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Sample records for domestic greywater treatment

  1. Quantification and risks associated with bacterial aerosols near domestic greywater-treatment systems.

    PubMed

    Benami, Maya; Busgang, Allison; Gillor, Osnat; Gross, Amit

    2016-08-15

    Greywater (GW) reuse can alleviate water stress by lowering freshwater consumption. However, GW contains pathogens that may compromise public health. During the GW-treatment process, bioaerosols can be produced and may be hazardous to human health if inhaled, ingested, or come in contact with skin. Using air-particle monitoring, BioSampler®, and settle plates we sampled bioaerosols emitted from recirculating vertical flow constructed wetlands (RVFCW) - a domestic GW-treatment system. An array of pathogens and indicators were monitored using settle plates and by culturing the BioSampler® liquid. Further enumeration of viable pathogens in the BioSampler® liquid utilized a newer method combining the benefits of enrichment with molecular detection (MPN-qPCR). Additionally, quantitative microbial risk assessment (QMRA) was applied to assess risks of infection from a representative skin pathogen, Staphylococcus aureus. According to the settle-plate technique, low amounts (0-9.7×10(4)CFUm(-2)h(-1)) of heterotrophic bacteria, Staphylococcus spp., Pseudomonas spp., Klebsiella pneumoniae, Enterococcus spp., and Escherichia coli were found to aerosolize up to 1m away from the GW systems. At the 5m distance amounts of these bacteria were not statistically different (p>0.05) from background concentrations tested over 50m away from the systems. Using the BioSampler®, no bacteria were detected before enrichment of the GW-aerosols. However, after enrichment, using an MPN-qPCR technique, viable indicators and pathogens were occasionally detected. Consequently, the QMRA results were below the critical disability-adjusted life year (DALY) safety limits, a measure of overall disease burden, for S. aureus under the tested exposure scenarios. Our study suggests that health risks from aerosolizing pathogens near RVFCW GW-treatment systems are likely low. This study also emphasizes the growing need for standardization of bioaerosol-evaluation techniques to provide more accurate

  2. A review of greywater characteristics and treatment processes.

    PubMed

    Boyjoo, Yash; Pareek, Vishnu K; Ang, Ming

    2013-01-01

    This paper presents a comprehensive literature review of different characteristics of greywater (GW) and current treatment methods. GW is domestic wastewater excluding toilet waste and can be classified as either low-load GW (excluding kitchen and laundry GW) or high-load GW (including kitchen and/or laundry). This review provides information on the quantity of GW produced, its constituents (macro and micro), existing guidelines for wastewater reuse, current treatment methods (from storage to disinfection) as well as related costs and environmental impacts. Moreover some successful examples from various countries around the world are examined. The current preferred treatments for GW use physical and biological/natural systems. Recently, chemical systems like coagulation, adsorption and advanced oxidation processes (AOPs) have been considered and have been successful for low to moderate strength GW. The presence of xenobiotic organic compounds (XOC), which are hazardous micropollutants in GW, is emphasised. Since conventional treatments are not efficient at removing XOC, it is recommended that future studies look at chemical treatment, especially AOPs that have been found to be successful at mineralising recalcitrant organic compounds in wastewater. PMID:23552228

  3. Characteristics and treatment of greywater--a review.

    PubMed

    Ghaitidak, Dilip M; Yadav, Kunwar D

    2013-05-01

    Safe and sufficient quantity of water is necessary for a healthy growth of human beings. The gap between water demand and available water supply is increasing day by day. Proper sanitation, especially decentralized approach, can solve the problem of water supply and wastewater management and that can be done by reuse of greywater. Typically, from a household, greywater (GW) flow is around 65 % of the total wastewater flow. Further light greywater is around 50 % of the total GW. Hence, GW has a high potential for recycle and reuse. The aim of this article is to reveal the present state of art in GW treatment and to identify the further scope for research. Present article contains a review on per capita GW generation, GW characteristics, and its treatment. Around 22 treatment systems comprising different treatment processes are discussed in detail for removal efficiency of pollutants, effluent concentrations and their compliance with wastewater reuse guidelines and standards. Constructed wetland and filtration were found efficient in the removal of most of the reuse parameters compared to other technologies. Anaerobic followed by aerobic system with post-disinfection unit may be a sustainable option for GW treatment for reuse. There is a need to develop the technologies for GW treatment at household level to increase the reuse practises at grass root level. Further, there is need of development of flow diagram with different technologies by targeting the type of reuse (flushing, gardening, agriculture, etc.). PMID:23397178

  4. Legionella pneumophila: From potable water to treated greywater; quantification and removal during treatment.

    PubMed

    Blanky, Marina; Rodríguez-Martínez, Sara; Halpern, Malka; Friedler, Eran

    2015-11-15

    Greywater is an alternative water source that can help alleviate stress on depleted water resources. The main options for greywater reuse are toilet flushing and garden irrigation, both producing aerosols. For that reason transmission of inhalable pathogens like Legionella present a potential risk. To improve the understanding about Legionella in greywater, we traced the pathogen seasonally from the potable water system to the final steps of the greywater treatment in four houses in northern Israel. Physicochemical and microbiological parameters were analyzed in order to assess background greywater quality and to establish possible associations with Legionella. The mean concentrations of Legionella pneumophila isolated from the potable water system were 6.4×10(2) and 5.9×10(3) cfu/l in cold and hot water respectively. By amending the ISO protocol for Legionella isolation from drinking water, we succeeded in quantifying Legionella in greywater. The mean Legionella concentrations that were found in raw, treated and treated chlorinated greywater were 1.2×10(5), 2.4×10(4) and 5.7×10(3) cfu/l respectively. While Legionella counts in potable water presented a seasonal pattern with high concentrations in summer, its counts in greywater presented an almost inversed pattern. Greywater treatment resulted in 95% decrease in Legionella counts. No significant difference was found between Legionella concentrations in potable water and the treated chlorinated greywater. These findings indicate that regarding Legionella, reusing treated chlorinated greywater would exhibit a risk that is very similar to the risk associated with using potable water for the same non-potable uses. PMID:26188406

  5. Contribution of N-Nitrosamines and Their Precursors to Domestic Sewage by Greywaters and Blackwaters.

    PubMed

    Zeng, Teng; Mitch, William A

    2015-11-17

    N-nitrosamines and their precursors are significant concerns for water utilities exploiting wastewater-impacted water supplies, particularly those practicing potable reuse of wastewater. Previous efforts to identify specific precursors in municipal wastewater accounting for N-nitrosamine formation have met with limited success. As an alternative, we quantified the relative importance of greywater (i.e., shower, kitchen sink, bathroom washbasin, and laundry) and blackwater (i.e., urine and feces) streams in terms of their loadings of ambient specific and total N-nitrosamines and chloramine-reactive and ozone-reactive N-nitrosamine precursors to domestic sewage. Accounting for the volume fractions of individual greywater and blackwater streams, laundry water represented the most significant source of N-nitrosamines and their precursors, followed by shower water and urine. Laundry water was particularly important for ozone-reactive N-nitrosamine precursors, accounting for ∼99% of N-nitrosodimethylamine (NDMA) precursors and ∼69% of precursors for other uncharacterized N-nitrosamines. For the other greywater streams, consumer products contributed additional N-nitrosamines and precursors, but the remarkable uniformity across different products suggested the importance of common macroconstituents. The consumption of a standard dose of the antacid ranitidine substantially increased NDMA and its chloramine-reactive precursors in urine. Nevertheless, nearly 40% of the American population would need to consume ranitidine daily to match the NDMA loadings from laundry water. PMID:26496512

  6. Use of domestic greywater for small-scale irrigation of food crops: Effects on plants and soil

    NASA Astrophysics Data System (ADS)

    Rodda, N.; Salukazana, L.; Jackson, S. A. F.; Smith, M. T.

    Disposal of greywater presents a problem in areas served with on-site sanitation or in areas with poor service provision. Such areas often also face challenges with respect to food security. Use of greywater for irrigation of food crops represents a possible beneficial use of greywater which can contribute to household food supply and to informal income generation. In this study, an above-ground crop (Swiss chard, Betavulgaris var. cicla) and a below-ground crop (carrot, Daucus carota) were irrigated in pots with mixed greywater sourced from households in an informal settlement. A simple form of sub-surface irrigation was used. Plant growth, crop yield, and levels of macro- and micronutrients in crops and soil were monitored through six growth cycles. Equivalent treatments, irrigated with either tap water or a hydroponic nutrient solution, were conducted for comparison. The same soil was used throughout to allow accumulation of greywater-derived substances in soil to be detected. The results indicated that: (i) irrigation with greywater increased plant growth and yield relative to crops irrigated with tap water only, although crops irrigated with hydroponic nutrient solution yielded the highest growth and yield; (ii) irrigation with greywater improved plant nutrient content relative to crops irrigated with tap water; (iii) soil irrigated with greywater showed increased electrical conductivity and increased concentrations of metals over time, coupled with an increase in sodium and metal concentrations in crops. Thus, provided precautions are taken with regard to salt and metal accumulation, greywater offers a potential source of water for household crop irrigation which additionally shows some fertiliser properties.

  7. Quantitative and qualitative greywater characterization in Greek households and investigation of their treatment using physicochemical methods.

    PubMed

    Antonopoulou, Georgia; Kirkou, Amalia; Stasinakis, Athanasios S

    2013-06-01

    Data for the quantity of greywater produced in Greek households was collected from two different cities, while samples from different residences were taken for greywater's quality characterization. Laboratory experiments were also performed to investigate the use of coagulation on COD and TSS removal from two different types of greywater, while a combined treatment consisting of coagulation, sand filtration and adsorption on granular activated carbon (GAC) was applied to achieve adequate quality for greywater reuse. According to the results, average greywater production in Greek residences was 82.6 ± 49.3 L per inhabitant and day, while the major sources were shower/bathtub and laundry, contributing to 41% and 26%, respectively. On the other hand, blackwater production was estimated at 59.4 ± 29.6L per inhabitant and day. Greywater produced in shower/bathtub and hand basin had similar quality characteristics, while kitchen sink's greywater were more contaminated, presenting lower pH values and higher concentrations of TSS and total COD. Coagulation experiments with FeCl3 and Al2(SO4)3 showed that process efficiency was differentiated significantly according to the type of greywater and the coagulant used. The highest removal efficiency (COD: 81%; TSS: 79%) was achieved for greywater that did not contain wastewater from the laundry and for Al2(SO4)3×14 H2O dosage of 800 mg L(-1). The application of coagulation, sand filtration and GAC adsorption resulted to average concentrations of COD and TSS equal to 28 ± 11 and 11 ± 3 mg L(-1), respectively, in treated greywater. PMID:23563256

  8. Designing slanted soil system for greywater treatment for irrigation purposes in rural area of arid regions.

    PubMed

    Maiga, Y; Moyenga, D; Nikiema, B C; Ushijima, K; Maiga, A H; Funamizu, N

    2014-01-01

    To solve the unpleasant disposal of greywater in rural area and allow its collection for reuse in gardening, a slanted soil treatment system (SSTS) was designed and installed in two households. Granitic gravel of 1-9 mm size was used as the filter medium. The aim of this study was to design a SSTS and assess its suitability as a treatment system allowing greywater reuse in gardening. The efficiency of the SSTS was assessed based on organic matter and bacterial pollution removal. The developed SSTS allowed the collection of greywater from three main sources (shower, dishwashing and laundry) in rural area. The SSTS is efficient in removing at least 50% of suspended solids, chemical oxygen demand and biological oxygen demand. The study highlighted that, contrary to the common perception, greywater streams in rural area are heavily polluted with faecal indicators. The removal efficiency of faecal indicators was lower than 2 log units, and the bacteriological quality of the effluents is generally higher than the WHO reuse guidelines for restricted irrigation. Longer retention time is required to increase the efficiency. The possibility of reusing the treated greywater as irrigation water is discussed on the basis of various qualitative parameters. The SSTS is a promising greywater treatment system for small communities in the rural area in the Sahelian region. To increase the treatment efficiency, future research will focus on the characteristics of the SSTS, the grain size and the establishment of a pretreatment step. PMID:25189850

  9. Presence of selected priority and personal care substances in an onsite bathroom greywater treatment facility.

    PubMed

    Eriksson, E; Donner, E; Ledin, A

    2010-01-01

    In recent years, concerns about climate change and the inefficient use and ongoing pollution of water resources have increased the political motivation to encourage water recycling. This has led to the widespread introduction of water saving measures and to advances in the decentralised treatment and reuse of wastewater. In particular, the treatment and reuse of greywater has received attention, although important information such as greywater substance loadings is still only rarely available. With the implementation of the European Water Framework Directive the focus on controlling and phasing-out Priority/Priority Hazardous Substances (PS/PHS) is growing, and it is vital to know their sources and flows in order to generate sustainable emission control strategies. The main objective of this study was to quantify the concentrations and loads of PS/PHS and personal care substances in bathroom greywater, and to thereby assess the contribution of household activities to municipal wastewater loads for these substances. Nickel and mercury may be sourced substantially from household activities as it shown in the paper that bathroom greywater contributed a significant proportion of the overall load of these substances at the municipal wastewater treatment plant. Organic matter in the influent greywater was found to be principally associated with large particles (>8 µm), however it was the dissolved and small sized particles that were predominantly removed in the treatment. PMID:21123919

  10. On-site greywater treatment and reuse in multi-storey buildings.

    PubMed

    Friedler, E; Kovalio, R; Galil, N I

    2005-01-01

    The paper presents a study of a pilot plant treating light greywater for seven flats. The pilot plant combines biological treatment (RBC) with physicochemical treatment (sand filtration and disinfection). The pilot plant produced effluent of excellent quality, meeting the urban reuse quality regulations, and was very efficient in TSS turbidity and BOD removal: 82%, 98% and 96%, respectively. COD removal was somewhat lower (70-75%) indicating that the greywater may contain slowly-biodegradable organics. The RBC (attached growth biological system) was able to retain most of the solids as a result of bioflocculation; further it was proven to have very stable and reliable performance. Faecal coliforms and heterotrophic reductions were very high (100% and 99.99%, respectively) producing effluent that also met drinking water standards. The combination of low organic matter, nutrients and microbial indicators reduces the regrowth and fouling potentials in the reuse system, thus ensuring safe reuse of the treated greywater for toilet flushing. PMID:16104421

  11. Bathroom greywater recycling using polyelectrolyte-complex bilayer membrane: Advanced study of membrane structure and treatment efficiency.

    PubMed

    Oh, K S; Poh, P E; Chong, M N; Chan, E S; Lau, E V; Saint, C P

    2016-09-01

    Polyelectrolyte-complex bilayer membrane (PCBM) was fabricated using biodegradable chitosan and alginate polymers for subsequent application in the treatment of bathroom greywater. In this study, the properties of PCBMs were studied and it was found that the formation of polyelectrolyte network reduced the molecular weight cut-off (MWCO) from 242kDa in chitosan membrane to 2.71kDa in PCBM. The decrease in MWCO of PCBM results in better greywater treatment efficiency, subsequently demonstrated in a greywater filtration study where treated greywater effluent met the household reclaimed water standard of <2 NTU turbidity and <30ppm total suspended solids (TSS). In addition, a further 20% improvement in chemical oxygen demand (COD) removal was achieved as compared to a single layer chitosan membrane. Results from this study show that the biodegradable PCBM is a potential membrane material in producing clean treated greywater for non-potable applications. PMID:27185127

  12. Quantification and characterization of greywater from schools.

    PubMed

    Alsulaili, Abdalrahman D; Hamoda, Mohamed F

    2015-01-01

    Survey of schools of different education levels (primary, intermediate and secondary) in Kuwait showed an average greywater generation rate of 7.3 L/p/d and varied in the range of 2.9-16 l/p/d, reflecting the school level of education (i.e. student age). The highest rates were observed for primary schools while the lowest rates were observed in secondary schools where students are more mature and use the water more wisely. The greywater characteristics indicated waste with low chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5) values but relatively high solids, conductivity, and sodium content due to excessive use of hand soap. Total coliform values ranged between 89 and 352 most probable number (MPN)/mL with an average of 196 MPN/mL while no fecal coliform values were detected. Greywater collected from schools is classified as light greywater and contains much lower levels of organic matter and nutrients compared to residential greywater and domestic wastewater. It is suitable for non-potable reuse after minimal treatment since microbial contamination may pose a serious threat to health if greywater comes into contact with humans. It also provides a good opportunity for reuse in toilet flushing since it can be easily collected from wash sinks and fountains, as major sources, and recycled. PMID:26606091

  13. Laundry greywater treatment using a fluidized bed reactor: a proposed model based on greywater biodegradation and residence time distribution approach.

    PubMed

    David, Pierre-luc; Bulteau, Gaëlle; Humeau, Philippe; Gérente, Claire; Andrès, Yves

    2013-01-01

    The increasing demand for water and the decrease in global water resources require research into alternative solutions to preserve them. The present study deals with the optimization of a treatment process, i.e. an aerobic fluidized bed reactor and the modelling of the degradation that takes place within it. The methodology employed is based on the hydrodynamics of the treatment process linked to the biodegradation kinetics of greywater coming from a washing machine. The residence time distribution (RTD) approach is selected for the hydrodynamic study. Biodegradation kinetics are quantified by respirometry and dissolved organic carbon (DOC) analysis on several mass quantities of colonized particles. RTD determinations show that there are no dysfunctions in the fluidized bed. Its hydrodynamic behaviour is similar to the one of a continuous stirred-tank reactor. A first-order reaction is obtained from the DOC biodegradation study. A model describing the degradation that takes place into the reactor is proposed, and from a sensitive study, the influence of the operating conditions on DOC biodegradation is defined. The theoretical results calculated from the first-order equation C(t) = 0.593 x C(0) x e(-kt) are compared with the experimental results and validated by a Student test. The value of the kinetic constant k is 0.011 h(-1) in the presence of a biomass carrier. The results highlight that it is possible to design a reactor in order to obtain a carbon content lower than 15 mg C L(-1) when the characteristics of raw greywater are known. PMID:24617067

  14. Application of a low cost ceramic filter to a membrane bioreactor for greywater treatment.

    PubMed

    Hasan, Md Mahmudul; Shafiquzzaman, Md; Nakajima, Jun; Ahmed, Abdel Kader T; Azam, Mohammad Shafiul

    2015-03-01

    The performance of a low cost and simple ceramic filter to a membrane bioreactor (MBR) process was evaluated for greywater treatment. The ceramic filter was submerged in an acrylic cylindrical column bioreactor. Synthetic greywater (prepared by shampoo, dish cleaner and laundry detergent) was fed continuously into the reactor. The filter effluent was obtained by gravitational pressure. The average flux performance was observed to be 11.5 LMH with an average hydraulic retention time of 1.7 days. Complete biodegradation of surfactant (methylene blue active substance removal: 99-100%) as well as high organic removal performance (biochemical oxygen demand: 97-100% and total organic carbon: >88%) was obtained. The consistency of flux (11.5 LMH) indicated that the filter can be operated for a long time without fouling. The application of this simple ceramic filter would make MBR technology cost-effective in developing countries for greywater reclamation and reuse. PMID:25842534

  15. Socio-economic and psychological predictors of domestic greywater and rainwater collection: Evidence from Australia

    NASA Astrophysics Data System (ADS)

    Ryan, Anthony M.; Spash, Clive L.; Measham, Thomas G.

    2009-12-01

    SummaryThe importance of securing water supply necessitates that all options be explored. Research has indicated that demand on water catchments can be substantially decreased when a large proportion of households reuse greywater and/or install rainwater tanks. This paper reports on an internet survey completed by 354 households residing in the Australian Capital Territory and surrounding regions. Statistical analyses examined the relationship between socio-economic and psychological variables and the likelihood of the garden being irrigated with greywater and/or rainwater. The results show income, gender, age and education could not differentiate residents who were irrigating their garden with water from a tank from residents who were not. Residents who used tank water on their gardens had a higher self-reported understanding of a range of water supply options. Female participants and lower income residents were more likely to use greywater on their garden. Participants who irrigated the garden with greywater were more likely to judge various other water collection and recycling proposals as being appropriate. General concerns about water collection and reuse risks were not found to predict which households used tank water and/or greywater on their garden.

  16. Resources and nutrients oriented greywater treatment for non-potable reuses.

    PubMed

    Li, Fangyue; Behrendt, Joachim; Wichmann, Knut; Otterpohl, Ralf

    2008-01-01

    This paper evaluated the performance and suitability of a resources and nutrients oriented decentralized greywater treatment system which uses a submerged spiral wound module. This greywater treatment system is aimed at treating and recovering the resources present in the wastewater. The study revealed that the UF membrane filtration system was able to maintain a permeate flux between 6 and 10 L/m2/h. TOC can be reduced from the influent value of 161 to 28.6 mg/L in the permeate, meaning an average elimination rate of 83.4%. In addition, soluble nutrients such as ammonia and phosphorus can pass through the UF membrane and remain in the permeate. The total nitrogen and total phosphorus in the permeate were 16.7 and 6.7 mg/L respectively. The permeate was low in turbidity (below 1 NTU) and free of suspended solids and E. coli and had an excellent physical appearance. The permeate can be used in gardening and agriculture for irrigation and soil fertilization or alternatively for toilet flushing after disinfection. The retentate generated in this system can be treated with blackwater and kitchen waste in an anaerobic digester at a later stage for producing biogas or compost. PMID:18587176

  17. Simplified greywater treatment systems: Slow filters of sand and slate waste followed by granular activated carbon.

    PubMed

    Zipf, Mariah Siebert; Pinheiro, Ivone Gohr; Conegero, Mariana Garcia

    2016-07-01

    One of the main actions of sustainability that is applicable to residential, commercial, and public buildings is the rational use of water that contemplates the reuse of greywater as one of the main options for reducing the consumption of drinking water. Therefore, this research aimed to study the efficiencies of simplified treatments for greywater reuse using slow sand and slow slate waste filtration, both followed by granular activated carbon filters. The system monitoring was conducted over 28 weeks, using analyses of the following parameters: pH, turbidity, apparent color, biochemical oxygen demand (BOD), chemical oxygen demand (COD), surfactants, total coliforms, and thermotolerant coliforms. The system was run at two different filtration rates: 6 and 2 m(3)/m(2)/day. Statistical analyses showed no significant differences in the majority of the results when filtration rate changed from 6 to 2 m(3)/m(2)/day. The average removal efficiencies with regard to the turbidity, apparent color, COD and BOD were 61, 54, 56, and 56%, respectively, for the sand filter, and 66, 61, 60, and 51%, respectively, for the slate waste filter. Both systems showed good efficiencies in removing surfactants, around 70%, while the pH reached values of around 7.80. The average removal efficiencies of the total and thermotolerant coliforms were of 61 and 90%, respectively, for the sand filter, and 67 and 80%, respectively, for the slate waste filter. The statistical analysis found no significant differences between the responses of the two systems, which attest to the fact that the slate waste can be a substitute for sand. The maximum levels of efficiency were high, indicating the potential of the systems, and suggesting their optimization in order to achieve much higher average efficiencies. PMID:27045540

  18. Reliability of on-site greywater treatment systems in Mediterranean and arid environments - a case study.

    PubMed

    Alfiya, Y; Gross, A; Sklarz, M; Friedler, E

    2013-01-01

    On-site greywater (GW) treatment and reuse is gaining popularity. However, a main point of concern is that inadequate treatment of such water may lead to negative environmental and health effects. Maintenance of single-family home GW systems is usually performed by home owners with limited professional support. Therefore, unless GW systems are reliable, environmental and public health might be compromised. This study is aimed at investigating the reliability of on-site recirculated vertical flow constructed wetlands (RVFCW) in 20 single-family homes. In order to ensure reliability, the failure-tree approach was adopted during the design and construction of the systems. The performance of the systems was monitored for 1.5 years, by evaluating treated GW flow and quality, and by recording all malfunctions and maintenance work. Only 39 failures occurred during this period, of which four caused irrigation with impaired quality GW, while the rest led to no irrigation. The mean time between failures (MTBF) was 305 days; two out of the 20 systems suffered from seven malfunctions (each), while nine systems did not fail at all. Thus, it can be postulated that if on-site GW treatment systems are designed with the right controls, and if scheduled (basic and relatively infrequent) maintenance is performed, GW reuse can be safe to the environment and human health. PMID:23508166

  19. Simulation and verification of hydraulic properties and organic matter degradation in sand filters for greywater treatment.

    PubMed

    Karlsson, Susanna Ciuk; Langergraber, G; Pell, M; Dalahmeh, S; Vinnerås, B; Jönsson, H

    2015-01-01

    To evaluate the treatment performance of vertical flow sand filters, the HYDRUS wetland module was used to simulate treatment in an experimental set-up. The laboratory filters were intermittently dosed with artificial greywater at a hydraulic loading rate of 0.032 m³ m⁻² day⁻¹ and an organic loading rate of 0.014 kg BOD5 m⁻² day⁻¹. The hydraulic properties of the filter were characterised, as were inflow and outflow concentrations of chemical oxygen demand (COD), biochemical oxygen demand (BOD), ammonia, nitrate and total nitrogen. The inverse simulation function of the HYDRUS software was used to calibrate the water flow model. The observed effect of water flowing faster along the column wall was included in the inverse simulations. The biokinetic model was calibrated by fitting heterotrophic biomass growth to measurements of potential respiration rate. Emphasis was put on simulating outflow concentrations of organic pollutants. The simulations were conducted using three models of varying degree of calibration effort and output accuracy. The effluent concentration was 245 mg COD L⁻¹ for the laboratory filters, 134 mg COD mg L⁻¹ for the model excluding wall flow effects and 338 mg COD mg L⁻¹ for the model including wall flow effects. PMID:25714643

  20. Greywater reuse: A strategy for water demand management in Harare?

    NASA Astrophysics Data System (ADS)

    Madungwe, Emaculate; Sakuringwa, Saniso

    Greywater is wastewater from baths, sinks and washing machines, accounting for about 60% of the outflow from homes. It contains little pathogens and 90% less nitrogen than toilet water, so does not require the same treatment process. With the increasing demand for freshwater, its use may reduce irrigation water needs, increasing its availability of freshwater for other primary uses. Agriculture is the main water consumer in Africa, which cannot be compromised due to its role in domestic food security and export supplies. The purpose of this paper is to demonstrate findings of the research done on benefits of greywater reuse in some countries, applicable to African countries. In Australia, greywater reuse has reduced freshwater demand, strain on wastewater treatment plants and energy consumption. Aquifer recharge has improved due to increased infiltration flows from greywater uses. In Lebanon, greywater is a valuable resource for encouraging plant growth from nutrients that may otherwise have been wasted. Palestine shares similar climate and water scarcity conditions with most arid sub-Saharan African countries, yet utilizes grey water in production of crops and citrus fruits. Thus use of grey water should be possible in African cities such as Harare, where nearly two thirds of the population rely on agriculture for livelihoods. The problem of blue green algae in sewerage ponds and water reservoirs is significantly reduced by household reuse of grey water in Mexico. Water savings are increased and expenses reduced, as illustrated by the reduction in consumption of municipality freshwater supplies in South African urban areas. Rural communities and schools in Namibia and Egypt have raised funds from grey water reuse in banana plantations. A possible constraint to this strategy could be the unavailability of appropriate technology for primary treatment of grey water before reuse. This strategy may pose health risks where water quality tests are unknown or unavailable

  1. Chemical simulation of greywater.

    PubMed

    Abed, Suhail Najem; Scholz, Miklas

    2016-01-01

    Sustainable water resources management attracts considerable attention in today's world. Recycling and reuse of both wastewater and greywater are becoming more attractive. The strategy is to protect ecosystem services by balancing the withdrawal of water and the disposal of wastewater. In the present study, a timely and novel synthetic greywater composition has been proposed with respect to the composition of heavy metals, nutrients and organic matter. The change in water quality of the synthetic greywater due to increasing storage time was monitored to evaluate the stability of the proposed chemical formula. The new greywater is prepared artificially using analytical-grade chemicals to simulate either low (LC) or high (HC) pollutant concentrations. The characteristics of the synthetic greywater were tested (just before starting the experiment, after two days and a week of storage under real weather conditions) and compared to those reported for real greywater. Test results for both synthetic greywater types showed great similarities with the physiochemical properties of published findings concerning real greywater. Furthermore, the synthetic greywater is relatively stable in terms of its characteristics for different storage periods. However, there was a significant (p < .05) reduction in 5-day biochemical oxygen demand (BOD5) for both low (LC) and high (HC) concentrations of greywater after two days of storage with reductions of 62% and 55%, respectively. A significant (p < .05) change was also noted for the reduction (70%) of nitrate-nitrogen (NO3-N) concerning HC greywater after seven days of storage. PMID:26745659

  2. Legionella spp. isolation and quantification from greywater

    PubMed Central

    Rodríguez-Martínez, Sara; Blanky, Marina; Friedler, Eran; Halpern, Malka

    2015-01-01

    Legionella, an opportunistic human pathogen whose natural environment is water, is transmitted to humans through inhalation of contaminated aerosols. Legionella has been isolated from a high diversity of water types. Due its importance as a pathogen, two ISO protocols have been developed for its monitoring. However, these two protocols are not suitable for analyzing Legionella in greywater (GW). GW is domestic wastewater excluding the inputs from toilets and kitchen. It can serve as an alternative water source, mainly for toilet flushing and garden irrigation; both producing aerosols that can cause a risk for Legionella infection. Hence, before reuse, GW has to be treated and its quality needs to be monitored. The difficulty of Legionella isolation from GW strives in the very high load of contaminant bacteria. Here we describe a modification of the ISO protocol 11731:1998 that enables the isolation and quantification of Legionella from GW samples. The following modifications were made:•To enable isolation of Legionella from greywater, a pre-filtration step that removes coarse matter is recommended.•Legionella can be isolated after a combined acid-thermic treatment that eliminates the high load of contaminant bacteria in the sample. PMID:26740925

  3. Legionella spp. isolation and quantification from greywater.

    PubMed

    Rodríguez-Martínez, Sara; Blanky, Marina; Friedler, Eran; Halpern, Malka

    2015-01-01

    Legionella, an opportunistic human pathogen whose natural environment is water, is transmitted to humans through inhalation of contaminated aerosols. Legionella has been isolated from a high diversity of water types. Due its importance as a pathogen, two ISO protocols have been developed for its monitoring. However, these two protocols are not suitable for analyzing Legionella in greywater (GW). GW is domestic wastewater excluding the inputs from toilets and kitchen. It can serve as an alternative water source, mainly for toilet flushing and garden irrigation; both producing aerosols that can cause a risk for Legionella infection. Hence, before reuse, GW has to be treated and its quality needs to be monitored. The difficulty of Legionella isolation from GW strives in the very high load of contaminant bacteria. Here we describe a modification of the ISO protocol 11731:1998 that enables the isolation and quantification of Legionella from GW samples. The following modifications were made:•To enable isolation of Legionella from greywater, a pre-filtration step that removes coarse matter is recommended.•Legionella can be isolated after a combined acid-thermic treatment that eliminates the high load of contaminant bacteria in the sample. PMID:26740925

  4. Effects of long-term greywater disposal on soil: A case study.

    PubMed

    Siggins, Alma; Burton, Vanessa; Ross, Craig; Lowe, Hamish; Horswell, Jacqui

    2016-07-01

    This study investigated the environmental health risks to soil and potential risks to groundwater associated with long term (8-18years) greywater disposal practices. Land application of greywater is likely to have environmental impacts, which may be positive or negative. Greywater can contain plant macronutrients that may benefit plant growth. Conversely, high levels of surfactants, oils, grease, sodium and potentially pathogenic organisms may negatively impact environmental and human health. In this study, land disposal of untreated greywater was practiced at five coastal domestic properties. At each property, soil samples were collected at two depths from areas used for greywater disposal and from control areas that were not exposed to greywater. Soils were analysed for chemical and biological responses to greywater exposure. Generally, greywater irrigated soils had higher pH, Olsen P, base saturation, and increased soil microbial activity (as measured by biomass carbon, basal respiration and dehydrogenase activity). A pH of >9 was recorded for some greywater treated soil samples. Escherichia coli (E. coli) were detected at up to 10(3)MPN/g in the greywater exposed surface soils at some sites. Terminal Restriction Fragment Length Polymorphism (TRFLP) analysis revealed that greywater affected the soil microbial community structure, which may have implications for soil health and fertility. Overall, this study shows that the long-term application of greywater at the investigated sites had a moderate impact on the soil environment. This may have been due to the sandy soils and high rainfall that would flush the soil. Increases in microbial biomass and dehydrogenase indicate that greywater application may be beneficial for plant growth. However, high levels of E. coli in some soils may be a risk to human health and sub-surface irrigation should be the recommended application method. PMID:27037884

  5. Reduction of microbial risk associated with greywater by disinfection processes for irrigation.

    PubMed

    Al-Gheethi, A A; Mohamed, R M S Radin; Efaq, A N; Amir Hashim, M K

    2016-06-01

    Greywater is one of the most important alternative sources for irrigation in arid and semi-arid countries. However, the health risk associated with the microbial contents of these waters limits their utilization. Many techniques have been developed and used to generate a high microbiological quality of greywater. The main problem in the treatment of greywater lies in the nature of pathogenic bacteria in terms of their ability to survive during/after the treatment process. The present review focused on the health risk associated with the presence of pathogenic bacteria in greywater and the treatment technologies used for the disinfection processes. PMID:27280605

  6. Potential fresh water saving using greywater in toilet flushing in Syria.

    PubMed

    Mourad, Khaldoon A; Berndtsson, Justyna C; Berndtsson, Ronny

    2011-10-01

    Greywater reuse is becoming an increasingly important factor for potable water saving in many countries. Syria is one of the most water scarce countries in the Middle East. However, greywater reuse is still not common in the country. Regulations and standards for greywater reuse are not available. Recently, however, several stakeholders have started to plan for greywater reuse. The main objective of this paper is to evaluate the potential for potable water saving by using greywater for toilet flushing in a typical Syrian city. The Sweida city in the southern part of Syria was chosen for this purpose. Interviews were made in order to reflect the social acceptance, water consumption, and the percentage of different indoor water uses. An artificial wetland (AW) and a commercial bio filter (CBF) were proposed to treat the greywater, and an economic analysis was performed for the treatment system. Results show that using treated greywater for toilet flushing would save about 35% of the drinking water. The economic analyses of the two proposed systems showed that, in the current water tariff, the payback period for AW and CBF in block systems is 7 and 52 years, respectively. However, this period will reduce to 3 and 21 years, respectively, if full water costs are paid by beneficiaries. Hence, introducing artificial wetlands in order to make greywater use efficient appears to be a viable alternative to save potable water. PMID:21621904

  7. Environmental impact and health risks associated with greywater irrigation: a case study.

    PubMed

    Gross, A; Azulai, N; Oron, G; Ronen, Z; Arnold, M; Nejidat, A

    2005-01-01

    There is an increasing trend to use greywater for irrigation in households. This is partly due to the notion that greywater is of better quality than wastewater and therefore does not need extensive treatment beyond addressing public health issues. The aim of the study was to evaluate the environmental impact and health risks associated with the use of greywater for irrigation on a small private farm. Over a three-year period, each of three plots on a farm was irrigated with either freshwater, fertilized water, or greywater. Irrigation water and soil from the plots were analyzed for a wide range of chemical and microbial variables. Results suggest that greywater may be of similar quality to wastewater in several parameters such as BOD and faecal coliforms. For some other variables such as boron and surfactants, greywater may even be of worse quality than wastewater. Long-term irrigation of arid loess soil with greywater may result in accumulation of salts, surfactants and boron in the soil, causing changes in soil properties and toxicity to plants. Faecal coliforms did not survive in the soil. Treating greywater before using it for irrigation is recommended, even in places where this is not a requirement. PMID:16312963

  8. Safe on-site reuse of greywater for irrigation - a critical review of current guidelines.

    PubMed

    Maimon, Adi; Tal, Alon; Friedler, Eran; Gross, Amit

    2010-05-01

    Reuse of greywater for landscape irrigation can significantly reduce domestic water consumption. Alongside its benefits, there are potential drawbacks to greywater reuse, raising legitimate concerns about the impact on human and environmental health. In this review, a risk assessment framework is used to assess the adequacy of different regulations to ensure safe and long-lasting, onsite greywater reuse for irrigation. Existing regulations from around the world are assessed along with a standardized evaluation of measures taken to protect public and environmental health. In most cases, human health considerations currently dominate regulatory strategies, while environmental risks are either ignored or underrepresented. A distinction between single and multiple households was found to be a fundamental component of the regulations which often lead to approved utilization of untreated greywater among single households. We concluded that the use of untreated greywater is not recommended, especially in multihousehold systems as it may compromise public health, with single household systems posing more likely risks to the environment. Existing rules to control greywater use should be further revised toward the establishment of a more advanced regulatory system which can avert the salient potential risks associated with greywater reuse, while exploiting the enormous potential of this alternative water resource. PMID:20380412

  9. Floating treatment wetlands for domestic wastewater treatment.

    PubMed

    Faulwetter, J L; Burr, M D; Cunningham, A B; Stewart, F M; Camper, A K; Stein, O R

    2011-01-01

    Floating islands are a form of treatment wetland characterized by a mat of synthetic matrix at the water surface into which macrophytes can be planted and through which water passes. We evaluated two matrix materials for treating domestic wastewater, recycled plastic and recycled carpet fibers, for chemical oxygen demand (COD) and nitrogen removal. These materials were compared to pea gravel or open water (control). Experiments were conducted in laboratory scale columns fed with synthetic wastewater containing COD, organic and inorganic nitrogen, and mineral salts. Columns were unplanted, naturally inoculated, and operated in batch mode with continuous recirculation and aeration. COD was efficiently removed in all systems examined (>90% removal). Ammonia was efficiently removed by nitrification. Removal of total dissolved N was ∼50% by day 28, by which time most remaining nitrogen was present as NO(3)-N. Complete removal of NO(3)-N by denitrification was accomplished by dosing columns with molasses. Microbial communities of interest were visualized with denaturing gradient gel electrophoresis (DGGE) by targeting specific functional genes. Shifts in the denitrifying community were observed post-molasses addition, when nitrate levels decreased. The conditioning time for reliable nitrification was determined to be approximately three months. These results suggest that floating treatment wetlands are a viable alternative for domestic wastewater treatment. PMID:22105133

  10. Potential of organic filter materials for treating greywater to achieve irrigation quality: a review.

    PubMed

    Dalahmeh, Sahar S; Hylander, Lars D; Vinnerås, Björn; Pell, Mikael; Oborn, Ingrid; Jönsson, Håkan

    2011-01-01

    The objectives of this literature review were to: (i) evaluate the impact of greywater generated in rural communities, with the emphasis on Jordanian conditions, on soil, plant and public health and assess the need for treatment of this greywater before it is used for irrigation, and (ii) assess the potential of different types of organic by-products as carrier material in different filter units for removal of pollutants from greywater. Greywater with high BOD5, COD, high concentrations of SS, fat, oil and grease and high levels of surfactants is commonly found in rural areas in Jordan. Oxygen depletion, odour emission, hydrophobic soil phenomena, plant toxicity, blockage of piping systems and microbiological health risks are common problems associated with greywater without previous treatment. Organic by-products such as wood chips, bark, peat, wheat straw and corncob may be used as carrier material in so-called mulch filters for treating wastewater and greywater from different sources. A down-flow-mode vertical filter is a common setup used in mulch filters. Wastewaters with a wide range of SS, cBOD5 and COD fed into different mulch filters have been studied. The different mulch materials achieved SS removal ranging between 51 and 91%, a BOD5 reduction range of 55-99.9%, and COD removal of 51-98%. Most types of mulches achieved a higher organic matter removal than that achieved by an ordinary septic tank. Bark, peat and wood chips filters removed organic matter better than sand and trickling filters, under similar conditions. Release of filter material and increase in COD in the effluent was reported using some mulch materials. In conclusion, some mulch materials such as bark, peat and woodchips seem to have a great potential for treatment of greywater in robust, low-tech systems. They can be expected to be resilient in dealing with variable low and high organic loads and shock loads. PMID:21902020

  11. Health risk assessment of organic micropollutants in greywater for potable reuse.

    PubMed

    Etchepare, Ramiro; van der Hoek, Jan Peter

    2015-04-01

    In light of the increasing interest in development of sustainable potable reuse systems, additional research is needed to elucidate the risks of producing drinking water from new raw water sources. This article investigates the presence and potential health risks of organic micropollutants in greywater, a potential new source for potable water production introduced in this work. An extensive literature survey reveals that almost 280 organic micropollutants have been detected in greywater. A three-tiered approach is applied for the preliminary health risk assessment of these chemicals. Benchmark values are derived from established drinking water standards for compounds grouped in Tier 1, from literature toxicological data for compounds in Tier 2, and from a Threshold of Toxicological Concern approach for compounds in Tier 3. A risk quotient is estimated by comparing the maximum concentration levels reported in greywater to the benchmark values. The results show that for the majority of compounds, risk quotient values were below 0.2, which suggests they would not pose appreciable concern to human health over a lifetime exposure to potable water. Fourteen compounds were identified with risk quotients above 0.2 which may warrant further investigation if greywater is used as a source for potable reuse. The present findings are helpful in prioritizing upcoming greywater quality monitoring and defining the goals of multiple barriers treatment in future water reclamation plants for potable water production. PMID:25472689

  12. Design and configuration criteria for wetland systems treating greywater.

    PubMed

    Paulo, P L; Begosso, L; Pansonato, N; Shrestha, Roshan R; Boncz, M A

    2009-01-01

    Design and configuration for wetlands treating greywater are usually based on literature data obtained from domestic wastewater operating wetlands. It is very important to determine proper criteria for design and configuration to provide efficiency and minimum maintenance, avoiding bad odour and clogging amongst others, ensuring the acceptance of householders. The aim of this work was to design a wetland system treating greywater for a household and determine whether the chosen criteria were appropriate. Some of the criteria taken into consideration for design and configuration were: quantitative and qualitative characteristics, desired removal of biochemical oxygen demand (BOD) and suspended solids (TSS), substrate and ornamental aspect of the system. The system was composed of a grease trap (kitchen), sedimentation tank, a horizontal flow constructed wetland (HF-CW), intermittent feeding system, and a vertical flow constructed wetland (VF-CW). The results showed that the suggested design and configuration were in accordance with the expected efficiency. Being a compact system, it was susceptible to peak flows, temporarily deteriorating the performance of the HF-CW. The hybrid system, however, showed to cope well with influent fluctuations. The overall performance of the system shows that the removal of turbidity, TSS, COD and BOD were over 88%, reaching 95% removal for both BOD and turbidity. PMID:19844046

  13. Safe greywater reuse to augment water supply and provide sanitation in semi-arid areas of rural India.

    PubMed

    Godfrey, S; Labhasetwar, P; Wate, S; Jimenez, B

    2010-01-01

    Water reuse is recognized as a tool to increase water supply in peri-urban areas of semi-arid and arid regions of the world. However, it is an option rarely explored for rural areas in developing countries, and has not been documented extensively in the scientific literature. This paper presents results from 6 greywater reuse systems which were built with the objective to augment water supply and to provide sanitation in rural low income areas of Madhya Pradesh, India. The systems are based on reclaiming greywater from bathing for the use in toilet flushing and kitchen garden irrigation. The reuse systems were implemented based on the scientific rationale presented in the WHO (2006) guidelines. The paper presents evidence from the operation and evaluation of the greywater treatment plants under field conditions between 2005 and 2008. The paper concludes that greywater is a highly cost effective solution for water scarcity. In this study, reusing greywater resulted in a 60% increase in water availability, a reduction in open defecation and a fourfold increase in food availability. PMID:20861543

  14. Performance of UV disinfection and the microbial quality of greywater effluent along a reuse system for toilet flushing.

    PubMed

    Friedler, Eran; Gilboa, Yael

    2010-04-01

    This paper examines the microbial quality of treated RBC (Rotating Biological Contactor) and MBR (Membrane Bioreactor) light greywater along a continuous pilot-scale reuse system for toilet flushing, quantifies the efficiency of UV disinfection unit, and evaluates the regrowth potential of selected microorganisms along the system. The UV disinfection unit was found to be very efficient in reducing faecal coliforms and Staphylococcus aureus. On the other hand, its efficiency of inactivation of HPC (Heterotrophic Plate Count) and Pseudomonas aeruginosa was lower. Some regrowth occurred in the reuse system as a result of HPC regrowth which included opportunistic pathogens such as P. aeruginosa. Although the membrane (UF) of the MBR system removed all bacteria from the greywater, bacteria were observed in the reuse system due to "hopping phenomenon." The microbial quality of the disinfected greywater was found to be equal or even better than the microbial quality of "clean" water in toilet bowls flushed with potable water (and used for excretion). Thus, the added health risk associated with reusing the UV-disinfected greywater for toilet flushing (regarding P. aeruginosa and S. aureus), was found to be insignificant. The UV disinfection unit totally removed (100%) the viral indicator (F-RNA phage, host: E. coli F(amp)(+)) injected to the treatment systems simulating transient viral contamination. To conclude, this work contributes to better design of UV disinfection reactors and provides an insight into the long-term behavior of selected microorganisms along on-site greywater reuse systems for toilet flushing. PMID:20172592

  15. Reuse potential of laundry greywater for irrigation based on growth, water and nutrient use of tomato

    NASA Astrophysics Data System (ADS)

    Misra, R. K.; Patel, J. H.; Baxi, V. R.

    2010-05-01

    SummaryGreywater is considered as a valuable resource with a high reuse potential for irrigation of household lawns and gardens. However, there are possibilities of surfactant and sodium accumulation in soil from reuse of greywater which may affect agricultural productivity and environmental sustainability adversely. We conducted a glasshouse experiment to examine variation in growth, water and nutrient use of tomato ( Lycopersicon esculentum Mill. cv. Grosse Lisse) using tap water (TW), laundry greywater (GW) and solutions of low and high concentration of a detergent surfactant (LC and HC, respectively) as irrigation treatments. Each treatment was replicated five times using a randomised block design. Measurements throughout the experiment showed greywater to be significantly more alkaline and saline than the other types of irrigation water. Although all plants received 16 irrigations over a period of 9 weeks until flowering, there were little or no significant effects of irrigation treatments on plant growth. Soil water retention following irrigation reduced significantly when plants were irrigated with GW or surfactant solutions on only three of 12 occasions. On one occasion, water use measured as evapotranspiration (ET) with GW irrigation was similar to TW, but it was significantly higher than the plants receiving HC irrigation. At harvest, various components of plant biomass and leaf area for GW irrigated plants were found to be similar or significantly higher than the TW irrigated plants with a common trend of GW ⩾ TW > LC ⩾ HC. Whole-plant concentration was measured for 12 essential plant nutrients (N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, Mo and B) and Na (often considered as a beneficial nutrient). Irrigation treatments affected the concentration of four nutrients (P, Fe, Zn and Na) and uptake of seven nutrients (P, K, Ca, Mg, Na, Fe and B) significantly. Uptake of these seven nutrients by tomato was generally in the order GW ⩾ TW > HC ⩾ LC. GW

  16. Greywater reuse for irrigation: effect on soil properties.

    PubMed

    Travis, Micheal J; Wiel-Shafran, Alit; Weisbrod, Noam; Adar, Eilon; Gross, Amit

    2010-05-15

    A controlled study of the effect of greywater (GW) irrigation on soil properties was conducted. Containers of sand, loam and loess soils were planted with lettuce, and irrigated with fresh water, raw artificial GW or treated artificial GW. Greywater was treated using a recirculating vertical-flow constructed wetland. Soil samples were collected every 10 days for the 40-day duration of the study, and plant growth was measured. Soils were analysed for physicochemical and biological parameters to determine changes caused by the different treatments. It was demonstrated that raw artificial GW significantly increased the development of hydrophobicity in the sand and loam soils, as determined by water droplet penetration time. No significant changes were observed for the loess soil under all treatments. Observed hydrophobicity was correlated with increased oil and grease and surfactant concentrations in the soil. Zeta (zeta) potential of the soils was measured to determine changes in the soil particle surface properties as a result of GW irrigation. A significant change in zeta-potential (less negative) was observed in the raw artificial GW-irrigated sand, whereas no difference was observed in the loam or loess. Soils irrigated with fresh water or treated GW exhibited no increase in hydrophobicity. Fecal coliform bacteria were absent or <10 CFU g(-1) in soils irrigated with fresh water or treated GW, but at least 1 order of magnitude higher in raw artificial GW irrigated soils. Only in the last sampling event and only for the loess soil was plant growth significantly higher for fresh water irrigated vs. raw or treated GW irrigated soils. This study demonstrates that treated GW can be effectively irrigated without detrimental effects on soil or plant growth; however, raw GW may significantly change soil properties that can impact the movement of water in soil and the transport of contaminants in the vadose zone. PMID:20350744

  17. Greywater Disposal Practices in Northern Botswana--The Silent Spring?

    PubMed

    Alexander, Kathleen A; Godrej, Adil

    2015-11-01

    Disposal of greywater is a neglected challenge facing rapidly growing human populations. Here, we define greywater as wastewater that originates from household activities (e.g., washing dishes, bathing, and laundry) but excludes inputs from the toilet. Pollutants in greywater can include both chemical and biological contaminates that can significantly impact human, animal, and environmental health under certain conditions. We evaluate greywater disposal practices in nonsewered, low-income residential areas in Kasane (264 dwellings/ha), Kazungula (100 du/ha), and Lesoma (99 du/ha) villages in Northern Botswana through household surveys (n = 30 per village). Traditional pit latrines were the dominant form of sanitation (69%, n = 90, 95% CI, 59%-79%) while 14% of households did not have access to onsite sanitation (95% CI 0%-22%). While greywater disposal practices varied across villages, respondents in all sites reported dumping greywater into the pit latrine. Frequency varied significantly across villages with the highest level reported in Kasane, where residential density was greatest (p < 0.014, χ² = 9.13, 61% (n = 23, 95% CI 41%-81%), Kazungula 41% (n = 22, 95% CI 20%-62%), Lesoma 13% (95% CI 0%-29%). Disposal of greywater in this manner was reported to limit contamination of the household compound and reduce odors, as well as pit latrine fecal levels. Some respondents reported being directed by local health authorities to dispose of greywater in this manner. Environmentally hazardous chemicals were also dumped directly into the pit latrine to reduce odors. With high household to pit latrine ratios particularly in rental properties (4.2 households, SD = 3.32, range = 15 units, average household size 5.3, SD = 4.4), these greywater and pit latrine management approaches can significantly alter hydraulic loading and leaching of chemicals, microorganisms, and parasites. This can dramatically expand the environmental footprint of pit latrines and greywater

  18. Greywater Disposal Practices in Northern Botswana—The Silent Spring?

    PubMed Central

    Alexander, Kathleen A.; Godrej, Adil

    2015-01-01

    Disposal of greywater is a neglected challenge facing rapidly growing human populations. Here, we define greywater as wastewater that originates from household activities (e.g., washing dishes, bathing, and laundry) but excludes inputs from the toilet. Pollutants in greywater can include both chemical and biological contaminates that can significantly impact human, animal, and environmental health under certain conditions. We evaluate greywater disposal practices in nonsewered, low-income residential areas in Kasane (264 dwellings/ha), Kazungula (100 du/ha), and Lesoma (99 du/ha) villages in Northern Botswana through household surveys (n = 30 per village). Traditional pit latrines were the dominant form of sanitation (69%, n = 90, 95% CI, 59%–79%) while 14% of households did not have access to onsite sanitation (95% CI 0%–22%). While greywater disposal practices varied across villages, respondents in all sites reported dumping greywater into the pit latrine. Frequency varied significantly across villages with the highest level reported in Kasane, where residential density was greatest (p < 0.014, χ2 = 9.13, 61% (n = 23, 95% CI 41%–81%), Kazungula 41% (n = 22, 95% CI 20%–62%), Lesoma 13% (95% CI 0%–29%). Disposal of greywater in this manner was reported to limit contamination of the household compound and reduce odors, as well as pit latrine fecal levels. Some respondents reported being directed by local health authorities to dispose of greywater in this manner. Environmentally hazardous chemicals were also dumped directly into the pit latrine to reduce odors. With high household to pit latrine ratios particularly in rental properties (4.2 households, SD = 3.32, range = 15 units, average household size 5.3, SD = 4.4), these greywater and pit latrine management approaches can significantly alter hydraulic loading and leaching of chemicals, microorganisms, and parasites. This can dramatically expand the environmental footprint of pit latrines and greywater

  19. Potential for nutrient recovery and biogas production from blackwater, food waste and greywater in urban source control systems.

    PubMed

    Kjerstadius, H; Haghighatafshar, S; Davidsson, Å

    2015-01-01

    In the last decades, the focus on waste and wastewater treatment systems has shifted towards increased recovery of energy and nutrients. Separation of urban food waste (FW) and domestic wastewaters using source control systems could aid this increase; however, their effect on overall sustainability is unknown. To obtain indicators for sustainability assessments, five urban systems for collection, transport, treatment and nutrient recovery from blackwater, greywater and FW were investigated using data from implementations in Sweden or northern Europe. The systems were evaluated against their potential for biogas production and nutrient recovery by the use of mass balances for organic material, nutrients and metals over the system components. The resulting indicators are presented in units suitable for use in future sustainability studies or life-cycle assessment of urban waste and wastewater systems. The indicators show that source control systems have the potential to increase biogas production by more than 70% compared with a conventional system and give a high recovery of phosphorus and nitrogen as biofertilizer. The total potential increase in gross energy equivalence for source control systems was 20-100%; the greatest increase shown is for vacuum-based systems. PMID:25608932

  20. Parameters affecting greywater quality and its safety for reuse.

    PubMed

    Maimon, Adi; Friedler, Eran; Gross, Amit

    2014-07-15

    Reusing greywater (GW) for on-site irrigation is becoming a common practice worldwide. Alongside its benefits, GW reuse might pose health and environmental risks. The current study assesses the risks associated with on-site GW reuse and the main factors affecting them. GW from 34 households in Israel was analyzed for physicochemical parameters, Escherichia coli (as an indicator for rotavirus), Pseudomonas aeruginosa and Staphylococcus aureus. Each participating household filled out a questionnaire about their GW sources, treatment and usages. Quantitative microbial risk assessment (QMRA) was performed based on the measured microbial quality, and on exposure scenarios derived from the questionnaires and literature data. The type of treatment was found to have a significant effect on the quality of the treated GW. The average E. coli counts in GW (which exclude kitchen effluent) treated by professionally-designed system resulted in acceptable risk under all exposure scenarios while the risk from inadequately-treated GW was above the accepted level as set by the WHO. In conclusion, safe GW reuse requires a suitable and well-designed treatment system. A risk-assessment approach should be used to adjust the current regulations/guidelines and to assess the performance of GW treatment and reuse systems. PMID:24751591

  1. 75 FR 13679 - Treatment of Overall Foreign and Domestic Losses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-23

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Part 1 Treatment of Overall Foreign and Domestic Losses CFR Correction In Title 26 of the Code of Federal Regulations, Part 1 (Sec. Sec. 1.851 to 1.907), revised as of April...

  2. 78 FR 18235 - Treatment of Overall Foreign and Domestic Losses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Part 1 Treatment of Overall Foreign and Domestic Losses CFR Correction 0 In Title 26 of the Code of Federal Regulations, Part 1 (Sec. Sec. 1.851 to 1.907), revised as of April...

  3. 1. DOMESTIC WATER SUPPLY TREATMENT HOUSE, ON PENSTOCK ABOVE SAR1. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. DOMESTIC WATER SUPPLY TREATMENT HOUSE, ON PENSTOCK ABOVE SAR-1. VIEW TO NORTWEST. - Santa Ana River Hydroelectric System, SAR-1 Domestic Water Supply Treatment House, Redlands, San Bernardino County, CA

  4. A monitoring of environmental effects from household greywater reuse for garden irrigation.

    PubMed

    Mohamed, Radin Maya Saphira Radin; Kassim, Amir Hashim Mohd; Anda, Martin; Dallas, Stewart

    2013-10-01

    The option of reusing greywater is proving to be increasingly attractive to address the water shortage issue in many arid and semiarid countries. Greywater represents a constant resource, since an approximately constant amount of greywater is generated from kitchen, laundries, bathroom in every household daily, independent of the weather. However, the use of greywater for irrigation in particular for household gardening may pose major hazards that have not been studied thoroughly. In this study, a 1-year monitoring was conducted in four selected households in Perth, Western Australia. The aim of the monitoring works is to investigate the variability in the greywater flow and quality, and to understand its impact in the surrounding environments. Case studies were selected based on different family structure including number, ages of the occupants, and greywater system they used. Samples of greywater effluent (showers, laundries, bathtub, and sinks), leachate, soil, and plants at each case study were collected between October 2008 and December 2009 which covered the high (spring/summer) and low (autumn/winter) production of greywater. Physical and chemical tests were based on the literature and expected components of laundry and bathroom greywater particularly on greywater components likely to have detrimental impacts on soils, plants, and other water bodies. Monitoring results showed the greywater quality values for BOD, TSS, and pH which sometimes fell outside the range as stipulated in the guidelines. The soil analyses results showed that salinity, SAR, and the organic content of the soil increased as a function of time and affected the plant growth. Nutrient leaching or losses from soil irrigated with greywater shows the movement of nutrients and the sole impact from greywater in uncontrolled plots in case studies is difficult to predicted due to the influence of land dynamics and activities. Investigative and research monitoring was used to understand greywater

  5. Field study of the composition of greywater and comparison of microbiological indicators of water quality in on-site systems.

    PubMed

    Leonard, Margaret; Gilpin, Brent; Robson, Beth; Wall, Katrina

    2016-08-01

    Thirty on-site greywater systems were sampled to determine greywater characteristics and practices in the field. Kitchen greywater was present at eight sites and urine was included at seven sites. These non-traditional sources resulted in significantly higher concentrations of enterococci and 5-day biochemical oxygen demand (BOD5) in greywater. Even with the removal of these sources, the concentrations of microbial indicators indicated high levels of contamination could occur across all greywater sources, including "light" greywater. Using multiple microbial indicators showed that all samples had the potential for faecal contamination. Bacteroidales markers were confirmed in treated greywater and in each greywater source, highlighting the potential for human faecal contamination. Although Escherichia coli was absent in treated greywater recycled to the house, other microbial indicators were present; hence, caution is required in using E. coli concentrations as the sole indicator of microbiological water quality. High BOD5 or total suspended solid concentrations exceeded the levels recommended for effective disinfection. Subsurface irrigation, which is assumed to provide a five-log reduction in exposure, is a suitable reuse option for non-disinfected greywater. Only half the occupants had a good understanding of their greywater systems and 25 % of systems were poorly maintained. Elevated microbial indicator contamination of greywater sludge is a potential hazard during maintenance. PMID:27435622

  6. Performance Evaluation of Integrated Constructed Wetland for Domestic Wastewater Treatment.

    PubMed

    Sehar, Shama; Naz, Iffat; Khan, Sumera; Naeem, Sana; Perveen, Irum; Ali, Naeem; Ahmed, Safia

    2016-03-01

    Simple, budget friendly, laboratory-scale integrated constructed wetland (ICW) was designed to assess domestic wastewater treatment performance at a loading rate of 75 mm/d, planted with native plant species: Veronica-angallis aquatica and compared with non-vegetative control system at various residence times of 4, 8, 12, 16, 20, 24, and 28 days. Results revealed that the vegetated ICW demonstrated superior performance over non-vegetated control: 69.12 vs 17.12%, 67.77 vs 16.04%, 68 vs 16.48%, 71.19 vs 6.56%, 71.54 vs 14.80%, and 72.04 vs 11.41% for total dissolved solids, total suspended solids, phosphates (PO4(-)), sulfate (SO4(-)), nitrate (NO3(-)), and nitrite (NO2(-)), respectively, at 20 days residence times. Reduction in bacterial counts (2.79 × 10(4) CFU/mL) and fecal pathogens (345.5 MPN index/100 mL) was observed in V. aquatica at 20 days residence time. Therefore, the present study highlights not only the presence of vegetation but also appropriate residence time in constructed wetlands for better performances. PMID:26931539

  7. [Treatment characteristics of saline domestic wastewater by constructed wetland].

    PubMed

    Gao, Feng; Yang, Zhao-Hui; Li, Chen; Jin, Wei-Hong; Deng, Yi-Bing

    2012-11-01

    A series of experiments were conducted to evaluate the feasibility of using constructed wetland (CW) to remove pollutants from saline domestic sewage. The experimental results indicated that the effects of salinity on the contaminant removal were insignificant when the influent salinities of the CWs were less than or equal to 1.5%. For the influent salinity of 0%, 0.5%, 1.0% and 1.5%, the average removal rates of the CWs were found to be above 68.3% for COD and above 66.1% for NH4(+) -N. When the influent salinity was increased to 2.0%, the individual numbers of microorganisms in the CW reduced obviously. It was similar to the change of the soil enzyme activity in the CW. Then the removal efficiency of the CW also dropped significantly. The average removal rate of COD and NH4(+) -N dropped to 52.9% and 50.3%, respectively. The effects of HRT on the treatment performance of CW under the saline condition of 1.5% were also investigated in this study. And the results showed that nitrogen removal was more greatly affected by HRT than organic matter removal. The NH4(+) -N removal efficiency in CW decreased from 65.1% -78.2% to 47.1% when the HRT of the CW varied from 3-5 d to 2 d. PMID:23323411

  8. Domestic wastewater treatment in a novel sequencing batch biofilm filter.

    PubMed

    Ji, Bin; Wei, Li; Chen, Dan; Wang, Hongyu; Li, Zhenhua; Yang, Kai

    2015-07-01

    Biological treatment of domestic sewage low C/N ratio was accomplished in a pilot-scale sequencing batch biofilm filter (SBBF). The novel hybrid bioreactor consisted of bio-band in the upper and anthracite filter media in the bottom, which combined a sequencing batch biofilm reactor (SBBR) with a biological filter. The average removal efficiency values of chemical oxygen demand (COD), ammonium nitrogen (NH4 (+)-N), total nitrogen (TN), and total phosphorus (TP) were 89.4, 83.3, 62.9, and 48.7%, respectively. A 454-pyrosequencing technology was employed to investigate the microbial communities of the influent (J1) and the biofilm (J2) on the bio-band on day 40. Pyrosequencing analysis of the 16S rRNA gene revealed the community of the biofilm consisted of Gammaproteobacteria (48.6%), Planctomycetacia (18.0%), Alphaproteobacteria (13.7%), Clostridia (9.6%), Desulfonatronum (18.5%), Actinobacteria (1.9%), and Bacilli (1.7%), accounting for 93.6% of total operational taxonomic units at genera level. Acinetobacter tjernbergiae and Acinetobacter lwoffii were the most abundant species, suggesting that denitrifying phosphorus removal was achieved in the SBBF. PMID:25967659

  9. Counselor Treatment of Coexisting Domestic Violence and Substance Abuse: A Qualitative Study.

    ERIC Educational Resources Information Center

    Chartas, Nicole D.; Culbreth, John R.

    2001-01-01

    This study explored the philosophical issues hindering the linkage of substance abuse and domestic violence treatment. Results suggest that counselors tend to use treatment models that could not concurrently assign responsibility and address either present or past victimization. (Author)

  10. Highly effective degradation of sodium dodecylbenzene sulphonate and synthetic greywater by Fenton-like reaction over zerovalent iron-based catalyst.

    PubMed

    Zhu, Shi-Ni; Wang, Chao; Yip, Alex C K; Tsang, Daniel C W

    2015-01-01

    There is an increasing interest to recycle greywater for meeting non-portable water demand. However, linear alkylbenzene sulphonates (a form of anionic surfactants) that are commonly found in greywater are less biodegradable at moderate to high concentrations. A fenton-like system is a relatively economic advanced oxidation process that can potentially be used for surfactant degradation in greywater treatment. This study investigated the feasibility of zerovalent iron (ZVI)-mediated Fenton's oxidation of sodium dodecylbenzene sulphonate (SDBS) using Fe0/H2O2 and Fe2+/Fe0/H2O2 systems under a range of operating conditions. For the Fe0/H2O2 binary system, the initial pH value and Fe0 dosage played important roles in final degradation efficiency. For the Fe2+/Fe0/H2O2 ternary systems, a small amount of Fe2+ (0.5-1.7 mM) contributed a synergistic effect to promote iron recycling and SDBS degradation. Approximately, 90% of SDBS mineralization efficiency was accomplished within 15 min at a pH range from 3.0 to 6.5, using 18 mM Fe0 and 15 mM H2O2. However, the removal kinetics was rate-limited by Fe2+ dissolution from the ZVI surfaces. The Fenton-like process of the Fe2+/Fe0/H2O2 ternary system also presents a promising treatment method for synthetic greywater, in which 90% TOC removal was achieved within the first 10 min; 78% COD and 91% BOD5 were achieved after 120 min of reaction. PMID:25424128

  11. Addressing Water Consumption of Evaporative Coolers with Greywater

    SciTech Connect

    Sahai, Rashmi; Shah, Nihar; Phadke, Amol

    2012-07-01

    Evaporative coolers (ECs) provide significant gains in energy efficiency compared to vapor compression air conditioners, but simultaneously have significant onsite water demand. This can be a major barrier to deployment in areas of the world with hot and arid climates. To address this concern, this study determined where in the world evaporative cooling is suitable, the water consumption of ECs in these cities, and the potential that greywater can be used reduce the consumption of potable water in ECs. ECs covered 69percent of the cities where room air conditioners are may be deployed, based on comfort conditions alone. The average water consumption due to ECs was found to be 400 L/household/day in the United States and Australia, with the potential for greywater to provide 50percent this amount. In the rest of the world, the average water consumption was 250 L/household/day, with the potential for greywater to supply 80percent of this amount. Home size was the main factor that contributed to this difference. In the Mediterranean, the Middle East, Northern India, and the Midwestern and Southwestern United States alkalinity levels are high and water used for bleeding will likely contribute significantly to EC water consumption. Although technically feasible, upfront costs for household GW systems are currently high. In both developed and developing parts of the world, however, a direct EC and GW system is cost competitive with conventional vapor compression air conditioners. Moreover, in regions of the world that face problems of water scarcity the benefits can substantially outweigh the costs.

  12. Treatment of mixed domestic-industrial wastewater using cyanobacteria.

    PubMed

    El-Bestawy, Ebtesam

    2008-11-01

    Alexandria Sanitary Drainage Company (ASDCO), Alexandria, Egypt has two primary treatment plants, the eastern and the western wastewater treatment plants (EWTP and WWTP) that receive mixed domestic-industrial influents and discharge into L. Mariut. The lake is subjected therefore to severe levels of pollution and dominated by members of cyanobacteria that can cope with the high pollution load in the lake water. Isolation and utilization of the locally generated cyanobacterial biomass for remediation processes of highly toxic pollutants offers a very efficient and cheap tool for governmental or private industrial activities in Alexandria and will generate a source of revenue in Egyptian localities. The main objective of the present study was to investigate the biodegradation and biosorption capacity of some potential cyanobacterial species dominating the lake ecosystem toward organic and inorganic contaminants polluting the primary-treated effluents of the EWTP and WWTP. The primary effluents were subjected to biological treatment using three axenic cyanobacterial strains (Anabaena oryzae, Anabaena variabilis and Tolypothrix ceytonica) as batch system for 7 days. Removal efficiencies (RE) of the different contaminants were evaluated and compared. Results confirmed the high efficiencies of the investigated species for the removal of the target contaminants which were species and contaminant-dependent. BOD5 and COD recorded 89.29 and 73.68% as maximum RE(s) achieved by Anabaena variabilis and Anabaena oryzae, respectively. The highest RE of the TSS recorded 64.37% achieved by Tolypothrix ceytonica, while 38.84% was recorded as the highest TSD RE achieved by Anabaena variabilis. Tolypothrix ceytonica also exhibited the highest RE for FOG recorded 93.75%. Concerning the contaminant metals, Tolypothrix ceytonica showed the highest biosorption capacity where 86.12 and 94.63% RE were achieved for Zn and Cu, respectively. In conclusion, results of the present study

  13. A novel fixed fibre biofilm membrane process for on-site greywater reclamation requiring no fouling control.

    PubMed

    Jabornig, Simon; Podmirseg, Sabine Marie

    2015-03-01

    On-site greywater treatment and reuse in urban areas bears the potential to reduce huge quantities of wastewater and lower freshwater shortages. Until now dissemination of small, single household applications has been rather limited as simple and high quality water producing, but also cost-effective treatment units have not been developed so far. This paper proposes a new process, based on a concurrently working hollow-fibre membrane as fixed biofilm support and filtration device. Bioreactor characteristics, influence of different aeration rates, membrane flux development, as well as structure and composition of biofilm were monitored to evaluate the performance of the tested pilot unit. The introduced process achieved international water reuse guidelines, worked soundly and could, compared to conventional micro MBR, significantly reduce energy demand (<1.4 kWh m(-3)). Fouling control by air scouring and chemical cleaning was not required once flux had stabilized. The biofilm analysis showed a porous, spongy-like structure. Microbiological investigation revealed a community of sheathed bacteria and nematodes that could play an important role in the flux stabilisation effect. In general, the study confirmed the suitability of the presented process for greywater treatment and provides valuable design data for future optimization and systematic analysis. PMID:25220525

  14. Evaluating greywater reuse potential for sustainable water resources management in Oman.

    PubMed

    Jamrah, Ahmad; Al-Futaisi, Ahmed; Prathapar, Sanmugan; Harrasi, Ali Al

    2008-02-01

    This study aims to evaluate the potential of greywater availability in Muscat Governorate in the Sultanate of Oman, to establish a methodology for greywater quantity estimation, to test greywater quality in order to assess reuse potential, and to examine public acceptance for reuse.Total fresh water consumption and greywater generation from different household sources were measured by water meters in five selected households during summer and winter. Additionally, a survey was designed and conducted in five administrative areas of Muscat Governorate, with the objective of testing a methodology for estimating greywater generation potential in these areas. Collected data were compared with that used by the Ministry of Housing, Electricity and Water, Sultanate of Oman. The survey covered a total of 169 houses and 1,365 people. Greywater samples were collected and analyzed from showers, laundries, kitchens and sinks in some of these households to determine their water quality parameters. Statistical analysis results indicated that there is no significant variance in the total fresh water consumption between data used by the ministry and those measured and estimated during this study, highlighting the applicability of the tested method. The study concluded that the average per capita greywater generation rate is 151 Lpcd. Greywater production ranged from 80 to 83% of the total fresh water consumption and most of the greywater is generated from showers. Further, 55 to 57% of the greywater generated in a typical Omani household originated from the shower, 28 to 33% originated from the kitchen, 6 to 9% originated from laundry, and 5 to 7% originated from sink, which constitutes approximately 81% of the total fresh water consumption. The physical, chemical, and biological analyses of the grab samples revealed that greywater contains significant levels of suspended solids, inorganic constituents, total organic carbon, chemical and biochemical oxygen demands, total Coliforms

  15. Greywater use in Israel and worldwide: standards and prospects.

    PubMed

    Oron, Gideon; Adel, Mike; Agmon, Vered; Friedler, Eran; Halperin, Rami; Leshem, Ehud; Weinberg, Daniel

    2014-07-01

    Water shortage around the world enhanced the search for alternative sources. Greywater (GW) can serve as a solution for water demands especially in arid and semi-arid zones. However, issues considered which include acceptability of GW segregation as a separate water treated stream, allowing its use onsite. Consequently, it is the one of next forthcoming water resources that will be used, primarily in the growing mega-cities. It will be even more rentable when combined with the roof runoff water harvesting and condensing water from air-conditioning systems. Reuse of GW is as well beneficial in the mega-cities subject to the high expenses associated with wastewater and fresh water conveyance in the opposite direction. The main problem associated with GW reuse is the quality of the water and the targeted reuse options. At least two main options can be identified: the public sector that is ready to reuse the GW and the private sector which raises extra issues related to the reuse risks. These risk stems from the on yard use of GW, relatively close to the household location. The main focus of the Israeli guidelines for GW use is on the private and single house. The problem is less rigorous in public facilities, where the amounts are relatively large and the raw GW is relatively diluted. The two main principles adopted for reuse are: (i) greywater can be minimally treated since it differs from the black wastes, and; (ii) no contact exists with the resident around. The aggravated standards are an indication of the sensitivity issues related to the problem. PMID:24747140

  16. Bioremediation of acid mine drainage coupled with domestic wastewater treatment.

    PubMed

    Sánchez-Andrea, Irene; Triana, David; Sanz, Jose L

    2012-01-01

    Acid mine drainage (AMD) - characterized by high acidity and elevated sulfate and metal concentrations - represents a big environmental concern. Biological sulfate reduction has become an alternative to the classical physicochemical methods. In this study, domestic wastewater (DW) was tested as a cost-effective carbon-source for the remediation of AMD. Sediments from Tinto River, an extreme acidic environment with an elevated concentration of metals, were used as inoculum. Three anaerobic bioreactors with different microbial supports were fed with a 1:10 (v:v) mixture of synthetic AMD:DW. Around 50% of the organic matter present in the DW co-precipitated with the metals from the AMD previous to feeding the reactor. Therefore, the reactors had to be supplemented with an extra carbon-source (acetate) to achieve higher S elimination. Elevated removal efficiencies of chemical oxygen demand (COD) (>88%), sulfate (>75%), Fe (>85%) and other dissolved metals (>99% except for Mn) were achieved. Bacterial communities were examined through denaturing gradient gel electrophoresis and scanning electron microscopy. Higher biodiversity was found in the bioreactors compared with that of the inoculum. Dominant species belong to two metabolic groups: fermentative (Clostridium spp., Delftia spp., Paludibacter spp. and Pelotomaculum spp.) and sulfate-reducing bacteria (Desulfomonile spp., Desulfovibrio spp., Desulfosporosinus spp. and Desulfotomaculum spp.). PMID:23032774

  17. Psychrophilic anaerobic membrane bioreactor treatment of domestic wastewater.

    PubMed

    Smith, Adam L; Skerlos, Steven J; Raskin, Lutgarde

    2013-03-15

    A bench-scale anaerobic membrane bioreactor (AnMBR) equipped with submerged flat-sheet microfiltration membranes was operated at psychrophilic temperature (15 °C) treating simulated and actual domestic wastewater (DWW). Chemical oxygen demand (COD) removal during simulated DWW operation averaged 92 ± 5% corresponding to an average permeate COD of 36 ± 21 mg/L. Dissolved methane in the permeate stream represented a substantial fraction (40-50%) of the total methane generated by the system due to methane solubility at psychrophilic temperatures and oversaturation relative to Henry's law. During actual DWW operation, COD removal averaged 69 ± 10%. The permeate COD and 5-day biochemical oxygen demand (BOD(5)) averaged 76 ± 10 mg/L and 24 ± 3 mg/L, respectively, indicating compliance with the U.S. EPA's standard for secondary effluent (30 mg/L BOD(5)). Membrane fouling was managed using biogas sparging and permeate backflushing and a flux greater than 7 LMH was maintained for 30 days. Comparative fouling experiments suggested that the combination of the two fouling control measures was more effective than either fouling prevention method alone. A UniFrac based comparison of bacterial and archaeal microbial communities in the AnMBR and three different inocula using pyrosequencing targeting 16S rRNA genes suggested that mesophilic inocula are suitable for seeding psychrophilic AnMBRs treating low strength wastewater. Overall, the research described relatively stable COD removal, acceptable flux, and the ability to seed a psychrophilic AnMBR with mesophilic inocula, indicating future potential for the technology in practice, particularly in cold and temperate climates where DWW temperatures are low during part of the year. PMID:23295067

  18. Metered oxygen supply aids treatment of domestic sewage

    NASA Technical Reports Server (NTRS)

    Weliky, N.; Hooper, T. J.; Silverman, H. P.

    1972-01-01

    Microbiological fixed-bed process was developed in which supplementary oxygen required by microbial species is supplied by electrochemical device. Rate of addition of oxygen to waste treatment process is controlled to maintain aerobic metabolism and prevent anaerobic metabolisms which produce odorous or toxic products.

  19. Hazardous solid waste from domestic wastewater treatment plants.

    PubMed Central

    Harrington, W M

    1978-01-01

    The treatment of liquid wastes in municipal sewage treatment plants creates significant quantities of solid residue for disposal. The potential hazard from these wastes requires that their characteristics be determined accurately to develop environmentally sound management criteria. It is readily recognized that the sludge characteristics vary with the type and degree of industrial activity within a wastewater collection system and that these characteristics play a significant role in determining whether the material has potential for beneficial reuse or if it must be directed to final disposal. This paper offers an overview of past and present practices of sewage sludge disposal, an indication of quantities produced, and experience with beneficial reuse. An estimated range of costs involved, expected environmental effects and potential for continued use is offered for each disposal or reuse system discussed. PMID:738239

  20. Removal Of Endocrine Disrupting Chemicals By A Constructed Wetland For On-Site Domestic Wastewater Treatment

    EPA Science Inventory

    Research has shown that domestic and industrial wastewater can be a source of endocrine disrupting chemicals (EDCs) to the environment. Much of this research has focused on municipal and industrial centralized wastewater treatment plants (WWTPs). These WWTPs have been shown to ...

  1. ESTIMATES OF GLOBAL GREENHOUSE GAS EMISSIONS FROM INDUSTRIAL AND DOMESTIC WASTEWATER TREATMENT

    EPA Science Inventory

    The report summarizes the findings of field tests and provides emission factors for methane (CH4) and nitrous oxide (N2O) from wastewater treatment (WWT). It also includes country-specific activity data on industrial and domestic WWT which were used to develop country-specific em...

  2. EVALUATION OF ESTROGENIC ACTIVITY FROM A MUNICIPAL WASTEWATER TREATMENT PLANT WITH PREDOMINANTLY DOMESTIC INPUT

    EPA Science Inventory

    The purpose of this study was to survey estrogenic releases from two primarily domestic wastewater treatment plants over three seasons (1996-1999). Mature male channel catfish were maintained at two sites within each WWTP and a reference site for 21 days. Estrogenic activity of e...

  3. Two years of the operation of a domestic MBR wastewater treatment plant

    NASA Astrophysics Data System (ADS)

    Pikorová, Tina

    2012-06-01

    The paper evaluates the results of data obtained from two years of observing an actual domestic wastewater treatment plant (WWTP) with an immersed membrane module. The domestic MBR (membrane bioreactor) WWTP was linked to a dwelling with four residents. Two different commercial flat sheet membrane modules were investigated. The membrane modules, as well as the whole WWTP, were tested with different fluxes as well as the response of the membrane and activated sludge to different conditions, such as actual peak wastewater flows, extremes temperatures (a winter below 5 °C), and high pH values.

  4. Aerobic sludge granulation at high temperatures for domestic wastewater treatment.

    PubMed

    Ab Halim, Mohd Hakim; Nor Anuar, Aznah; Azmi, Siti Izaidah; Jamal, Nur Syahida Abdul; Wahab, Norhaliza Abdul; Ujang, Zaini; Shraim, Amjad; Bob, Mustafa M

    2015-06-01

    With inoculum sludge from a conventional activated sludge wastewater treatment plant, three sequencing batch reactors (SBRs) fed with synthetic wastewater were operated at different high temperatures (30, 40 and 50±1°C) to study the formation of aerobic granular sludge (AGS) for simultaneous organics and nutrients removal with a complete cycle time of 3h. The AGS were successfully cultivated with influent loading rate of 1.6CODg(Ld)(-1). The COD/N ratio of the influent wastewater was 8. The results revealed that granules developed at 50°C have the highest average diameter, (3.36mm) with 98.17%, 94.45% and 72.46% removal efficiency observed in the system for COD, ammonia and phosphate, respectively. This study also demonstrated the capabilities of AGS formation at high temperatures which is suitable to be applied for hot climate conditions. PMID:25851807

  5. Exposure to synthetic greywater inhibits amoebae encystation and alters expression of Legionella pneumophila virulence genes

    EPA Science Inventory

    Water conservation efforts have focused on greywater (GW) usage, especially for applications that do not require potable water quality. However, there is a need to better understand environmental pathogens and their free-living amoebae (FLA) hosts within GW. Using synthetic gre...

  6. Multi-objective evolutionary optimization for greywater reuse in municipal sewer systems.

    PubMed

    Penn, Roni; Friedler, Eran; Ostfeld, Avi

    2013-10-01

    Sustainable design and implementation of greywater reuse (GWR) has to achieve an optimum compromise between costs and potable water demand reduction. Studies show that GWR is an efficient tool for reducing potable water demand. This study presents a multi-objective optimization model for estimating the optimal distribution of different types of GWR homes in an existing municipal sewer system. Six types of GWR homes were examined. The model constrains the momentary wastewater (WW) velocity in the sewer pipes (which is responsible for solids movement). The objective functions in the optimization model are the total WW flow at the outlet of the neighborhoods sewer system and the cost of the on-site GWR treatment system. The optimization routing was achieved by an evolutionary multi-objective optimization coupled with hydrodynamic simulations of a representative sewer system of a neighborhood located at the coast of Israel. The two non-dominated best solutions selected were the ones having either the smallest WW flow discharged at the outlet of the neighborhood sewer system or the lowest daily cost. In both solutions most of the GWR types chosen were the types resulting with the smallest water usage. This lead to only a small difference between the two best solutions, regarding the diurnal patterns of the WW flows at the outlet of the neighborhood sewer system. However, in the upstream link a substantial difference was depicted between the diurnal patterns. This difference occurred since to the upstream links only few homes, implementing the same type of GWR, discharge their WW, and in each solution a different type of GWR was implemented in these upstream homes. To the best of our knowledge this is the first multi-objective optimization model aimed at quantitatively trading off the cost of local/onsite GW spatially distributed reuse treatments, and the total amount of WW flow discharged into the municipal sewer system under unsteady flow conditions. PMID:23932104

  7. Progress for the treatment of the combustible portion of domestic waste for briquetting and apparatus therefor

    SciTech Connect

    Riemann, H.H.; Sonneschein, H.

    1984-05-01

    A method and apparatus for the treatment of the combustible portion of crushed domestic waste is disclosed. The waste is pre-dried and separated from dense-medium material such as metal and glass prior to processing. A dried waste moisture level of about 8-10% is maintained throughout the process. High heat value briquets are produced without the addition of a bonding agent by sifting out fine inert material and plastic material prior to briquetting.

  8. Perspectives on anaerobic membrane bioreactor treatment of domestic wastewater: a critical review.

    PubMed

    Smith, Adam L; Stadler, Lauren B; Love, Nancy G; Skerlos, Steven J; Raskin, Lutgarde

    2012-10-01

    Interest in increasing the sustainability of water management is leading to a reevaluation of domestic wastewater (DWW) treatment practices. A central goal is to reduce energy demands and environmental impacts while recovering resources. Anaerobic membrane bioreactors (AnMBRs) have the ability to produce a similar quality effluent to aerobic treatment, while generating useful energy and producing substantially less residuals. This review focuses on operational considerations that require further research to allow implementation of AnMBR DWW treatment. Specific topics include membrane fouling, the lower limits of hydraulic retention time and temperature allowing for adequate treatment, complications with methane recovery, and nutrient removal options. Based on the current literature, future research efforts should focus on increasing the likelihood of net energy recovery through advancements in fouling control and development of efficient methods for dissolved methane recovery. Furthermore, assessing the sustainability of AnMBR treatment requires establishment of a quantitative environmental and economic evaluation framework. PMID:22608937

  9. Domestic wastewater treatment in waste stabilization ponds for irrigation in Mendoza, Argentina: policies and challenges.

    PubMed

    Vélez, O R; Fasciolo, G E; Bertrano, A V

    2002-01-01

    Arid areas call for imaginative water management solutions to avoid the dangers of water shortages. Growing demands of water for domestic and industrial uses decrease the availability of water for agriculture. It therefore becomes necessary to set up a policy for the use of domestic effluents. For the province of Mendoza, Argentina, with 1,500,000 inhabitants, a master plan was designed as of 1991 for the treatment of domestic effluents and subsequent disposal for irrigation. The guidelines set up by WHO for the use of wastewater in agricultural applications were taken into consideration. At present, the Province of Mendoza has available projects which are either complete, in execution or in the bidding process, entailing secondary treatment capacity with reuse of 320,000 cubic metres/day and an estimated possible irrigation area of 10,000 hectares. With this infrastructure, some strategic lines of action are recommended to establish a policy for the agricultural use of wastewater: (a) to program the use of treated wastewater to avoid discharges to irrigation flows; (b) to develop an institutional scheme for the efficient and safe use of these waters; and (c) develop scientific and technologic know-how to accompany the updated policies. PMID:11833726

  10. Domestic wastewater treatment with purple phototrophic bacteria using a novel continuous photo anaerobic membrane bioreactor.

    PubMed

    Hülsen, Tim; Barry, Edward M; Lu, Yang; Puyol, Daniel; Keller, Jürg; Batstone, Damien J

    2016-09-01

    A key future challenge of domestic wastewater treatment is nutrient recovery while still achieving acceptable discharge limits. Nutrient partitioning using purple phototrophic bacteria (PPB) has the potential to biologically concentrate nutrients through growth. This study evaluates the use of PPB in a continuous photo-anaerobic membrane bioreactor (PAnMBR) for simultaneous organics and nutrient removal from domestic wastewater. This process could continuously treat domestic wastewater to discharge limits (<50 mgCOD L(-1), 5 mgN L(-1), 1.0 mgP L(-1)). Approximately 6.4 ± 1.3 gNH4-N and 1.1 ± 0.2 gPO4-P for every 100 gSCOD were removed at a hydraulic retention time of 8-24 h and volumetric loading rates of 0.8-2.5 COD kg m(3) d(-1). Thus, a minimum of 200 mg L(-1) of ethanol (to provide soluble COD) was required to achieve these discharge limits. Microbial community through sequencing indicated dominance of >60% of PPB, though the PPB community was highly variable. The outcomes from the current work demonstrate the potential of PPB for continuous domestic (and possibly industrial) wastewater treatment and nutrient recovery. Technical challenges include the in situ COD supply in a continuous reactor system, as well as efficient light delivery. Addition of external (agricultural or fossil) derived organics is not financially nor environmentally justified, and carbon needs to be sourced internally from the biomass itself to enable this technology. Reduced energy consumption for lighting is technically feasible, and needs to be addressed as a key objective in scaleup. PMID:27232993

  11. Low temperature treatment of domestic wastewater by purple phototrophic bacteria: Performance, activity, and community.

    PubMed

    Hülsen, Tim; Barry, Edward M; Lu, Yang; Puyol, Daniel; Batstone, Damien J

    2016-09-01

    Low wastewater temperatures affect microbial growth rates and microbial populations, as well as physical chemical characteristics of the wastewater. Wastewater treatment plant design needs to accommodate changing temperatures, and somewhat limited capacity is a key criticism of low strength anaerobic treatment such as Anaerobic Membrane Bioreactors (AnMBR). This study evaluates the applicability of an alternative platform utilizing purple phototrophic bacteria for low temperature domestic wastewater treatment. Two photo-anaerobic membrane bioreactors (PAnMBR) at ambient (22 °C) and low temperatures (10 °C) were compared to fully evaluate temperature response of critical processes. The results show good functionality at 10 °C in comparison with ambient operation. This enabled operation at 10 °C to discharge limits (TCOD < 100 mg L(-1); TN < 10 mg L(-1) and TP < 1 mg L(-1)) at a HRT < 1 d. While capacity of the system was not limited, microbial community showed a strong shift to a far narrower diversity, almost complete dominance by PPB, and of a single Rhodobacter spp. compared to a more diverse community in the ambient reactor. The outcomes of the current work enable applicability of PPB for domestic wastewater treatment to a broad range of regions. PMID:27235774

  12. The Comparative Evaluation of the Performance of Two Phytoremediation Systems for Domestic Wastewater Treatment.

    PubMed

    Valipour, A; Azizi, Sh; Raman, V K; Jamshidi, S; Hamnabard, N

    2014-07-01

    The constructed wetlands as well engineered techniques have been used effectively for phytoremediation of wastewater and pollution control during the last decades. In these technologies, the naturally occurring processes of plants alongside micro-organisms present in the bio-film attached to the roots, soil substrate and water column degrade the organic pollutants. The study seeks to compare the potential use of Phragmites sp. reed bed and floating macrophyte water hyacinth (Eichhornia crassipes) system for domestic wastewater treatment. The sewage treatment performance is evaluated as 80% & 76% chemical oxygen demand (COD), 90% & 87% biological oxygen demand (BOD5), 24% & 18% total dissolved solids (TDS), 69% & 67% total suspended solids (TSS), 12% & 5% Chlorides, 73% & 69% ammonia nitrogen (NH3-N), 42% & 31% phosphate (PO4-P), 93% & 91% most probable number (MPN) and 95% & 92% total viable count (TVC) reduction at optimum hydraulic retention time (HRT) of 24 & 43 h in Phragmites sp. and water hyacinth systems, respectively. Likewise, the floating macrophyte pond contrary to reed bed process shows insignificant pollutant diminution at 24 h HRT. This paper also highlights the microbial population present through the wetland systems by estimation of total viable count (TVC). The botanical aspect with reference to the plant growth is shown a significant increase in vegetation yield. The overall studies indicate the better treatment efficiency by preferred Phragmites sp. root zone system at low foot print area for domestic wastewater. PMID:26563084

  13. Soil infiltration bioreactor incorporated with pyrite-based (mixotrophic) denitrification for domestic wastewater treatment.

    PubMed

    Kong, Zhe; Li, Lu; Feng, Chuanping; Chen, Nan; Dong, Shanshan; Hu, Weiwu

    2015-01-01

    In this study, an integrated two-stage soil infiltration bioreactor incorporated with pyrite-based (mixotrophic) denitrification (SIBPD) was designed for domestic wastewater treatment. Benefited from excellent adsorption ability and water-permeability, soil infiltration could avoid clogging, shorten operating time and lower maintenance cost. Respiration and nitrification were mostly engaged in aerobic stage (AES), while nitrate was majorly removed by pyrite-based mixotrophic denitrification mainly occurred in anaerobic stage (ANS). Fed with synthetic and real wastewater for 120days at 1.5h HRT, SIBPD demonstrated good removal performance showing 87.14% for COD, 92.84% for NH4(+)-N and 82.58% for TP along with 80.72% of nitrate removed by ANS. TN removal efficiency was 83.74% when conducting real wastewater. Compared with sulfur-based process, the effluent pH of SIBPD was maintained at 6.99-7.34 and the highest SO4(2-) concentration was only 64.63mgL(-1). This study revealed a promising and feasible application prospect for on-site domestic wastewater treatment. PMID:25827248

  14. Semi-nitritation process producing optimum influent for anammox process in treatment of domestic wastewater.

    PubMed

    Tang, Xiaoxue; Yang, Qing; Li, Jianlin; Peng, Yongzhen; Xu, Zhubing; He, Jianzhong

    2016-06-01

    The process of anaerobic ammonium oxidation (Anammox) requires a proper ratio of NH4(+)-N and NO2(-)-N in the influent, which is difficult to control upon treating domestic wastewater. In this study, a control strategy of semi-nitritation (SN) process based on monitoring the pH profile and NH4(+)-N concentration in a sequencing batch reactor (SBR) was developed. The aeration time of each cycle in SN-SBR was calculated using the established equation tSN=tCOD+0.56αnS0/(S0-Sn). To verify the suitability of the control strategy, SN-SBR was operated continuously for 20 cycles, fed with real domestic wastewater with a fluctuating COD of 200-400 mg L(-1) and NH4(+)-N of 65-80 mg L(-1). The nitrogen removal performance of SN-anammox system using the developed control strategy was also monitored. Results showed that SN-SBR was able to generate a suitable ratio of NH4(+)-N to NO2(-)-N for the following anammox process, the TN removal rate of the SN-anammox system achieved 91.7 ± 0.4% and the average ammonium, nitrite and nitrate concentration of effluent was only 0.50 ± 0.24, 0.13 ± 0.09 and 4.9 ± 0.22 mg L(-1), respectively. This study has potential application in the treatment of domestic wastewater using combined SN-anammox process. PMID:26963236

  15. Wastewater treatment by a modular, domestic-scale reedbed system for safe horticultural irrigation.

    PubMed

    Derry, Chris; Maheshwari, Basant

    2015-12-15

    The aim of the study was to assess the sequential treatment performance of a commercial, domestic-scale modular reedbed system intended to provide safe horticultural irrigation water. Previously only mechanical treatment systems involving forced aeration with subsequent disinfection, usually by tablet-chlorination, had been accredited in Australia. The modular design of the hybrid, subsurface-flow reedbed system offered 5 control points where monitoring and management of the treatment train could be carried out. Ten chemical parameters (chemical and biochemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, total nitrogen, dissolved oxygen percentage saturation and suspended solids) and 4 microbial parameters (total coliform, Escherichia coli, enterococci and Clostridium perfringens) reached satisfactory levels as a result of the treatment process. Health requirements for safe horticultural irrigation were met by the outlet of the second reedbed, providing a high level of treatment-backup capacity in terms of the remaining 2 reedbeds. This suggested that chlorination was a redundant backup precaution in treating irrigation water to the acceptable regional guideline level for all horticultural uses, including the spray irrigation of salad crops eaten raw. PMID:26282758

  16. [Preparation of a composite coagulant from fly ash and its application in domestic wastewater treatment].

    PubMed

    Li, Ya-Qiang; Hu, Kai; Zhao, Qing-Liang; Tang, Feng; Liu, Zhi-Gang; Cui, Fu-Yi

    2007-11-01

    Fly ash was investigated as a raw material for the preparation of a composite coagulant with sulfuric acid. Types of acid solution, H2SO4 concentration, ratio of H2SO4 to fly ash and stirring time were respectively examined as factors that influenced the efficiency of converting the iron and aluminum components into a composite coagulant and coagulation performance on domestic wastewater. The coagulant was attained at the condition of H2SO4-fly ash ratio of 5 mL/g, H2SO4 of 2 mol/L, stirring time of 4h and stabling time of 30 min, and contained Fe3+ of 0.010 8 mol/L with conversion efficiency of 11.4% and Al3+ of 0.035 4 mol/L with conversion efficiency of 4.3%. Removal efficiencies of COD and SS by this type of coagulant reached 70.4% and 91.9% respectively when treating domestic wastewater. This study provides a promising means to utilize fly ash for coagulation, which possibly makes wastewater treatment more economical and more sustainable. PMID:18290474

  17. Assessing the potentials of Lemna minor in the treatment of domestic wastewater at pilot scale.

    PubMed

    Priya, Anima; Avishek, Kirti; Pathak, Gopal

    2012-07-01

    Water crisis is one of the most serious problems faced by the world today. Phytoremediation is one of the serious efforts towards sustainability. Macrophyte-based wastewater treatment systems have several potential advantages compared with conventional treatment systems. Duckweeds (Lemna spp., Spirodela spp., Wolffia spp.) are small, green freshwater, free-floating aquatic plants. The primary objective of this work was to analyze the role of duckweeds in organic waste and nutrient removal from domestic wastewater being generated from hostels of Birla Institute of Technology, Mesra, Ranchi (India). Interesting results were obtained in which the BOD value reduced by 94.45% and the level of orthophosphate at the end of the work was found to be reduced by 79.39%. The duckweeds flourished well during the experimental period in the pH range of 7 to 8; it can be said that, other factors remaining favorable, the optimum pH for duckweed growth ranges from 7 to 8. Therefore, it can be concluded that this treatment can be successfully carried out on a large scale. Also, it is a low-cost solution to wastewater treatment problems and could satisfy the discharge standards. PMID:21823047

  18. Scaling-up of membraneless microbial electrolysis cells (MECs) for domestic wastewater treatment: Bottlenecks and limitations.

    PubMed

    Escapa, A; San-Martín, M I; Mateos, R; Morán, A

    2015-03-01

    Microbial electrolysis cells (MECs) have the potential to become a sustainable domestic wastewater (dWW) treatment system. However, new scale-up experiences are required to gain knowledge of critical issues in MEC designs. In this study we assess the ability of two twin membraneless MEC units (that are part of a modular pilot-scale MEC) to treat dWW. Batch tests yielded COD removal efficiencies as high as 92%, with most of the hydrogen (>80% of the total production) being produced during the first 48h. During the continuous tests, MECs performance deteriorated significantly (energy consumption was relatively high and COD removal efficiencies fell below 10% in many cases), which was attributed to an inadequate configuration of the anodic chamber, insufficient mixing inside this chamber, inefficient hydrogen management on the cathode side and finally to dWW in itself. Some alternatives to the current design are suggested. PMID:25590425

  19. Domestic wastewater treatment using multi-electrode continuous flow MFCs with a separator electrode assembly design.

    PubMed

    Ahn, Yongtae; Logan, Bruce E

    2013-01-01

    Treatment of domestic wastewater using microbial fuel cells (MFCs) will require reactors with multiple electrodes, but this presents unique challenges under continuous flow conditions due to large changes in the chemical oxygen demand (COD) concentration within the reactor. Domestic wastewater treatment was examined using a single-chamber MFC (130 mL) with multiple graphite fiber brush anodes wired together and a single air cathode (cathode specific area of 27 m(2)/m(3)). In fed-batch operation, where the COD concentration was spatially uniform in the reactor but changed over time, the maximum current density was 148 ± 8 mA/m(2) (1,000 Ω), the maximum power density was 120 mW/m(2), and the overall COD removal was >90 %. However, in continuous flow operation (8 h hydraulic retention time, HRT), there was a 57 % change in the COD concentration across the reactor (influent versus effluent) and the current density was only 20 ± 13 mA/m(2). Two approaches were used to increase performance under continuous flow conditions. First, the anodes were separately wired to the cathode, which increased the current density to 55 ± 15 mA/m(2). Second, two MFCs were hydraulically connected in series (each with half the original HRT) to avoid large changes in COD among the anodes in the same reactor. The second approach improved current density to 73 ± 13 mA/m(2). These results show that current generation from wastewaters in MFCs with multiple anodes, under continuous flow conditions, can be improved using multiple reactors in series, as this minimizes changes in COD in each reactor. PMID:23053104

  20. Dynamics and functions of bacterial communities in bark, charcoal and sand filters treating greywater.

    PubMed

    Dalahmeh, Sahar S; Jönsson, Håkan; Hylander, Lars D; Hui, Nan; Yu, Dan; Pell, Mikael

    2014-05-01

    This study explored the effects of greywater application on the dynamics and functions of biofilms developed in bark, activated charcoal and sand filters used for removal of organic matter and nitrogen. Duplicate columns (20 cm diameter, 60 cm deep) were packed with bark, charcoal or sand with effective size 1.4 mm and uniformity coefficient 2.2, and dosed with 32 L m(-2) day(-1) of an artificial greywater (14 g BOD5 m(-2) day(-1)) for 116 days. Potential respiration rate (PRR), determined in filter samples after addition of excess glucose, and bacterial diversity and composition, analysed by 454-pyrosequencing of bacterial 16S ribosomal DNA, were measured at different times and depths in the filters. The bark and charcoal filters were more efficient in removing BOD5 than the sand (98, 97% and 75%, respectively). The highest PRR in the 0-2 cm layer of the columns on day 84 was found in the bark filters, followed by the charcoal and sand filters (632 ± 66, 222 ± 34 and 56 ± 2 mg O2 L(-1), respectively; n = 2). Bacterial community in the bark filters showed the highest richness. The charcoal and sand filters both developed more diverse and dynamic (changing over time and depth) bacterial communities than the bark. In addition to the greywater, the lignocelluosic composition of the bark and its lower pH probably selected for the bacterial community structure and the organic content provided additional substrate, as shown by its higher PRR and its different nitrifying bacterial genera. In the oligotrophic charcoal and sand, the composition of the greywater itself defined the bacterial community. Thus, the initially low bacterial biomass in the latter filters was enriched over time, allowing a diversified bacterial community to develop. The top layers of the bark and charcoal filters displayed a high dominance of Rhizobium, Pseudomonas and Acinetobacter, which were less evident in the 60 cm layer, whereas in the sand filters these genera were

  1. Cell-to-cell pollution reduction effectiveness of subsurface domestic treatment wetlands.

    PubMed

    Steer, David N; Fraser, Lauchlan H; Seibert, Beth A

    2005-05-01

    Quarterly water quality data from 1998 to 2003 for eight single-family domestic systems serving 2-7 people in Ohio, USA, were studied to determine the cell-to-cell and system wide pathogen reduction efficiency and effectiveness of these systems in meeting compliance standards. Two-cell domestic wastewater treatment systems displayed significant variability in their cell-to-cell performance that directly impacted the overall ability of systems to meet effluent compliance standards. Fecal coliform was effectively reduced (approximately 99%) in these systems while two-thirds of the input biochemical oxygen demand was mitigated in each of the cells of these systems. Fecal coliform and biochemical oxygen demand were typically reduced below 2000 counts per 100 ml and 15 mg/l (respectively) before discharge to surface waters. Total suspended solids were reduced by approximately 80% overall with cell one retaining the majority of the solids (approximately 70%). These systems discharged more than 18 mg/l of suspended solids in less than 5% of the samples thus displaying a very high compliance rate. Ammonia and total phosphorus were less effectively treated (approximately 30-40% reductions in each cell) and exceeded standards (1.5 mg/l) more frequently. Analyses based on the number of occupants indicated that the two-cell design used here was most effective for smaller occupancy systems. More study is required to determine the value of this design for large occupancy systems. In the future, wetlands should be evaluated based on the total loads delivered to the watershed rather than by effluent concentrations. PMID:15627569

  2. Two-stage anaerobic fluidized-bed membrane bioreactor treatment of settled domestic wastewater.

    PubMed

    Bae, J; Yoo, R; Lee, E; McCarty, P L

    2013-01-01

    A two-stage anaerobic fluidized-bed membrane bioreactor (SAF-MBR) system was applied for the treatment of primary-settled domestic wastewater that was further pre-treated by either 10 μm filtration or 1 mm screening. While the different pre-treatment options resulted in different influent qualities, the effluent qualities were quite similar. In both cases at a total hydraulic retention time of 2.3 h and 25 °C, chemical oxygen demand and biochemical oxygen demand (BOD5) removals were 84-91% and 92-94%, with effluent concentrations lower than 25 and 7 mg/L, respectively. With a membrane flux of 6-12 L/m(2)/h, trans-membrane pressure remained below 0.2 bar during 310 d of continuous operation without need for membrane chemical cleaning or backwashing. Biosolids production was estimated to be 0.028-0.049 g volatile suspended solids/g BOD5, which is far less than that with comparable aerobic processes. Electrical energy production from combined heat and power utilization of the total methane produced (gaseous and dissolved) was estimated to be more than sufficient for total system operation. PMID:23863433

  3. Effect of temperature on the treatment of domestic wastewater with a staged anaerobic fluidized membrane bioreactor.

    PubMed

    Yoo, R H; Kim, J H; McCarty, P L; Bae, J H

    2014-01-01

    A laboratory staged anaerobic fluidized membrane bioreactor (SAF-MBR) system was applied to the treatment of primary clarifier effluent from a domestic wastewater treatment plant with temperature decreasing from 25 to 10 °C. At all temperatures and with a total hydraulic retention time of 2.3 h, overall chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) removals were 89% and 94% or higher, with permeate COD and BOD5 of 30 and 7 mg/L or lower, respectively. No noticeable negative effects of low temperature on organic removal were found, although a slight increase to 3 mg/L in volatile fatty acids concentrations in the effluent was observed. Biosolids production was 0.01-0.03 kg volatile suspended solids/kg COD, which is far less than that with aerobic processes. Although the rate of trans-membrane pressure at the membrane flux of 9 L/m(2)/h increased as temperature decreased, the SAF-MBR was operated for longer than 200 d before chemical cleaning was needed. Electrical energy potential from combustion of the total methane production (gaseous and dissolved) was more than that required for system operation. PMID:24647177

  4. Concentrations and fate of sugars, proteins and lipids during domestic and agro-industrial aerobic treatment.

    PubMed

    Gorini, Dominique; Choubert, Jean-Marc; le Pimpec, Paul; Heduit, Alain

    2011-01-01

    This work investigates the composition and the fate of sugars, lipids, proteins, amino acids under aerobic conditions for 13 domestic and 4 agro-industrial wastewaters, sampled before and after treatment. The rates of aerobic degradation were moreover studied with a 21-day continuous aeration batch test. It is shown that the sum of the biochemical forms represented 50 to 85% of the total chemical oxygen demand (COD). Lipids represented the half of the identified COD; sugars and proteins correspond to a quarter of the identified COD. Aerobic processes provided an increase of the relative fractions for proteins, whereas the ones of lipids decreased and sugars fraction remains stable. For the wastewaters released from cheese dairy (lipid-rich) and slaughterhouses (protein/lipid-rich), the dissolved phase after biological treatment is composed of proteins whereas the particulate one is composed of lipids. After the 21-day test, the concentration in proteins was nearby 10 mg/L. The results should be used for operations of WWTP to detect when a dysfunction is about to occur. They can be used to predict the concentrations in the treated water when upgrading an existing municipal plant that will admit agro-industrial discharge. PMID:21866767

  5. Treatment of domestic wastewater by subsurface flow constructed wetlands filled with gravel and tire chip media.

    PubMed

    Richter, A Y; Weaver, R W

    2003-12-01

    Subsurface flow constructed wetlands (SFCWs) are becoming increasingly common in on-site treatment of wastewater. Gravel is the most popular form of wetland fill medium, but tire chips provide more porosity, are less dense, and less expensive. This study determines the treatment efficiency of SFCWs filled with gravel or tire chip media to treat domestic wastewater. The influent and effluent of six SFCWs filled with tire chip medium and six SFCWs filled with gravel were monitored for 5 to 16 consecutive months. Parameters measured included pH, biochemical oxygen demand (BOD5), total and volatile suspended solids, NH4, P, and fecal and total coliforms. The only clear difference between medium types in wetland performance was for P. Soluble P in the effluent averaged 1.6 +/- 1.0 mg l(-1) in the tire chip-filled wetlands and 4.8 +/- 3.2 mg l(-1) in the gravel-filled wetlands. Most likely, Fe from exposed wires in shredded steel-belted tires complexed with P to create an insoluble compound. Tire chips may be a better fill medium for SFCWs than gravel because of higher porosity, lower cost, and greater reduction of P in effluent. PMID:14977152

  6. Treatment of domestic wastewater by vertical flow constructed wetland planted with umbrella sedge and Vetiver grass.

    PubMed

    Kantawanichkul, Suwasa; Sattayapanich, Somsiri; van Dien, Frank

    2013-01-01

    The aim of this study was to investigate the efficiency of wastewater treatment by vertical flow constructed wetland systems under different hydraulic loading rates (HLR). The comparison of two types of plants, Cyperus alternifolius (Umbrella sedge) and Vetiveria zizanioides (Vetiver grass), was also conducted. In this study, six circular concrete tanks (diameter 0.8 m) were filled with fine sand and gravel to the depth of 1.23 m. Three tanks were planted with Umbrella sedge and the other three tanks were planted with Vetiver grass. Settled domestic wastewater from Chiang Mai University (chemical oxygen demand (COD), NH4(+)-N and suspended solids (SS) of 127.1, 27.4 and 29.5 mg/L on average, respectively) was intermittently applied for 45 min and rested for 3 h 15 min. The HLR of each tank was controlled at 20, 29 and 40 cm/d. It was found that the removal efficiency of the Umbrella sedge systems was higher than the Vetiver grass systems for every parameter, and the lowest HLR provided the maximum treatment efficiency. The removal efficiency of COD and nitrogen in terms of total Kjeldahl nitrogen (TKN) was 76 and 65% at 20 cm/d HLR for Umbrella sedge compared to only 67 and 56% for Vetiver grass. Nitrogen accumulation in plant biomass was also higher in Umbrella sedge than in Vetiver grass in every HLR. Umbrella sedge was thus proved to be a suitable constructed wetland plant in tropical climates. PMID:24056433

  7. Domestic sewage treatment in a pilot system composed of UASB and SBR reactors.

    PubMed

    Torres, P; Foresti, E

    2001-01-01

    The results obtained from the operation of a treatment system composed of an anaerobic (up-flow sludge blanket-UASB) reactor followed by an aerobic (sequencing batch-SBR) reactor treating domestic sewage are presented and discussed. The pilot plant was monitored during 6 months, aiming to obtain performance data on organic matter, nitrogen and phosphate removal under different operating conditions. The UASB reactor was operated at a constant hydraulic detention time (0) of 6 h while the SBR performance was monitored in four different duration cycles (24, 12, 6 and 4 h) corresponding to aeration times (AT) of 22, 10, 4 and 2 h, respectively. COD and TSS overall removal efficiencies (Eo) up to 91% and 84%, respectively, were achieved independently on the aeration time applied to the SBR. In respect to nitrification and phosphate removal, AT was found to be a determining operating parameter. TKN removal of approximately 90% was achieved for AT equal to or higher than 10 h; complete nitrification occurred for AT higher than 4 h; significant phosphate removal (72%) occurred only at the AT of 2 h. It was not possible to achieve simultaneous efficient removal of nitrogen and phosphate, under the operating conditions imposed on the treatment system. PMID:11575090

  8. A novel eductor-based MBR for the treatment of domestic wastewater.

    PubMed

    Mitra, Shibam; Daltrophe, Naphtali Claude; Gilron, Jack

    2016-09-01

    A novel aeration device has been developed that combines the mechanism of a venturi aerator with the flow multiplier effect of an eductor used for pump driven mixing. The performance of this novel eductor was evaluated in a flat-sheet immersed MBR and compared with the same MBR equipped with a conventional diffuser for the treatment of domestic wastewater. The eductor showed a higher rate of oxygen transfer both in clean and wastewater compared to the diffuser. The α value with the eductor (0.91) was also found to be more than that of the diffuser (0.75). Higher recirculation rate through the eductor resulted in a higher mixing/turbulance inside the MBR tank and thus alleviated membrane fouling significantly compared to the diffuser. The performance of the MBR in terms of organics removal was also found to be higher with the eductor than the diffuser. The eductor could have significant potential as a combined aerator and mixer in the field of wastewater treatment by MBR. PMID:27179340

  9. Seeking a way to promote the use of constructed wetlands for domestic wastewater treatment in developing countries.

    PubMed

    Zurita, F; Belmont, M A; De Anda, J; White, J R

    2011-01-01

    The aim of this study was to evaluate the domestic wastewater treatment efficiency as well as the survivability of commercially valuable ornamental plants in subsurface flow wetlands (SSFW) for domestic wastewater (DWW) treatment in laboratory and pilot wetland studies. The laboratory scale study included five different species (Zantedeschia aethiopica, Strelitzia reginae, Anthurium andreanum, Canna hybrids and Hemmerocallis dumortieri) that were evaluated in horizontal flow subsurface treatment cells. All the plants survived during the 6-month experimental period demonstrating high wetland nutrient treatment efficiency. In order to validate and expand these preliminary results, a pilot-scale wetland study was carried out in SSFWs under two different flow regimes (horizontal and vertical flow). Four ornamental species were tested during a 1-year period: Zantedeschia aethiopica, Strelitzia reginae, Anthurium andreanum and Agapanthus africanus. The removal efficiencies were significantly higher in the vertical subsurface-flow constructed wetlands (VFCW) for all pollutants, except for nitrate (NO(3)-N), total nitrogen (TN) and total suspended solids (TSS). These results show that it is feasible to use select non-wetland plants with high market value in SSFWs without reducing the efficiency of the wastewater treatment system, although future work should continue in order to apply this technology in a large scale. The added value of floriculture in treatment wetlands can help to promote the use of constructed wetlands (CW) for domestic wastewater treatment in developing countries where economical resources are scarce and water pollution with DWW is common. PMID:21330710

  10. Filamentous fungi in Indah Water Konsortium (IWK) sewage treatment plant for biological treatment of domestic wastewater sludge.

    PubMed

    Fakhrul-Razi, A; Alam, M Zahangir; Idris, Azni; Abd-Aziz, Suraini; Molla, Abul H

    2002-03-01

    A study was carried out to isolate and identify filamentous fungi for the treatment of domestic wastewater sludge by enhancing biodegradability, settleability and dewaterability of treated sludge using liquid state bioconversion process. A total of 70 strains of filamentous fungi were isolated from three different sources (wastewater, sewage sludge and leachate) of IWK's (Indah Water Konsortium) sewage treatment plant, Malaysia. The isolated strains were purified by conventional techniques and identified by microscopic examination. The strains isolated belonged to the genera of Penicillium, Aspergillus, Trichoderma, Spicaria and Hyaloflorae The distribution of observed isolated fungi were 41% in sewage sludge followed by 39% in wastewater and 20% in leachate. The predominant fungus was Penicillium (39 strains). The second and third most common isolates were Aspergillus (14 strains) and Trichoderma (12 strains). The other isolates were Spicaria (3 strains) and Hyaloflorae (2 strains). Three strains (WWZP1003, LZP3001, LZP3005) of Penicillium (P. corylophilum, P. waksmanii, and P. citrinum respectively), 2 strains (WWZA1006 and SS2017) of Aspergillus (A. terrues and A. flavus respectively) and one strain (SSZT2008) of Trichoderma (T. harzianum) were tentatively identified up to species level and finally verified by CABI Bioscience Identification Services, UK. PMID:11929070

  11. Combining activated carbon adsorption with heterogeneous photocatalytic oxidation: lack of synergy for biologically treated greywater and tetraethylene glycol dimethyl ether.

    PubMed

    Gulyas, Holger; Argáez, Angel Santiago Oria; Kong, Fanzhuo; Jorge, Carlos Liriano; Eggers, Susanne; Otterpohl, Ralf

    2013-01-01

    The aim of the study was to evaluate whether the addition of activated carbon in the photocatalytic oxidation of biologically pretreated greywater and of a polar aliphatic compound gives synergy, as previously demonstrated with phenol. Photocatalytic oxidation kinetics were recorded with fivefold concentrated biologically pretreated greywater and with aqueous tetraethylene glycol dimethyl ether solutions using a UV lamp and the photocatalyst TiO2 P25 in the presence and the absence of powdered activated carbon. The synergy factor, SF, was quantified as the ratio of photocatalytic oxidation rate constant in the presence of powdered activated carbon to the rate constant without activated carbon. No synergy was observed for the greywater concentrate (SF approximately 1). For the aliphatic compound, tetraethylene glycol dimethyl ether, addition of activated carbon actually had an inhibiting effect on photocatalysis (SF < 1), while synergy was confirmed in reference experiments using aqueous phenol solutions. The absence of synergy for the greywater concentrate can be explained by low adsorbability of its organic constituents by activated carbon. Inhibition of the photocatalytic oxidation of tetraethylene glycol dimethyl ether by addition of powdered activated carbon was attributed to shading of the photocatalyst by the activated carbon particles. It was assumed that synergy in the hybrid process was limited to aromatic organics. Regardless of the lack of synergy in the case of biologically pretreated greywater, the addition of powdered activated carbon is advantageous since, due to additional adsorptive removal of organics, photocatalytic oxidation resulted in a 60% lower organic concentration when activated carbon was present after the same UV irradiation time. PMID:24191472

  12. Combining activated carbon adsorption with heterogeneous photocatalytic oxidation: Lack of synergy for biologically treated greywater and tetraethylene glycol dimethyl ether

    PubMed Central

    Gulyas, Holger; Argáez, Ángel Santiago Oria; Kong, Fanzhuo; Jorge, Carlos Liriano; Eggers, Susanne; Otterpohl, Ralf

    2013-01-01

    The aim of the study was to evaluate whether the addition of activated carbon in the photocatalytic oxidation of biologically pretreated greywater and of a polar aliphatic compound gives synergy, as previously demonstrated with phenol. Photocatalytic oxidation kinetics were recorded with fivefold concentrated biologically pretreated greywater and with aqueous tetraethylene glycol dimethyl ether solutions using a UV lamp and the photocatalyst TiO2 P25 in the presence and the absence of powdered activated carbon. The synergy factor, SF, was quantified as the ratio of photocatalytic oxidation rate constant in the presence of powdered activated carbon to the rate constant without activated carbon. No synergy was observed for the greywater concentrate (SF ≈ 1). For the aliphatic compound, tetraethylene glycol dimethyl ether, addition of activated carbon actually had an inhibiting effect on photocatalysis (SF < 1), while synergy was confirmed in reference experiments using aqueous phenol solutions. The absence of synergy for the greywater concentrate can be explained by low adsorbability of its organic constituents by activated carbon. Inhibition of the photocatalytic oxidation of tetraethylene glycol dimethyl ether by addition of powdered activated carbon was attributed to shading of the photocatalyst by the activated carbon particles. It was assumed that synergy in the hybrid process was limited to aromatic organics. Regardless of the lack of synergy in the case of biologically pretreated greywater, the addition of powdered activated carbon is advantageous since, due to additional adsorptive removal of organics, photocatalytic oxidation resulted in a 60% lower organic concentration when activated carbon was present after the same UV irradiation time. PMID:24191472

  13. Use of GIS in siting stabilization pond facilities for domestic wastewater treatment.

    PubMed

    Gemitzi, Alexandra; Tsihrintzis, Vassilios A; Christou, Odysseas; Petalas, Christos

    2007-01-01

    Geographic information systems (GIS) use is presented in the problem of sitting areas for construction of natural systems such as stabilization ponds (SPs) for domestic wastewater treatment. For this purpose, several variables, such as topography, land use, type of geological formation, distance to major rivers or lakes, distance to existing cities and villages, existence of environmentally protected areas, mean minimum monthly temperatures and required wastewater effluent characteristics were analyzed with the GIS, in order to accept or reject a particular area within a region. The method is applied in the region of Thrace (Northeast Greece) at the municipal level. The required area for SP systems was calculated in each of the 36 municipalities of Thrace (including two islands, Thassos and Samothraki) as a function of the population of each municipality, temperature and local wastewater effluent discharge criteria. Based on the GIS analysis, suitable locations were identified in each municipality first, and then the total required surface area of these systems was compared to the available surface area of each municipality, in order to decide whether SP systems could be a viable solution to the wastewater management problem in the particular region. In that way the present methodology offers a fast and simple method to check the suitability of new areas for construction of such systems. PMID:16564613

  14. Ammonia oxidizers in a pilot-scale multilayer rapid infiltration system for domestic wastewater treatment.

    PubMed

    Lian, Yingli; Xu, Meiying; Zhong, Yuming; Yang, Yongqiang; Chen, Fanrong; Guo, Jun

    2014-01-01

    A pilot-scale multilayer rapid infiltration system (MRIS) for domestic wastewater treatment was established and efficient removal of ammonia and chemical oxygen demand (COD) was achieved in this study. The microbial community composition and abundance of ammonia oxidizers were investigated. Efficient biofilms of ammonia oxidizers in the stationary phase (packing material) was formed successfully in the MRIS without special inoculation. DGGE and phylogenetic analyses revealed that proteobacteria dominated in the MRIS. Relative abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) showed contrary tendency. In the flowing phase (water effluent), AOA diversity was significantly correlated with the concentration of dissolve oxygen (DO), NO3-N and NH3-N. AOB abundance was significantly correlated with the concentration of DO and chemical oxygen demand (COD). NH3-N and COD were identified as the key factors to shape AOB community structure, while no variable significantly correlated with that of AOA. AOA might play an important role in the MRIS. This study could reveal key environmental factors affecting the community composition and abundance of ammonia oxidizers in the MRIS. PMID:25479611

  15. Ammonia Oxidizers in a Pilot-Scale Multilayer Rapid Infiltration System for Domestic Wastewater Treatment

    PubMed Central

    Lian, Yingli; Xu, Meiying; Zhong, Yuming; Yang, Yongqiang; Chen, Fanrong; Guo, Jun

    2014-01-01

    A pilot-scale multilayer rapid infiltration system (MRIS) for domestic wastewater treatment was established and efficient removal of ammonia and chemical oxygen demand (COD) was achieved in this study. The microbial community composition and abundance of ammonia oxidizers were investigated. Efficient biofilms of ammonia oxidizers in the stationary phase (packing material) was formed successfully in the MRIS without special inoculation. DGGE and phylogenetic analyses revealed that proteobacteria dominated in the MRIS. Relative abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) showed contrary tendency. In the flowing phase (water effluent), AOA diversity was significantly correlated with the concentration of dissolve oxygen (DO), NO3-N and NH3-N. AOB abundance was significantly correlated with the concentration of DO and chemical oxygen demand (COD). NH3-N and COD were identified as the key factors to shape AOB community structure, while no variable significantly correlated with that of AOA. AOA might play an important role in the MRIS. This study could reveal key environmental factors affecting the community composition and abundance of ammonia oxidizers in the MRIS. PMID:25479611

  16. Co-treatment of landfill leachate and domestic wastewater using a submerged aerobic biofilter.

    PubMed

    Ferraz, F M; Povinelli, J; Pozzi, E; Vieira, E M; Trofino, J C

    2014-08-01

    This study used a pilot-scale submerged aerobic biofilter (SAB) to evaluate the co-treatment of domestic wastewater and landfill leachate that was pre-treated by air stripping. The leachate tested volumetric ratios were 0, 2, and 5%. At a hydraulic retention time of 24 h, the SAB was best operated with a volumetric ratio of 2% and removed 98% of the biochemical oxygen demand (BOD), 80% of the chemical oxygen demand (COD) and dissolved organic carbon (DOC), and 90% of the total suspended solids (TSS). A proposed method, which we called the "equivalent in humic acid" (Eq.HA) approach, indicated that the hardly biodegradable organic matter in leachate was removed by partial degradation (71% of DOC Eq.HA removal). Adding leachate at a volumetric ratio of 5%, the concentration of the hardly biodegradable organic matter was decreased primarily as a result of dilution rather than biodegradation, which was confirmed by Fourier transform infrared (FTIR) spectroscopy. The total ammoniacal nitrogen (TAN) was mostly removed (90%) by nitrification, and the SAB performances at the volumetric ratios of 0 and 2% were equal. For the three tested volumetric ratios of leachate (0, 2, and 5%), the concentrations of heavy metals in the treated samples were below the local limits. PMID:24762568

  17. Net energy production and emissions mitigation of domestic wastewater treatment system: a comparison of different biogas-sludge use alternatives.

    PubMed

    Chen, Shaoqing; Chen, Bin

    2013-09-01

    Wastewater treatment systems are increasingly designed for the recovery of valuable chemicals and energy in addition to waste stream disposal. Herein, the life-cycle energy production and emissions mitigation of a typical domestic wastewater treatment system were assessed, in which different combinations of biogas use and sludge processing lines for industrial or household applications were considered. The results suggested that the reuse of biogas and sludge was so important in the system's overall energy balance and environmental performance that it may offset the cost in the plant's installation and operation. Combined heat and power and household utilization were two prior options for net energy production, provided an ideal power conversion efficiency and biogas production. The joint application of household biogas use and sludge nutrient processing achieved both high net energy production and significant environmental remediation across all impact categories, representing the optimal tradeoff for domestic wastewater treatment. PMID:23880131

  18. Treatment of Concurrent Substance Dependence, Child Neglect and Domestic Violence: A Single Case Examination Involving Family Behavior Therapy

    PubMed Central

    Romero, Valerie; Allen, Daniel N.

    2012-01-01

    Although child neglect and substance abuse co-occur in greater than 60% of child protective service cases, intervention outcome studies are deplorably lacking. Therefore, a home-based Family Behavior Therapy is described in the treatment of a woman evidencing child neglect, substance dependence, domestic violence and other co-occurring problems. Treatment included contingency management, self control, stimulus control, communication and child management skills training exercises, and financial management components. Results indicated improvements in child abuse potential, home hazards, domestic violence, and drug use, which were substantiated by objective urinalysis testing, and tours of her home. Validity checks indicated the participant was being truthful in her responses to standardized questionnaires, and assessors were “blind” to study intent. Limitations (i.e., lack of experimental control and follow-up data collection) of this case example are discussed in light of these results. PMID:23226920

  19. Domestic wastewater treatment by a submerged MBR (membrane bio-reactor) with enhanced air sparging.

    PubMed

    Chang, I S; Judd, S J

    2003-01-01

    The air sparging technique has been recognised as an effective way to control membrane fouling. However, its application to a submerged MBR (Membrane Bio-Reactor) has not yet been reported. This paper deals with the performances of air sparging on a submerged MBR for wastewater treatment. Two kinds of air sparging techniques were used respectively. First, air is injected into the membrane tube channels so that mixed liquor can circulate in the bioreactor (air-lift mode). Second, a periodic air-jet into the membrane tube is introduced (air-jet mode). Their applicability was evaluated with a series of lab-scale experiments using domestic wastewater. The flux increased from 23 to 33 l m(-2) h(-1) (43% enhancement) when air was injected for the air-lift module. But further increase of flux was not observed as the gas flow increased. The Rc/(Rc+Rf), ratio of cake resistance (Rc) to sum of Rc and Rf (internal fouling resistance), was 23%, indicating that the Rc is not the predominant resistance unlike other MBR studies. It showed that the cake layer was removed sufficiently due to the air injection. Thus, an increase of airflow could not affect the flux performance. The air-jet module suffered from a clogging problem with accumulated sludge inside the lumen. Because the air-jet module has characteristics of dead end filtration, a periodic air-jet was not enough to blast all the accumulated sludge out. But flux was greater than in the air-lift module if the clogging was prevented by an appropriate cleaning regime such as periodical backwashing. PMID:12926682

  20. Impact of electrode configurations on retention time and domestic wastewater treatment efficiency using microbial fuel cells.

    PubMed

    Kim, Kyoung-Yeol; Yang, Wulin; Logan, Bruce E

    2015-09-01

    Efficient treatment of domestic wastewater under continuous flow conditions using microbial fuel cells (MFCs) requires hydraulic retention times (HRTs) that are similar to or less than those of conventional methods such as activated sludge. Two MFCs in series were compared at theoretical HRTs of 8.8, 4.4 and 2.2 h using two different brush-electrode MFC configurations: a full brush evenly spaced between two cathodes (S2C); and trimmed brush anodes near a single cathode (N1C). The MFCs with two cathodes produced more power than the MFCs with a single cathode, with 1.72 mW for the S2C, compared to and 1.12 mW for the N1C at a set HRT = 4.4 h. The single cathode MFCs with less cathode area removed slightly more COD (54.2 ± 2.3%, N1C) than the two-cathode MFCs (48.3 ± 1.0%, S2C). However, the higher COD removal was due to the longer HRTs measured for the MFCs with the N1C configuration (10.7, 5.3 and 3.1 h) than with the S2C configuration (7.2, 3.7 and 2.2 h), despite the same theoretical HRT. The longer HRTs of the N1C MFCs also resulted in slightly higher coulombic efficiencies (≤37%) than those of the S2C MFCs (≤29%). While the S2C MFC configuration would be more advantageous based on electrical power production, the N1C MFC might be more useful on the basis of capital costs relative to COD removal efficiency due to the use of less cathode surface area per volume of reactor. PMID:25996751

  1. Public awareness, behaviours and attitudes towards domestic wastewater treatment systems in the Republic of Ireland

    NASA Astrophysics Data System (ADS)

    Naughton, O.; Hynds, P. D.

    2014-10-01

    Numerous studies have highlighted and quantified the role of domestic wastewater treatment systems (DWWTSs) as significant sources of human-specific aquatic contaminants in both developed and developing regions, particularly with respect to private and municipal groundwater supplies. However, from a socio-hydrological perspective, little work has focused on these systems and the potential environmental and human burden posed. This is of particular relevance in the Republic of Ireland, where approximately one third of the population is serviced by DWWTSs. The objective of the current study was to examine levels of awareness and subsequent behavioural tendencies among owners and users of DWWTSs in the Republic of Ireland, particularly in light of recent and future (national and EU) legislative amendments. Structured questionnaires were completed bi-modally with 1106 Irish respondents. Analysis identified a number of significant knowledge gaps which currently exist among DWWTS users in Ireland. These were associated with environmentally inadvisable behavioural practises, potentially leading to increased contamination vulnerability and subsequently, increased human exposure to waterborne contaminants. Household water supply type was significantly associated with DWWTS threat acknowledgement (p = 0.014), with unregulated private groundwater users exhibited the lowest awareness of DWWTS as a potential source of aquatic contaminants despite being the group at greatest risk. A bi-modal clustering approach was employed, with respondents found to fall into one of three distinct “attitudinal” clusters. Future engagement strategies should strive to provide guidance regarding the role of people and their activities within the hydrological cycle. The current study reinforces this conclusion, while providing evidence-based recommendations regarding provision of demographically focused educational strategies; these will further increase environmental policy compliance, and in

  2. Estimates of global greenhouse gas emissions from industrial and domestic wastewater treatment. Final report, September 1994-March 1997

    SciTech Connect

    Doorn, M.R.J.; Strait, R.P.; Barnard, W.R.; Eklund, B.

    1997-09-01

    The report summarizes the findings of field tests and provides emission factors for methane (CH4) and nitorus oxide (N2O) from wastewater treatment (WWT). It also includes country-specific activity data on industrial and domestic WWT which were used to develop country-specific emission estimates for CH4 and N2O. The report concludes that WWT is unlikely to be a significant source of volatile organic carbon and carbon dioxide emissions. The biggest contributor to industrial CH4 emissions from WWT is the pulp and paper industry in developing and Eastern European countries. The second principal contributor to CH4 emissions from WWT is the meat and poultry industry. Russia is believed to be the largest contributor. CH4 emissions from untreated domestic wastewater may be many times higher than those of treated wastewater. The report provides rough estimates for global N2O emissions from WWT.

  3. Health Effects Associated with Wastewater Treatment, Reuse, and Disposal.

    PubMed

    Qu, Xiaoyan; Zhao, Yuanyuan; Yu, Ruoren; Li, Yuan; Falzone, Charles; Smith, Gregory; Ikehata, Keisuke

    2016-10-01

    A review of the literature published in 2015 on topics relating to public and environmental health risks associated with wastewater treatment, reuse, and disposal is presented. This review is divided into the following sections: wastewater management, microbial hazards, chemical hazards, wastewater treatment, wastewater reuse, agricultural reuse in different regions, greywater reuse, wastewater disposal, hospital wastewater, industrial wastewater, and sludge and biosolids. PMID:27620110

  4. A novel anoxic-aerobic biofilter process using new composite packing material for the treatment of rural domestic wastewater.

    PubMed

    Pan, L T; Han, Y

    2016-01-01

    A pilot scale experiment was conducted to evaluate the characteristics of contaminants removal in a continuously two-stage biological process composed of an anoxic biofilter (AF) and an biological aerated filter (BAF). This novel process was developed by introducing new composite packing material (MZF) into bioreactors to treat rural domestic wastewater. A comparative study conducted by the same process with ceramsite as packing material under the same conditions showed that a MZF system with a Fe proportion in the packing material performed better in chemical oxygen demand (COD) removal (average 91.5%), ammonia (NH4(+)-N) removal (average 98.3%), total nitrogen (TN) removal (average 64.8%) and total phosphorus (TP) removal (average 90%). After treatment of the MZF system, the concentrations of COD, NH4(+)-N, TN and TP in effluent were 20.3 mg/L, 0.5 mg/L, 11.5 mg/L and 0.3 mg/L, respectively. The simultaneously high efficiencies of nitrification, denitrification and phosphorus removal were achieved by the coupling effects of biological and chemical processes in the MZF system. The results of this study showed that the application of MZF might be a favorable choice as packing material in biofilters for treatment of rural domestic wastewater. PMID:27191571

  5. Leachate/domestic wastewater aerobic co-treatment: A pilot-scale study using multivariate analysis.

    PubMed

    Ferraz, F M; Bruni, A T; Povinelli, J; Vieira, E M

    2016-01-15

    Multivariate analysis was used to identify the variables affecting the performance of pilot-scale activated sludge (AS) reactors treating old leachate from a landfill and from domestic wastewater. Raw leachate was pre-treated using air stripping to partially remove the total ammoniacal nitrogen (TAN). The control AS reactor (AS-0%) was loaded only with domestic wastewater, whereas the other reactor was loaded with mixtures containing leachate at volumetric ratios of 2 and 5%. The best removal efficiencies were obtained for a ratio of 2%, as follows: 70 ± 4% for total suspended solids (TSS), 70 ± 3% for soluble chemical oxygen demand (SCOD), 70 ± 4% for dissolved organic carbon (DOC), and 51 ± 9% for the leachate slowly biodegradable organic matter (SBOM). Fourier transform infrared (FTIR) spectroscopic analysis confirmed that most of the SBOM was removed by partial biodegradation rather than dilution or adsorption of organics in the sludge. Nitrification was approximately 80% in the AS-0% and AS-2% reactors. No significant accumulation of heavy metals was observed for any of the tested volumetric ratios. Principal component analysis (PCA) and partial least squares (PLS) indicated that the data dimension could be reduced and that TAN, SCOD, DOC and nitrification efficiency were the main variables that affected the performance of the AS reactors. PMID:26551262

  6. Treatment of segregated black/grey domestic wastewater using constructed wetlands in the Mediterranean basin: the zer0-m experience.

    PubMed

    Masi, F; El Hamouri, B; Abdel Shafi, H; Baban, A; Ghrabi, A; Regelsberger, M

    2010-01-01

    Concerns about water shortage and pollution have received increased attention over the past few years, especially in developing countries with warm climate. In order to help local water management in these countries, the Euro-Mediterranean Regional Programme (MEDA) has financed the Zer0-m project (E-mail: www.zer0-m.org). As a part of this project, several constructed wetland (CW) pilot systems with different pre-treatments have been implemented in four Technological Demonstration Centres in Egypt, Morocco, Tunisia and Turkey. The aim of this research was to establish appropriate designs for treatment of segregated domestic black (BW) and grey water (GW). We tested several different multistage CW configurations, consisting of horizontal and vertical subsurface flow CW for secondary treatment and free water systems as tertiary stage. CW removal efficiencies of TSS, COD, BOD(5), N-NH(4)(+), N-NO(3)(-), N(tot), total coliforms (TC) were evaluated for each of the implemented systems. The results from this study demonstrate the potential of CWs as a suitable technology for treating segregated domestic wastewater. A very efficient COD reduction (up to 98%) and nitrification (92-99%) was achieved for BW and GW in all systems. CW effluent concentrations were below 15 mg/L for BOD(5), 1 mg/L for N-NO(3)(-) and 0.5 mg/L for N-NH(4)(+) together with acceptable TC counts. Based on these results, we suggest adopting the design parameters used in this study for the treatment of segregated wastewater in the Mediterranean area. PMID:20057095

  7. Domestic Violence

    MedlinePlus

    ... AQ FREQUENTLY ASKED QUESTIONS FAQ083 WOMEN’S HEALTH Domestic Violence • What is domestic violence? • What are the types of abuse? • How can ... available to help abused women? What is domestic violence? Domestic violence is a pattern of threatening or ...

  8. Treatment performance and microorganism community structure of integrated vertical-flow constructed wetland plots for domestic wastewater.

    PubMed

    Wu, Su-qing; Chang, Jun-jun; Dai, Yanran; Wu, Zhen-bin; Liang, Wei

    2013-06-01

    In order to investigate the treatment performance and microorganism mechanism of IVCW for domestic wastewater in central of China, two parallel pilot-scale IVCW systems were built to evaluate purification efficiencies, microbial community structure and enzyme activities. The results showed that mean removal efficiencies were 81.03 % for COD, 51.66 % for total nitrogen (TN), 42.50 % for NH4 (+)-N, and 68.01 % for TP. Significant positive correlations between nitrate reductase activities and TN and NH4 (+)-N removal efficiencies, along with a significant correlation between substrate enzyme activity and operation time, were observed. Redundancy analysis demonstrated gram-negative bacteria were mainly responsible for urease and phosphatase activities, and also played a major role in dehydrogenase and nitrate reductase activities. Meanwhile, anaerobic bacteria, gram-negative bacteria, and saturated FA groups, gram-positive bacteria exhibited good correlations with the removal of COD (p=0.388), N (p=0.236), and TP (p=0.074), respectively. The IVCW system can be used to treat domestic wastewater effectively. PMID:23179215

  9. Molecular detection and treatment of tick-borne pathogens in domestic dogs in Khon Kaen, northeastern Thailand.

    PubMed

    Laummaunwai, Porntip; Sriraj, Pranee; Aukkanimart, Ratchadawan; Boonmars, Thidarut; Boonjaraspinyo, Sirintip; Sangmaneedet, Somboon; Potchimplee, Prapasara; Khianman, Parin; Maleewong, Wanchai

    2014-09-01

    We determined the prevalence of tick-borne pathogens in domestic dogs using microscopy and polymerase chain reaction (PCR) techniques. A total of 303 EDTA blood samples were collected from domestic dogs in Khon Kaen Province, Thailand, in May 2013. Microscopic observation of Giemsa-stained smears and molecular diagnosis using conventional PCR were performed. Infected dogs were treated with imidocarb dipropionate, a combination of imidocarb dipropionate and doxycycline, or doxycycline alone. Seventy-one (23.4%) out of 303 dogs were positive for DNA of tick-borne pathogens. Of the 303 animals, 13.2% and 1.3% were positive for a single infection with Babesia spp or Ehrlichia canis, respec- tively using microscopy; whereas 19.5% and 3.0% were positive using the PCR technique. Co-infection with Babesia spp and E. canis was observed in 0.7%, and coinfection with Hepatozoon canis and E. canis in 0.3%. Infected dogs were treated with the assigned drugs, and elimination of the pathogens was demonstrated by microscopy and PCR. The results indicated that while both microscopic and PCR diagnostic techniques were useful for tick-borne pathogen detection, PCR was more effective. Imidocarb dipropionate and doxycycline were found to be effective for treatment of babesiosis and ehrlichiosis, respectively. The present study suggests that the PCR technique has high sensitivity and specificity for Babesia and Ehrlichia diagnosis as well as for detection of Babesia spp, E. canis and H. canis DNA in EDTA blood specimens. PMID:25417519

  10. Domestic wastewater treatment using tidal-flow cinder bed with Cyperus alternifolius

    SciTech Connect

    Chan, S.Y.; Tsang, Y.F.; Chua, H.

    2008-07-01

    A lab-scale vertical flow cinder bed was set up to treat domestic wastewater. Cinder, which is a common coal waste from electricity generation, was used as the filter medium in the six vertical flow column beds in this study. Three of the six columns were planted with umbrella grass (Cyperus alternifolius) to mimic a wetland system and to investigate the effects of plant on the pollutant removal efficiencies of the column bed systems. The six column beds were divided into three groups, operating with different durations of wet and dry periods. Group 2 column beds, with 4 hours wet periods and 4 hours dry periods, showed the highest carbonaceous removal. Similar ammonia nitrogen removal efficiencies were demonstrated in column beds of group 2 and in column beds of group 3 (6 hours wet periods and 2 hours dry periods). Phosphorus removal efficiencies were not significantly different in all groups of column bed. No significant differences in pollutant removal were observed between planted and unplanted column beds in this study (p > 0.05).

  11. Application of biochemical products as a bioremediation technique for domestic sewage treatment plants.

    PubMed

    Salim, M R; Hassan, R Md; Tan, K Y

    2007-01-01

    Biochemical products have been widely used for treatment of various types of wastewater. The treatment processes with the addition of biochemical products are quite attractive because of their simplicity, minimal use of equipment, they are environmentally friendly and are suitable for the removal of organic pollutants. The purpose of these products is to enhance the activities of beneficial microbes in order to improve treatment performance. This study was carried out to determine the potential of applying biochemical products in assisting and improving the performance of sewage treatment plants. In this study, four biochemical products, namely: Zeolite, Bio-C, Eco-B and Was-D, were applied to the sewage treatment plant. Analyses were carried out on several water quality parameters such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), oil & grease (O&G), phosphorus (P), ammoniacal nitrogen (AN) and sludge thickness (ST). From the results obtained, it can be seen that the overall performance of the treatment plant improved with most of the parameters studied were found to fulfill the DOE Standard B requirements. The performance of Bio-C was found to give better results than other products. PMID:17951865

  12. Microbial fuel cells for energy self-sufficient domestic wastewater treatment-a review and discussion from energetic consideration.

    PubMed

    Lefebvre, Olivier; Uzabiaga, Arnaud; Chang, In Seop; Kim, Byung-Hong; Ng, How Yong

    2011-01-01

    As the microbial fuel cell (MFC) technology is getting nearer to practical applications such as wastewater treatment, it is crucial to consider the different aspects that will make this technology viable in the future. In this paper, we provide information about the specifications of an energy self-sufficient MFC system as a basis to extrapolate on the potential benefits and limits of a future MFC-based wastewater treatment plant. We particularly emphasize on the importance of two crucial parameters that characterize an MFC: its electromotive force (E (emf)) and its internal resistance (R (int)). A numerical projection using state-of-art values (E (emf) = 0.8 V and R (int) = 5 Ω) emphasized on the difficulty at this moment to reach self-sufficiency using a reasonable number of MFCs at the laboratory scale. We found that a realistic number of MFCs to provide enough voltage (=5 V) at a sufficient current (=0.8 A) to power a pump requiring 4 W would be of 13 MFCs in series and 10 stacks of MFCs in parallel, resulting in a total number of 130 MFCs. That would result in a treatment capacity of 144 L of domestic wastewater (0.5 g-COD L(-1)) per day. The total MFC system would be characterized by an internal resistance of 6.5 Ω. PMID:20931187

  13. Mathematical modeling of COD removal via the combined treatment of domestic wastewater and landfill leachate based on the PACT process.

    PubMed

    Fernández Bou, Ángel S; Nascentes, Alexandre Lioi; Costa Pereira, Barbara; Da Silva, Leonardo Duarte Batista; Alberto Ferreira, João; Campos, Juacyara Carbonelli

    2015-01-01

    The experiments performed in this study consisted of 16 batch reactors fed different mixtures of landfill leachate combined with synthetic wastewater treated using the Powdered Activated Carbon Treatment (PACT) process. The objective was to measure the COD mass removal per liter each day for each reactor using two models: the first model combined the variables PAC concentration (0 g·L(-1), 2 g·L(-1), 4 g·L(-1), and 6 g·L(-1)) and leachate rate in the wastewater (0%, 2%, 5%, and 10%), and the second model combined the PAC concentration and the influent COD. The Response Surface Methodology with Central Composite Design was used to describe the response surface of both models considered in this study. Domestic wastewater was produced under controlled conditions in the laboratory where the experiments were performed. The results indicated that the PAC effect was null when the influent did not contain leachate; however, as the concentration of leachate applied to the mixture was increased, the addition of a higher PAC concentration resulted in a better COD mass removal in the reactors. The adjusted R(2) values of the two models were greater than 0.95, and the predicted R(2) values were greater than 0.93. The models may be useful for wastewater treatment companies to calculate PAC requirements in order to meet COD mass removal objectives in combined treatment. PMID:25723064

  14. The effect of aeration and effluent recycling on domestic wastewater treatment in a pilot-plant system of duckweed ponds.

    PubMed

    Ben-shalom, Miriam; Shandalov, Semion; Brenner, Asher; Oron, Gideon

    2014-01-01

    Three pilot-scale duckweed pond (DP) wastewater treatment systems were designed and operated to examine the effect of aeration and effluent recycling on treatment efficiency. Each system consisted of two DPs in series fed by pre-settled domestic sewage. The first system (duckweed+ conventional treatment) was 'natural' and included only duckweed plants. The second system (duckweed aeration) included aeration in the second pond. The third system (duckweed+ aeration+ circulation) included aeration in the second pond and effluent recycling from the second to the first pond. All three systems demonstrated similarly efficient removal of organic matter and nutrients. Supplemental aeration had no effect on either dissolved oxygen levels or on pollutant removal efficiencies. Although recycling had almost no influence on nutrient removal efficiencies, it had a positive impact on chemical oxygen demand and total suspended solids removals due to equalization of load and pH, which suppressed algae growth. Recycling also improved the appearance and growth rate of the duckweed plants, especially during heavy wastewater loads. PMID:24473305

  15. Domestic Violence

    MedlinePlus

    Domestic violence is a type of abuse. It usually involves a spouse or partner, but it can also ... a child, elderly relative, or other family member. Domestic violence may include Physical violence that can lead to ...

  16. Domestic violence

    MedlinePlus

    Domestic violence is when a person uses abusive behavior to control a partner or other family member. The ... of any age, sex, culture, or class. When domestic violence is aimed at a child, it is called ...

  17. Domestic Violence

    MedlinePlus

    Domestic violence is a type of abuse. It usually involves a spouse or partner, but it can also be ... child, elderly relative, or other family member. Domestic violence may include Physical violence that can lead to ...

  18. Comparative evaluation on the performance of bio-rack and shallow pond systems for domestic wastewater treatment.

    PubMed

    Valipour, A; Raman, V K; Badaliansgholikandi, G

    2012-10-01

    Constructed wetlands have been used successfully for treatment of wastewater during the last decades. The bio-rack and shallow pond systems are well engineered wetland process in wastewater treatment. The aim of this study is to compare the potential use of bio-rack and shallow pond systems for domestic wastewater treatment either in presence of high total dissolved solids (TDS) or heavy metal salts. The sewage treatment performance indicates 75.15% & 80.93% chemical oxygen demand (COD), 86.59% & 90.90% biological oxygen demand (BOD5), 27.54% & 15.98% total dissolved solids (TDS), 73.13% & 70.31% total suspended solids (TSS), 8.86% & 3.61% Chlorides, 70.22% & 74.18% ammonia nitrogen (NH3-N), 31.71% & 41.24% phosphate (PO4-P), 92.11% & 96.45% most probable number (MPN) and 93.05% & 98.24% total viable count (TVC) reduction at 10 & 21 h hydraulic retention time (HRT) in bio-rack and shallow pond system respectively. Likewise, the Phragmites sp. and water hyacinth can tolerate TDS up to 9000 and 2000 mg/L. The reduction in TDS is minor (14 & 19%) at the highest tolerable limit whereas the heavy metal reduction is 68 & 65%, 69 & 67%, 67 & 63%, 71 & 69% for Cd, Cu, Ni and Zn in bio-rack and shallow pond system respectively. The overall studies indicate the better treatment efficiency in bio-rack system at low foot print area (91 m2) compared to shallow pond system. PMID:25151708

  19. Accumulation of oil and grease in soils irrigated with greywater and their potential role in soil water repellency.

    PubMed

    Travis, Micheal J; Weisbrod, Noam; Gross, Amit

    2008-05-01

    The potential impact of oil and grease (O and G) to soils irrigated with greywater (GW) was investigated. Greywater streams were sampled and analyzed for O and G content, along with corresponding GW-irrigated soils. Untreated kitchen GW averaged 200 mg L(-1) O and G, over an order of magnitude more than other GW streams. GW-irrigated soils showed O and G accumulation of up to 200 mg kg(-l) within the first 20-cm of depth. To determine the potential effects of such O and G accumulation on water movement in soil, capillary rise and water drop penetration time (WDPT) experiments were conducted. The results showed up to 60% decrease in capillary rise when sand containing 250 mg kg(-1) O and G was used. Interestingly, no additional reduction in capillary rise was observed at concentrations above 250 mg kg(-1). WDPT was observed to increase linearly with increased O and G content, up to 1000 mg kg(-1). This work demonstrated that O and G in GW used for irrigation can accumulate in soil and may lead to a significant reduction in the soils ability to transmit water. PMID:18280539

  20. Challenges and Opportunities for Electrochemical Processes as Next-Generation Technologies for the Treatment of Contaminated Water.

    PubMed

    Radjenovic, Jelena; Sedlak, David L

    2015-10-01

    Electrochemical processes have been extensively investigated for the removal of a range of organic and inorganic contaminants. The great majority of these studies were conducted using nitrate-, perchlorate-, sulfate-, and chloride-based electrolyte solutions. In actual treatment applications, organic and inorganic constituents may have substantial effects on the performance of electrochemical treatment. In particular, the outcome of electrochemical oxidation will depend on the concentration of chloride and bromide. Formation of chlorate, perchlorate, chlorinated, and brominated organics may compromise the quality of the treated effluent. A critical review of recent research identifies future opportunities and research needed to overcome major challenges that currently limit the application of electrochemical water treatment systems for industrial and municipal water and wastewater treatment. Given the increasing interest in decentralized wastewater treatment, applications of electrolytic systems for treatment of domestic wastewater, greywater, and source-separated urine are also included. To support future adoption of electrochemical treatment, new approaches are needed to minimize the formation of toxic byproducts and the loss of efficiency caused by mass transfer limitations and undesired side reactions. Prior to realizing these improvements, recognition of the situations where these limitations pose potential health risks is a necessary step in the design and operation of electrochemical treatment systems. PMID:26370517

  1. Rapid Sand Filtration for Best Practical Treatment of Domestic Wastewater Stabilization Pond Effluent

    ERIC Educational Resources Information Center

    Boatright, D. T.; Lawrence, C. H.

    1977-01-01

    The technical and economic feasibility of constructing and operating a rapid sand filtration sewage treatment system as an adjunct to a waste water stabilization pond is investigated. The study concludes that such units are within the technical and economic constraints of a small community and comply with the EPA criteria. (BT)

  2. Performance and cost evaluation of constructed wetland for domestic waste water treatment.

    PubMed

    Deeptha, V T; Sudarsan, J S; Baskar, G

    2015-09-01

    Root zone treatment through constructed wetlands is an engineered method of purifying wastewater. The aim of the present research was to study the potential of wetland plants Phragmites and Typha in treatment of wastewater and to compare the cost of constructed wetlands with that of conventional treatment systems. A pilot wetland unit of size 2x1x0.9 m was constructed in the campus. 3x3 rows of plants were transplanted into the pilot unit and subjected to wastewater from the hostels and other campus buildings. The raw wastewater and treated wastewater were collected periodically and tested for Total nitrogen (TN),Total Phosphorous (TP), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD). It was observed that this pilot unit reduced the concentrations of TN, TP, BOD and COD by 76, 73, 83 and 86%, respectively, on an average. Root zone system achieved standards for tertiary treatment with low operating costs, low maintenance costs, enhance the landscape, provide a natural habitat for birds, and did not emit any odour. PMID:26521546

  3. A comparative study of five horizontal subsurface flow constructed wetlands using different plant species for domestic wastewater treatment.

    PubMed

    Villaseñor Camacho, J; De Lucas Martínez, A; Gómez Gómez, R; Mena Sanz, J

    2007-12-01

    This project studied domestic wastewater treatment by horizontal subsurface flow (HSSF) constructed wetlands (CW) and compared the effect of four different plant species on the operating conditions, dissolved oxygen (DO), and redox potential (ORP), and their efficiency on pollutants removal. Five HSSF CWs were fed for 10 months with low loaded synthetic domestic wastewater, using theoretical hydraulic residence time of 7.6 days. The plant species under study were the following: Phragmites australis (CW1), Lythrum salicaria (CW3), Cladium mariscus (CW4) and Iris pseudacorus (CW5). CW2 was not planted and this was used as control. Qualitative measurements determined a greater growth of Lythrum salicaria and Iris pseudacorus than the others. Dissolved oxygen concentrations were very low in the entire bulk liquid of all the CWs. Also ORP values were very similar in all wetlands, dealing with facultative anaerobic environments. All planted wetlands improved pollutants removal compared with the unplanted control wetland. The performances in terms of COD, TN, TP and SO4(2-) removal obtained by the different CWs were in the ranges 80-90%, 35-55%, 15-40% and 45-60% respectively. Lythrum salicaria and Iris pseudacorus, which exhibited greater growth, were always the most efficient species that improved not only nutrients plant uptake but also other microbial removal processes probably due to a higher aeration potential, such as nitrification or aerobic respiration. Sulphate reduction was the most important mechanism for COD removal. Cladium mariscus, an autochthonous plant that grows in the south-central Iberian Peninsula, was less efficient than Lythrum salicaria and Iris pseudacorus, but improved the unplanted wetland wastewater efficiency. PMID:18341144

  4. Domestic wastewater treatment as a net energy producer--can this be achieved?

    PubMed

    McCarty, Perry L; Bae, Jaeho; Kim, Jeonghwan

    2011-09-01

    In seeking greater sustainability in water resources management, wastewater is now being considered more as a resource than as a waste-a resource for water, for plant nutrients, and for energy. Energy, the primary focus of this article, can be obtained from wastewater's organic as well as from its thermal content. Also, using wastewater's nitrogen and P nutrients for plant fertilization, rather than wasting them, helps offset the high energy cost of producing synthetic fertilizers. Microbial fuel cells offer potential for direct biological conversion of wastewater's organic materials into electricity, although significant improvements are needed for this process to be competitive with anaerobic biological conversion of wastewater organics into biogas, a renewable fuel used in electricity generation. Newer membrane processes coupled with complete anaerobic treatment of wastewater offer the potential for wastewater treatment to become a net generator of energy, rather than the large energy consumer that it is today. PMID:21749111

  5. Danish guidelines for small-scale constructed wetland systems for onsite treatment of domestic sewage.

    PubMed

    Brix, H; Arias, C A

    2005-01-01

    The Danish Ministry of Environment and Energy has passed new legislation that requires the wastewater from single houses and dwellings in rural areas to be treated adequately before discharge into the aquatic environment. Therefore official guidelines for a number of onsite treatment solutions have been produced. These include guidelines for soakaways, biological sand filters, technical systems as well as different types of constructed wetland systems. This paper summarises briefly the guidelines for horizontal flow constructed wetlands, vertical flow constructed wetlands, and willow systems with no outflow and with soil infiltration. There is still a lack of a compact onsite solution that will fulfil the treatment classes demanding 90% removal of phosphorus. Therefore work is presently being carried out to identify simpler and robust P-removal solutions. PMID:16042237

  6. Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies.

    PubMed

    Shoener, B D; Bradley, I M; Cusick, R D; Guest, J S

    2014-05-01

    The negative energy balance of wastewater treatment could be reversed if anaerobic technologies were implemented for organic carbon oxidation and phototrophic technologies were utilized for nutrient recovery. To characterize the potential for energy positive wastewater treatment by anaerobic and phototrophic biotechnologies we performed a comprehensive literature review and analysis, focusing on energy production (as kJ per capita per day and as kJ m(-3) of wastewater treated), energy consumption, and treatment efficacy. Anaerobic technologies included in this review were the anaerobic baffled reactor (ABR), anaerobic membrane bioreactor (AnMBR), anaerobic fluidized bed reactor (AFB), upflow anaerobic sludge blanket (UASB), anaerobic sequencing batch reactor (ASBR), microbial electrolysis cell (MEC), and microbial fuel cell (MFC). Phototrophic technologies included were the high rate algal pond (HRAP), photobioreactor (PBR), stirred tank reactor, waste stabilization pond (WSP), and algal turf scrubber (ATS). Average energy recovery efficiencies for anaerobic technologies ranged from 1.6% (MFC) to 47.5% (ABR). When including typical percent chemical oxygen demand (COD) removals by each technology, this range would equate to roughly 40-1200 kJ per capita per day or 110-3300 kJ m(-3) of treated wastewater. The average bioenergy feedstock production by phototrophic technologies ranged from 1200-4700 kJ per capita per day or 3400-13 000 kJ m(-3) (exceeding anaerobic technologies and, at times, the energetic content of the influent organic carbon), with usable energy production dependent upon downstream conversion to fuels. Energy consumption analysis showed that energy positive anaerobic wastewater treatment by emerging technologies would require significant reductions of parasitic losses from mechanical mixing and gas sparging. Technology targets and critical barriers for energy-producing technologies are identified, and the role of integrated anaerobic and

  7. Removal of particles in organic filters in experimental treatment systems for domestic wastewater and black water.

    PubMed

    Todt, Daniel; Jenssen, Petter D; Klemenčič, Aleksandra Krivograd; Oarga, Andreea; Bulc, Tjaša Griessler

    2014-01-01

    This study assesses the total suspended solids (TSS) retention capacity of different organic filter media for two potential applications: (i) a polishing unit for package treatment plants and (ii) a pretreatment for blackwater from low-flushing toilets. The results showed that the peat filter media used can be significantly improved in terms of structural stability and TSS removal capacity by mixing it with sawdust. Most of the TSS accumulated in the upper part of the filter material, and filter thickness exceeding 15 cm had no statistically significant effect (P < 0.1) on the TSS treatment performance. The experimental system reached a TSS reduction of 60-70% for blackwater and 80-90% for simulated effluent peaks from a package treatment plant. The main challenge of a full-scale application of an organic filter is the issue of clogging, especially when treating concentrated blackwater. However, this work indicates that a clogged filter media can be regenerated by mixing the uppermost filter layer without significant loss of filter performance regarding TSS. More research is needed to develop an appropriate mechanical unit for automatic filter media regeneration. PMID:24766596

  8. Powdered ZELIAC augmented sequencing batch reactors (SBR) process for co-treatment of landfill leachate and domestic wastewater.

    PubMed

    Mojiri, Amin; Aziz, Hamidi Abdul; Zaman, Nastaein Q; Aziz, Shuokr Qarani; Zahed, Mohammad Ali

    2014-06-15

    Sequencing batch reactor (SBR) is one of the various methods of biological treatments used for treating wastewater and landfill leachate. This study investigated the treatment of landfill leachate and domestic wastewater by adding a new adsorbent (powdered ZELIAC; PZ) to the SBR technique. ZELIAC consists of zeolite, activated carbon, lime stone, rice husk ash, and Portland cement. The response surface methodology and central composite design were used to elucidate the nature of the response surface in the experimental design and describe the optimum conditions of the independent variables, including aeration rate (L/min), contact time (h), and ratio of leachate to wastewater mixture (%; v/v), as well as their responses (dependent variables). Appropriate conditions of operating variables were also optimized to predict the best value of responses. To perform an adequate analysis of the aerobic process, four dependent parameters, namely, chemical oxygen demand (COD), color, ammonia-nitrogen (NH3-N), and phenols, were measured as responses. The results indicated that the PZ-SBR showed higher performance in removing certain pollutants compared with SBR. Given the optimal conditions of aeration rate (1.74 L/min), leachate to wastewater ratio (20%), and contact time (10.31 h) for the PZ-SBR, the removal efficiencies for color, NH3-N, COD, and phenols were 84.11%, 99.01%, 72.84%, and 61.32%, respectively. PMID:24662109

  9. Reducing N2O Emission from a Domestic-Strength Nitrifying Culture by Free Nitrous Acid-Based Sludge Treatment.

    PubMed

    Wang, Dongbo; Wang, Qilin; Laloo, Andrew Elohim; Yuan, Zhiguo

    2016-07-19

    An increase of nitrite in the domestic-strength range is generally recognized to stimulate nitrous oxide (N2O) production by ammonia-oxidizing bacteria (AOB). It was found in this study, however, that N2O emission from a mainstream nitritation system (cyclic nitrite = 25-45 mg of N/L) that was established by free nitrous acid (FNA)-based sludge treatment was not higher but much lower than that from the initial nitrifying system with full conversion of NH4(+)-N to NO3(-)-N. Under dissolved oxygen (DO) levels of 2.5-3.0 mg/L, N2O emission from the nitritation stage was 76% lower than that from the initial stage. Even when the DO level was reduced to 0.3-0.8 mg/L, N2O emission from the nitritation stage was still 40% lower. An investigation of the mechanism showed that FNA treatment caused a shift of the stimulation threshold of nitrite on N2O emission. At the nitritation stage, the maximal N2O emission factor occurred at ∼16 mg of N/(L of nitrite). However, it increased with increasing nitrite in the range of 0-56 mg of N/L at the initial stage. FNA treatment decreased the biomass-specific N2O production rate, suggesting that the enzymes relevant to nitrifier denitrification were inhibited. Microbial analysis revealed that FNA treatment decreased the microbial community diversity but increased the abundances of AOB and denitrifiers. PMID:27294698

  10. The role of sand, marble chips and Typha latifolia in domestic wastewater treatment - a column study on constructed wetlands.

    PubMed

    Kadaverugu, Rakesh; Shingare, Rita P; Raghunathan, Karthik; Juwarkar, Asha A; Thawale, Prashant R; Singh, Sanjeev K

    2016-10-01

    The relative importance of sand, marble chips and wetland plant Typha latifolia is evaluated in constructed wetlands (CWs) for the treatment of domestic wastewater intended for reuse in agriculture. The prototype CWs for the experiments are realized in polyvinyl chloride columns, which are grouped into four treatments, viz. sand (<2 mm) + Typha latifolia (cattail), sand, marble chips (5-20 mm) + cattail and marble chips. The removal percentage of organic and nutritional pollutants from the wastewater is measured at varying hydraulic retention time in the columns. The statistical analysis suggests that the main effects of sand and cattail are found to be significant (p < .05) for the removal of biological oxygen demand and chemical oxygen demand from the wastewater. The presence of cattail significantly (p < .01) contributes to the conversion of total nitrogen in wastewater into [Formula: see text] by fostering the growth of favorable microbes for the nitrification. The removal of [Formula: see text] and turbidity from the wastewater is significantly (p < .01) influenced by sand than the presence of cattail. The maximum [Formula: see text] adsorption capacity of the sand is estimated to be 2.5 mg/g. Marble chips have significantly (p < .01) influenced the removal of [Formula: see text]and its maximum removal capacity is estimated to be 9.3 mg/g. The negative correlation between the filter media biofilm and column hydraulic conductivity is also reported for all the treatments. Thus, the findings of this study elucidate the role of low-cost and easily available filter media and it will guide the environmental practitioners in designing cost-effective CWs for wastewater treatment. PMID:26878342

  11. On-site domestic wastewater treatment by reed bed in the moist subtropics.

    PubMed

    Davison, L; Headley, T; Edmonds, M

    2001-01-01

    This paper summarises the results of studies on four subsurface flow wetlands (reed beds) located in the moist sub-tropical north eastern corner of the Australian state of New South Wales. The reed beds, which are subjected to a variety of effluent types, all have a gravel substrate planted with Phragmites australis. All four units were found to maintain satisfactory treatment performance year round. Mean removal efficiencies ranged from 56% to 90% (SS), 70% to 93% (BOD), 38% to 66% (TN), 87% to 99.8% (Faecal coliforms), and 42% to 70% (TP--with one seasonal result of 0% for the eight year old unit) for the four reed beds. After eight years in operation the oldest reed bed was showing signs of phosphorus saturation with outlet TP concentrations exceeding inlet concentrations on some occasions. The youngest reed bed studied appeared to be operating efficiently after five months. A summer water balance on one of the reed beds revealed an average crop factor of 1.6 and a moisture loss to atmosphere of 40% of influent flow. Treatment performance (particularly for TN and SS) was found to be negatively correlated with rainfall during one study. The paper discusses the implications of the above results for on-site system designers and regulators and identifies areas for further investigation. PMID:11804118

  12. [Evaluation of the treatment effectiveness of domestic G-SCF preparations in experiments on irradiated dogs].

    PubMed

    Rozhdestvenskiĭ, L M; Shliakova, T G; Shchegoleva, R A; Lisina, N I; Zorin, V V

    2013-01-01

    We have evaluated the treatment effectiveness of Leucostim and Neupomax in dogs exposed to radiation at lethal doses of 3 and 3.5 Gy, correspondingly, by testing the dynamics of the blood cell number, first of all, leucocytes and neutrophiles, and the 45-day survival. Supportive therapy for all the dogs, including the control ones, consisted in antibiotic treatment during the acute period of 7-24 days. It was shown that both pre-parations administered consecutively for about 17-21 days after irradiation positively influenced the dynamics of all blood cells but predominantly impacted the neutrophile number dynamics. The latter ones manifested a higher nadir level and an earlier onset of restoration in the G-SCF treated dogs in comparison with the control ones. The tendency to a positive influence on the survival has been shown in Neupomax-treated dogs exposed to 3.5 Gy of radiation (plus about 40%). The results of the experiments were in good accordance with the data by foreign authors who used Neupogen. This allows a conclusion that home-produced G-SCF preparations can replace their foreign analogues. PMID:23700834

  13. High strength domestic wastewater treatment with submerged forward osmosis membrane bioreactor.

    PubMed

    Aftab, Bilal; Khan, Sher Jamal; Maqbool, Tahir; Hankins, Nicholas P

    2015-01-01

    Forward osmosis membranes are less prone to fouling with high rejection of salts, and the osmotic membrane bioreactor (OMBR) can be considered as an innovative membrane technology for wastewater treatment. In this study, a submerged OMBR having a cellulose triacetate membrane, with the active layer facing the feed solution configuration, was operated at different organic loading rates (OLRs), i.e., 0.4, 1.2 and 2.0 kg-COD/(m(3)·d) with chemical oxygen demand (COD) concentrations of 200 mg/L, 600 mg/L and 1,000 mg/L, respectively, to evaluate the performance on varying wastewater strengths. High organic content with sufficient amount of nutrients enhanced the biomass growth. High OLR caused more extrapolymeric substances production and less dewaterability. However, no significant differences in fouling trends and flux rates were observed among different OLR operational conditions. PMID:26114282

  14. Sequential UASB and dual media packed-bed reactors for domestic wastewater treatment - experiment and simulation.

    PubMed

    Rodríguez-Gómez, Raúl; Renman, Gunno

    2016-01-01

    A wastewater treatment system composed of an upflow anaerobic sludge blanket (UASB) reactor followed by a packed-bed reactor (PBR) filled with Sorbulite(®) and Polonite(®) filter material was tested in a laboratory bench-scale experiment. The system was operated for 50 weeks and achieved very efficient total phosphorus (P) removal (99%), 7-day biochemical oxygen demand removal (99%) and pathogenic bacteria reduction (99%). However, total nitrogen was only moderately reduced in the system (40%). A model focusing on simulation of organic material, solids and size of granules was then implemented and validated for the UASB reactor. Good agreement between the simulated and measured results demonstrated the capacity of the model to predict the behaviour of solids and chemical oxygen demand, which is critical for successful P removal and recovery in the PBR. PMID:27332842

  15. Performance of Free Water Surface Constructed Wetland Using Typhalatifolia and Canna Lilies for the Treatment of Domestic Wastewater.

    PubMed

    Shrikhande, Avinash N; Nema, P; Mhaisalkar, Vasant A

    2014-01-01

    Discharge of untreated wastewater or partially treated wastewater into surface water bodies or on to land is a major cause of surface and ground water pollution thereby posing health hazards. Conventional wastewater treatment is generally not preferred for small communities due to higher capital and maintenance costs and lack of skilled supervision required for operation and maintenance. A constructed wetland treatment appears to be an appropriate alternative that can be employed both in developed and developing countries. A constructed wetland system is simple to construct and operate with low cost, and hence worth considering for the treatment of municipal wastewaters, especially from small communities. In this context, the site for carrying out the studies related to wastewater treatment was chosen at Kavikulguru Institute of Technology and Science (KITS), Ramtek, Dist. Nagpur. A Free Water Surface Constructed Wetland (FWSCW) of size 22.00m x 6.50 m x 0.60m was constructed at KITS, Ramtek. The performance of FWS CW system was studied for domestic wastewater treatment with theoretical hydraulic retention times of 10 days, 7 days and 5 days. Important parameters, such as BOD5, COD, TSS, NH4-N, PO4-P, DO, pH and faecal coliforms in both raw and treated wastewaters were monitored during a macrophytes life cycle. Based on the studies, it is concluded that minimum 5 days HRT is necessary for the treatment of wastewater in FWSCW using Typhalatifolia or Canna Lilies. Typhalatifolia is better in removal of pollutants from the wastewater in comparison to Canna Lilies and hence, is recommended for use in constructed wetland. The nutrient uptake capacity of Typhalatifolia is also quite encouraging and hence has great potential for application in treating wastewater from fertilizer industry. During the application of kinetic model, the observed and predicted values in respect of BOD, TSS and NH4-N in case of Typhalatifolia and BOD, COD and TSS in case of Canna Lilies were

  16. COD capture: a feasible option towards energy self-sufficient domestic wastewater treatment

    PubMed Central

    Wan, Junfeng; Gu, Jun; Zhao, Qian; Liu, Yu

    2016-01-01

    Although the activated sludge process, one of the most remarkable engineering inventions in the 20th century, has made significant contribution to wastewater reclamation in the past 100 years, its high energy consumption is posing a serious impact and challenge on the current wastewater industry worldwide and is also inevitably linked to the issue of global climate change. In this study, we argued that substantial improvement in the energy efficiency might be no longer achievable through further optimization of the activated sludge process. Instead, we should devote more effort to the development or the adoption of novel treatment configurations and emerging technologies. Of which an example is A-B process which can significantly improve the energy recovery potential at A-stage, while markedly reduces energy consumption at B-stage. Various configurations of A-B process with energy analysis are thus discussed. It appears highly possible to achieve an overall energy gain in WWTPs with A-B process as a core. PMID:27121339

  17. Occurrence and transport of pharmaceuticals in a karst groundwater system affected by domestic wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Einsiedl, Florian; Radke, Michael; Maloszewski, Piotr

    2010-09-01

    The occurrence of two pharmaceuticals, ibuprofen and diclofenac, in a vulnerable karst groundwater system was investigated. The hydrogeology of the karst system was identified by collecting 3H samples in groundwater over 27 years and by performing tracer tests. The isotopes and tracer data were interpreted by mathematical modeling to estimate the mean transit time of water and to characterize the hydrogeological flow paths in the groundwater system. By this approach, a mean 3H transit time of 4.6 years for the fissured-porous karst aquifer was determined, whereas the fast flowing water in the conduit system showed a mean transit time of days. Both pharmaceuticals which infiltrated along sinkholes and small streams into the karst system were detected in concentrations of up to approximately 1 μg/L in effluent water of the wastewater treatment plants. Diclofenac was present in most samples collected from four springs discharging the karst groundwater to the rivers Altmühl and Anlauter in concentrations between 3.6 and 15.4 ng/L. In contrast, ibuprofen was rarely detected in groundwater. The results of this study suggest that both pharmaceuticals move into the fractured system of the karst system and go into storage. Thus dilution processes are the dominant control on the concentrations of both pharmaceuticals in the fractured system, whereas biodegradation is likely less important.

  18. COD capture: a feasible option towards energy self-sufficient domestic wastewater treatment.

    PubMed

    Wan, Junfeng; Gu, Jun; Zhao, Qian; Liu, Yu

    2016-01-01

    Although the activated sludge process, one of the most remarkable engineering inventions in the 20(th) century, has made significant contribution to wastewater reclamation in the past 100 years, its high energy consumption is posing a serious impact and challenge on the current wastewater industry worldwide and is also inevitably linked to the issue of global climate change. In this study, we argued that substantial improvement in the energy efficiency might be no longer achievable through further optimization of the activated sludge process. Instead, we should devote more effort to the development or the adoption of novel treatment configurations and emerging technologies. Of which an example is A-B process which can significantly improve the energy recovery potential at A-stage, while markedly reduces energy consumption at B-stage. Various configurations of A-B process with energy analysis are thus discussed. It appears highly possible to achieve an overall energy gain in WWTPs with A-B process as a core. PMID:27121339

  19. Bacteria in non-woven textile filters for domestic wastewater treatment.

    PubMed

    Spychała, Marcin; Starzyk, Justyna

    2015-01-01

    The objective of this study was preliminary identification of heterotrophic and ammonia oxidizing bacteria (AOB) cell concentration in the cross-sectional profile of geotextile filters for wastewater treatment. Filters of thicknesses 3.6 and 7.2 mm, made of non-woven textile TS20, were supplied with septic tank effluent and intermittently dosed and filtered under hydrostatic pressure. The cumulative loads of chemical oxygen demand (COD) and total solids were about 1.36 and 1.06 kg/cm2, respectively. The filters under analysis reached a relatively high removal efficiency for organic pollution 70-90% for biochemical oxygen demand (BOD5) and 60-85% for COD. The ammonia nitrogen removal efficiency level proved to be unstable (15-55%). Biomass samples for dry mass identification were taken from two regions: continuously flooded with wastewater and intermittently flooded with wastewater. The culturable heterotrophic bacteria were determined as colony-forming units (CFUs) on microbiological-selective media by means of the plate method. AOB and nitrite oxidizing bacteria (NOB) were examined using the FISH technique. A relatively wide range of heterotrophic bacteria was observed from 7.4×10(5)/cm2 to 3.8×10(6)/cm2 in geotextile layers. The highest concentration of heterotrophic bacteria (3.8×10(6)/cm2) was observed in the first layer of the textile filter. AOB were identified occasionally--about 8-15% of all bacteria colonizing the last filter layer, but occasionally much higher concentrations and ammonia nitrogen efficiency were achieved. Bacteria oxidizing nitrite to nitrate were not observed. The relation of total and organic fraction of biomass to culturable heterotrophic bacteria was also found. PMID:25318829

  20. Modified septic tank-anaerobic filter unit as a two-stage onsite domestic wastewater treatment system.

    PubMed

    Sharma, Meena Kumari; Khursheed, Anwar; Kazmi, Absar Ahmad

    2014-01-01

    This study demonstrates the performance evaluation of a uniquely designed two-stage system for onsite treatment of domestic wastewater. The system consisted of two upflow anaerobic bioreactors, a modified septic tank followed by an upflow anaerobic filter, accommodated within a single cylindrical unit. The system was started up without inoculation at 24 h hydraulic retention time (HRT). It achieved a steady-state condition after 120 days. The system was observed to be remarkably efficient in removing pollutants during steady-state condition with the average removal efficiency of 88.6 +/- 3.7% for chemical oxygen demand, 86.3 +/- 4.9% for biochemical oxygen demand and 91.2 +/- 9.7% for total suspended solids. The microbial analysis revealed a high reduction (>90%) capacity of the system for indicator organism and pathogens. It also showed a very good endurance against imposed hydraulic shock load. Tracer study showed that the flow pattern was close to plug flow reactor. Mean HRT was also found to be close to the designed value. PMID:25145171

  1. Modeling phosphate transport and removal in a compact bed filled with a mineral-based sorbent for domestic wastewater treatment

    NASA Astrophysics Data System (ADS)

    Herrmann, Inga; Jourak, Amir; Gustafsson, Jon Petter; Hedström, Annelie; Lundström, T. Staffan; Viklander, Maria

    2013-11-01

    Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO4)2, successfully simulated the removal of PO4 observed in the experiments.

  2. Modeling phosphate transport and removal in a compact bed filled with a mineral-based sorbent for domestic wastewater treatment.

    PubMed

    Herrmann, Inga; Jourak, Amir; Gustafsson, Jon Petter; Hedström, Annelie; Lundström, T Staffan; Viklander, Maria

    2013-11-01

    Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO4)2, successfully simulated the removal of PO4 observed in the experiments. PMID:24090737

  3. A pilot study of constructed wetlands using duckweed (Lemna gibba L.) for treatment of domestic primary effluent in Israel.

    PubMed

    Ran, Noemi; Agami, Moshe; Oron, Gideon

    2004-05-01

    Constructed wetlands are well known as highly efficient system to treat wastewater from different sources. This treatment system is cost-effective for reuse in desert areas. A continuous flow, free water surface (FWS) pilot wetland using the duckweed plant Lemna gibba L. was constructed at the Blaustein Institute for Desert Research in Kiryat Sde Boker of the Negev, Israel, and operated on domestic primary effluents. Water quality and system efficiency were observed during the experiment for reuse purposes. Results indicated that, hydraulic residence time averaged 4.26+/-0.61d, average influent flow rate was 0.234+/-0.027m(3)/d and hydraulic load 0.22+/-0.03m/d. Hydraulic efficiency in the system was high and allowed good settling conditions. Suspended solids and organic matter removals were the highest and effluent concentrations were 13.1+/-9.7 and 40.3+/-11.9mg/l for TSS and total BOD(5), respectively. Nitrogen removal was lower (10-20%) but slightly increased with higher nitrogen loads. Therefore, nitrogen content in the plants was high (4.3+/-0.5%/kg dry plant). Phosphorus removal was negligible. High removal for fecal coliform (approximately 95%) and effluent turbidity (> 50%) were also observed. PMID:15142784

  4. Immunotoxic potential of aeration lagoon effluents for the treatment of domestic and hospital wastewaters in the freshwater mussel Elliptio complanata.

    PubMed

    Gagné, Francois; André, Chantale; Fortier, Marlène; Fournier, Michel

    2012-01-01

    Municipal wastewaters are major sources of pollution for the aquatic biota. The purpose of this study was to determine the levels of some pharmaceutical products and the immunotoxic potential of a municipal wastewater aeration lagoon for the treatment of the domestic wastewaters of a small town with wastewater inputs from a 400-bed hospital complex. Endemic mussels were collected, caged and placed in the final aeration lagoon and at sites 1 km upstream and 1 km downstream of the effluent outfall in the receiving river for a period of 14 days. The results showed that the final aeration lagoon contained high levels of total coliforms, conductivity and low dissolved oxygen (2.9 mg/L) as well as detectable amounts of trimethoprim, carbamazepine, gemfibrozil, and norfloxacin at concentrations exceeding 50 ng/L. The lagoon effluent was indeed toxic to the mussel specimens, as evidenced by the appearance of mortality after 14 days (10% mortality), decreased mussel weight-to-shell-length ratio and loss of hemocyte viability. The number of adhering hemocytes, phagocytic activity, total nitrite levels and arachidonic cyclooxygenase activity were significantly higher in mussels placed in the final aeration lagoon. A multivariate analysis also revealed that water pH, conductivity, total coliforms and dissolved oxygen were the endpoints most closely linked with phagocytic activity, the amount of adhering hemocytes and loss of hemocyte viability. In conclusion, exposure of mussels to treated aerated lagoon wastewater is deleterious to freshwater mussels where the immune system is compromised. PMID:22893952

  5. Economic Analysis of the Impact of Overseas and Domestic Treatment and Screening Options for Intestinal Helminth Infection among US-Bound Refugees from Asia

    PubMed Central

    Maskery, Brian; Coleman, Margaret S.; Weinberg, Michelle; Zhou, Weigong; Rotz, Lisa; Klosovsky, Alexander; Cantey, Paul T.; Fox, LeAnne M.; Cetron, Martin S.; Stauffer, William M.

    2016-01-01

    Background Many U.S.-bound refugees travel from countries where intestinal parasites (hookworm, Trichuris trichuria, Ascaris lumbricoides, and Strongyloides stercoralis) are endemic. These infections are rare in the United States and may be underdiagnosed or misdiagnosed, leading to potentially serious consequences. This evaluation examined the costs and benefits of combinations of overseas presumptive treatment of parasitic diseases vs. domestic screening/treating vs. no program. Methods An economic decision tree model terminating in Markov processes was developed to estimate the cost and health impacts of four interventions on an annual cohort of 27,700 U.S.-bound Asian refugees: 1) “No Program,” 2) U.S. “Domestic Screening and Treatment,” 3) “Overseas Albendazole and Ivermectin” presumptive treatment, and 4) “Overseas Albendazole and Domestic Screening for Strongyloides”. Markov transition state models were used to estimate long-term effects of parasitic infections. Health outcome measures (four parasites) included outpatient cases, hospitalizations, deaths, life years, and quality-adjusted life years (QALYs). Results The “No Program” option is the least expensive ($165,923 per cohort) and least effective option (145 outpatient cases, 4.0 hospitalizations, and 0.67 deaths discounted over a 60-year period for a one-year cohort). The “Overseas Albendazole and Ivermectin” option ($418,824) is less expensive than “Domestic Screening and Treatment” ($3,832,572) or “Overseas Albendazole and Domestic Screening for Strongyloides” ($2,182,483). According to the model outcomes, the most effective treatment option is “Overseas Albendazole and Ivermectin,” which reduces outpatient cases, deaths and hospitalization by around 80% at an estimated net cost of $458,718 per death averted, or $2,219/$24,036 per QALY/life year gained relative to “No Program”. Discussion Overseas presumptive treatment for U.S.-bound refugees is a cost

  6. Precipitation of phosphate minerals by microorganisms isolated from a fixed-biofilm reactor used for the treatment of domestic wastewater.

    PubMed

    Rivadeneyra, Almudena; Gonzalez-Martinez, Alejandro; Gonzalez-Lopez, Jesus; Martin-Ramos, Daniel; Martinez-Toledo, Maria Victoria; Rivadeneyra, Maria Angustias

    2014-04-01

    The ability of bacteria isolated from a fixed-film bioreactor to precipitate phosphate crystals for the treatment of domestic wastewater in both artificial and natural media was studied. When this was demonstrated in artificial solid media for crystal formation, precipitation took place rapidly, and crystal formation began 3 days after inoculation. The percentage of phosphate-forming bacteria was slightly higher than 75%. Twelve major colonies with phosphate precipitation capacity were the dominant heterotrophic platable bacteria growing aerobically in artificial media. According to their taxonomic affiliations (based on partial sequencing of the 16S rRNA), the 12 strains belonged to the following genera of Gram-negative bacteria: Rhodobacter, Pseudoxanthobacter, Escherichia, Alcaligenes, Roseobacter, Ochrobactrum, Agromyce, Sphingomonas and Paracoccus. The phylogenetic tree shows that most of the identified populations were evolutionarily related to the Alphaproteobacteria (91.66% of sequences). The minerals formed were studied by X-ray diffraction, scanning electron microscopy (SEM), and energy dispersive X-ray microanalysis (EDX). All of these strains formed phosphate crystals and precipitated struvite (MgNH4PO4·6H2O), bobierrite [Mg3(PO4)2·8H2O] and baricite [(MgFe)3(PO4)2·8H2O]. The results obtained in this study show that struvite and spherulite crystals did not show any cell marks. Moreover, phosphate precipitation was observed in the bacterial mass but also near the colonies. Our results suggest that the microbial population contributed to phosphate precipitation by changing the media as a consequence of their metabolic activity. Moreover, the results of this research suggest that bacteria play an active role in the mineral precipitation of soluble phosphate from urban wastewater in submerged fixed-film bioreactors. PMID:24699031

  7. Precipitation of Phosphate Minerals by Microorganisms Isolated from a Fixed-Biofilm Reactor Used for the Treatment of Domestic Wastewater

    PubMed Central

    Rivadeneyra, Almudena; Gonzalez-Martinez, Alejandro; Gonzalez-Lopez, Jesus; Martin-Ramos, Daniel; Martinez-Toledo, Maria Victoria; Rivadeneyra, Maria Angustias

    2014-01-01

    The ability of bacteria isolated from a fixed-film bioreactor to precipitate phosphate crystals for the treatment of domestic wastewater in both artificial and natural media was studied. When this was demonstrated in artificial solid media for crystal formation, precipitation took place rapidly, and crystal formation began 3 days after inoculation. The percentage of phosphate-forming bacteria was slightly higher than 75%. Twelve major colonies with phosphate precipitation capacity were the dominant heterotrophic platable bacteria growing aerobically in artificial media. According to their taxonomic affiliations (based on partial sequencing of the 16S rRNA), the 12 strains belonged to the following genera of Gram-negative bacteria: Rhodobacter, Pseudoxanthobacter, Escherichia, Alcaligenes, Roseobacter, Ochrobactrum, Agromyce, Sphingomonas and Paracoccus. The phylogenetic tree shows that most of the identified populations were evolutionarily related to the Alphaproteobacteria (91.66% of sequences). The minerals formed were studied by X-ray diffraction, scanning electron microscopy (SEM), and energy dispersive X-ray microanalysis (EDX). All of these strains formed phosphate crystals and precipitated struvite (MgNH4PO4·6H2O), bobierrite [Mg3(PO4)2·8H2O] and baricite [(MgFe)3(PO4)2·8H2O]. The results obtained in this study show that struvite and spherulite crystals did not show any cell marks. Moreover, phosphate precipitation was observed in the bacterial mass but also near the colonies. Our results suggest that the microbial population contributed to phosphate precipitation by changing the media as a consequence of their metabolic activity. Moreover, the results of this research suggest that bacteria play an active role in the mineral precipitation of soluble phosphate from urban wastewater in submerged fixed-film bioreactors. PMID:24699031

  8. Domestic Violence

    MedlinePlus

    ... to anyone regardless of race, age, sexual orientation, religion, or gender. Domestic violence affects people of all ... ABOUT The Attorney General Budget & Performance Strategic Plans History AGENCIES BUSINESS Business Opportunities Small & Disadvantaged Business Grants ...

  9. Domestic violence.

    PubMed

    2016-03-30

    Essential facts Domestic violence and abuse includes any incident or repeated incidents of controlling, coercive or threatening behaviour, violence or abuse between family members or intimate partners (including former partners). It can involve psychological, physical, sexual, financial and emotional abuse, as well as 'honour'-based violence and forced marriage. According to the Office for National Statistics, at least 1.4 million women and 700,000 men aged between 16 and 59 experienced domestic abuse in England and Wales in 2013/14 - equivalent to 8.5% of women and 4.5% of men. PMID:27027171

  10. A two-stage microbial fuel cell and anaerobic fluidized bed membrane bioreactor (MFC-AFMBR) system for effective domestic wastewater treatment.

    PubMed

    Ren, Lijiao; Ahn, Yongtae; Logan, Bruce E

    2014-04-01

    Microbial fuel cells (MFCs) are a promising technology for energy-efficient domestic wastewater treatment, but the effluent quality has typically not been sufficient for discharge without further treatment. A two-stage laboratory-scale combined treatment process, consisting of microbial fuel cells and an anaerobic fluidized bed membrane bioreactor (MFC-AFMBR), was examined here to produce high quality effluent with minimal energy demands. The combined system was operated continuously for 50 days at room temperature (∼25 °C) with domestic wastewater having a total chemical oxygen demand (tCOD) of 210 ± 11 mg/L. At a combined hydraulic retention time (HRT) for both processes of 9 h, the effluent tCOD was reduced to 16 ± 3 mg/L (92.5% removal), and there was nearly complete removal of total suspended solids (TSS; from 45 ± 10 mg/L to <1 mg/L). The AFMBR was operated at a constant high permeate flux of 16 L/m(2)/h over 50 days, without the need or use of any membrane cleaning or backwashing. Total electrical energy required for the operation of the MFC-AFMBR system was 0.0186 kWh/m(3), which was slightly less than the electrical energy produced by the MFCs (0.0197 kWh/m(3)). The energy in the methane produced in the AFMBR was comparatively negligible (0.005 kWh/m(3)). These results show that a combined MFC-AFMBR system could be used to effectively treat domestic primary effluent at ambient temperatures, producing high effluent quality with low energy requirements. PMID:24568605

  11. A Two-Stage Microbial Fuel Cell and Anaerobic Fluidized Bed Membrane Bioreactor (MFC-AFMBR) System for Effective Domestic Wastewater Treatment

    PubMed Central

    2014-01-01

    Microbial fuel cells (MFCs) are a promising technology for energy-efficient domestic wastewater treatment, but the effluent quality has typically not been sufficient for discharge without further treatment. A two-stage laboratory-scale combined treatment process, consisting of microbial fuel cells and an anaerobic fluidized bed membrane bioreactor (MFC-AFMBR), was examined here to produce high quality effluent with minimal energy demands. The combined system was operated continuously for 50 days at room temperature (∼25 °C) with domestic wastewater having a total chemical oxygen demand (tCOD) of 210 ± 11 mg/L. At a combined hydraulic retention time (HRT) for both processes of 9 h, the effluent tCOD was reduced to 16 ± 3 mg/L (92.5% removal), and there was nearly complete removal of total suspended solids (TSS; from 45 ± 10 mg/L to <1 mg/L). The AFMBR was operated at a constant high permeate flux of 16 L/m2/h over 50 days, without the need or use of any membrane cleaning or backwashing. Total electrical energy required for the operation of the MFC-AFMBR system was 0.0186 kWh/m3, which was slightly less than the electrical energy produced by the MFCs (0.0197 kWh/m3). The energy in the methane produced in the AFMBR was comparatively negligible (0.005 kWh/m3). These results show that a combined MFC-AFMBR system could be used to effectively treat domestic primary effluent at ambient temperatures, producing high effluent quality with low energy requirements. PMID:24568605

  12. Concurrent Treatment of Substance Abuse, Child Neglect, Bipolar Disorder, Post-Traumatic Stress Disorder, and Domestic Violence: A Case Examination Involving Family Behavior Therapy

    PubMed Central

    Donohue, Brad C.; Romero, Valerie; Herdzik, Karen; Lapota, Holly; Al, Ruwida Abdel; Allen, Daniel N.; Azrin, Nathan H.; Van Hasselt, Vincent B.

    2012-01-01

    High rates of co-occurrence between substance abuse and child neglect have been well documented and especially difficult to treat. As a first step in developing a comprehensive evidence-based treatment for use in this population, the present case examination underscores Family Behavior Therapy (FBT) in the treatment of a mother who evidenced Substance Dependence, child neglect, Post-Traumatic Stress Disorder, Bipolar I Disorder, and domestic violence. Utilizing psychometrically validated self-report inventories and objective urinalysis, treatment was found to result in the cessation of substance use, lower risk of child maltreatment, improved parenting attitudes and practices, and reduced instances of violence in the home. The importance of utilizing validity scales in the assessment of referrals from child welfare settings is discussed, and future directions are reported in light of the results. PMID:23457426

  13. Modelling the effects of on-site greywater reuse and low flush toilets on municipal sewer systems.

    PubMed

    Penn, R; Schütze, M; Friedler, E

    2013-01-15

    On-site greywater reuse (GWR) and installation of water-efficient toilets (WET) reduce urban freshwater demand. Research on GWR and WET has generally overlooked the effects that GWR may have on municipal sewer systems. This paper discusses and quantifies these effects. The effects of GWR and WET, positive and negative, were studied by modelling a representative urban sewer system. GWR scenarios were modelled and analysed using the SIMBA simulation system. The results show that, as expected, the flow, velocity and proportional depth decrease as GWR increases. Nevertheless, the reduction is not evenly distributed throughout the day but mainly occurs during the morning and evening peaks. Examination of the effects of reduced toilet flush volumes revealed that in some of the GWR scenarios flows, velocities and proportional depths in the sewer were reduced, while in other GWR scenarios discharge volumes, velocities and proportional depths did not change. Further, it is indicated that as a result of GWR and installation of WET, sewer blockage rates are not expected to increase significantly. The results support the option to construct new sewer systems with smaller pipe diameters. The analysis shows that as the penetration of GWR systems increase, and with the installation of WET, concentrations of pollutants also increase. In GWR scenarios (when toilet flush volume is not reduced) the increase in pollutant concentrations is lower than the proportional reduction of sewage flow. Moreover, the results show that the spatial distribution of houses reusing GW does not significantly affect the parameters examined. PMID:23220603

  14. Optimization of operating parameters of hybrid vertical down-flow constructed wetland systems for domestic sewerage treatment.

    PubMed

    Huang, Zhujian; Zhang, Xianning; Cui, Lihua; Yu, Guangwei

    2016-09-15

    In this work, three hybrid vertical down-flow constructed wetland (HVDF-CW) systems with different compound substrates were fed with domestic sewage and their pollutants removal performance under different hydraulic loading and step-feeding ratio was investigated. The results showed that the hydraulic loading and step-feeding ratio were two crucial factors determining the removal efficiency of most pollutants, while substrate types only significantly affected the removal of COD and NH4(+)-N. Generally, the lower the hydraulic loading, the better removal efficiency of all contaminants, except for TN. By contrast, the increase of step-feeding ratio would slightly reduce the removal rate of ammonium and TP but obviously promoted the TN removal. Therefore, the optimal operation of this CWs could be achieved with low hydraulic loading combined with 50% of step-feeding ratio when TN removal is the priority, whereas medium or low hydraulic loading without step-feeding would be suitable when TN removal is not taken into consideration. The obtained results in this study can provide us with a guideline for design and optimization of hybrid vertical flow constructed wetland systems to improve the pollutants removal from domestic sewage. PMID:27262033

  15. Treatment of domestic sewage with anoxic/oxic membrane-less microbial fuel cell with intermittent aeration.

    PubMed

    Zhang, Guodong; Lee, Duu-Jong; Cheng, Fangqin

    2016-10-01

    An anoxic/oxic microbial fuel cell (MFC) reactor was applied to treat domestic sewage with intermittent aeration at cathodic chamber. The MFC yielded maximum power density of 2.05W/m(3) at current density 6.05A/m(3), 91.7±0.3% chemical oxygen demand (COD) and 98.2±0.3% ammonia-nitrogen (NH3-N) removals could be reached with most of the hydrophilic (HPI), hydrophobic acid (HPO-A), transphilic acid (TPI-A) of the former being consumed with minimal residual aromatics and the most of NH3-N being converted to N2. When the circuit was opened, the COD removal was dropped to 81.1±0.6% and NH3-N to 80.4±0.9% with most of the HPI, TPI-A and hydrophobic neutral (HPO-N) fractions of the former being consumed with excess aromatic residue and 60% of the latter being converted to NO2(-)-N or NO3(-)-N in effluent. Bioelectrochemical reactions in the tested MFC enhance COD and NH3-N removals from domestic sewage. PMID:27420154

  16. Comparative evaluations of organic matters and nitrogen removal capacities of integrated vertical-flow constructed wetlands: Domestic and nitrified wastewater treatment.

    PubMed

    Chang, Jun J; Liang, Kang; Wu, Su Q; Zhang, Sheng H; Liang, Wei

    2015-01-01

    Two groups of integrated vertical-flow constructed wetland (IVCW) microcosms were established for treating two types of representative wastewater: domestic and nitrified wastewater under two loading rates (LRs) over about two years. Their removal capacities of organic substance and nitrogen as well as the effects of loading rate (LR), outflow temperature and dissolved oxygen (DO) concentration were investigated and compared. Efficient chemical oxygen demand (COD) eliminations were achieved by the IVCWs, with the mass removal rates increasing linearly with the increasing LRs strongly, achieving average value of 56.07 g m(-2) d(-1) at the highest loading rate. Nevertheless, the effluent COD concentrations also increased, with the average value exceeding Class I A discharge standard (< 50 mg L(-1)) for municipal wastewater treatment plants in China at the highest loading rate. Greater total nitrogen (TN) mass removal rates but lower efficiencies were obtained at the high LR for both types of wastewater, and better removal was achieved for nitrified wastewater (NW) in comparison to domestic wastewater (DW), probably due to the prevailing anoxic conditions inside the IVCW beds restricted nitrification process of DW. The influences of LR, temperature and DO on COD removal were slight, but all remarkable on TN reduction. As compared to DO, temperature was more crucial for nitrogen removal, and the temperature dependence coefficient for TN removal of low LR of NW was significantly greater than others. PMID:25901854

  17. Study of the variation of ecotoxicity at different stages of domestic wastewater treatment using Vibrio-qinghaiensis sp.-Q67.

    PubMed

    Ma, Xiaoyan Y; Wang, Xiaochang C; Liu, Yongjun J

    2011-06-15

    A bioassay using the luminescent bacterium Vibrio-qinghaiensis sp.-Q67 associated with solid-phase extraction (SPE) was developed for evaluating the variation of ecotoxicity along with the reduction of organic substances in a domestic wastewater treatment plant employing an oxidation ditch process. With effective elimination of the interference from all inorganic substances by the SPE operation, the ecotoxicity of the water, as expressed by the toxicity impact index, TII(50) (%) after a model-based regression and parameter transformation, was found to decrease from 50.51% in the influent to 25.84% after the grid chamber and then to 1.38% for the secondary effluent, but the final chlorination stage resulted in a slight TII(50) increase. Of the two typical tertiary treatment processes, coagulation could not assist further reduction of the ecotoxicity while carbon adsorption could reduce the TII(50) to as low as 0.96%. When enhanced primary treatment was conducted, the influent TII(50) could be directly reduced to 7.36%. A good correlative relationship was found between the total COD concentration and the TII(50) value at different stages of the wastewater treatment process. PMID:21440989

  18. Treatment of domestic wastewater by an integrated anaerobic fluidized-bed membrane bioreactor under moderate to low temperature conditions.

    PubMed

    Gao, Da-Wen; Hu, Qi; Yao, Chen; Ren, Nan-Qi

    2014-05-01

    The performance of a novel integrated anaerobic fluidized-bed membrane bioreactor (IAFMBR) for treating practical domestic wastewater was investigated at a step dropped temperature from 35, 25, to 15°C. The COD removal was 74.0 ± 3.7%, 67.1 ± 2.9% and 51.1 ± 2.6% at 35, 25 and 15°C, respectively. The COD removal depended both on influent strength and operational temperature. The accumulation of VFAs (Volatile Fatty Acids) was affected by temperature, and acetic acid was the most sensitive one to the decrease of temperature. The methanogenic activity of the sludge decreased eventually and the methane yield was dropped from 0.17 ± 0.03, 0.15 ± 0.02 to 0.10 ± 0.01 L/Ld. And as compared with a mesophilic temperature, a low temperature can accelerate membrane biofouling. Proteins were the dominant matters causing membrane fouling at low temperature and membrane fouling can be mitigated by granular active carbon (GAC) through protein absorption. PMID:24650533

  19. 3,3',5-Triiodo-L-thyronine-like activity in effluents from domestic sewage treatment plants detected by in vitro and in vivo bioassays

    SciTech Connect

    Murata, Tomonori; Yamauchi, Kiyoshi

    2008-02-01

    Thyroid system-disrupting activity in effluents from municipal domestic sewage treatment plants was detected using three in vitro assays and one in vivo assay. Contaminants in the effluents were extracted by solid-phase extraction (SPE) and eluted stepwise with different organic solvents. The majority of the thyroid system-disrupting activity was detected in the dichloromethane/methanol (1/1) fraction after SPE in all three in vitro assays: competitive assays of 3,3',5-[{sup 125}I]triiodo-L-thyronine ([{sup 125}I]T{sub 3}) binding to the plasma protein transthyretin (TTR assay) and thyroid hormone receptor (TR assay) and T{sub 3}-dependent luciferase assay (Luc assay). Subsequent reverse-phase high-performance liquid chromatography (RP-HPLC) of the dichloromethane/methanol (1/1) fraction separated contaminants potent in the TR and Luc assays from those potent in the TTR assay. The contaminants potent in the TR and Luc assays were also potent in an in vivo short-term gene expression assay in Xenopus laevis (Tadpole assay). The present study demonstrated that the effluents from domestic sewage treatment plants contain contaminants with T{sub 3}-like activity of {approx} 10{sup -10} M T{sub 3}-equivalent concentration (T{sub 3}EQ) and that the TR and Luc assays are powerful in vitro bioassays for detecting thyroid system-disrupting activity in effluents. The availability and applicability of these bioassays for screening contaminants with thyroid system-disrupting activity in the water environment are discussed.

  20. A comparative study of the industrial discharges effect on the anaerobic treatment of domestic wastewater in both experimental and pilot-plant scales.

    PubMed

    Saddoud, Ahlem; Abdelkafi, Slim; Aloui, Fathi; Sayadi, Sami

    2010-11-01

    The aim of this study was to compare the effect of industrial discharges on the anaerobic treatment of domestic wastewater in both laboratory and pilot-plant scales at mesophilic conditions. The laboratory experiment results have shown the low process efficiency of anaerobic treatment of DW by the use of an adapted or a non-adapted methanogenic inoculum. These experiments performed in batch digesters were further confirmed by scaling up to a pilot-plant anaerobic membrane bioreactor (MBR). The treatment inefficiency in both laboratory and pilot-plant experiments could be related to the presence of toxic compounds due to the wastewater contamination by industrial discharges. The toxic character of DW was proved by the phytotoxicity and microtoxicity tests. Indeed, the luminescence inhibition percentages started at an average of 21% in the morning and reached more than 84% in the late afternoon. Moreover, the toxicity results have shown a direct relation with methanization results. Indeed, when the average microtoxicity increased to 73%, the average germination index value and the methanization efficiency expressed as the average methane percentage in the produced biogas decreased to 0% and 14.5%, respectively. PMID:21121456

  1. A Comparison of the Structural Factors of the Propensity for Abusiveness Scale for Women and Men in a Domestic Violence Treatment Program.

    PubMed

    Allen, Christopher T; Swan, Suzanne C; Maas, Carl D; Barber, Sara

    2015-08-01

    Court-mandated domestic violence (DV) treatment programs across the country have seen a marked increase in female clients. These programs use a variety of measurement tools to assess the needs of their clients. Increased numbers of women in treatment for DV reflect a need to address the measurement of intimate partner violence (IPV) for both males and females. Unfortunately, the reliability and validity of many of measures used to assess IPV and related constructs for women remains unknown. The current study focuses on a particular measure, the Propensity for Abusiveness Scale (PAS). The PAS is not a measure of abusive behavior per se; rather, it assesses risk factors for abuse, including affective lability, anger expression, trauma symptoms, and harsh parenting experienced by the respondent. Specifically, the current study compares the factor structure and the measurement properties of the PAS for males and females in a sample of 885 (647 female, 238 male) participants in a DV treatment program. Findings indicate that the PAS demonstrated configural, metric, and scalar invariance between the female and male samples. These results suggest that it is appropriate for researchers and clinicians to make comparisons between women and men based on PAS factor scores. PMID:25304668

  2. Effectiveness of a hybrid process combining electro-coagulation and electro-oxidation for the treatment of domestic wastewaters using response surface methodology.

    PubMed

    Daghrir, Rimeh; Drogui, Patrick; Zaviska, François

    2013-01-01

    The performance of a two-stage process combining electro-coagulation (EC) and electro-oxidation (EO) was studied for the treatment of domestic wastewater (DWW) loaded with organic matter. The process was firstly evaluated in terms of its capability of simultaneously producing an oxidant and a coagulant agents using aluminum (Al) (or iron (Fe)) as bipolar and sacrificial electrodes, whereas graphite (Gr) electrodes were used as monopolar electrodes. Relatively high concentrations of chlorine (9.6 mg/min A) and Al (20-40 mg Al/L) or Fe (40-60 mg Fe/L) were produced. Subsequently, the factorial and central composite design methodologies were successively employed to define the optimal operating conditions for total chemical oxygen demand (COD) removal from DWW. Current intensity and treatment time were found to be very meaningful for chemical oxygen demand removal. The effect of these two main factors was around 90% on the investigated response, whereas the type of sacrificial electrode and the other interaction effects represent only 10%. The treatment using aluminum electrode and a current intensity imposed of 0.7 A during 39 min was found to be the optimal conditions in terms of cost/effectiveness. Under these conditions, 78% of COD removal can be obtained for a total cost of 0.78 US $/m(3). PMID:23245306

  3. Cilioprotists as biological indicators for estimating the efficiency of using Gravel Bed Hydroponics System in domestic wastewater treatment

    PubMed Central

    El-Serehy, Hamed A.; Bahgat, Magdy M.; Al-Rasheid, Khaled; Al-Misned, Fahad; Mortuza, Golam; Shafik, Hesham

    2013-01-01

    Interest has increased over the last several years in using different methods for treating sewage. The rapid population growth in developing countries (Egypt, for example, with a population of more than 87 millions) has created significant sewage disposal problems. There is therefore a growing need for sewage treatment solutions with low energy requirements and using indigenous materials and skills. Gravel Bed Hydroponics (GBH) as a constructed wetland system for sewage treatment has been proved effective for sewage treatment in several Egyptian villages. The system provided an excellent environment for a wide range of species of ciliates (23 species) and these organisms were potentially very useful as biological indicators for various saprobic conditions. Moreover, the ciliates provided excellent means for estimating the efficiency of the system for sewage purification. Results affirmed the ability of this system to produce high quality effluent with sufficient microbial reduction to enable the production of irrigation quality water. PMID:24955010

  4. Cilioprotists as biological indicators for estimating the efficiency of using Gravel Bed Hydroponics System in domestic wastewater treatment.

    PubMed

    El-Serehy, Hamed A; Bahgat, Magdy M; Al-Rasheid, Khaled; Al-Misned, Fahad; Mortuza, Golam; Shafik, Hesham

    2014-07-01

    Interest has increased over the last several years in using different methods for treating sewage. The rapid population growth in developing countries (Egypt, for example, with a population of more than 87 millions) has created significant sewage disposal problems. There is therefore a growing need for sewage treatment solutions with low energy requirements and using indigenous materials and skills. Gravel Bed Hydroponics (GBH) as a constructed wetland system for sewage treatment has been proved effective for sewage treatment in several Egyptian villages. The system provided an excellent environment for a wide range of species of ciliates (23 species) and these organisms were potentially very useful as biological indicators for various saprobic conditions. Moreover, the ciliates provided excellent means for estimating the efficiency of the system for sewage purification. Results affirmed the ability of this system to produce high quality effluent with sufficient microbial reduction to enable the production of irrigation quality water. PMID:24955010

  5. Anaerobic treatment as a core technology for energy, nutrients and water recovery from source-separated domestic waste(water).

    PubMed

    Zeeman, Grietje; Kujawa, Katarzyna; de Mes, Titia; Hernandez, Lucia; de Graaff, Marthe; Abu-Ghunmi, Lina; Mels, Adriaan; Meulman, Brendo; Temmink, Hardy; Buisman, Cees; van Lier, Jules; Lettinga, Gatze

    2008-01-01

    Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas production. Post-treatment of the effluent is providing recovery of phosphorus and removal of remaining COD and nitrogen. The total energy saving of the new sanitation concept amounts to 200 MJ/year in comparison with conventional sanitation, moreover 0.14 kg P/p/year and 90 litres of potential reusable water are produced. PMID:18469391

  6. Effect of by-pass and effluent recirculation on nitrogen removal in hybrid constructed wetlands for domestic and industrial wastewater treatment.

    PubMed

    Torrijos, V; Gonzalo, O G; Trueba-Santiso, A; Ruiz, I; Soto, M

    2016-10-15

    Hybrid constructed wetlands (CWs) including subsurface horizontal flow (HF) and vertical flow (VF) steps look for effective nitrification and denitrification through the combination of anaerobic/anoxic and aerobic conditions. Several CW configurations including several configurations of single pass systems (HF + HF, VF + VF, VF + HF), the Bp(VF + HF) arrangement (with feeding by-pass) and the R(HF + VF) system (with effluent recirculation) were tested treating synthetic domestic wastewater. Two HF/VF area ratios (AR) were tested for the VF + HF and Bp(VF + HF) systems. In addition, a R(VF + VF) system was tested for the treatment of a high strength industrial wastewater. The percentage removal of TSS, COD and BOD5 was usually higher than 95% in all systems. The single pass systems showed TN removal below the threshold of 50% and low removal rates (0.6-1.2 g TN/m(2) d), except the VF + VF system which reached 63% and 3.5 g TN/m(2) d removal but only at high loading rates. Bp(VF + HF) systems required by-pass ratios of 40-50% and increased TN removal rates to approximately 50-60% in a sustainable manner. Removal rates depended on the AR value, increasing from 1.6 (AR 2.0) to 5.2 g TN/m(2) d (AR 0.5), both working with synthetic domestic wastewater. On real domestic wastewater the Bp (VF + HF) (AR 0.5 and 30% by-pass) reached 2.5 g TN/m(2) d removal rate. Effluent recirculation significantly improved the TN removal efficiency and rate. The R(HF + VF) system showed stable TN removals of approximately 80% at loading rates ranging from 2 to 8 g TN/m(2) d. High TN removal rates (up to 73% TN and 8.4 g TN/m(2) d) were also obtained for the R(VF + VF) system treating industrial wastewater. PMID:27441816

  7. A Clinical Model in Action in Intensive Residential Treatment: Meeting the Needs of Adolescent Boys Who Have Experienced Domestic Violence

    ERIC Educational Resources Information Center

    Stewart, Janet; Todd, Nick; Kopeck, Cameron

    2010-01-01

    The Habitat Program at Wood's Homes, Calgary, Alberta, is an eight bed residential treatment program for conduct-disordered youth who have been exposed or subjected to high levels of violence in their family home. The program was based on the assumption that working effectively with such youth requires consideration of the background experiences…

  8. FORUM ON INNOVATIVE HAZARDOUS WASTE TREATMENT TECHNOLOGIES: DOMESTIC AND INTERNATIONAL. Third, Dallas, Texas, June 11-13, 1991 - TECHNICAL PAPERS

    EPA Science Inventory

    On June 11 -13,1991, the U.S. Environmental Protection Agency's Technology Innovation Office and Risk Reduction Engineering Laboratory hosted an international conference in Dallas, TX, to exchange solutions to hazardous waste treatment problems. This conference, the Third Forum...

  9. 26 CFR 1.407-1 - Treatment of certain employees of domestic subsidiaries engaged in business outside the United...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.407-1 Treatment... respect to a pension, profit-sharing, or stock bonus plan described in section 401(a), an annuity plan... income for the three-year period immediately preceding the close of its taxable year which ends on...

  10. 26 CFR 1.406-1 - Treatment of certain employees of foreign subsidiaries as employees of the domestic corporation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.406-1 Treatment of certain employees of foreign subsidiaries... with respect to a pension, profit-sharing, or stock bonus plan described in section 401(a), an...

  11. Removal of trace organic contaminants from domestic wastewater: A meta-analysis comparison of sewage treatment technologies.

    PubMed

    Melvin, Steven D; Leusch, Frederic D L

    2016-01-01

    Trace organic contaminants (TrOCs), such as endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products (PPCPs), represent global threats to aquatic animals and ecosystems. A major source of TrOCs in the aquatic environment is via the discharge of treated sewage, so there is an urgent need to evaluate the comparative efficiencies of the most widely used sewage treatment technologies as regards elimination of these compounds from wastewater. To address this need, 976 published articles were compiled focusing on estimates of removal (%) for 20 common environmental TrOCs, from five major sewage treatment technologies: conventional activated sludge (CAS), oxidation ditch (OD), membrane bioreactor (MBR), ponds and constructed wetlands (PCW), and trickling biological filters (TBF). A quantitative meta-analysis was performed to compare standardized relative removal efficiencies (SREs) of the compounds amongst these technologies, and where possible potential sources of heterogeneity were considered (e.g., flow rates and chemical sorption potential). The results indicate that the most widely used CAS treatment and the less common TBF provide comparatively poor overall removal of common organic micropollutants. Membrane bioreactors appear to be capable of achieving the greatest overall removal efficiencies, but the sustainability and economic viability of this option has been questioned. Treatment with OD systems may be more economical while still achieving comparatively high removal efficiencies, and the analysis revealed OD to be the best option for targeting highly potent estrogenic EDCs. This study offers a unique global assessment of TrOC removal via leading sewage treatment technologies, and is an important step in the identification of effective options for treating municipal sewage. PMID:27107223

  12. Developing a model based decision support tool for the identification of sustainable treatment options for domestic wastewater.

    PubMed

    Balkema, A J; Preisig, H A; Otterpohl, R; Lambert, A J; Weijers, S R

    2001-01-01

    To enable decision makers to select sustainable wastewater treatment systems, insight into the sustainability of a wide variety of systems should be provided in a transparent way leaving room for adaptation and interpretation according to the local situation. To provide this insight a structured methodology comparing wastewater treatment systems with respect to sustainability is defined. Similar to life cycle assessment (LCA) three phases can be distinguished: (1) goal and scope definition, (2) inventory analysis, and (3) optimisation and results. In the goal and scope definition we set the system boundaries to include most of the water cycle and part of the food cycle. Furthermore, we defined a multi-disciplinary set of sustainability indicators including technical, economic, environmental, and socio-cultural aspects. In the inventory analysis these sustainability indicators are quantified using simple static models of wastewater unit operations. Selection of unit operations results in a model of a complete wastewater treatment system. In the optimisation phase the decision maker can weigh the different sustainability indicators and select sustainable options through integer programming. PMID:11385856

  13. 13C-NMR Assessment of the Pattern of Organic Matter Transformation during Domestic Wastewater Treatment by Autothermal Aerobic Digestion (ATAD)

    PubMed Central

    Piterina, Anna V.; Barlett, John; Pembroke, J. Tony

    2009-01-01

    The pattern of biodegradation and the chemical changes occurring in the macromolecular fraction of domestic sludge during autothermal thermophilic aerobic digestion (ATAD) was monitored and characterised via solid-state 13C-NMR CP-MAS. Major indexes such as aromaticity, hydrophobicity and alkyl/O-alkyl ratios calculated for the ATAD processed biosolids were compared by means of these values to corresponding indexes reported for sludges of different origin such as manures, soil organic matter and certain types of compost. Given that this is the first time that these techniques have been applied to ATAD sludge, the data indicates that long-chain aliphatics are easily utilized by the microbial populations as substrates for metabolic activities at all stages of aerobic digestion and serve as a key substrate for the temperature increase, which in turn results in sludge sterilization. The ATAD biosolids following treatment had a prevalence of O-alkyl domains, a low aromaticity index (10.4%) and an alkyl/O-alkyl ratio of 0.48 while the hydrophobicity index of the sludge decreased from 1.12 to 0.62 during the treatment. These results have important implications for the evolution of new ATAD modalities particularly in relation to dewatering and the future use of ATAD processed biosolids as a fertilizer, particularly with respect to hydrological impacts on the soil behaviour. PMID:19742161

  14. Organic matter humification in vermifiltration process for domestic sewage sludge treatment by excitation-emission matrix fluorescence and Fourier transform infrared spectroscopy.

    PubMed

    Li, Xiaowei; Xing, Meiyan; Yang, Jian; Zhao, Limin; Dai, Xiaohu

    2013-10-15

    Performance of a conventional biofilter (BF) and two vermifilters (VFs, different heights) containing earthworms was investigated for domestic sewage sludge (DWS) treatment. Humic-acid like (HAL) fraction isolated from the influent sludge (IS) and effluent sludge of BF (ESBF) and VFs (ESVFs) were determined the elemental and functional composition, and structural characteristics using various analytical approaches. Results showed that performance of DWS treatment in the VFs was preferable to that in the BF. With respect to IS-HAL and ESBF-HAL, ESVFs-HAL had low C, H and N contents and C/O ratio, and high O, carboxyl and phenolic OH group contents, and C/N, C/H and E4/E6 ratios, and large molecular weight. The excitation-emission (Ex/Em) matrix spectra revealed that an additional peak was found at Ex/Em wavelength pairs of 345/435 nm in ESVFs-HAL. Further, Fourier transform infrared spectra showed that vermifiltration led to the loss of aliphatic materials and carbohydrates, and the enrichment of carbonyl and phenolic OH groups in HAL fractions. Additionally, the increase in VF height seemed to accelerate humification degree of organic matter in the effluent sludge. In summary, vermifiltration is alternate technology for transformation of organic matter into humic substances, and thus improves quality of DWS as soil organic fertilizer. PMID:23981770

  15. A pilot-scale study of domestic wastewater treatment by different type constructed wetland systems and its potential green house gases emissions

    NASA Astrophysics Data System (ADS)

    Xu, K.; Liu, C.; Gui, P.; Ebie, Y.; Inamori, Y.

    2007-12-01

    Constructed wetland (CV) systems are reliable, flexible in design, and can be built, operated, and maintained at lower costs compared to conventional methods of chemical treatment. There for CW systems are widely used for controlling water-body eutrophication as an ease-operation and cost-effective ecological technology in developing countriens. However, growing attention has been directed to its greenhouse side-effect and global-warming potential in recent years. In this study, three typical constructed wetlands: Vertical Flow (VF), Free Water Surface (FWS) and Subsurface Flow (SF), and combined VF-SF-FWS constructed wetlands were used not only to compare the nutrients removal performance for treatment of low C/N ratio loading domestic wastewater, but also to investigate and compare their CH4 and N2O greenhouse gas emissions characteristics. The results indicated that the four types of CWs had high removal efficiencies for organic matter and SS. Moreover, the combined wetland also showed a comparatively good performance for nitrogen and phosphorus removal, which was 93.6%, 92.8%, 81.3% and 84.5% for BOD5, SS, TN and TP, respectively. It was found that the combined CW and VF CW has a comparative lower global warming potential. The FWS CW had the highest tendency to emit CH4 and led to a higher global warming potential among four types of CWs, which was about the same as 425mgCO2/m2/h.

  16. A comparative study of vertical flow and free-water surface constructed wetlands for low C/N ratio domestic wastewater treatment and its greenhouse gases emission

    NASA Astrophysics Data System (ADS)

    Xu, K.; Liu, C.; Ebie, Y.; Inamori, Y.

    2008-12-01

    Constructed wetland (CW) systems are reliable, flexible in design, and can be built, operated, and maintained at lower costs compared to conventional methods of chemical treatment. Therefore, CW systems are widely used for controlling water-body eutrophication as an ease-operation and cost-effective ecological technology in developing countries. However, growing attention has been directed to its greenhouse side-effect and global-warming potential in recent years. In this study, two typical constructed wetlands: Vertical flow (VF) and Free-water surface (FWS) constructed wetlands were used not only to compare the nutrients removal performance for treatment of low C/N ratio loading domestic wastewater, but also to investigate and compare their CH4 and N2O greenhouse gases emission characteristics. The results indicated that the VF CW showed a comparatively good performance for nitrogen and phosphorus removal than FWS constructed wetland, which was 98.5, 95.9, 93.2 and 90.7 percent for BOD5, SS, NH4-N and TP under 6 days HRT, respectively. It was found that the FWS CW had the higher tendency to emit CH4 than the VF CW during four seasons of one year.

  17. Federal register, Volume 60, No. 234, Wednesday, December 6, 1995 proposed rules. Part 2. 40 CFR part 122, et al. National pollutant discharge elimination system permit application requirements for publicly owned treatment works and other treatment works treating domestic sewage; proposed rule

    SciTech Connect

    1995-12-06

    The Environmental Protection Agency proposes to amend permit application requirements and application forms for publicly owned treatment works (POTWs) and other treatment works treating domestic sewage (TWTDS). TWTDS include facilities that generate sewage sludge, provide commercial treatment of sewage sludge, manufacture a product derived from sewage sludge, or provide disposal of sewage sludge.

  18. Application of patent bio-rack wetland system using Phragmites sp. for domestic wastewater treatment in the presence of high total dissolved solids (TDS) and heavy metal salts.

    PubMed

    Valipour, Alireza; Raman, V Kalyan; Ghole, V S

    2011-07-01

    The quality of water recourses is degrading due to improper wastewater management. The aim of this study is to examine the potential of bio-rack system for treatment of domestic wastewater in the presence of high total dissolved solids (TDS) and heavy metal salts. The bio-rack is a modified wetland system incorporated with the advantages of phytoremediation and attached growth microbial process. The bio-rack is void of the soil strata based root zone system and in lieu a support matrix is provided to enrich the micro flora. The studies indicate that, Phragmites sp. can tolerate TDS up to 9000 mg/L in the bio-rack. The heavy metal removal is a function of phytoaccumulation or phytoextraction, which can lead to morphological deformity if heavy metals exceed the saturation limit of 786 and 5760 mg/kg Cd, 854 and 9280 mg/kg Cu, 639 and 4720 mg/kg Ni, 1187 and 7516 mg/kg Zn, in shoots and roots respectively. The reduction in TDS is marginal (14%) at the highest tolerable limit whereas the heavy metal reduction is 68%, 69%, 67%, 71% for Cd, Cu, Ni and Zn respectively at the outlet of the treatment system. The sewage treatment performance of the bio-rack system for all other parameters is estimated as 75 % Chemical Oxygen Demand (COD), 86 % Biological Oxygen Demand (BOD5), 27% Total Dissolved Solids (TDS), 73% Total Suspended Solids (TSS), 9% chlorides, 70% ammonia nitrogen (NH3-N), 32% phosphate (PO4-P), 92% most probable number (MPN) and 93% total viable count (TVC) reduction. PMID:23029929

  19. Nitrogen removal in a full-scale domestic wastewater treatment plant with activated sludge and trickling filter.

    PubMed

    Nourmohammadi, Davood; Esmaeeli, Mir-Bager; Akbarian, Hossein; Ghasemian, Mohammad

    2013-01-01

    During the last decade, more stringent effluent requirements concerning the nutrients effluent values have been imposed by legislation and social concern. In this study, efficiency of total nitrogen removal in activated sludge and trickling filter processes (AS/TF) was investigated in Tehran North wastewater treatment plant. Biological system in this site was included, anoxic selector tank, aeration tank, final sedimentation, and trickling filter. A part of treated wastewater before chlorination was mixed with supernatant of dewatered sludge and fed to the trickling filter. Supernatant of dewatered sludge with high concentration of NH4-N was diluted by treated wastewater to provide complete nitrification in trickling filter Produced nitrate in trickling filter was arrived to the anoxic tank and converted to nitrogen gas by denitrification. According to the study result, low concentration of organic carbone and high concentration of NH4-N led to nitrification in TF, then nitrate denitrification to nitrogen gas occurred in selector area. NH4-N concentration decreased from 26.8 mg/L to 0.29 mg/L in TF, and NO3-N concentration increased from 8.8 mg/L to 27 mg/L in TF. Consequently, the total nitrogen decreased approximately to 50% in biological process. This efficiency has been observed in returned flow around 24% from final sedimentation into TF. It was concluded that, in comparison with biological nutrient removal processes, this process is very efficient and simple. PMID:23710197

  20. Nitrogen Removal in a Full-Scale Domestic Wastewater Treatment Plant with Activated Sludge and Trickling Filter

    PubMed Central

    Nourmohammadi, Davood; Esmaeeli, Mir-Bager; Akbarian, Hossein; Ghasemian, Mohammad

    2013-01-01

    During the last decade, more stringent effluent requirements concerning the nutrients effluent values have been imposed by legislation and social concern. In this study, efficiency of total nitrogen removal in activated sludge and trickling filter processes (AS/TF) was investigated in Tehran North wastewater treatment plant. Biological system in this site was included, anoxic selector tank, aeration tank, final sedimentation, and trickling filter. A part of treated wastewater before chlorination was mixed with supernatant of dewatered sludge and fed to the trickling filter. Supernatant of dewatered sludge with high concentration of NH4-N was diluted by treated wastewater to provide complete nitrification in trickling filter Produced nitrate in trickling filter was arrived to the anoxic tank and converted to nitrogen gas by denitrification. According to the study result, low concentration of organic carbone and high concentration of NH4-N led to nitrification in TF, then nitrate denitrification to nitrogen gas occurred in selector area. NH4-N concentration decreased from 26.8 mg/L to 0.29 mg/L in TF, and NO3-N concentration increased from 8.8 mg/L to 27 mg/L in TF. Consequently, the total nitrogen decreased approximately to 50% in biological process. This efficiency has been observed in returned flow around 24% from final sedimentation into TF. It was concluded that, in comparison with biological nutrient removal processes, this process is very efficient and simple. PMID:23710197

  1. Effects of earthworms and substrate on diversity and abundance of denitrifying genes (nirS and nirK) and denitrifying rate during rural domestic wastewater treatment.

    PubMed

    Wang, Longmian; Zhang, Yimin; Luo, Xingzhang; Zhang, Jibiao; Zheng, Zheng

    2016-07-01

    This study investigated the performance of an ecological filter (EF) and vermifiltration (VF) system, the effects of substrate and earthworms on the diversity and abundance of denitrifying genes coding for nitrite (nirS and nirK) reductases and on denitrifying rate, and the factors influencing denitrification. The majority of organic matter, ammonia nitrogen and total nitrogen from sewage was removed by the soil layer in both reactors, and their total removal efficiencies increased in VF compared with those in EF. Additionally, substrate in the reactors significantly influenced the Shannon diversity index and abundance of nirS and nirK, as well as the denitrifying rate. However, the earthworms only significantly influenced nirS diversity. Furthermore, evaluation of the factors controlling denitrification implied that increasing NH3-N availability, diversity and abundance of nirS and nirK or decreasing available NO3-N might be responsible for the enhanced denitrification activity obtained using VF for rural domestic wastewater treatment. PMID:27099942

  2. A study on the effects of different hydraulic loading rates (HLR) on pollutant removal efficiency of subsurface horizontal-flow constructed wetlands used for treatment of domestic wastewaters.

    PubMed

    Çakir, Recep; Gidirislioglu, Ali; Çebi, Ulviye

    2015-12-01

    The research into the treatment of domestic wastewaters originating from Büyükdöllük village in Edirne Province was carried out over a 3 year experimental period. The wastewaters of the settlement were treated using a constructed wetland with subsurface horizontal flow, and the effects of different hydraulic loading levels on removal efficiency were studied. In order to achieve this goal, three equal chambers (ponds) of 300 m(2) each were constructed and planted with Phragmites australis. Each of the chambers was loaded with domestic wastewater with average flow discharge creating hydraulic loading rates of 0. m(3) day(-1) m(-2); 0.075 m(3) day(-1) m(-2) and 0.125 m(3) day(-1) m(-2), respectively. According to the results of the study, the inlet levels of the pollutant parameters with carbon origin in the water samples taken from the system entrance are high and the average values for three years are respectively: Biological Oxygen Demand, BOD5 -324.5 mg L(-1); Chemical Oxygen Demand, COD -484,0 mg L(-1); suspended solids (TSS) -147.3 mg L(-1) and Oil and Grease -0.123 mg L(-1). It was also determined that the removal rates of the system were closely dependent on the applied hydraulic loading levels and the highest removal rates of 64.9%, 62.5%, 86.3% and 80.34% for BOD5, COD, TSS and Oil and Grease, respectively, were determined in the pond with a hydraulic loading rate of 0.050 m(3) day(-1) m(-2). Lower removal of 57.9%, 55.5%, 81.4% and 74.5% for BOD5, COD, TSS and Oil and Grease were recorded in the pond with a hydraulic loading rate of 0.075 m(3) day(-1) m(-2); and these values were 49.1%, 47.8%, 70.9% and 62.1% for the pond with a hydraulic loading rate of 0.125 m(3) day(-1) m(-2). High removal rates were also recorded for the other investigated pollution parameters. PMID:26363259

  3. Comparative LCA of decentralized wastewater treatment alternatives for non-potable urban reuse.

    PubMed

    Opher, Tamar; Friedler, Eran

    2016-11-01

    Municipal wastewater (WW) effluent represents a reliable and significant source for reclaimed water, very much needed nowadays. Water reclamation and reuse has become an attractive option for conserving and extending available water sources. The decentralized approach to domestic WW treatment benefits from the advantages of source separation, which makes available simple small-scale systems and on-site reuse, which can be constructed on a short time schedule and occasionally upgraded with new technological developments. In this study we perform a Life Cycle Assessment to compare between the environmental impacts of four alternatives for a hypothetical city's water-wastewater service system. The baseline alternative is the most common, centralized approach for WW treatment, in which WW is conveyed to and treated in a large wastewater treatment plant (WWTP) and is then discharged to a stream. The three alternatives represent different scales of distribution of the WW treatment phase, along with urban irrigation and domestic non-potable water reuse (toilet flushing). The first alternative includes centralized treatment at a WWTP, with part of the reclaimed WW (RWW) supplied back to the urban consumers. The second and third alternatives implement de-centralized greywater (GW) treatment with local reuse, one at cluster level (320 households) and one at building level (40 households). Life cycle impact assessment results show a consistent disadvantage of the prevailing centralized approach under local conditions in Israel, where seawater desalination is the marginal source of water supply. The alternative of source separation and GW reuse at cluster level seems to be the most preferable one, though its environmental performance is only slightly better than GW reuse at building level. Centralized WW treatment with urban reuse of WWTP effluents is not advantageous over decentralized treatment of GW because the supply of RWW back to consumers is very costly in materials and

  4. Drivers and barriers among householders to managing domestic wastewater treatment systems in the Republic of Ireland; implications for risk prevention behaviour

    NASA Astrophysics Data System (ADS)

    Devitt, Catherine; O'Neill, Eoin; Waldron, Richard

    2016-04-01

    Septic systems that are malfunctioning, improperly sited or designed, present a contamination risk to drinking water sources, and subsequently, to human health. However, the international literature identifies gaps in householder knowledge regarding the function and maintenance requirements of septic systems, and also the potential health and environmental risk implications. Allied with householder fears related to the financial cost of risk management, these factors tend to reduce concern to recognise a malfunctioning system. In the Republic of Ireland, three-quarters of households in rural areas utilise an individual domestic wastewater treatment system (or septic system). Consequently, a significant portion of rural households that rely on groundwater sources via private-well use are at risk. Ireland reports one of the highest crude incidence rates of Verotoxigenic Escherichia coli (VTEC) infection in the European Union, and waterborne transmission related to contact with untreated or poorly treated water from private water sources is a factor in its transmission. Following recent Irish legislative change that places a duty of care on individual householders to ensure a proper system functioning, this exploratory study examines perceptions towards the risk management of septic systems among Irish householders. Using qualitative research methods, four focus groups selected on the basis of geographical variation, and two semi-structured interviews were conducted. While most householders agreed that poorly maintained septic systems represented a threat to the environment and to public health, none reported to having a regular maintenance routine in place. Thematic analysis revealed the drivers and barriers to septic system maintenance, and preferences of householders pertaining to communication on septic systems. The Health Belief Model is employed to help understand results. Results suggest that householder capacity to engage in regular risk management is reduced

  5. Multi-perpetrator domestic violence.

    PubMed

    Salter, Michael

    2014-04-01

    A significant proportion of reports of domestic violence against women involve multiple perpetrators. Although the number of perpetrators has been consistently identified as a measure of abuse severity, only a minority of studies of domestic violence examine the role of multiple offenders. Data on multi-perpetrator domestic violence (MDV) is frequently removed from analysis in domestic violence studies, or multi-perpetrator incidents are treated as single-perpetrator incidents. However, the available research links MDV to negative mental and physical health outcomes, intimate partner homicide, homelessness among women, and severe mental illness and suicidality. This article reviews the available prevalence data on MDV and draws together research on the contexts in which MDV takes place. It highlights two groups that are particularly vulnerable to MDV: (1) girls and women partnered to members of gangs and organized crime groups and (2) girls and women in some ethnic minority communities. While discussions of honor in relation to domestic violence are often racialized in Western media, this article highlights the cross-cultural role of masculine honor in collective violence against women in the working class and impoverished communities of majority cultures as well as in migrant and ethnic minority communities. It is clear that such complex forms of violence present a range of challenges for intervention and treatment and the article emphasizes the need for specialized and coordinated modes of investigation, support, and care. PMID:24217092

  6. Ecological risks of home and personal care products in the riverine environment of a rural region in South China without domestic wastewater treatment facilities.

    PubMed

    Zhang, Nai-Sheng; Liu, You-sheng; Van den Brink, Paul J; Price, Oliver R; Ying, Guang-Guo

    2015-12-01

    Home and personal care products (HPCPs) including biocides, benzotriazoles (BTs) and ultraviolet (UV) filters are widely used in our daily life. After use, they are discharged with domestic wastewater into the receiving environment. This study investigated the occurrence of 29 representative HPCPs, including biocides, BTs and UV filters, in the riverine environment of a rural region of South China where no wastewater treatment plants were present, and assessed their potential ecological risks to aquatic organisms. The results showed the detection of 11 biocides and 4 BTs in surface water, and 9 biocides, 3 BTs and 4 UV filters in sediment. In surface water, methylparaben (MeP), triclocarban (TCC), and triclosan (TCS) were detected at all sites with median concentrations of 9.23 ng/L, 2.64 ng/L and 5.39 ng/L, respectively. However, the highest median concentrations were found for clotrimazole (CLOT), 5-methyl-1H-benzotriazole (MBT) and carbendazim (CARB) at 55.6 ng/L, 33.7 ng/L and 13.8 ng/L, respectively. In sediment, TCC, TCS, and UV-326 were detected with their maximum concentrations up to 353 ng/g, 155 ng/g, and 133 ng/g, respectively. The concentrations for those detected HPCPs in surface water and sediment were generally lower in the upper reach (rural area) of Sha River than in the lower reach of Sha River with close proximity to Dongjiang River (Pt-test<0.05), indicating other input sources of HPCPs in the lower reach. Biocides showed significantly higher levels in surface water in the wet season than in the dry and intermediate seasons. Preliminary risk assessment demonstrated that the majority of HPCPs monitored represented low risk in surface waters. There are potentially greater risks to aquatic organisms from the use of TCS and TCC in the wet season than in dry and intermediate seasons in surface waters. This preliminary assessment also indicates potential concerns associated with TCC, TCS, DEET, CARB, and CLOT in sediments, although additional data

  7. [Domestic violence: any progress?].

    PubMed

    Henrion, Roger

    2014-01-01

    modified their behavior, as have the victims, although for a lesser extent. Perpetrators are increasingly subject to restraining orders, with an obligation to undergo treatment and to attend awareness sessions. Victims are also more likely to go to the police. Social workers, self-help groups and, since 2006, psychologists are now available for victim support in police stations. Management of perpetrators has improved. Finally, despite the continuing reluctance of many physicians, an encouraging trend is emerging among younger members of the profession. A recent survey of 1472 French medical students showed that, while 90 % of them said they had received no training in this area, 93 % considered that doctors should play a role and 95 % said they felt highly concerned. Specific university diplomas have been created and domestic violence is now included in the midwifery curriculum. The delicate question of prevention remains to be resolved; a program is currently being tested. PMID:26753414

  8. Domestic Communication Satellites

    ERIC Educational Resources Information Center

    Horowitz, Andrew

    1974-01-01

    A discussion of the Federal Communications Commission's new policy on domestic satellites in light of our 1) military and economic history; 2) corporate interests; 3) citizen surveillance; and 4) media control. (HB)

  9. Police Attitudes toward Domestic Violence Offenders

    ERIC Educational Resources Information Center

    Logan, T. K.; Shannon, Lisa; Walker, Robert

    2006-01-01

    Police attitudes are important in facilitating a sense of safety and comfort in women seeking justice-system support for protection from partner violence. This study examined police attitudes toward sanctions and treatment for domestic violence offenders compared with other violent and nonviolent offenders. In addition, police attitudes toward…

  10. The synergistic effects of dissolved oxygen and pH on N2O production in biological domestic wastewater treatment under nitrifying conditions.

    PubMed

    Li, Pengzhang; Wang, Shuying; Peng, Yongzhen; Liu, Yue; He, Janzhong

    2015-01-01

    Nitrous oxide (N2O) is a potent greenhouse gas, which is produced during nitrifying and denitrifying processes. Some factors and mechanisms affecting N2O emission have been reported in previous literature, but wastewater biological nitrification is accompanied by a dynamic process of dissolved oxygen (DO) consumption and pH reduction, it is more meaningful to study the synergistic effects between DO and pH on N2O production. In this study, the synergistic effects between DO and pH on N2O production were investigated with real domestic wastewater. The results showed that high DO levels and a high pH could improve the oxidation ratio of NH4+-N and the production ratio of NO2--N, while effectively reducing the accumulation ratio of N2O. The NH4+-N was a prerequisite for nitrifier denitrification; when NH4+-N was oxidized completely, there would be no N2O production and an even higher concentration of NO2- The pH factor is shown to directly affect N2O emission, although free ammonia and free nitrous acid which changed with pH had no correlation with N2O emission. There were two reasons: (1) pH can influence the flow direction of electrons afforded by NH2OH oxidation; at high pH, electrons were mainly used for combining H+ and O2 (O2+4H++4e-=2H2O), the accumulation of NO2- cannot be a result of denitrification, and a higher DO can get more electrons to prefer NO2- and (2) NH4+ was the prerequisite for NH2OH oxidation, since NH2OH oxidation process was the way to provide electrons for nitrifier denitrification. PMID:25619120

  11. The role of stress agents as operating factors in formation and functioning of granular aerobic activated sludge at model domestic wastewater treatment.

    PubMed

    Khokhlachev, Nikolay S; Kalenov, Sergei V; Zanina, Olga S; Tyupa, Dmitry V; Baurina, Marina M; Kuznetsov, Alexander Ye

    2014-09-01

    Maintenance of the wastewater treatment plants and increasing the efficiency of existing aerobic biological reactors depend on the stability of activated sludge characteristics under varying wastewater parameters within significant limits and/or influence of some environmental factors. The steady microbial communities observed in biofilms and anaerobic granules of activated sludge can serve as successful samples of formation of the similar aerobic systems. The granular aerobic sludge obtained in the course of our researches is an ideal "plant" on treatment of biogenic pollution at both low and high concentrations. It demonstrates high ability for treatment and stability to adverse factors. To improve aerobic wastewater treatment characteristics, a possibility of using impact of stress conditions upon activated sludge has been studied. Under conditions of fractional hydrogen peroxide addition at diffused lighting, the granular aerobic activated sludge adapted to hydrogen peroxide has been obtained. This sludge has got good sedimentary properties and it differs from the control sample in the species diversity, improved treatment characteristics and also resistance to the stressor. It also endures an impact of one-time hydrogen peroxide addition up to 1.2-1.5 g H2O2/l. The conditions under which the steady aerobic granules of the diameter from 2 to 5 mm were formed with high treatment ability have been chosen. The granules were being stabilized at passages with hydrogen peroxide treatment and they endured up to 2.4-3.0 g/l of one-time H2O2 addition. PMID:24556977

  12. Ozonation effects for excess sludge reduction on bacterial communities composition in a full-scale activated sludge plant for domestic wastewater treatment.

    PubMed

    Chiellini, C; Gori, R; Tiezzi, A; Brusetti, L; Pucciarelli, S; D'Amato, E; Chiavola, A; Sirini, P; Lubello, C; Petroni, G

    2014-01-01

    Activated sludge process is the most widely diffused system to treat wastewater to control the discharge of pollutants into the environment. Microorganisms are responsible for the removal of organic matter, nitrogen, phosphorous and other emerging contaminants. The environmental conditions of biological reactors significantly affects the ecology of the microbial community and, therefore, the performance of the treatment process. In the last years, ozone has been used to reduce excess sludge production by wastewater treatment plants (WWTPs), whose disposal represents one of the most relevant operational costs. The ozonation process has demonstrated to be a viable method to allow a consistent reduction in excess sludge. This study was carried out in a full-scale plant treating municipal wastewater in two parallel lines, one ozonated in the digestion tank and another used as a control. Bacterial communities of samples collected from both lines of digestion thanks were then compared to assess differences related to the ozonation treatment. Data were then analysed with terminal restriction fragment length polymorphism (T-RFLP) analysis on 16S rRNA gene. Differences between bacterial communities of both treated and untreated line appeared 2 weeks after the beginning of the treatment. Results demonstrated that ozonation treatment significantly affected the activated sludge in WWTP. PMID:24701944

  13. Challenging Domestic Violence.

    ERIC Educational Resources Information Center

    Scarlett, Chris

    2002-01-01

    In Britain, a Women's Aid program offers practical support and assistance to abused women. Survivors of domestic abuse can benefit from the opportunity afforded by an objective appraisal of the social context of their personal experiences, facilitated by trained volunteers. (JOW)

  14. Domestic Research at Rand.

    ERIC Educational Resources Information Center

    Rand Corp., Santa Monica, CA.

    This third descriptive inventory of the Rand Corporation's domestic non-military research covers all projects since 1972, as well as its special 1969-1975 program for New York City. For each of over 300 research projects in nine program areas, brief summaries identify the project title and sponsor, beginning and ending dates, person-years of work…

  15. Cogasification of domestic fuels

    SciTech Connect

    Green, A.; Peres, S.; Mullin, J.; Xue, H.

    1995-12-31

    Advanced developments in military aircraft turbine technology have been applied to aeroderivative and large frame combustion turbines. When these advanced turbines are applied to combined cycle systems they result in the highest efficiency electrical generation systems now available. Integrating such a system with a front end coal gasifier is now considered one of the most promising near term Clean Coal Technologies. Gasification of other domestic solid fuels: biomass, MSW and tires could also provide the fuel input to combustion turbines. However, with low oil prices natural gas energy prices are too close to the energy prices of solid fuels to overcome the capital and operating costs of a conventional gasifier. The authors here consider on-site cogasification of domestic fuels to identify feedstock combinations that could be cogasified profitably even when oil prices are low. Coal-natural gas, coal-biomass, biomass-natural gas, coal-MSW are among the promising, domestic combinations. They conclude that cogasification of domestic fuels could serve as a near term clean combustion technology helpful towards trade deficit reduction and achieving global environmental goals.

  16. Domestic Communications Satellites.

    ERIC Educational Resources Information Center

    Network Project Notebook, 1972

    1972-01-01

    The June, 1972 Federal Communications Commission's (FCC) decision allowed an "open skies" policy in regard to domestic communication satellites and raised Liberal opposition to a situation where exclusive and unchecked communications power is now in the hands of private entrepreneurs, primarily the big Defense Department oriented aerospace…

  17. Cat scratch disease from a domestic dog.

    PubMed

    Chen, Tun-Chieh; Lin, Wei-Ru; Lu, Po-Liang; Lin, Chun-Yu; Chen, Yen-Hsu

    2007-02-01

    Cat scratch disease (CSD), caused by Bartonella henselae, is a zoonosis and characterized by self-limited lymphadenopathy. It is transmitted commonly by scratch or bite from cats or kitten. We report an unusual case of CSD caused by a domestic dog scratch that we believe is the first report in Taiwan. A 23-year-old healthy woman developed cervical lymphadenopathy, mild fever, headache, and malaise 3 days after dog scratch. Her symptoms improved after azithromycin treatment. Serology proved B. henselae infection. The owners of a domestic dog might be at risk of "cat" scratch disease. PMID:17493900

  18. Domestic violence in Iranian infertile women

    PubMed Central

    Sheikhan, Zohre; Ozgoli, Giti; Azar, Mahyar; Alavimajd, Hamid

    2014-01-01

    counseling services to women in infertility treatment centers is suggested to prevent domestic violence against infertile women. PMID:25695010

  19. Effective transport for trauma patients under current circumstances in Korea: a single institution analysis of treatment outcomes for trauma patients transported via the domestic 119 service.

    PubMed

    Kim, Jiyoung; Heo, Yunjung; Lee, John C J; Baek, Sukja; Kim, Younghwan; Moon, Jonghwan; Youn, Seok Hwa; Wang, Heejung; Huh, Yo; Jung, Kyoungwon

    2015-03-01

    In Korea, which still lacks a well-established trauma care system, the inability to transport patients to adequate treatment sites in a timely manner is a cause of low trauma patient survival. As such, this study was conducted to serve as a basis for the establishment of a future trauma transport system. We performed a comparative analysis of the transport time, and treatment outcomes between trauma victims transported by ground ambulance (GAMB) and those transported via the helicopter emergency medical service (HEMS) through the National Emergency Management Agency's 119 reporting system, which is similar to the 911 system of the United States, from March 2011 to May 2014. The HEMS-transported patients received treatment instructions, by remote communication, from our trauma specialists from the time of accident reporting; in certain instances, members of the trauma medical staff provided treatment at the scene. A total of 1,626 patients were included in the study; the GAMB and HEMS groups had 1,547 and 79 patients, respectively. The median transport time was different between 2 groups (HEMS, 60 min vs. GAMB, 47 min, P<0.001) but for all patients was 49 min (less than the golden hour). Outcomes were significantly better in the HEMS compared to the GAMB, using the trauma and injury severity score (survival rate, 94.9% vs. 90.5%; Z score, 2.83 vs. -1.96; W score, 6.7 vs. -0.8). A unified 119 service transport system, which includes helicopter transport, and the adoption of a trauma care system that allows active initial involvement of trauma medical personnel, could improve the treatment outcome of trauma patients. PMID:25729259

  20. The effect of pH on enterococci removal in Pistia-, duckweed- and algae-based stabilization ponds for domestic wastewater treatment.

    PubMed

    Awuah, E; Lubberding, H J; Asante, K; Gijzen, H J

    2002-01-01

    A batch scale experiment was conducted to determine the effect of pH on enterococci die-off. A continuous flow system was also established to determine the environmental conditions and their effects on enterococci removal. The batch experiment was conducted for pHs: 4, 5, 7, 9, and 11 under light and dark conditions. Enterococci and DO were measured every day and every other day respectively for nine days. Pathogen removal rates at pH 4, 5, 7, 9 and 11 in the light/dark were (expressed as d(-1)) -2.1/-2.1, -2.1/-1.5, -2.1/-1.5, -2.1/-1.4 and -1.1/-1.0, respectively. DO levels were low, between 0.17 mg/L at pH 4 (light) to 0.56 mg/L at pH 7 (light). The continuous flow system consisted of Pistia (water lettuce), duckweed and algal treatments in series of four ponds with a total retention period of 28 days after two days of anaerobic pre-treatment. After two months of operation, temperature, pH, DO, TDS, and enterococci populations were monitored. A low pH of 4.4 was obtained in the Pistia ponds. Neutral conditions were observed in the duckweed system, while pH values >9 were observed in the algal system. Enterococci decreased from 7.8 x 10(6) to <500/100 ml in all treatment systems after 28 days of treatment with no significant differences between treatments. PMID:11833733

  1. Domestic violence surveillance system:a model

    PubMed Central

    Espinosa, Rafael; Gutiérrez, María Isabel; Mena-Muñoz, Jorge Humberto; Córdoba, Patricia

    2010-01-01

    Objective To develop a domestic violence surveillance system. Material and Methods The strategies included implementation of a standard digitalized reporting and analysis system along with advocacy with community decision makers, strengthening inter-institutional attention networks, consultation for constructing internal flow charts, sensitizing and training network teams in charge of providing health care in cases of domestic violence and supporting improved public policy prevention initiatives. Results A total of 6 893 cases were observed using 2004 and 2005 surveillance system data. The system reports that 80% of the affected were women, followed by 36% children under 14 years. The identified aggressors were mainly females' partners. The system was useful for improving victim services. Conclusions Findings indicate that significant gains were made in facilitating the attention and treatment of victims of domestic violence, improving the procedural response process and enhancing the quality of information provided to policy-making bodies. PMID:18373003

  2. [Domestic violence in Chile].

    PubMed

    León, Tomás; Grez, Marcela; Prato, Juan Andrés; Torres, Rafael; Ruiz, Sergio

    2014-08-01

    According to recent surveys, there is a high prevalence of domestic violence (DV) in Chile. A systematic review was conducted in PubMed, Scielo, and Lilacs with the MesH terms "Chile", "Mental Health", "Health", "Domestic Violence", to explore the impact of DV on health in Chile. Eleven studies fulfilled the inclusion criteria. Two studies were prospective, exploring the influence of DV on maternal-infant health. Nine studies explored the influence of DV on mental health in adults. DV was associated with deranged mental health indicators specially anxiety and depressive symptoms and suicidal ideation. Similar results were observed among mothers who were victims of violence and their children. It is concluded that DV is a complex phenomenon with serious effects on health. However the number of studies on the subject is low and new follow up studies are required. Predictive models for DV and effective preventive measures are urgently needed. PMID:25424674

  3. Occurrence and fate of phthalate esters in full-scale domestic wastewater treatment plants and their impact on receiving waters along the Songhua River in China.

    PubMed

    Gao, Dawen; Li, Zhe; Wen, Zhidan; Ren, Nanqi

    2014-01-01

    The occurrence and fate of six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DOP) were investigated as phthalates passed through three full-scale wastewater treatment plants (WWTPs) with different treatment processes, and ultimately into the recipient Songhua River water in Harbin (China). The six phthalates were detected in the majority of aqueous and solid samples, with DEHP being the most abundant compound. The overall removal efficiency of ΣPAEs in the Cyclic Activated Sludge Technology (CAST) process was over 72%, while both the A/O and A/A/O processes achieved approximately 30% removal. The better performance of the CAST process relative to the Anoxic/Oxic (A/O) and Anaerobic/Anoxic/Oxic (A/A/O) processes was attributed to the indoor-conditions of the CAST plants, which effectively maintained the temperature of the treatment system. The fate of PAEs within two different types of WWTPs (CAST and A/A/O) were assessed qualitatively using mass balances. The results suggested that PAEs removal resulted from both biotransformation and adsorption, of which the former was particularly significant in the CAST process, while the latter was more significant in the A/A/O process. Substantial levels of several PAEs were detected in the Songhua River, especially downstream of the WWTPs, which means that the discharge from WWTPs has a strong impact on the water quality of the Songhua River during cold winter conditions. PMID:24001662

  4. Endorsement of Couples Counseling in a Domestic Violence Case as a Function of Training

    ERIC Educational Resources Information Center

    Bapat, Mona; Tracey, Terence

    2009-01-01

    Reactions of students in helping professions to domestic violence were examined with respect to whether or not the students had any training in domestic violence. One hundred, four students read one of two vignettes describing a domestic violence case and responded to statements related to treatment options. The vignettes differed only in…

  5. Domestically and Generally Violent Forensic Psychiatric Outpatients: Personality Traits and Behavior

    ERIC Educational Resources Information Center

    Hornsveld, Ruud H. J.; Bezuijen, Siemon; Leenaars, Ellie E. M.; Kraaimaat, Floris W.

    2008-01-01

    A group of 63 domestically violent patients and a group of 103 generally violent patients at a Dutch forensic psychiatric outpatient clinic are examined with regard to personality traits and problem behaviors to develop treatment programs for domestically violent patients. The domestically violent patients are more unstable from a psychological…

  6. Degradation of emergent contaminants by UV, UV/H2O2 and neutral photo-Fenton at pilot scale in a domestic wastewater treatment plant.

    PubMed

    De la Cruz, N; Esquius, L; Grandjean, D; Magnet, A; Tungler, A; de Alencastro, L F; Pulgarín, C

    2013-10-01

    This study focuses on the removal of 22 selected micropollutants in an effluent from a municipal wastewater treatment plant (MWTP) at pilot scale. A reactor of 37 L with five low pressure mercury lamps emitting at 254 nm (UV254) was used. The 22 micropollutants include 15 pharmaceuticals, 2 X-Ray contrast medias, 1 corrosion inhibitor and 4 biocides/pesticides. Five of these 22 compounds were used as indicative substances as proposed by the Swiss Federal Office for the Environment (FOEN) (carbamazepine, diclofenac, sulfamethoxazole, benzotriazole and mecoprop). Treatments included UV254 light alone, UV254 + H2O2 and UV254 + H2O2+Fe(3+). Wastewater coming from the MWTP already contained iron with an average total iron of 1.6 mg L(-1). Original pH was not modified and remained between 6 and 7. The parameters changed during the experiments to find the optimal conditions were: wastewater flow rate (2-14 m(3) h(-1)), H2O2 concentration (20-50 mg L(-1)) and Fe (III) concentration (0-4 mg L(-1)). Chemicals removal rates were greater than 80% for the majority of the flow rates tested. Operating costs for the different conditions evaluated were also estimated and compared. PMID:23910229

  7. A collection and treatment system for organic waste and wastewater in a sensitive rural area.

    PubMed

    Malmén, L; Palm, O; Norin, E

    2003-01-01

    In the municipality of Sund, located in a sensitive rural area in Aland, a demonstration project is now carried out with the overall objective to move the most concentrated fractions of wastewater from the coastal area to a treatment plant situated close to arable land. Blackwater and greywater septic sludge from about twenty households and two tourist camps are treated together with energy rich organic material from a nearby potato-chip factory. The collection concept is based on the use of extremely efficient water-saving toilets, with separate systems for the blackwater and greywater in the households. The collected materials are co-treated in a batchwise aerobic thermophilic treatment process (wet composting process), where the materials reach at least 55 degrees C during a minimum of 10 hours. The dry matter content of the collected material was about 2%. After stabilisation and sanitation (by the temperature rise caused by microbial activity during the treatment process), the compost slurry is utilized as a liquid organic fertilizer on arable land. PMID:14753521

  8. Domestic Violence: Protecting Yourself and Your Children

    MedlinePlus

    MENU Return to Web version Domestic Violence: Protecting Yourself and Your Children Domestic Violence: Protecting Yourself and Your Children What is domestic violence? Domestic violence is abuse by a ...

  9. Global Positioning System Derived Performance Measures Are Responsive Indicators of Physical Activity, Disease and the Success of Clinical Treatments in Domestic Dogs

    PubMed Central

    Bruno, Elizabeth A.; Guthrie, James W.; Ellwood, Stephen A.; Mellanby, Richard J.; Clements, Dylan N.

    2015-01-01

    Objective To assess the use of Global Positioning System receiver (GPS) derived performance measures for differentiating between: 1) different outdoor activities in healthy dogs; 2) healthy dogs and those with osteoarthritis; 3) osteoarthritic dogs before and after treatment with non-steroidal anti-inflammatory analgesia. Design Prospective study. Animals Ten healthy dogs and seven dogs with osteoarthritis of the elbow joint (OA dogs). Procedure Healthy dogs were walked on a standard route on-lead, off-lead and subjected to playing activity (chasing a ball) whilst wearing a GPS collar. Each dog was walked for five consecutive days. Dogs with OA were subjected to a single off-lead walk whilst wearing a GPS collar, and then administered oral Carprofen analgesia daily for two weeks. OA dogs were then subjected to the same walk, again wearing a GPS collar. Results GPS derived measures of physical performance could differentiate between on-lead activity, off-lead activity and playing activity in healthy dogs, and between healthy dogs and OA dogs. Variation in the performance measures analysed was greater between individual dogs than for individual dogs on different days. Performance measures could differentiate healthy dogs from OA dogs. OA Dogs treated with Carprofen analgesia showed improvements in their physical performance, which returned to values indistinguishable from those of healthy dogs on nearly all the measures assessed. Conclusions and Clinical Relevance GPS derived measures of physical performance in dogs are objective, easy to quantify, and can be used to gauge the effects of disease and success of clinical treatments. Specific stimuli can be used to modulate physical performance beyond the self-governed boundaries that dogs will naturally express when allowed to exercise freely without stimulation. PMID:25692761

  10. Genetic perspectives on crop domestication

    PubMed Central

    Gross, Briana L.; Olsen, Kenneth M.

    2010-01-01

    The process of crop domestication has long been a topic of active research for biologists, anthropologists and others. Genetic data have proved a powerful resource for drawing inferences on questions regarding the geographical origins of crops, the numbers of independent domestication events for a given crop species, the specific molecular changes underlying domestication traits, and the nature of artificial selection during domestication and subsequent crop improvement. We would argue that these genetic inferences are fundamentally compatible with recent archaeological data that support a view of domestication as a geographically diffuse, gradual process. In this review, we summarize methodologies ranging from QTL mapping to resequencing used in genetic analyses of crop evolution. We also highlight recent major insights regarding the timing and spatial patterning of crop domestication and the distinct genetic underpinnings of domestication, diversification, and improvement traits. PMID:20541451

  11. Performance comparison and economics analysis of waste stabilization ponds and horizontal subsurface flow constructed wetlands treating domestic wastewater: a case study of the Juja sewage treatment works.

    PubMed

    Mburu, Njenga; Tebitendwa, Sylvie M; van Bruggen, Johan J A; Rousseau, Diederik P L; Lens, Piet N L

    2013-10-15

    The performance, effluent quality, land area requirement, investment and operation costs of a full-scale waste stabilization pond (WSP) and a pilot scale horizontal subsurface flow constructed wetland (HSSF-CW) at Jomo Kenyatta University of Agriculture and Technology (JKUAT) were investigated between November 2010 to January 2011. Both systems gave comparable medium to high levels of organic matter and suspended solids removal. However, the WSP showed a better removal for Total Phosphorus (TP) and Ammonium (NH4(+)-N). Based on the population equivalent calculations, the land area requirement per person equivalent of the WSP system was 3 times the area that would be required for the HSSF-CW to treat the same amount of wastewater. The total annual cost estimates consisting of capital, operation and maintenance (O&M) costs were comparable for both systems. However, the evaluation of the capital cost of either system showed that it is largely influenced by the size of the population served, local cost of land and the construction materials involved. Hence, one can select either system in terms of treatment efficiency. When land is available other factor including the volume of wastewater or the investment, and O&M costs determine the technology selection. PMID:23747372

  12. Comparative investigation on integrated vertical-flow biofilters applying sulfur-based and pyrite-based autotrophic denitrification for domestic wastewater treatment.

    PubMed

    Kong, Zhe; Li, Lu; Feng, Chuanping; Dong, Shanshan; Chen, Nan

    2016-07-01

    Two parallel biofilters applying sulfur/pyrite-based autotrophic denitrification were investigated for removing COD, TP and TN by a coordinated process. Results demonstrated good performance by removing 86.32% vs 87.14% COD and 92.56% vs 89.65% NH4(+)-N. Biofilter with sulfur (BS) was superior on nitrate (89.74% vs 80.72%) and TN removal (83.18% vs 70.42%) while biofilter with pyrite (BP) was better on TP removal (82.58% vs 77.40%) and maintaining sulfate (27.56mgL(-1) vs 41.55mgL(-1)) and pH (7.13 vs 6.31). Water-permeable adsorbents lowered clogging risk and buffered loading. Clone library revealed reasons of diversities, pH variation and sulfate accumulation of both biofilters. Sulfur was efficient on denitrification but whose byproducts were troublesome, pyrite produced less byproduct but which was sensitive to organics. This research was the first attempt to systematically compare two promising alternatives and their merits/demerits for rural wastewater on-site treatment. PMID:27015019

  13. Occurrence and removal of butyltin compounds in a waste stabilisation pond of a domestic waste water treatment plant of a rural French town.

    PubMed

    Sabah, A; Bancon-Montigny, C; Rodier, C; Marchand, P; Delpoux, S; Ijjaali, M; Tournoud, M-G

    2016-02-01

    The aim of this study was to investigate the fate and behaviour of butyltin pollutants, including monobutyltin (MBT), dibutylin (DBT), and tributyltin (TBT), in waste stabilisation ponds (WSP). The study was conducted as part of a baseline survey and included five sampling campaigns comprising bottom sludge and the water column from each pond from a typical WSP in France. Butyltins were detected in all raw wastewater and effluents, reflecting their widespread use. Our results revealed high affinity between butyltins and particulate matter and high accumulation of butyltins in the sludge taken from anaerobic ponds. The dissolved butyltins in the influent ranged from 21.5 to 28.1 ng(Sn).L(-1) and in the effluent, from 8.8 to 29.3 ng(Sn).L(-1). The butyltin concentrations in the sludge ranged from 45.1 to 164 and 3.6-8.1 ng(Sn).g(-1) respectively in the first and last ponds. Our results showed an average treatment efficiency of 71% for MBT, 47% for DBT, 55% for TBT. Laboratory sorption experiments enabled the calculation of a distribution coefficient (Kd = 75,000 L.kg-1) between TBT and particulate matter from the WSPs. The Kd explained the accumulation and persistence of the TBT in the sludge after settling of particulate matter. The continuous supply of contaminated raw wastewater and the sorption-desorption processes in the ponds led to incomplete bio- and photolytic degradation and to the persistence of butyltins in dissolved and particulate matrices throughout the survey period. It is thus recommended to use shallow ponds and to pay particular attention when sludge is used for soil amendment. PMID:26624956

  14. War and domestic violence.

    PubMed

    Colson, E

    1995-01-01

    A longterm study (begun in 1956) of the people of four villages in Gwembe District in Zambia provides information on deaths due to Rhodesian action or to Zimbabwean freedom fighters and on deaths due to domestic violence (which is likely to have been underreported because it is considered shameful). During the decade of the 1970s, one woman and three men died from Rhodesian action and 5 women were killed by kinsmen (two husbands, two sons, and one brother). The police left the kin to settle the case of the sister killed by the brother. One man who killed his mother persuaded a younger, unmarried kinsman to be charged and punished in his stead; another left the community. One of the men who killed his wife was released because of his age (he paid damages to his children in accordance with matrilineal tradition); the other was released for lack of evidence. Battered women usually do not press charges against their husbands but may leave them and, if young, marry again. In some cases, battered women seeking divorce have also won compensation for broken bones. Domestic violence may have been especially prevalent in this period because the economic situation deteriorated, men could not find work, and the Rhodesian war added stress and disrupted the local transportation system. In response, men began to drink more heavily and male violence directed against women and men brewed along with locally-produced alcohol. Domestic violence may be exacerbated when men use women as an outlet for their anger and frustration in stressful times of war. PMID:12295013

  15. Animal evolution during domestication: the domesticated fox as a model

    PubMed Central

    Trut, Lyudmila; Oskina, Irina; Kharlamova, Anastasiya

    2009-01-01

    Summary We review the evolution of domestic animals, emphasizing the effect of the earliest steps of domestication on its course. Using the first domesticated species, the dog (Canis familiaris) as an illustration, we describe the evolutionary specificities of the historical domestication, such as the high level and wide range of diversity. We suggest that the process of earliest domestication via unconscious and later conscious selection of human-defined behavioral traits may accelerate phenotypic variations. The review is based on the results of the long-term experiment designed to reproduce early mammalian domestication in the silver fox (Vulpes vulpes) selected for tameability, or amenability to domestication. We describe changes in behavior, morphology and physiology that appeared in the fox during its selection for tameability and that were similar to those observed in the domestic dog. Based on the experimental fox data and survey of relevant data, we discuss the developmental, genetic and possible molecular-genetic mechanisms of these changes. We assign the causative role in evolutionary transformation of domestic animals to selection for behavior and to the neurospecific regulatory genes it affects. PMID:19260016

  16. Domestically acquired fascioliasis in northern California.

    PubMed

    Weisenberg, Scott A; Perlada, David E

    2013-09-01

    Two cases of domestically acquired fascioliasis are reported. Patient One was a 63-year-old male who developed a febrile illness 2 months after eating watercress in Marin County. Patient Two was a 38-year-old male who had eaten watercress with Patient One, and also developed a febrile illness. Both patients had eosinophilia and liver lesions on imaging. Diagnosis was made by serology and treatment was with triclabendazole. PMID:23836562

  17. Domestically Acquired Fascioliasis in Northern California

    PubMed Central

    Weisenberg, Scott A.; Perlada, David E.

    2013-01-01

    Two cases of domestically acquired fascioliasis are reported. Patient One was a 63-year-old male who developed a febrile illness 2 months after eating watercress in Marin County. Patient Two was a 38-year-old male who had eaten watercress with Patient One, and also developed a febrile illness. Both patients had eosinophilia and liver lesions on imaging. Diagnosis was made by serology and treatment was with triclabendazole. PMID:23836562

  18. Core questions in domestication research

    PubMed Central

    Zeder, Melinda A.

    2015-01-01

    The domestication of plants and animals is a key transition in human history, and its profound and continuing impacts are the focus of a broad range of transdisciplinary research spanning the physical, biological, and social sciences. Three central aspects of domestication that cut across and unify this diverse array of research perspectives are addressed here. Domestication is defined as a distinctive coevolutionary, mutualistic relationship between domesticator and domesticate and distinguished from related but ultimately different processes of resource management and agriculture. The relative utility of genetic, phenotypic, plastic, and contextual markers of evolving domesticatory relationships is discussed. Causal factors are considered, and two leading explanatory frameworks for initial domestication of plants and animals, one grounded in optimal foraging theory and the other in niche-construction theory, are compared. PMID:25713127

  19. Domestic and Domesticating Education in the Late Victorian City

    ERIC Educational Resources Information Center

    Heggie, Vanessa

    2011-01-01

    This article explores the various types of domestic education, particularly cookery, available in Manchester between 1870 and 1902. The work of the two local School Boards and the Manchester School of Domestic Economy are shown as part of a complicated network of provision--a mixed economy of welfare, including enthusiastic philanthropists and…

  20. Lousicidal effect of deltamethrin in domestic pigeons.

    PubMed

    Sivajothi, S; Reddy, B Sudhakara

    2016-09-01

    Present study reports the effect of deltamethrin against louse infestation in domestic pigeons. In this study, twelve pigeons infested with Columbicola columbae louse were sprayed with deltamethrin (12.5 %) and another twelve pigeons were kept as control group. The lice intensity was reduced 89 %, 98 % and 100 % on 1st, 7th and 14th day of post treatment in treatment group. Out of twelve pigeons, four pigeons showed sneezing and temporary ocular inflammations after spraying. PMID:27605793

  1. The Complexities of Domestic Violence

    ERIC Educational Resources Information Center

    Dutton, Donald G.

    2007-01-01

    Comments on the article by Robert Bornstein, "The complex relationship between dependency and domestic violence: Converging psychological factors and social forces." Although a more focused examination of the psychological factors involved in domestic violence is welcome, there are some factual errors in Bornstein's article that need attention and…

  2. Replacement Cost of Domestic Crude

    Energy Science and Technology Software Center (ESTSC)

    1994-12-01

    The DEEPWATER model forecasts the replacement cost of domestic crude oil for 13 offshore regions in the lower 48 states. The replacement cost of domestic crude oil is the constant or levelized selling price that will recover the full expense of exploration, development, and productions with a reasonable return on capital.

  3. Tuberculosis in domestic animal species.

    PubMed

    Pesciaroli, M; Alvarez, J; Boniotti, M B; Cagiola, M; Di Marco, V; Marianelli, C; Pacciarini, M; Pasquali, P

    2014-10-01

    M. bovis and M. caprae, members of the Mycobacterium tuberculosis complex (MTC), are the major causative agents of tuberculosis in domestic animals. Notably, M. bovis exhibits a wide host range; the infection has been reported in many domesticated animals and free or captive wildlife. Despite most of them acting as spill-over hosts in particular epidemiological scenarios, some domesticated species as pigs, camelids and goats may display high rates of infection and possibly play a role in the inter-species transmission of the disease. The aim of this review is to make an updated overview of the susceptibility and the role in the transmission of the disease of the most common domesticated animals species such as small ruminants, pigs, horses, camelids, dogs and cats. An overview of the diagnostic approaches to detect the infection in each of the species included in the review is also presented. PMID:25151859

  4. Mutualism breakdown in breadfruit domestication

    PubMed Central

    Xing, Xiaoke; Koch, Alexander M.; Jones, A. Maxwell P.; Ragone, Diane; Murch, Susan; Hart, Miranda M.

    2012-01-01

    During the process of plant domestication, below-ground communities are rarely considered. Some studies have attempted to understand the changes in root symbionts owing to domestication, but little is known about how it influences mycorrhizal response in domesticated crops. We hypothesized that selection for above-ground traits may also result in decreased mycorrhizal abundance in roots. Breadfruit (Artocarpus sp.) has a long domestication history, with a strong geographical movement of cultivars from west to east across the Melanesian and Polynesian islands. Our results clearly show a decrease in arbuscular mycorrhizas (AMs) along a domestication gradient from wild to recently derived cultivars. We showed that the vesicular and arbuscular colonization rate decreased significantly in more recently derived breadfruit cultivars. In addition, molecular analyses of breadfruit roots indicated that AM fungal species richness also responded along the domestication gradient. These results suggest that human-driven selection for plant cultivars can have unintended effects on below-ground mutualists, with potential impacts on the stress tolerance of crops and long-term food security. PMID:21920983

  5. Female domestic violence offenders: their attachment security, trauma symptoms, and personality organization.

    PubMed

    Goldenson, Julie; Geffner, Robert; Foster, Sharon L; Clipson, Clark R

    2007-01-01

    Unlike male domestic violence offenders, female domestic violence offenders have traditionally been overlooked in research and theory, despite the fact that females also have high rates of domestic violence perpetration. Towards the aim of extending extant research on male and female pepetrators of domestic violence, we examined attachment style, trauma symptoms, and personality organization in 33 female offenders receiving mandated treatment for domestic violence. These offenders were compared to 32 nonoffending women receiving psychological treatment. The Experiences in Close Relationships Revised (ECR-Revised) was used to examine adult attachment, the Trauma Symptom Inventory (TSI) was used to examine trauma symptomology, and finally, the Millon Clinical Multiaxial Inventory III (MCMI-III) was used to examine cluster B personality traits. Analyses indicated that female domestic violence offenders reported less attachment security, more trauma-related symptoms, and more personality psychopathology (Antisocial, Borderline, and Dependent Subscales) than did nonoffender clinical comparison women. PMID:18064968

  6. The Therapeutic Efficacy of Domestic Violence Victim Interventions.

    PubMed

    Hackett, Shannon; McWhirter, Paula T; Lesher, Susan

    2016-04-01

    A meta-analysis on domestic violence interventions was conducted to determine overall effectiveness of mental health programs involving women and children in joint treatment. These interventions were further analyzed to determine whether outcomes are differentially affected based on the outcome measure employed. To date, no meta-analyses have been published on domestic violence victim intervention efficacy. The 17 investigations that met study criteria yielded findings indicating that domestic violence interventions have a large effect size (d = .812), which decreases to a medium effect size when compared to control groups (d = .518). Effect sizes were assessed to determine whether treatment differed according to the focus of the outcome measure employed: (a) external stress (behavioral problems, aggression, or alcohol use); (b) psychological adjustment (depression, anxiety, or happiness); (c) self-concept (self-esteem, perceived competence, or internal locus of control); (d) social adjustment (popularity, loneliness, or cooperativeness); (e) family relations (mother-child relations, affection, or quality of interaction); and (f) maltreatment events (reoccurrence of violence, return to partner). Results reveal that domestic violence interventions across all outcome categories yield effects in the medium to large range for both internalized and externalized symptomatology. Implications for greater awareness and support for domestic violence treatment and programming are discussed. PMID:25612799

  7. Phosphorus removal from domestic wastewater by Echinodorus cordifolius L.

    PubMed

    Torit, Jirawan; Siangdung, Wipawan; Thiravetyan, Paitip

    2012-01-01

    This study was to use the plants to remove phosphorus from domestic wastewater which contained high phosphorus concentration. Six higher plant species such as Crinum asiaticum L., Echinodorus cordifolius L., Spathiphyllum clevelandii Schott, Rhizophora apiculata Blume, Thalia dealbata J.fraser., Heliconia psittacorum L.f. were screened for phosphorus removal. Plants were grown in the domestic wastewater and the remaining phosphorus-phosphate concentration in the systems was determined. The results indicated that among studied plants, Echinodorus cordifolius L. was the best for phosphorus removal. Using this plant will improve the quality of domestic wastewater which contained excess phosphorus concentration and induced eutrophication. The relationship between the plants, microorganisms, and soil in the system were also investigated. In this system, adsorption by soil was the major role for phosphorus removal (71%), followed by E. cordifolius (16%), microorganisms in domestic wastewater (7%), and microorganisms in soil (6%). These results indicated the ability of E. cordifolius to remove phosphorus which was superior to that of the microorganisms in the system. Moreover, the rapid phosphorus removal was concomitant to the growth, photosynthesis activity and biomass of E. cordifolius grown in domestic wastewater. The C:N:P ratio of E. cordifolius tissue in the system indicated that elements were taken up from the wastewater. From these results, the suitability of E. cordifolius for domestic wastewater treatment was confirmed. PMID:22416873

  8. State Support of Domestic Production

    SciTech Connect

    Amy Wright

    2007-12-30

    This project was developed in response to a cooperative agreement offering by the U.S. Department of Energy (DOE) and the National Energy Technology Laboratory (NETL) under the State Support of Domestic Production DE-FC26-04NT15456. The Interstate Oil and Gas Compact Commission (IOGCC) performed efforts in support of State programs related to the security, reliability and growth if our nation's domestic production of oil and natural gas. The project objectives were to improve the States ability to monitor the security of oil and gas operations; to maximize the production of domestic oil and natural gas thereby minimizing the threat to national security posed by interruptions in energy imports; to assist States in developing and maintaining high standards of environmental protection; to assist in addressing issues that limit the capacity of the industry; to promote the deployment of the appropriate application of technology for regulatory efficiency; and to inform the public about emerging energy issues.

  9. A Review of On-Site Wastewater Treatment Systems in Western Australia from 1997 to 2011

    PubMed Central

    Gunady, Maria; Shishkina, Natalia; Tan, Henry; Rodriguez, Clemencia

    2015-01-01

    On-site wastewater treatment systems (OWTS) are widely used in Western Australia (WA) to treat and dispose of household wastewater in areas where centralized sewerage systems are unavailable. Septic tanks, aerobic treatment units (ATUs), and composting toilets with greywater systems are among the most well established and commonly used OWTS. However, there are concerns that some OWTS installed in WA are either performing below expected standards or failing. Poorly performing OWTS are often attributed to inadequate installation, inadequate maintenance, poor public awareness, insufficient local authority resources, ongoing wastewater management issues, or inadequate adoption of standards, procedures, and guidelines. This paper is to review the installations and failures of OWTS in WA. Recommendations to the Department of Health Western Australia (DOHWA) and Local Government (LG) in regard to management strategies and institutional arrangements of OWTS are also highlighted. PMID:25960745

  10. A review of on-site wastewater treatment systems in Western Australia from 1997 to 2011.

    PubMed

    Gunady, Maria; Shishkina, Natalia; Tan, Henry; Rodriguez, Clemencia

    2015-01-01

    On-site wastewater treatment systems (OWTS) are widely used in Western Australia (WA) to treat and dispose of household wastewater in areas where centralized sewerage systems are unavailable. Septic tanks, aerobic treatment units (ATUs), and composting toilets with greywater systems are among the most well established and commonly used OWTS. However, there are concerns that some OWTS installed in WA are either performing below expected standards or failing. Poorly performing OWTS are often attributed to inadequate installation, inadequate maintenance, poor public awareness, insufficient local authority resources, ongoing wastewater management issues, or inadequate adoption of standards, procedures, and guidelines. This paper is to review the installations and failures of OWTS in WA. Recommendations to the Department of Health Western Australia (DOHWA) and Local Government (LG) in regard to management strategies and institutional arrangements of OWTS are also highlighted. PMID:25960745

  11. Assessment of Domestic Appliance Noise.

    NASA Astrophysics Data System (ADS)

    Brooks, Jeanette Rosamond

    Available from UMI in association with The British Library. The aims of this study were: (i) to identify the factors involved in eliciting a subjective reaction to domestic appliance noise, (ii) to identify the noise index (or indices) that correlate highly with a subjective reaction to the noise, and (iii) to investigate the contribution of domestic appliance noise to an individual's daily noise dose. Two series of experimental studies were carried out using several examples of each of five types of domestic appliances. One determined the index values of domestic appliance noise--namely L_{WA} (using ISO 3741), L_{pA} , L_{pD}, L _{p}, PNL, L_{Aeq, 30 sec}, L_{Amax} and L_{AX}; the other determined subjective reactions to domestic appliance noise (judgements of noisiness, annoyance, the acceptability of the appliance noise and appraisals of usefulness). The success or failure of the research hypotheses was assessed statistically by analysis of variance, regression analysis, log linear analysis, Hotelling test, bootstrapping, t-test and post-hoc comparisons. Ratings of annoyance, noisiness and the acceptability of the noise of the appliance were found to be interrelated and interdependent, and not influenced by appraisals of usefulness of the appliances. Noisiness ratings were the most consistent of the subjective ratings investigated, and were influenced by the duration of the exposure, and the actual appliance type under investigation. Significant correlations were obtained between noisiness ratings and all the noise indices under investigation. However, statistical analysis demonstrated that L_ {WA} correlated less successfully with noisiness ratings than all other indices. L_ {Amax},L_{Aeq,30 sec }, and L_{AX} indices were the most successful. It is therefore suggested that the labelling of domestic appliance noise consist of L_{WA} and L _{Aeq} as measured in a standardised test environment. The percentage contribution of domestic appliance noise to the total

  12. A Positive Domestic Violence Screen Predicts Future Domestic Violence

    ERIC Educational Resources Information Center

    Houry, Debra; Feldhaus, Kim; Peery, Benjamin; Abbott, Jean; Lowenstein, Steven R.; al-Bataa-de-Montero, Sameerah; Levine, Saul

    2004-01-01

    The objective of this study was to determine if a brief screen for domestic violence (DV) predicts future violence. We conducted a cohort study of adult women who presented to an inner-city emergency department during an 8-week study period. Participants were screened for DV using the Partner Violence Screen (PVS). At 4 months, follow-up telephone…

  13. 26 CFR 1.272-1 - Expenditures relating to disposal of coal or domestic iron ore.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... domestic iron ore. 1.272-1 Section 1.272-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... relating to disposal of coal or domestic iron ore. (a) Introduction. Section 272 provides special treatment... sometimes referred to as a “coal royalty contract” or “iron ore royalty contract”) for the disposal of...

  14. Quality of ground water from private domestic wells

    USGS Publications Warehouse

    DeSimone, Leslie A.; Hamilton, Pixie A.; Gilliom, Robert J.

    2009-01-01

    This article highlights major findings from two USGS reports: DeSimone (2009) and DeSimone and others (2009). These reports can be accessed at http://water.usgs.gov/nawqa. This article is followed by a summary of treatment considerations and options for owners of private domestic wells, written by Cliff Treyens of the National Ground Water Association.

  15. Superheroes and masterminds of plant domestication.

    PubMed

    Martínez-Ainsworth, Natalia E; Tenaillon, Maud I

    2016-01-01

    Domestication is one of the most fundamental changes in the evolution of human societies. The geographical origins of domesticated plants are inferred from archaeology, ecology and genetic data. Scenarios vary among species and include single, diffuse or multiple independent domestications. Cultivated plants present a panel of traits, the "domestication syndrome" that distinguish them from their wild relatives. It encompasses yield-, food usage-, and cultivation-related traits. Most genes underlying those traits are "masterminds" affecting the regulation of gene networks. Phenotypic convergence of domestication traits across species or within species between independently domesticated forms rarely coincides with convergence at the gene level. We review here current data/models that propose a protracted transition model for domestication and investigate the impact of mating system, life cycle and gene flow on the pace of domestication. Finally, we discuss the cost of domestication, pointing to the importance of characterizing adaptive functional variation in wild resources. PMID:27317057

  16. Domestic Violence. Technical Assistance Packet.

    ERIC Educational Resources Information Center

    Join Together, Boston, MA.

    Substance abuse has long been recognized as a precipitating factor in many domestic violence incidents. The main type of substance abuse is alcohol usage. Forty-six percent of the offenders reported being dependent on or abusing alcohol, while another 28% were found to be dependent on opiates, cocaine, marijuana, or inhalants. Nearly two-fifths of…

  17. Natural Rubber from Domestic Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United States is wholly dependent upon imports of natural rubber from tropical countries and is the world’s largest consumer of this strategic raw material. Development of domestic rubber crops will create supply security for this strategic raw material, enhance rural development, and create bio...

  18. Domestic Role Sharing in Sweden.

    ERIC Educational Resources Information Center

    Haas, Linda

    1981-01-01

    Investigated the extent to which Swedish couples (N=128) share domestic tasks using a mail survey. Suggests Swedish couples shared household chores more evenly than American couples. Results indicated variables measuring social exchange theory, family life-cycle stage, and socialization had the greatest influence on role sharing behavior.…

  19. Domestic applications for aerospace waste and water management technologies

    NASA Technical Reports Server (NTRS)

    Disanto, F.; Murray, R. W.

    1972-01-01

    Some of the aerospace developments in solid waste disposal and water purification, which are applicable to specific domestic problems are explored. Also provided is an overview of the management techniques used in defining the need, in utilizing the available tools, and in synthesizing a solution. Specifically, several water recovery processes will be compared for domestic applicability. Examples are filtration, distillation, catalytic oxidation, reverse osmosis, and electrodialysis. Solid disposal methods will be discussed, including chemical treatment, drying, incineration, and wet oxidation. The latest developments in reducing household water requirements and some concepts for reusing water will be outlined.

  20. Genetic analysis of safflower domestication

    PubMed Central

    2014-01-01

    Background Safflower (Carthamus tinctorius L.) is an oilseed crop in the Compositae (a.k.a. Asteraceae) that is valued for its oils rich in unsaturated fatty acids. Here, we present an analysis of the genetic architecture of safflower domestication and compare our findings to those from sunflower (Helianthus annuus L.), an independently domesticated oilseed crop within the same family. We mapped quantitative trait loci (QTL) underlying 24 domestication-related traits in progeny from a cross between safflower and its wild progenitor, Carthamus palaestinus Eig. Also, we compared QTL positions in safflower against those that have been previously identified in cultivated x wild sunflower crosses to identify instances of colocalization. Results We mapped 61 QTL, the vast majority of which (59) exhibited minor or moderate phenotypic effects. The two large-effect QTL corresponded to one each for flower color and leaf spininess. A total of 14 safflower QTL colocalized with previously reported sunflower QTL for the same traits. Of these, QTL for three traits (days to flower, achene length, and number of selfed seed) had cultivar alleles that conferred effects in the same direction in both species. Conclusions As has been observed in sunflower, and unlike many other crops, our results suggest that the genetics of safflower domestication is quite complex. Moreover, our comparative mapping results indicate that safflower and sunflower exhibit numerous instances of QTL colocalization, suggesting that parallel trait transitions during domestication may have been driven, at least in part, by parallel genotypic evolution at some of the same underlying genes. PMID:24502326

  1. Protozoal causes of reproductive failure in domestic ruminants.

    PubMed

    Anderson, M L; Barr, B C; Conrad, P A

    1994-11-01

    Protozoan parasites are a significant cause of abortion and infertility in domestic ruminants. Toxoplasma gondii, a widespread cause of abortion in sheep and goats, and Sarcocystis spp., which cause a common, frequently asymptomatic infection of domestic ruminants, both have a two-host life cycle. Carnivorous definitive hosts spread the infection through their feces and domestic ruminants are intermediate hosts. A similar, recently recognized protozoa, Neospora sp., has emerged as an important cause of reproductive disease, especially as an abortifacient in dairy cattle. Neospora is presumed to also have a two-host life cycle, although the definitive host(s) has not been identified. The venereally transmitted Tritrichomonas foetus is an important cause of pregnancy loss in naturally bred cattle throughout the world. In the absence of effective methods for vaccination or treatment, control of these parasites is based on management procedures to reduce infection and transmission. PMID:7728629

  2. 31 CFR 515.320 - Domestic bank.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Domestic bank. 515.320 Section 515.320... Domestic bank. The term domestic bank shall mean any branch or office within the United States of any of the following which is not a national of a designated foreign country; any bank or trust...

  3. 31 CFR 535.320 - Domestic bank.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Domestic bank. 535.320 Section 535.320....320 Domestic bank. (a) The term domestic bank shall mean any branch or office within the United States of any of the following which is not Iran or an Iranian entity: any bank or trust...

  4. 31 CFR 500.320 - Domestic bank.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Domestic bank. 500.320 Section 500... § 500.320 Domestic bank. The term domestic bank shall mean any branch or office within the United States of any of the following which is not a national of any designated foreign country: Any bank or...

  5. 31 CFR 535.320 - Domestic bank.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Domestic bank. 535.320 Section 535.320....320 Domestic bank. (a) The term domestic bank shall mean any branch or office within the United States of any of the following which is not Iran or an Iranian entity: any bank or trust...

  6. 31 CFR 515.320 - Domestic bank.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Domestic bank. 515.320 Section 515.320... Domestic bank. The term domestic bank shall mean any branch or office within the United States of any of the following which is not a national of a designated foreign country; any bank or trust...

  7. 31 CFR 515.320 - Domestic bank.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Domestic bank. 515.320 Section 515... § 515.320 Domestic bank. The term domestic bank shall mean any branch or office within the United States of any of the following which is not a national of a designated foreign country; any bank or...

  8. 31 CFR 535.320 - Domestic bank.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Domestic bank. 535.320 Section 535... § 535.320 Domestic bank. (a) The term domestic bank shall mean any branch or office within the United States of any of the following which is not Iran or an Iranian entity: any bank or trust...

  9. 31 CFR 515.320 - Domestic bank.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Domestic bank. 515.320 Section 515.320... Domestic bank. The term domestic bank shall mean any branch or office within the United States of any of the following which is not a national of a designated foreign country; any bank or trust...

  10. 31 CFR 535.320 - Domestic bank.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Domestic bank. 535.320 Section 535.320....320 Domestic bank. (a) The term domestic bank shall mean any branch or office within the United States of any of the following which is not Iran or an Iranian entity: any bank or trust...