the flue gas path after the desulfurization unit.

Bio-drying and size sorting of municipal solid waste with high water content for improving energy recovery.

PubMed

Shao, Li-Ming; Ma, Zhong-He; Zhang, Hua; Zhang, Dong-Qing; He, Pin-Jing

2010-07-01

Bio-drying can enhance the sortability and heating value of municipal solid waste (MSW), consequently improving energy recovery. Bio-drying followed by size sorting was adopted for MSW with high water content to improve its combustibility and reduce potential environmental pollution during the follow-up incineration. The effects of bio-drying and waste particle size on heating values, acid gas and heavy metal emission potential were investigated. The results show that, the water content of MSW decreased from 73.0% to 48.3% after bio-drying, whereas its lower heating value (LHV) increased by 157%. The heavy metal concentrations increased by around 60% due to the loss of dry materials mainly resulting from biodegradation of food residues. The bio-dried waste fractions with particle size higher than 45 mm were mainly composed of plastics and papers, and were preferable for the production of refuse derived fuel (RDF) in view of higher LHV as well as lower heavy metal concentration and emission. However, due to the higher chlorine content and HCl emission potential, attention should be paid to acid gas and dioxin pollution control. Although LHVs of the waste fractions with size <45 mm increased by around 2x after bio-drying, they were still below the quality standards for RDF and much higher heavy metal pollution potential was observed. Different incineration strategies could be adopted for different particle size fractions of MSW, regarding to their combustibility and pollution property. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

An advanced pretreatment strategy involving hydrodynamic and acoustic cavitation along with alum coagulation for the mineralization and biodegradability enhancement of tannery waste effluent.

PubMed

Saxena, Shivendu; Rajoriya, Sunil; Saharan, Virendra Kumar; George, Suja

2018-06-01

In the present study, coagulation followed by cavitation was studied as a pretreatment tool for tannery waste effluent (TWE) with the aim of reducing its COD, TOC, TSS etc. and enhancing its biodegradability to make it suitable for anaerobic digestion. Initially, coagulation was applied to TWE using alum as a coagulant. The residual pH of treated effluent was found to be around pH of 4.5 where maximum COD and TSS reduction was achieved. In order to enhance the efficiency of pretreatment process, coagulated tannery waste effluent (CTWE) was further subjected to hydrodynamic cavitation (HC) and ultrasonication (US). In case of HC, effect of process parameters such as inlet pressure and dilution on the treatment of CTWE was initially investigated. Lower operating pressure (5 bar) was more favorable for the treatment of CTWE using HC in order to enhance the biodegradability index (BI) from 0.14 to 0.57 in 120 min. The CTWE samples when subjected to 50% dilution, HC pretreatment exhibited higher percentage and quantum reduction in TOC and COD. On the other hand, pretreatment of TWE using coagulation followed by US demonstrated that BI of effluent was enhanced from 0.10 to 0.41 in 150 min. Energy efficiency evaluation for all processes at their optimized conditions was done based on the actual amount of COD reduced per unit energy delivered to the system. Coagulation followed by HC for the pretreatment of TWE was found to be six times more energy efficient as compared to coagulation followed by US. Copyright © 2018 Elsevier B.V. All rights reserved.

Nanocomposites Based on Biodegradable Polymers

PubMed Central

Armentano, Ilaria; Luzi, Francesca; Morena, Francesco; Martino, Sabata; Torre, Luigi

2018-01-01

In the present review paper, our main results on nanocomposites based on biodegradable polymers (on a time scale from 2010 to 2018) are reported. We mainly focused our attention on commercial biodegradable polymers, which we mixed with different nanofillers and/or additives with the final aim of developing new materials with tunable specific properties. A wide list of nanofillers have been considered according to their shape, properties, and functionalization routes, and the results have been discussed looking at their roles on the basis of different adopted processing routes (solvent-based or melt-mixing processes). Two main application fields of nanocomposite based on biodegradable polymers have been considered: the specific interaction with stem cells in the regenerative medicine applications or as antimicrobial materials and the active role of selected nanofillers in food packaging applications have been critically revised, with the main aim of providing an overview of the authors’ contribution to the state of the art in the field of biodegradable polymeric nanocomposites. PMID:29762482

Process of prototyping coronary stents from biodegradable Fe-Mn alloys.

PubMed

Hermawan, Hendra; Mantovani, Diego

2013-11-01

Biodegradable stents are considered to be a recent innovation, and their feasibility and applicability have been proven in recent years. Research in this area has focused on materials development and biological studies, rather than on how to transform the developed biodegradable materials into the stent itself. Currently available stent technology, the laser cutting-based process, might be adapted to fabricate biodegradable stents. In this work, the fabrication, characterization and testing of biodegradable Fe-Mn stents are described. A standard process for fabricating and testing stainless steel 316L stents was referred to. The influence of process parameters on the physical, metallurgical and mechanical properties of the stents, and the quality of the produced stents, were investigated. It was found that some steps of the standard process such as laser cutting can be directly applied, but changes to parameters are needed for annealing, and alternatives are needed to replace electropolishing. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.