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Sample records for marketing municipal sludges

  1. Municipal sludge disposal economics

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J L [SRI International, Menlo Park, CA; Bomberger, Jr, D C; Lewis, F M

    1977-10-01

    Costs for disposal of sludges from a municipal wastewater treatment plant normally represents greater than or equal to 25% of the total plant operating cost. The following 5 sludge handling options are considered: chemical conditioning followed by vacuum filtration, and incineration; high-pressure wet-air oxidation and vacuum filtration or filter press prior to incineration; thermal conditioning, vacuum filtraton, and incineration; high-pressure wet-air oxidation and vacuum filtration, with ash to landfill; aerobic or anaerobic digestion, followed by chemical conditioning, vacuum filtration, and disposal on land; and chemical conditioning, followed by a filter press, flash dryer, and sale as fertilizer. The 1st 2 options result in the ultimate disposal of small amounts of ash in a landfill; the digestion options require a significant landfill; the fertilizer option requires a successful marketing and sales effort. To compare the economies of scale for the options, analyses were performed for 3 plant capacities - 10, 100, and 500 mgd; as plant size increases, the economies of scale for incineration system are quite favorable. The anaerobic digestion system has a poorer capital cost-scaling factor. The incinerator options which start with chemical conditioning consume much less electrical power at all treatment plant sizes; incinerator after thermal conditioning uses more electricity but less fuel. Digestion requires no direct external fossil fuel input. The relative use of fuel is constant at all plant sizes for other options. The incinerator options can produce a significant amount of steam which may be used. The anaerobic digestion process can be a significant net producer of fuel gas.

  2. Synchronous municipal sewerage-sludge stabilization.

    Science.gov (United States)

    Bukuru, Godefroid; Jian, Yang

    2005-01-01

    A study on a pilot plant accomplishing synchronous municipal sewerage-sludge stabilization was conducted at a municipal sewerage treatment plant. Stabilization of sewerage and sludge is achieved in three-step process: anaerobic reactor, roughing filter and a microbial-earthworm-ecofilter. The integrated ecofilter utilizes an artificial ecosystem to degrade and stabilize the sewerage and sludge. When the hydraulic retention time(HRT) of the anaerobic reactor is 6 h, the hydraulic load(HL) of the bio-filter is 16 m3/(m2 x d), the HL of the eco-filter is 5 m3/(m2 x d), the recycle ratio of nitrified liquor is 1.5, the removal efficiency is 83%-89% for COD(Cr), 94%-96% for BOD5, 96%-98% for SS, and 76%-95% for NH3-N. The whole system realizes the zero emission of sludge, and has the characteristics of saving energy consumption and operational costs.

  3. Adsorption of Phthalates on Municipal Activated Sludge

    Directory of Open Access Journals (Sweden)

    Hongbo Wang

    2017-01-01

    Full Text Available Phthalates (PAEs are commonly detected in discharge of municipal wastewater treatment plants. This study investigated the removal of six typical PAEs with activated sludge and the results revealed that concentrations of aqueous PAEs decreased rapidly during the beginning 15 min and reached equilibrium within 2 hours due to the adsorption of activated sludge. The process followed first-order kinetic equation, except for dioctyl phthalate (DOP. The factors influencing the adsorption were also evaluated and it was found that higher initial concentrations of PAEs enhanced the removal but affected little the adsorption equilibrium time. The adsorption of PAEs favored lower operating temperature (the optimum temperature was approximately 25°C in this research, which could be an exothermic process. Additionally, lower aqueous pH could also benefit the adsorption.

  4. Keynote address: Federal overview of municipal sludge management

    International Nuclear Information System (INIS)

    Hathaway, W.B.

    1979-01-01

    The proper disposal of sewage sludge is becoming an increasing problem on solid waste management systems throughout the country. Currently 18,000 municipal wastewater treatment plants are generating about 5 million tons of sludge a year. This is expected to double in the next 8 to 10 years. The environmental aspects of sludge disposal are discussed

  5. Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece

    Energy Technology Data Exchange (ETDEWEB)

    Samolada, M.C. [Dept. Secretariat of Environmental and Urban Planning – Decentralized Area Macedonian Thrace, Taki Oikonomidi 1, 54008 Thessaloniki (Greece); Zabaniotou, A.A., E-mail: azampani@auth.gr [Aristotle University of Thessaloniki, Dept. of Chemical Engineering, University Box 455, University Campus, 541 24 Thessaloniki (Greece)

    2014-02-15

    Highlights: • The high output of MSS highlights the need for alternative routes of valorization. • Evaluation of 3 sludge-to-energy valorisation methods through SWOT analysis. • Pyrolysis is an energy and material recovery process resulting to ‘zero waste’. • Identification of challenges and barriers for MSS pyrolysis in Greece was investigated. • Adopters of pyrolysis systems face the challenge of finding new product markets. - Abstract: For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated.

  6. Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece

    International Nuclear Information System (INIS)

    Samolada, M.C.; Zabaniotou, A.A.

    2014-01-01

    Highlights: • The high output of MSS highlights the need for alternative routes of valorization. • Evaluation of 3 sludge-to-energy valorisation methods through SWOT analysis. • Pyrolysis is an energy and material recovery process resulting to ‘zero waste’. • Identification of challenges and barriers for MSS pyrolysis in Greece was investigated. • Adopters of pyrolysis systems face the challenge of finding new product markets. - Abstract: For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated

  7. Dissinfection of municipal sludge and wastewater by energized electrons

    International Nuclear Information System (INIS)

    Trump, J.G.; Wright, K.A.; Sinskey, A.J.; Shah, D.N.; Fernald, R.

    1979-01-01

    Laboratory studies at M.I.T. and high flow rate studies at the M.D.C. Deer Island Wastewater Treatment Plant in Boston have shown the practicality and cost effectiveness of disinfecting liquid municipal sludges by injecting energized electrons. A dosage of 400 Kilorads (4 Kilograys) reduces gram-negative bacteria, including coliforms, fecal coliforms, salmonellae and shigellae, in primary raw or anaerobically digested sludges to undetectable levels. Enteric viruses are reduced by one to two orders of magnitude. This treatment also destroys parasite eggs or renders them non-infectious. Model system studies indicate that trace toxic compounds such as PCBs in water are degraded. The estimated cost of sludge disinfection by electron treatment is about $0.80 per liquid tonne for modular systems of 650 liquid tonnes per day capacity. About 6 Kilowatt-hours of input electric power per tonne is required. The temperature rise of the disinfected watery sludge is about 2 0 C. Electron disinfection combined with subsurface soil injection offers an environmentally attractive, energy-efficient, and economic two -step process for land disposal of municipal sludges with water conservation and soil improvement benefits. Combined with widely-distributed ocean feeding, electron disinfection of the municipal sludge of coastal communities offers a safe marine nutrient for increasing fish population in treated ocean areas. The electron disinfection of effluent wastewater, in lieu of chlorination, is a future application which avoids the production of potentially toxic chlorinated hydrocarbons. (Author) [pt

  8. Assessing potential health effects from municipal sludge incinerators: screening methodology

    Energy Technology Data Exchange (ETDEWEB)

    Fradkin, L.; Bruins, J.F.; Lutkenhoff, S.D.; Stara, J.F.; Lomnitz, E.; Rubin, A.

    1987-04-01

    This paper describes a risk assessment methodology for preliminary assessment of municipal sludge incineration. The methodology is a valuable tool in that it can be used for determining the hazard indices of chemical contaminants that might be present in sewage sludge used in incineration. The paper examines source characteristics (i.e., facility design), atmospheric dispersion of emission, and resulting human exposure and risk from sludge incinerators. Seven of the ten organics were screened for further investigation. An example of the calculations are presented for cadmium.

  9. Rheological characterisation of municipal sludge: a review.

    Science.gov (United States)

    Eshtiaghi, Nicky; Markis, Flora; Yap, Shao Dong; Baudez, Jean-Christophe; Slatter, Paul

    2013-10-01

    Sustainable sludge management is becoming a major issue for wastewater treatment plants due to increasing urban populations and tightening environmental regulations for conventional sludge disposal methods. To address this problem, a good understanding of sludge behaviour is vital to improve and optimize the current state of wastewater treatment operations. This paper provides a review of the recent experimental works in order for researchers to be able to develop a reliable characterization technique for measuring the important properties of sludge such as viscosity, yield stress, thixotropy, and viscoelasticity and to better understand the impact of solids concentrations, temperature, and water content on these properties. In this context, choosing the appropriate rheological model and rheometer is also important. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Vermistabilization of Municipal Wastewater Sludge with Eisenia fetida

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    A Parvaresh, H Movahedian, L Hamidian

    2004-10-01

    Full Text Available Sludges are stabilized to reduce pathogens, eliminate offensive odors and inhibit, reduce or eliminate the potential for putrification. In this study, stabilization of municipal wastewater sludge with and without earthworms (Eisenia fetida was tested in a pilot study. The earthworms were fed at the optimum level of 0.75 kg-feed/kg-worm/day. Decomposition and stabilization of wastewater sludge occurred both in the presence and in the absence of earthworms during 9 weeks but the process was accelerated in their presence. Phosphorus content increased in the sludge with earthworms but decreased in it without them. Nitrogen content in the resulting vermicompost showed no difference with its quantity in the original substrate while it increased in the control treatment.

  11. Soil Microbial Functional and Fungal Diversity as Influenced by Municipal Sewage Sludge Accumulation

    OpenAIRE

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy; Jezierska-Tys, Stefania; Nwaichi, Eucharia Oluchi

    2014-01-01

    Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS) and from a sewage sludge landfill that was 3 m from a SS landfill (SS3) were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Avera...

  12. Use of radiation hygienised municipal sewage sludge as a soil conditioner to enhance agricultural productivity

    International Nuclear Information System (INIS)

    Shah, M.R.; Nareshkumar; Sabharwal, S.

    2009-01-01

    This paper presents a report on the applications that have been developed and demonstrated in the radiation hygienisation of municipal sewage sludge for use in the agriculture as value added manure. Radiation hygienization process effectively eliminates the pathogenic bacteria present in the sewage sludge. Application of sludge to agricultural land enhances the yield and quality of agricultural products due to macronutrients and micronutrients present in the sludge. The process benefits municipal sewage treatment plant authorities as well as farming community. (author)

  13. Recovery of polyhydroxyalkanoates from municipal secondary wastewater sludge.

    Science.gov (United States)

    Kumar, Manish; Ghosh, Pooja; Khosla, Khushboo; Thakur, Indu Shekhar

    2018-05-01

    In the current study, the feasibility of utilizing municipal secondary wastewater sludge for Polyhydroxyalkanoate (PHA) extraction was improved by optimization of various parameters (temperature, duration and concentration of sludge solids). Optimized process parameters resulted in PHA recovery of 0.605 g, significantly higher than un-optimized conditions. The characterization of PHA was carried out by GC-MS, FT-IR and NMR ( 1 H and 13 C) spectroscopy. The PHA profile was found to be dominated by mcl PHA (58%) along with other diverse PHA. The results of the present study show rich diversity of PHA extracted from a raw material which is readily available at minimal cost. In conclusion, exploring the potential of wastes for production of bioplastics not only reduces the cost of bioplastic production, but also provides a sustainable means for waste management. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Sorption of Chromium (VI Using Excess Municipal Sludge

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    Farzaneh Mohammadi

    2014-04-01

    Full Text Available Removing or decreasing hexavalent Chromium from wastewater to the permitted levels is important due to its non-biodegradation, bioaccumulation, cancer-causing and toxic effects. In this study, biosorption of Cr(VI from aqueous solutions by Excess Active Municipal Sludge was investigated as a function of initial Chromium (VI concentration (in the range of 5-90 mg/l, initial pH (in the range of 2-8, agitation speed (in the range of 50-200 rpm, adsorbent dosage (in the range of 2-10 g/l and agitation time (in the range of 5-480 min in a batch system. The optimum conditions were found by full factorial design approach. The results showed that the equilibrium time for adsorbent is 120 minutes. Also, sorption data have a good fitness by Freundlich isotherm model and adsorption kinetic is adopted with pseudo-second order model. In batch studies, at optimum condition (90 mg/l initial concentration, pH 2, agitation speed 200 rpm and adsorbent dosage 4 g/l, the adsorption performance was about 96%; the maximum adsorption capacity was calculated about 41.69 mg of Cr/g of adsorbent. Overall, it can be concluded that Excess Active Municipal Sludge, has a good performance as a biological, biodegradable, abundant and low-cost adsorbent for the removal of Cr (VI from aqueous solutions.

  15. European municipalities and the liberalized energy market

    International Nuclear Information System (INIS)

    2002-04-01

    Municipalities are directly affected by the liberalization of the energy markets. Because they all consume or even produce energy, whether it be for their own consumption or to resell it, they often distribute gas, electricity or heat, they plan urban areas and organize the energy networks on their territory, while in addition citizens expect municipalities to inform them and even protect them against the possible excesses of energy salesmen. Elected representatives administrations, local agencies, municipal companies, citizens' associations etc., all have to innovate. This supplement to Energie-Cites INFO is intended to provide you with practical information and further analyses of the liberalization process. (authors)

  16. Types, risks and market of municipal bonds

    Directory of Open Access Journals (Sweden)

    Grujić Miloš

    2012-01-01

    Full Text Available Municipal bonds are issued by cities, municipalities or other local communities in order to quickly raise funds to cover current budget deficits, finish infrastructure projects for production and distribution of thermal energy, improve water supply, road construction, sports and recreation centers, schools or to fund such projects on more favorable terms than to borrow from banks. In this manner, necessary conditions are created for faster development of the real sector. The aim of this study is to evaluate the importance, possibilities and effects of the bond issue in the Republika Srpska aimed at securing funding for and development of local communities. Good examples that local government bonds enhance community development include capital markets in countries that have made the transition from the socialist system design, similar to the market of the Republika Srpska, like the Polish, Slovakian, Hungarian and Croatian markets. Issues of municipal bonds in the Republika Srpska succeeded mostly due to the workings of Investment-Development Bank of RS. However, it certainly shows that further high-quality municipal bonds could attract more interest from various institutional investors, especially mutual funds and insurance companies, and investors who are more risk-averse will be able to familiarize and inform themselves with the functioning of capital markets. In this manner, our capital market would confirm its essential role and thus become a generator of overall economic development of the Republika Srpska because it would enable more efficient collection and allocation of capital resources.

  17. Modern disposal techniques for sewage sludge and municipal waste; Moderne Entsorgungsverfahren fuer Klaerschlamm und Hausmuell

    Energy Technology Data Exchange (ETDEWEB)

    Garlipp, G. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany); Maczek, K. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany); Steinkamp, H. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany)

    1996-05-01

    Since the passing of the technical code on municipal waste, the issue of the disposal of sewage sludge and municipal waste has become more and more important in Germany. Increasingly, the possibility is made use of to burn industrial and municipal sewage sludge and municipal waste. For such thermal disposal, a great number of techniques are nowadays available. (orig.) [Deutsch] Seit der Verabschiedung der TA Siedlungsabfall gewinnt die Problematik der Entsorgung von Klaerschlamm und Hausmuell in Deutschland zunehmend an Bedeutung. Von der Moeglichkeit, industrielle und kommunale Klaerschlaemme und Hausmuell zu verbrennen, wird in zunehmendem Masse Gebrauch gemacht. Zur thermischen Entsorgung von Klaerschlaemmen und Hausmuell stehen heute eine Vielzahl von Verfahren zur Verfuegung. (orig.)

  18. Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece.

    Science.gov (United States)

    Samolada, M C; Zabaniotou, A A

    2014-02-01

    For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a 'zero waste' solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Use of Municipal Sewage Sludge for Improvement of Forest Sites in the Southeast

    Science.gov (United States)

    Charles R. Berry

    1987-01-01

    In eight field experiments dried municipal sewage sludge was applied to forest sites before planting of seedlings. In all cases, tree growth was faster on sludge-amended plots than on plots that received fertilizer and lime or no amendment. Deep subsoiling was beneficial regardless of Soil amendment. Where weeds were plentiful at the outset, they became serious...

  20. Thermo-Oxidization of Municipal Wastewater Treatment Plant Sludge for Production of Class A Biosolids

    Science.gov (United States)

    Bench-scale reactors were used to test a novel thermo-oxidation process on municipal wastewater treatment plant (WWTP) waste activated sludge (WAS) using hydrogen peroxide (H2O2) to achieve a Class A sludge product appropriate for land application. Reactor ...

  1. Co-Combustion of Municipal Sewage Sludge and Hard Coal on Fluidized Bed Boiler WF-6

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    Rajczyk Rafał

    2014-12-01

    Full Text Available According to data of the Central Statistical Office, the amount of sludge produced in municipal wastewater treatment plants in 2010 amounted to 526000 Mg d.m. The forecast of municipal sewage sludge amount in 2015 according to KPGO2014 will reach 642400 Mg d.m. and is expected to increase in subsequent years. Significant amounts of sludge will create problems due to its utilization. In order to solve this problem the use of thermal methods for sludge utilization is expected. According to the National Waste Management Plan nearly 30% of sewage sludge mass should be thermally utilized by 2022. The article presents the results of co-combustion of coal and municipal sewage sludge in a bubbling fluidized bed boiler made by SEFAKO and located in the Municipal Heating Company in Morag. Four tests of hard coal and sewage sludge co-combustion have been conducted. Boiler performance, emissions and ash quality were investigated.

  2. Municipal Sewage Sludge Drying Treatment by an Composite Modifier

    OpenAIRE

    Na Wei

    2012-01-01

    A sludge composite modifier (SCM) which comprises a mixture of three cementitious components was proposed for sludge drying and stabilization. Effect of SCM components on sludge moisture content was analyzed using uniform design and the optimum composition of SCM was determined by computer-aided modeling and optimization. To compare the drying effect of SCM, quicklime, and Portland cement, the effects of material content and curing time on moisture content of sludge were also studied. The res...

  3. [Effect of different sludge retention time (SRT) on municipal sewage sludge bioleaching continuous plug flow reaction system].

    Science.gov (United States)

    Liu, Fen-Wu; Zhou, Li-Xiang; Zhou, Jun; Jiang, Feng; Wang, Dian-Zhan

    2012-01-01

    A plug-flow bio-reactor of 700 L working volume for sludge bioleaching was used in this study. The reactor was divided into six sections along the direction of the sludge movement. Fourteen days of continuous operation of sludge bioleaching with different sludge retention time (SRT) under the condition of 1.2 m3 x h(-1) aeration amount and 4 g x L(-1) of microbial nutritional substance was conducted. During sludge bioleaching, the dynamic changes of pH, DO, dewaterability (specific resistance to filtration, SRF) of sewage sludge in different sections were investigated in the present study. The results showed that sludge pH were maintained at 5.00, 3.00, 2.90, 2.70, 2.60 and 2.40 from section 1 to section 6 and the SRF of sludge was drastically decreased from initial 0.64 x 10(13) m x kg(-1) to the final 0.33 x 10(13) m x kg(-1) when bioleaching system reached stable at hour 72 with SRT 2.5d. In addition, the sludge pH were maintained at 5.10, 4.10, 3.20, 2.90, 2.70 and 2.60, the DO value were 0.43, 1.47, 3.29, 4.76, 5.75 and 5.88 mg x L(-1) from section 1 to section 6, and the SRF of sludge was drastically decreased from initial 0.56 x 10(13) to the final 0.20 x 10(13) m x kg(-1) when bioleaching system reached stable at hour 120 with SRT 2 d. The pH value was increased to 3.00 at section 6 at hour 48 h with SRT 1.25 d. The bioleaching system imbalanced in this operation conditions because of the utilization efficiency of microbial nutritional substance by Acidibacillus spp. was decreased. The longer sludge retention time, the easier bioleaching system reached stable. 2 d could be used as the optimum sludge retention time in engineering application. The bioleached sludge was collected and dewatered by plate-and-frame filter press to the moisture content of dewatered sludge cake under 60%. This study would provide the necessary data to the engineering application on municipal sewage sludge bioleaching.

  4. Use of Municipal Sewage Sludge for Improvement of Forest Sites in the Southeast

    Energy Technology Data Exchange (ETDEWEB)

    Charles R. Berry

    1987-09-01

    In eight field experiments dried municipal sewage sludge was applied to forest sites before planting of seedlings. In all cases, tree growth was faster on sludge-amended plots than on plots that received fertilizer and lime or no amendment. In all studies, concentrations of total nitrogen in the soil were higher on sludge plots than on control or fertilizer plots, even on good forest sites. In seven of the eight studies, concentrations of phosphorus also were higher on sludge plots than on control or fertilizer plots. Nitrogen and phosphorus tended to be higher in foliage from trees growing on sludge plots. Deep subsoiling was beneficial regardless of soil amendment. Where weeds were plentiful at the outset, they became serious competitors on plots receiving sludge.

  5. Soil Microbial Functional and Fungal Diversity as Influenced by Municipal Sewage Sludge Accumulation

    Directory of Open Access Journals (Sweden)

    Magdalena Frąc

    2014-08-01

    Full Text Available Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS and from a sewage sludge landfill that was 3 m from a SS landfill (SS3 were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Average Well Color Development (AWCD, Richness (R and Shannon-Weaver index (H were calculated to interpret the results. The fungi isolated from the sewage sludge were identified using comparative rDNA sequencing of the LSU D2 region. The MicroSEQ® ID software was used to assess the raw sequence files, perform sequence matching to the MicroSEQ® ID-validated reference database and create Neighbor-Joining trees. Moreover, the genera of fungi isolated from the soil were identified using microscopic methods. Municipal sewage sludge can serve as a habitat for plant pathogens and as a source of pathogen strains for biotechnological applications.

  6. Soil microbial functional and fungal diversity as influenced by municipal sewage sludge accumulation.

    Science.gov (United States)

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy; Jezierska-Tys, Stefania; Nwaichi, Eucharia Oluchi

    2014-08-28

    Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS) and from a sewage sludge landfill that was 3 m from a SS landfill (SS3) were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H) were calculated to interpret the results. The fungi isolated from the sewage sludge were identified using comparative rDNA sequencing of the LSU D2 region. The MicroSEQ® ID software was used to assess the raw sequence files, perform sequence matching to the MicroSEQ® ID-validated reference database and create Neighbor-Joining trees. Moreover, the genera of fungi isolated from the soil were identified using microscopic methods. Municipal sewage sludge can serve as a habitat for plant pathogens and as a source of pathogen strains for biotechnological applications.

  7. Soil Microbial Functional and Fungal Diversity as Influenced by Municipal Sewage Sludge Accumulation

    Science.gov (United States)

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy; Jezierska-Tys, Stefania; Nwaichi, Eucharia Oluchi

    2014-01-01

    Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS) and from a sewage sludge landfill that was 3 m from a SS landfill (SS3) were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H) were calculated to interpret the results. The fungi isolated from the sewage sludge were identified using comparative rDNA sequencing of the LSU D2 region. The MicroSEQ® ID software was used to assess the raw sequence files, perform sequence matching to the MicroSEQ® ID-validated reference database and create Neighbor-Joining trees. Moreover, the genera of fungi isolated from the soil were identified using microscopic methods. Municipal sewage sludge can serve as a habitat for plant pathogens and as a source of pathogen strains for biotechnological applications. PMID:25170681

  8. Two strategies for phosphorus removal from reject water of municipal wastewater treatment plant using alum sludge.

    Science.gov (United States)

    Yang, Y; Zhao, Y Q; Babatunde, A O; Kearney, P

    2009-01-01

    In view of the well recognized need of reject water treatment in MWWTP (municipal wastewater treatment plant), this paper outlines two strategies for P removal from reject water using alum sludge, which is produced as by-product in drinking water treatment plant when aluminium sulphate is used for flocculating raw waters. One strategy is the use of the alum sludge in liquid form for co-conditioning and dewatering with the anaerobically digested activated sludge in MWWTP. The other strategy involves the use of the dewatered alum sludge cakes in a fixed bed for P immobilization from the reject water that refers to the mixture of the supernatant of the sludge thickening process and the supernatant of the anaerobically digested sludge. Experimental trials have demonstrated that the alum sludge can efficiently reduce P level in reject water. The co-conditioning strategy could reduce P from 597-675 mg P/L to 0.14-3.20 mg P/L in the supernatant of the sewage sludge while the organic polymer dosage for the conditioning of the mixed sludges would also be significantly reduced. The second strategy of reject water filtration with alum sludge bed has shown a good performance of P reduction. The alum sludge has P-adsorption capacity of 31 mg-P/g-sludge, which was tested under filtration velocity of 1.0 m/h. The two strategies highlight the beneficial utilization of alum sludge in wastewater treatment process in MWWTP, thus converting the alum sludge as a useful material, rather than a waste for landfill.

  9. From municipal/industrial wastewater sludge and FOG to fertilizer: A proposal for economic sustainable sludge management.

    Science.gov (United States)

    Bratina, Božidar; Šorgo, Andrej; Kramberger, Janez; Ajdnik, Urban; Zemljič, Lidija Fras; Ekart, Janez; Šafarič, Riko

    2016-12-01

    After a ban on the depositing of untreated sludge in landfills, the sludge from municipal and industrial water-treatment plants can be regarded as a problem. Waste products of the water treatment process can be a problem or an opportunity - a source for obtaining raw materials. In the European Union, raw sludge and fats, oil and grease (FOG) from municipal and industrial wastewater treatment plants (WWTP) cannot be deposited in any natural or controlled environment. For this reason, it must be processed (stabilized, dried) to be used later as a fertilizer, building material, or alternative fuel source suitable for co-incineration in high temperature furnaces (power plants or concrete plants). The processes of drying sludge, where heat and electricity are used, are energy consuming and economically unattractive. Beside energy efficiency, the main problem of sludge drying is in its variability of quality as a raw material. In addition to this, sludge can be contaminated by a number of organic and inorganic pollutants and organisms. Due to the presence or absence of pollutants, different end products can be economically interesting. For example, if the dried sludge contains coliform bacteria, viruses, helminths eggs or smaller quantities of heavy metals, it cannot be used as a fertilizer but can still be used as a fuel. The objectives of the current article is to present a batch-processing pilot device of sludge or digestate that allows the following: (1) low pressure and low temperature energy effective drying of from 10 to 40% remaining water content, (2) disinfection of pathogen (micro)organisms, (3) heavy metal reduction, (4) production of products of predetermined quality (e.g. containing different quantities of water; it can be used as a fertilizer, or if the percentage of water in the dry sludge is decreased to 10%, then the dried sludge can be used as a fuel with a calorific value similar to coal). An important feature is also the utilization of low

  10. Fertilization value of municipal sewage sludge for Eucalyptus camaldulensis plants

    Directory of Open Access Journals (Sweden)

    Soudani Leila

    2017-03-01

    Full Text Available The wastewater treatment produces a large amount of sludge. The different uses of eliminations sludge such as landfills or incineration have consequences negative for the environment, the agricultural use has increased worldwide, especially in crops and few or no studies have been conducted with forest plantations in Algeria. The objective of this study is to assess fertilizing characteristics of the sludge from the wastewater treatment plant of Tiaret (Algeria. One-year-old saplings of Eucalyptus camaldulensis were transplanted into pots with sludge/soil mixtures where sludge content was 20%, 40% and 60%. Biometric measurements (height, base diameter, diameter at mid-height and the number of leaves were performed during six months after planting. Results demonstrated the positive effect of sludge application. A significant difference in height increment and number of leaves was found between the control and sludge-treated plants. Biometric values for all sludge mixtures were higher than those for control plants (100% soil. The mixture, which contained 60% sludge, gives the best result, except for a diameter of stem. Plants grown on sludge/soil mixture had average height 49.4 ± 24.1 cm and average number of leaves 68.8 ± 6.2 while average height for plants grown on soil was 34.3 ± 12.8 cm and average number of leaves was 40 ± 3.8. Sludge application provides soil amendment and additional nutrient supply for planted trees.

  11. Municipal sludge as source of nitrogen and phosphorus in perennial ...

    African Journals Online (AJOL)

    Land application of sludge has been shown to improve soil properties and aid crop growth, but the possibility of constituent nutrients such as nitrogen and phosphorus reaching environmentally toxic levels has caused governing authorities to set limits to how much sludge can be applied to agronomic land. The high nitrogen ...

  12. Screening methodology for assessing potential health effects from municipal sludge incinerators

    Energy Technology Data Exchange (ETDEWEB)

    Fradkin, L.; Bruins, R.J.F.; Lutkenhoff, S.D.; Stara, J.F.; Lomnitz, E.

    1987-01-01

    This paper describes a risk assessment methodology for preliminary assessment of municipal sludge incineration. The methodology is a valuable tool in that it can be used for determining the hazard indices of chemical contaminants that might be present in sewage sludge used in incineration. The paper examines source characteristics (i.e., facility design), atmospheric dispersion of emission, and resulting human exposure and risk from sludge incinerators. Seven of the ten organics were screened for further investigation. An example of the calculations are presented for cadmium.

  13. Screening methodology for assessing potential health effects from municipal sludge incinerators

    Energy Technology Data Exchange (ETDEWEB)

    Fradkin, L.; Bruins, R.J.F.; Lutkenhoff, S.D.; Stara, J.F.; Lomnitz, E.; Rubin, A.

    1987-04-01

    This paper describes a risk assessment of methodology for preliminary assessment of municipal sludge incineration. The methodology is a valuable tool in that it can be used for determining the hazard indices of chemical contaminants that might be present in sewage sludge used in incineration. The paper examines source characteristics (i.e. facility design), atmospheric dispersion of emission, and resulting human exposure and risk from sludge incinerators. Seven of the ten organics were screened for further investigation. An example of the calculations are presented for cadmium. (Refs. 5).

  14. Economic comparison of sludge irradiation and alternative methods of municipal sludge treatment

    International Nuclear Information System (INIS)

    Ahlstrom, S.B.; McGuire, H.E.

    1977-11-01

    The relative economics of radiation treatment and other sludge treatment processes are reported. The desirability of radiation treatment is assessed in terms of cost and the quality of the treated sludge product. The major conclusions of this study are: radiation treatment is a high-level disinfection process. Therefore, it should only be considered if high levels of disinfection are required for widespread reuse of the sludge; the handling, transporting and pathogen growback problems associated with disinfected wet sludge makes it less attractive for reuse than dry sludge; radiation of composted sludge produces a product of similar quality at less cost than any thermal treatment and/or flash drying treatment option for situations where a high degree of disinfection is required; and heavy metal concerns, especially cadmium, may limit the reuse of sludge despite high disinfection levels. It is recommended that radiation treatment of sludge, particularly dry sludge, continue to be studied. A sensitivity analysis investigating the optimal conditions under which sludge irradiation operates should be instigated. Furthermore, costs of adding sludge irradiation to existing sludge treatment schemes should be determined

  15. An Economic comparison of sludge irradiation and alternative methods of municipal sludge treatment

    Energy Technology Data Exchange (ETDEWEB)

    Ahlstrom, S.B.; McGuire, H.E.

    1977-11-01

    The relative economics of radiation treatment and other sludge treatment processes are reported. The desirability of radiation treatment is assessed in terms of cost and the quality of the treated sludge product. The major conclusions of this study are: radiation treatment is a high-level disinfection process. Therefore, it should only be considered if high levels of disinfection are required for widespread reuse of the sludge; the handling, transporting and pathogen growback problems associated with disinfected wet sludge makes it less attractive for reuse than dry sludge; radiation of composted sludge produces a product of similar quality at less cost than any thermal treatment and/or flash drying treatment option for situations where a high degree of disinfection is required; and heavy metal concerns, especially cadmium, may limit the reuse of sludge despite high disinfection levels. It is recommended that radiation treatment of sludge, particularly dry sludge, continue to be studied. A sensitivity analysis investigating the optimal conditions under which sludge irradiation operates should be instigated. Furthermore, costs of adding sludge irradiation to existing sludge treatment schemes should be determined.

  16. The use of municipal sewage sludge for the stabilization of soil contaminated by mining activities.

    Science.gov (United States)

    Theodoratos, P; Moirou, A; Xenidis, A; Paspaliaris, I

    2000-10-02

    The ability of municipal sewage sludge to immobilize Pb, Zn and Cd contained in contaminated soil originating from a former mining area in Lavrion, Greece was investigated. The soil was cured with sewage sludge in various proportions. The stabilization was evaluated primarily by applying chemical tests and complemented by the performance of additional biological tests. Application of the U.S. EPA Toxicity Characteristic Leaching Procedure (TCLP) on the stabilized mixtures proved that Pb, Zn and Cd solubility was reduced by 84%, 64% and 76%, respectively, at 15% w/w sludge addition, while a 10% w/w addition was sufficient to reduce Pb solubility below the U.S. EPA TCLP regulatory limit. The results of the extraction using EDTA solution showed the same trend, resulting in 26%, 36% and 53% reduction in the Pb, Zn and Cd extractable fractions, respectively. Speciation analysis of the treated soils revealed a significant decrease in the mobile fractions of heavy metals, which was attributed to their retention in sewage sludge by adsorption and organic complexation mechanisms. For the assessment of possible phytotoxicity, experiments including growing dwarf beans in the treated soil was carried out. It was found that sewage sludge addition had a positive effect on plant growth. Furthermore, the Pb and Zn uptake of plant leaves and roots was reduced, while Cd uptake was unaffected by the sludge treatment. The results of this study support the hypothesis that municipal sewage sludge is a potential effective stabilizing agent for contaminated soil containing Pb, Zn and Cd.

  17. Municipal Sewage Sludge Drying Treatment by an Composite Modifier

    Directory of Open Access Journals (Sweden)

    Na Wei

    2012-01-01

    Full Text Available A sludge composite modifier (SCM which comprises a mixture of three cementitious components was proposed for sludge drying and stabilization. Effect of SCM components on sludge moisture content was analyzed using uniform design and the optimum composition of SCM was determined by computer-aided modeling and optimization. To compare the drying effect of SCM, quicklime, and Portland cement, the effects of material content and curing time on moisture content of sludge were also studied. The results showed that the optimum ratio of modifier component was slag/cement clinker/dihydrate gypsum = 0.64/0.292/0.068 and the moisture content of SCM-stabilized sludge decreased with the increasing material content and extending curing time. Besides, the experimental results showed that optimized SCM behaved better than quicklime and Portland cement in sludge semi-drying and XRD analysis revealed that the main hydrated product of stabilization was ettringite, which played an important role in the effective drying process. Sewage sludge stabilized using SCM could be used as an effective landfill cover.

  18. The use of reed canary grass and giant miscanthus in the phytoremediation of municipal sewage sludge.

    Science.gov (United States)

    Antonkiewicz, Jacek; Kołodziej, Barbara; Bielińska, Elżbieta Jolanta

    2016-05-01

    The application of municipal sewage sludge on energy crops is an alternative form of recycling nutrients, food materials, and organic matter from waste. Municipal sewage sludge constitutes a potential source of heavy metals in soil, which can be partially removed by the cultivation of energy crops. The aim of the research was to assess the effect of municipal sewage sludge on the uptake of heavy metals by monocotyledonous energy crops. Sewage sludge was applied at doses of 0, 10, 20, 40, and 60 Mg DM · ha(-1) once, before the sowing of plants. In a 6-year field experiment, the effect of four levels of fertilisation with sewage sludge on the uptake of heavy metals by two species of energy crops, reed canary grass (Phalaris arundinacea L.) of 'Bamse' cultivar and giant miscanthus (Miscanthus × giganteus GREEF et DEU), was analysed. It was established that the increasing doses of sewage sludge had a considerable effect on the increase in biomass yield from the tested plants. Due to the increasing doses of sewage sludge, a significant increase in heavy metals content in the energy crops was recorded. The heavy metal uptake with the miscanthus yield was the highest at a dose of 20 Mg DM · ha(-1), and at a dose of 40 Mg DM · ha(-1) in the case of reed canary grass. Research results indicate that on account of higher yields, higher bioaccumulation, and higher heavy metal uptake, miscanthus can be selected for the remediation of sewage sludge.

  19. Potential investigation of Reusing Ardabil Municipal Wastewater Treatment Plant Sludge Based on AHP and TOPSIS Models

    Directory of Open Access Journals (Sweden)

    Bizhan Maghsoudlou Kamali

    2013-07-01

    Full Text Available Introduction :By ever-increasing of population, shortage of water resources and the necessity of wastewater treatment, huge volumes of sludge that is a byproduct of wastewater treatment, requires to be disposed in environmentally secure ways. The target of specifying strategic preferences of reuse of sludge has been to find the correct way of disposal or beneficial use of sludge. Material and methods: In this study, to select the best alternative for reuse of wastewater sludge two systematic methods are introduced, which four alternatives for reuse of sludge (use in agriculture, use in green space, biogas, desert combat are introduced and they are compared by four main parameters including: 1- physicochemical 2-biological 3 - economic, social and cultural, and 4 - environmental pollution situation, that each contains some criteria. In this study, first each of the related parameters and criteria are compared by the expert groups of and through questionnaire. Then these weights are entered into Expert Choice software for the analyze of AHP model and paired comparisons and weightings have been done on the related parameters and criteria. Ultimately, the output of the software is entered into TOPSIS software for the analyze of TOPSIS model until the best alternative is selected. Results: sludge of Ardabil municipal wastewater treatment plant, according to standards and EPA regulations is eligible to class B, and due to the chemical in terms of heavy metals have special (excellent quality and contains considerable quantities of organic substance, nutrients and micronutrients which indicates the fertilizer value of the sludge. Conclusion: The result of this comparison has shown that the application of sludge in green spaces is the most appropriate alternative and then use in agriculture, biogas alternative, and desert combat alternative are, respectively, placed in the second to fourth preference for the reuse of sludge derived from municipal

  20. Mesophilic anaerobic co-digestion of municipal solid waste and sewage sludge

    DEFF Research Database (Denmark)

    Aghdam, Ehsan Fathi; Kinnunen, V.; Rintala, Jukka A.

    2015-01-01

    This paper presents mesophilic anaerobic digestion (AD) of organic fraction of municipal solid waste (OFMSW), biowaste (BW), sewage sludge (SS), and co-digestion of BW and SS. Average methane yields of 386 ± 54, 385 ± 82, 198 ± 14, and 318 ± 59 L CH4/kg volatile solids (VS) were obtained for OFMSW...

  1. Effects of municipal sewage sludge doses on the yield, some yield ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-09-03

    Sep 3, 2008 ... Whereas grain yield, which was the highest component was ... land application, many studies have been performed ... grain. Analysis of variance was used to compare treatment ... een 17.0 - 164.0 cm depending on the environmental .... municipal sewage sludge for the stabilization of soil contaminated by.

  2. Acid fermentation of municipal sludge: the effect of sludge type and origin on the production and composition of volatile fatty acids

    International Nuclear Information System (INIS)

    Ucisik, A. S.; Schmidit, J. E.; Henze, M.

    2009-01-01

    Due to the more stringent legislations controlling discharges of wastewater treatment plants (WWTPs) and existing problems such as high sludge production, new wastewater treatment processes resulting in considerably reduced sludge production and more effective treatment would be of great value. In this study, the feasibility of implementing acid fermentation process on different types of municipal sludge to increase soluble chemical oxygen demand (SCOD), especially short-chain volatile fatty acids (VFAs) was investigated by batch and semi-continuous experiments. (Author)

  3. Review of municipal sludge use as a soil amendment on disturbed lands

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Hendrickson, P.L.

    1990-08-01

    The US Department of Energy is examining options of improving soil conditions at Hanford reclamation sites. One promising technology is the incorporation of municipal sewage sludge into the soil profile. This report reviews the potential benefits and adverse consequences of sludge use in land reclamation. Land reclamation comprises those activities instigated to return a mechanically disturbed site to some later successional state. Besides the introduction of suitable plant species to disturbed lands, reclamation generally requires measures to enhance long-term soil nutrient content, moisture retention or drainage, and mitigation of toxic effects from metals and pH. One of the more effective means of remediating adverse soil characteristics is the application of complex organic manures such as municipal sewage sludge. Sewage sludges contain complete macro- and micronutrients necessary to sustain plant growth. The application of sewage sludge may reestablish microbial activity in sterile soils. Physical properties, such as water-holding capacity and percentage water-stable aggregates, also improve with the addition of sewage sludge. Sludge applications may also increase the rate of degradation of some hydrocarbon pollutants in soils. Potential adverse impacts associated with the application of sewage sludge to land include negative public perception of human waste products; concerns regarding pathogen buildup and spread in the soils, plants, and water; entrance and accumulation of heavy metals in the food chain; salt accumulation in the soil and ground water; leaching of nitrates into ground water; and accumulation of other potentially toxic substances, such as boron and synthetic hydrocarbons, in the soil, plants, and food chain. 56 refs., 10 tabs.

  4. Phytoextraction of heavy metals from municipal sewage sludge by Rosa multiflora and Sida hermaphrodita.

    Science.gov (United States)

    Antonkiewicz, Jacek; Kołodziej, Barbara; Bielińska, Elżbieta Jolanta

    2017-04-03

    The aim of the study was to evaluate the efficacy of the multiflora rose var. "Jatar" (Rosa multiflora Thunb. ex Murray) and the Virginia fanpetals (Sida hermaphrodita Rusby) to phytoextract heavy metals from municipal sewage sludge. The 6-year field experiment involved four levels of fertilization with sewage sludge at doses of 0, 10, 20, 40, and 60 Mg DM (Dry Mass) sludge ha -1 . The increasing doses of sewage sludge were found to significantly increase the yield of multiflora rose and Virginia fanpetals biomass. They also significantly increased the content of heavy metals in these plants. The highest uptake of heavy metals by the multiflora rose and Virginia fanpetals crops was recorded at the fertilization dose of 60 Mg DM ⋅ ha -1 . Our investigations show that the Virginia fanpetals was more efficient in the phytoextraction of Cr, Ni, Cu, Zn, and Cd from the sewage sludge than the multiflora rose, due to the greater yields and higher heavy metal uptake by the former plant. In turn, the multiflora rose phytoextracted greater amounts of Pb from the sewage sludge. The analyses indicate that the Virginia fanpetals can be used for phytoremediation (phytoextraction) of heavy metals contained in sewage sludge.

  5. Thermogravimetric analysis of the co-pyrolysis of paper sludge and municipal solid waste

    International Nuclear Information System (INIS)

    Fang, Shiwen; Yu, Zhaosheng; Lin, Yousheng; Hu, Shanchao; Liao, Yanfen; Ma, Xiaoqian

    2015-01-01

    Highlights: • The co-pyrolysis of municipal solid waste, paper sludge and the blends was studied. • The reactivity of paper sludge could be improved by blending municipal solid waste. • The FWO and KAS methods were used to calculate activation energy. • The average activation energy was the minimum by blending 50% paper sludge. - Abstract: The pyrolysis characteristics of municipal solid waste (MSW), paper sludge (PS) and their blends were studied through a thermogravimetric simultaneous thermal analyzer from room temperature to 1000 °C. Meanwhile their kinetics were studied by Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) methods. The mass proportions of PS in the blends were 10%, 30%, 50%, 70%, 90%, respectively and the experiments were carried out at different heating rates (30, 40 and 50 °C/min). The initial temperature of MSW was lower than that of PS and the terminated temperature was higher than PS. The comprehensive characteristic index decreased progressively along with the decrease of the MSW proportion. The values of average activation energies calculated by FWO and KAS methods were highly consistent. The average activation energy reached the minimum number, 96.7 kJ/mol by KAS and 11.56 kJ/mol by FWO, with the proportion of PS was 50%

  6. Treatment of winery wastewater in a conventional municipal activated sludge process: five years of experience.

    Science.gov (United States)

    Bolzonella, D; Zanette, M; Battistoni, P; Cecchi, F

    2007-01-01

    A full-scale wastewater treatment plant where municipal and winery wastewaters were co-treated was studied for five years. The experimental results showed that suspended solids, COD, nitrogen and phosphorous were effectively removed both during the treatment of municipal wastewater and the cotreatment of municipal and winery wastewater. The sludge production increase from 4 tons to 5.5 tons per day during the harvesting and wine making period. In any case the specific sludge production was 0.2 kgMLVSS per kgCOD(removed) despite the organic loading increasing. About 70% of the COD was removed through respiration. Also the energy demand increased from 6,000 to 7,000 kWh per day. The estimated costs for the treatment of the winery wastewater was 0.2-0.3 Euros per m3 of treated wastewater. With reference to the process efficiency, the nitrogen removal was just 20%. The co-treatment of municipal and winery wastewater in conventional activated sludge processes can be a feasible solution for the treatment of these streams at relatively low costs.

  7. Co-digestion of municipal sludge and external organic wastes for enhanced biogas production under realistic plant constraints.

    Science.gov (United States)

    Tandukar, Madan; Pavlostathis, Spyros G

    2015-12-15

    A bench-scale investigation was conducted to select external organic wastes and mixing ratios for co-digestion with municipal sludge at the F. Wayne Hill Water Resources Center (FWHWRC), Gwinnett County, GA, USA to support a combined heat and power (CHP) project. External wastes were chosen and used subject to two constraints: a) digester retention time no lower than 15 d; and b) total biogas (methane) production not to exceed a specific target level based on air permit constraints on CO2 emissions. Primary sludge (PS), thickened waste activated sludge (TWAS) and digested sludge collected at the FWHWRC, industrial liquid waste obtained from a chewing gum manufacturing plant (GW) and dewatered fat-oil-grease (FOG) were used. All sludge and waste samples were characterized and their ultimate digestibility was assessed at 35 °C. The ultimate COD to methane conversion of PS, TWAS, municipal sludge (PS + TWAS; 40:60 w/w TS basis), GW and FOG was 49.2, 35.2, 40.3, 72.7, and 81.1%, respectively. Co-digestion of municipal sludge with GW, FOG or both, was evaluated using four bench-scale, mesophilic (35 °C) digesters. Biogas production increased significantly and additional degradation of the municipal sludge between 1.1 and 30.7% was observed. Biogas and methane production was very close to the target levels necessary to close the energy deficit at the FWHWRC. Co-digestion resulted in an effluent quality similar to that of the control digester fed only with the municipal sludge, indicating that co-digestion had no adverse effects. Study results prove that high methane production is achievable with the addition of concentrated external organic wastes to municipal digesters, at acceptable higher digester organic loadings and lower retention times, allowing the effective implementation of CHP programs at municipal wastewater treatment plants, with significant cost savings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Chitosan use in chemical conditioning for dewatering municipal-activated sludge.

    Science.gov (United States)

    Zemmouri, H; Mameri, N; Lounici, H

    2015-01-01

    This work aims to evaluate the potential use of chitosan as an eco-friendly flocculant in chemical conditioning of municipal-activated sludge. Chitosan effectiveness was compared with synthetic cationic polyelectrolyte Sedipur CF802 (Sed CF802) and ferric chloride (FeCl₃). In this context, raw sludge samples from Beni-Messous wastewater treatment plant (WWTP) were tested. The classic jar test method was used to condition sludge samples. Capillary suction time (CST), specific resistance to filtration (SRF), cakes dry solid content and filtrate turbidity were analyzed to determine filterability, dewatering capacity of conditioned sludge and the optimum dose of each conditioner. Data exhibit that chitosan, FeCl₃and Sed CF802 improve sludge dewatering. Optimum dosages of chitosan, Sed CF802 and FeCl₃allowing CST values of 6, 5 and 9 s, were found, respectively, between 2-3, 1.5-3 and 6 kg/t ds. Both polymers have shown faster water removal with more permeable sludge. SRF values were 0.634 × 10¹², 0.932 × 10¹² and 2 × 10¹² m/kg for Sed CF802, chitosan and FeCl₃respectively. A reduction of 94.68 and 87.85% of the filtrate turbidity was obtained with optimal dosage of chitosan and Sed CF802, respectively. In contrast, 54.18% of turbidity abatement has been obtained using optimal dosage of FeCl₃.

  9. Effect of biodegradation on the consolidation properties of a dewatered municipal sewage sludge.

    Science.gov (United States)

    O'Kelly, Brendan C

    2008-01-01

    The effect of biodegradation on the consolidation characteristics of an anaerobically digested, dewatered municipal sewage sludge was studied. Maintained-load oedometer consolidation tests that included measurement of the pore fluid pressure response were conducted on moderately degraded sludge material and saturated bulk samples that had been stored under static conditions and allowed to anaerobically biodegrade further (simulating what would happen in an actual sewage sludge monofill or lagoon condition). Strongly degraded sludge material was produced after a storage period of 13 years at ambient temperatures of 5-15 degrees C, with the total volatile solids reducing from initially 70% to 55%. The sludge materials were highly compressible, although impermeable for practical purposes. Primary consolidation generally occurred very slowly, which was attributed to the microstructure of the solid phase, the composition and viscosity of the pore fluid, ongoing biodegradation and the high organic contents. The coefficient of primary consolidation values decreased from initially about 0.35m2/yr to 0.003-0.03m2/yr with increasing effective stress (sigmav'=3-100kPa). Initially, the strongly degraded sludge material was slightly more permeable, although both the moderately and strongly degraded materials became impermeable for practical purposes (k=10(-9)-10(-12)m/s) below about 650% and 450% water contents, respectively. Secondary compression became more dominant with increasing effective stress with a mean secondary compression index (Calphae) value of 0.9 measured for both the moderately and strongly degraded materials.

  10. Modelling of sludge blanket height and flow pattern in UASB reactors treating municipal wastewater

    International Nuclear Information System (INIS)

    Singh, K.S.; Viraraghavan, T.

    2002-01-01

    Two upflow anaerobic sludge blanket (UASB) reactors were started-up and operated for approximately 900 days to examine the feasibility of treating municipal wastewater under low temperature conditions. A modified solid distribution model was formulated by incorporating the variation of biogas production rate with a change in temperature. This model was used to optimize the sludge blanket height of UASB reactors for an effective operation of gas-liquid-solid (GLS) separation device. This model was found to simulate well the solid distribution as confirmed experimental observation of solid profile along the height of the reactor. Mathematical analysis of tracer curves indicated the presence of a mixed type of flow pattern in the sludge-bed zone of the reactor. It was found that the dead-zone and by-pass flow fraction were impacted by the change in operating temperatures. (author)

  11. Occurrence and profiles of bisphenol analogues in municipal sewage sludge in China

    International Nuclear Information System (INIS)

    Song, Shanjun; Song, Maoyong; Zeng, Luzhe; Wang, Thanh; Liu, Runzeng; Ruan, Ting; Jiang, Guibin

    2014-01-01

    Extensive use of bisphenol A and its analogues has caused increasing concern over the potential adverse health impacts of these chemicals. In this study, the presence and profiles of 13 bisphenols (BPs) were investigated in 52 municipal sewage sludge samples collected from 30 cities in China. Tetrabromobisphenol A was the most frequently observed analogue (geometric mean: 20.5 ng/g dw). Bisphenol A (4.69 ng/g dw), bisphenol S (3.02 ng/g dw), and bisphenol F (3.84 ng/g dw) were found with similar frequency. Other BP analogues such as tetrachlorobisphenol A, bisphenol AF, bisphenol E, and dihydroxybiphenyl were identified for the first time in sewage sludge in China. Significant correlations were found among BP concentrations, but no relationships were found with wastewater treatment plant characteristics. Profiles of the relative estradiol equivalents suggested that the estrogenic potential of BP mixtures may be associated with the occurrence and contributions of specific analogues. -- Highlights: • The profiles of various bisphenols were studied initially in sludge in China. • Analogous abundances were found for BPA, BPS and BPF. • Halo-substituted BPs have similar portions with BPA and its ascendant alternatives. • BPAF, TCBPA, BPE and DHBP were identified for the first time in sludge in China. -- We analyzed the profiles of bisphenol analogues in 52 sewage sludge samples with several bisphenols identified for the first time in wastewater treatment plants in China

  12. Migration and transformation of sulfur in the municipal sewage sludge during disposal in cement kiln.

    Science.gov (United States)

    Huang, Yuyan; Li, Haoxin; Jiang, Zhengwu; Yang, Xiaojie; Chen, Qing

    2018-05-07

    The aim of this work was to investigate the migration and transformation of sulfur in the municipal sewage sludge during disposal in cement kiln, and better understand the emission of the sulfur related pollutants in this process. In consideration of the temperature conditions in the practical operation, municipal sewage sludge was pre-dried at 105 °C, and then dried at 210, 260 and 310 °C, co-combusted with cement raw mill at 800, 900 and 1000 °C, and 1350, 1400 and 1450 °C respectively in the laboratory. X-ray photoelectron spectroscopy (XPS) was used to determine the S2p spectral lines of the municipal sewage sludge treated in the different process. Besides, The Thermal Analysis-Thermogravimetry (DTA-TG), Back Scattered Electron (BSE) and Energy Dispersive Spectrometer (EDS) were also employed to explore the mechanism of sulfur subsistence at 1450 °C. The results indicate that sulfide, thiophene, sulfone and sulfate are mainly sulfur compound in the municipal sewage sludge dried at 105 °C. Sulfoxide, a new sulfur compound, appears after it is further dried at 210 °C. The relative contents of sulfide and thiophene are continuously declined as the drying temperature increases due to their evaporation, decomposition and transformation in this process. The transformation of sulfide and thiophene makes the relative contents of sulfoxide and sulfate accordingly increased. However, the relative content of sulfone experiences an elevating-lowering process while the dry temperature elevated from 210 to 310 °C. This case is related to its evaporation and decomposition, as well as its production for the transformation of sulfide and thiophene. In the co-combustion process, sulfide, thiophene and sulfone are entirely vanished for their evaporation, decomposition and transformation. Sulfone is still contained at 800 °C, but when the temperature unceasingly rises, it is completely decomposed or evaporated and sulfate is the only sulfur compound. The

  13. Neural Networks Modelling of Municipal Real Estate Market Rent Rates

    Directory of Open Access Journals (Sweden)

    Muczyński Andrzej

    2016-12-01

    Full Text Available This paper presents the results of research on the application of neural networks modelling of municipal real estate market rent rates. The test procedure was based on selected networks trained on the local real estate market data and transformation of the detected dependencies – through established models – to estimate the potential market rent rates of municipal premises. On this basis, the assessment of the adequacy of the actual market rent rates of municipal properties was made. Empirical research was conducted on the local real estate market of the city of Olsztyn in Poland. In order to describe the phenomenon of market rent rates formation an unidirectional three-layer network and a network of radial base was selected. Analyses showed a relatively low degree of convergence of the actual municipal rent rents with potential market rent rates. This degree was strongly varied depending on the type of business ran on the property and its’ social and economic impact. The applied research methodology and the obtained results can be used in order to rationalize municipal property management, including the activation of rental policy.

  14. Marketing Communications in Public Administration : Case: Municipal IT Unit

    OpenAIRE

    Teräväinen, Terhi

    2011-01-01

    Marketing communications is traditionally associated with the private sector and commercial activities, but the term is nowadays also widely used in public sector contexts. In this thesis marketing communications is analysed from a public administration point of view. The empirical part deals with marketing communications executed by the Municipal IT Unit of the Ministry of Finance. The objective is to find out what is considered important when it comes to planning and implementing market...

  15. [Effect of microbial nutrient concentration on improvement of municipal sewage sludge dewaterability through bioleaching].

    Science.gov (United States)

    Song, Yong-wei; Liu, Fen-wu; Zhou, Li-xiang

    2012-08-01

    In this study, shaking flask batch experiments and practical engineering application tests were performed to investigate the effect of microbial nutrient concentration on the dewaterability of municipal sewage sludge with 2%, 3%, 4% and 5% solid contents via bioleaching. Meanwhile, the changes of pH value and the utilization efficiency of microbial nutrients during bioleaching were analyzed in this study. The results showed that the pH value decreased gradually at the beginning and then maintained a stable state in the treatments with different solid contents, and the nutrients were completely used up by the microorganisms after 2 days of bioleaching. It was found that the SRF of 2%, 3%, 4%, 5% sludges decreased quickly and then rose gradually with the extension of bioleaching time. In addition, the higher solid content the greater the increase. It was determined that the optimum microbial nutrient dosage for sludge with solid content of 2%, 3%, 4% and 5% were 3.0 g x L(-1), 4.5 g x L(-1), 8.3 g x L(-1) and 12.8 g x L(-1) respectively. At this point, the lowest SRF of sludge with each solid content were 0.61 x 10(12) m x kg(-1), 1.22 x 10(12) m x kg(-1), 3.09 x 10(12) m x kg(-1) and 4.83 x 10(12) m x kg(-1), respectively. Through the engineering application, it was showed that diluting the solid content of sewage sludge from 5% to 3% before bioleaching was feasible. It could not only improve the dewaterability of bioleached sewage sludge (the SRF declined from 3.29 x 10(12) m x kg(-1) to 1.10 x 10(12) m x kg(-1)), but also shorten the sludge nutrient time (shortened from 4 days to 2.35 days) and reduce the operation costs. Therefore, the results of this study have important significance for the engineering application of bioleaching of municipal sewage sludge with high solid content.

  16. Heavy metals in summer squash fruits grown in soil amended with municipal sewage sludge.

    Science.gov (United States)

    Antonious, George F; Snyder, John C; Dennis, Sam O

    2010-02-01

    The increasing awareness of the value of vegetables and fruits in the human diet requires monitoring of heavy metals in food crops. The effects of amending soil with compost made from municipal sewage sludge (MSS) and MSS mixed with yard waste (MSS-YW) on Cd, Cr, Mo, Cu, Zn, Pb, and Ni concentrations in soil and the potential bioaccumulation of heavy metals in squash fruits at harvest were investigated. A field study was conducted in a silty-loam soil at Kentucky State University Research Farm. Eighteen plots of 22 x 3.7 m each were separated using metal borders and the soil in six plots was mixed with MSS at 15 t acre(-1), six plots were mixed with MSS-YW at 15 t acre(-1) (on dry weight basis), and six unamended plots (no-mulch) were used for comparison purposes. Plots were planted with summer squash and heavy metals were analyzed in soil and mature fruits at harvest. Analysis of heavy metals in squash fruits was conducted using inductively coupled plasma spectrometry. Zinc and Cu concentrations in soil mixed with MSS were extremely high compared to other metals. In squash fruits, concentrations of Zn were generally greater than Cu. Total squash marketable yield was greatest in MSS-YW and MSS treatments compared to no-mulch conventional soil. Concentrations of Cd and Pb in soil amended with MSS averaged 0.1 and 1.4 mg kg(-1), respectively. These levels were much lower than the limits in the U.S. guidelines for using MSS in land farming. Data revealed that maximum concentrations of Cd and Pb in squash fruits were 0.03 and 0.01 microg g(-1) dry fruit, respectively. Nickel concentration in squash fruits fluctuated among harvest dates reaching a maximum of 2.5 microg g(-1) dry fruit. However, these concentrations were far below their permissible limits in edible fruits.

  17. Thermogravimetric analysis of the co-combustion of paper mill sludge and municipal solid waste

    International Nuclear Information System (INIS)

    Hu, Shanchao; Ma, Xiaoqian; Lin, Yousheng; Yu, Zhaosheng; Fang, Shiwen

    2015-01-01

    Highlights: • Thermogravimetric analysis of paper mill sludge and municipal solid waste were studied. • The combustion of paper mill sludge could be improved by blending municipal solid waste. • There existed significant interaction during co-combustion of the blends. • The OFW and Starink methods were used to obtain the activation energy. • The average activation energy was the lowest by blending 20% municipal solid waste. - Abstract: The thermal characteristics and kinetics of paper mill sludge (PMS), municipal solid waste (MSW) and their blends in the combustion process were investigated in this study. The mass percentages of PMS in the blends were 10%, 30%, 50%, 70% and 90%, respectively. The experiments were carried out at different heating rates (10 °C/min, 20 °C/min and 30 °C/min) and the temperature ranged from room temperature to 1000 °C in a thermogravimetric simultaneous thermal analyzer. The results suggested that the ignition temperature and burnout temperature of MSW were lower than that of PMS, and the mass loss rate of MSW was larger especially at low temperatures. There were only two mass loss peaks in the differential thermogravimetry (DTG) curve, while three mass loss peaks were observed when the blending ratios of PMS were 30%, 50%, 70%. The value of the comprehensive combustion characteristic index of the blends indicated a good combustibility when the percentage of PMS (PPMS) in the blends was less than 30%. There existed certain interaction between the combustion process of PMS and MSW, especially at high temperature stage. Activation energy (E) value obtained by the Ozawa–Flynn–Wall (OFW) method and the Starink method were very consistent. When the mass percentage of PMS in the blends was 80%, the E average value attained the minimum

  18. Bio-plastic (poly-hydroxy-alkanoate) production from municipal sewage sludge in the Netherlands: a technology push or a demand driven process?

    Science.gov (United States)

    Bluemink, E D; van Nieuwenhuijzen, A F; Wypkema, E; Uijterlinde, C A

    Valorisation of components from municipal 'waste' water and sewage sludge gets more and more attention in order to come to a circular economy by developing an efficient 'waste' to value concept. On behalf of the transition team 'Grondstoffenfabriek' ('Resource factory') a preliminary research was performed for all the Dutch water boards to assess the technical and economical feasibility of poly-hydroxy-alkanoate (PHA)-production from sewage sludge, a valuable product to produce bio-plastics. This study reveals that the production of bio-plastics from sewage sludge is feasible based on technical aspects, but not yet economically interesting, even though the selling price is relatively close to the actual PHA market price. (Selling price is in this particular case the indicative cost effective selling price. The cost effective selling price covers only the total production costs of the product.) Future process optimization (maximizing the volatile fatty acids production, PHA storage capacity, etc.) and market developments are needed and will result in cost reductions of the various sub-processes. PHA-production from sewage sludge at this stage is just a technology; every further research is needed to incorporate the backward integration approach, taking into account the market demand including associated product quality aspects.

  19. Disinfection of municipal sewage sludges in installation equipped with electron accelerator

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Zimek, Z.; Bryl-Sandelewska, T.; Kosmal, W.; Kalisz, L.; Kazmierczuk, M.

    1995-01-01

    Growing awareness of environment pollution hazards causes more and more stringent waste disposal regulations in many countries which stimulate searching for new methods of waste disposal, the best of which is recycling them after suitable treatment. Sludges from municipal sewage treatment plants contain organic and inorganic components valuable as soil fertilizer, so if disinfected they can be beneficially recycled in agriculture instead of being burdensome waste. Investigations performed in many countries showed that irradiation with a suitable dose of gamma or electron beam radiation makes sewage sludges sanitary safe and usable as soil fertilizer immediately after treatment. This paper describes some results of investigations performed in the Institute of Nuclear Chemistry and Technology and the Institute of Environmental Protection in Warsaw on the influence of 10 MeV electron beam on bacteria, parasites and parasite eggs present in sewage sludges from different municipal sewage treatment plants in Poland. Basic design parameters of the industrial installation elaborated on the basis of those experiments are presented. (Author)

  20. The Acimet{reg_sign} Process: An innovative approach to biogasification of municipal sludge

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S. [Univ. of Utah, Salt Lake City, UT (United States); Buoy, K. [DuPage County Dept. of Public Works, Wheaton, IL (United States)

    1993-12-31

    This paper reports the results of successful completion of an advanced anaerobic-digestion-process commercialization program supported by the County of DuPage, IL and the State of Illinois Department of Energy and Natural Resources, Springfield, IL. The project entailed anaerobic digestion of municipal sludge by pilot- and full-scale Acimet Process, which replaced an existing high-rate digestion system. The project was conducted at the Woodridge-Greenevalley wastewater treatment plant of DuPage County, IL. The Acimet Process relies on the application of two-phase anaerobic digestion for enhanced methane production and stabilization of municipal sludges, the disposal of which poses intractable problems in many municipal wastewater treatment plants. Unlike conventional anaerobic digestion processes, the Acimet System optimizes the liquefaction- acidification and acetogenic-methanogenic fermentations in separate acid- and methane-phase digesters operated at different hydraulic residence times (HRTs) to maximize feed hydrolysis and acidification, as well as biomethanation of the acidic intermediates. The Acimet System installed at the Woodridge Plant utilizes two mesophilic upflow digesters of novel design exhibiting unusually high product-formation efficiencies achieved without any mechanical mixing of the reactor contents.

  1. Optimization of municipal sludge and grease co-digestion using disintegration technologies.

    Science.gov (United States)

    Bouchy, L; Pérez, A; Camacho, P; Rubio, P; Silvestre, G; Fernández, B; Cano, R; Polanco, M; Díaz, N

    2012-01-01

    Many drivers tend to foster the development of renewable energy production in wastewater treatment plants as many expectations rely upon energy recovery from sewage sludge, for example through biogas use. This paper is focused on the assessment of grease waste (GW) as an adequate substrate for co-digestion with municipal sludge, as it has a methane potential of 479-710 LCH(4)/kg VS, as well as the evaluation of disintegration technologies as a method to optimize the co-digestion process. With this objective three different pre-treatments have been selected for evaluation: thermal hydrolysis, ultrasound and enzymatic treatment. Results have shown that co-digestion processes without pre-treatment had a maximum increment of 128% of the volumetric methane productivity when GW addition was 23% inlet (at 20 days of HRT and with an OLR of 3.0 kg COD/m(3)d), compared with conventional digestion of sewage sludge alone. Concerning the application of the selected disintegration technologies, all pre-treatments showed improvements in terms of methane yield (51.8, 89.5 and 57.6% more for thermal hydrolysis, ultrasound and enzymatic treatment, respectively, compared with non-pretreated wastes), thermal hydrolysis of GW and secondary sludge being the best configuration as it improved the solubilization of the organic matter and the hydrodynamic characteristics of digestates.

  2. Anaerobic co-digestion of swine and poultry manure with municipal sewage sludge.

    Science.gov (United States)

    Borowski, Sebastian; Domański, Jarosław; Weatherley, Laurence

    2014-02-01

    The anaerobic digestion of municipal sewage sludge (SS) with swine manure (SM) and poultry manure (PM) was undertaken. It was found that a mixture of sewage sludge with a 30% addition of swine manure gave around 400 dm(3)/kg VS of biogas, whereas the maximal biogas yield from ternary mixture (SS:SM:PM=70:20:10 by weight) was only 336 dm(3)/kg VS. An inhibition of methanogenesis by free ammonia was observed in poultry manure experiments. The anaerobic digestion was inefficient in pathogen inactivation as the reduction in the number of E. coli an Enterobacteriaceae was only by one logarithmic unit. A substantial portion of pathogens was also released into the supernatant. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. [Influences of municipal sludge applied in slope vegetation restoration on surface water environment].

    Science.gov (United States)

    Zhen, Chen Guang; Leng, Ping Sheng; Liu, Li Juan; Dou, De Quan; Hu, Zeng Hui

    2018-04-01

    The application of municipal sludge in ecological restoration has a good prospect for avoiding the food chain of grain crops, but its influences on surface water environmental are unclear. The municipal sludge and construction waste were mixed with 1:1 (V/V) as growth media, which were covered over simulation coal gangue slopes. Eight native woody species were sowed in the mixed media. The plant growth and coverage, as well as conductivity, pH, the concentrations of nitrogen (N), phosphorus (P), potassium (K), heavy metal and polycyclic aromatic hydrocarbon (PAHs) of surface and underground runoff of the slopes in the growing season were investigated. The results showed that plants grew well on the mixed media. The average plant coverage reached 60%. The pH of the surface and underground runoff changed little and near to neutral. The conductivity, N, P, K, heavy metal and PAHs contents of the slope runoff were high. The N and P contents in the growing season were above the National Standards of Surface Water Quality (GB 3838-2002) V. The contents of heavy metal were the highest in July. The contents of As lied at the GB IV-V, whereas other heavy metal contents up to GB II-IV. With strong rain leaching in the summer as well as the absorption, degrading and fix effect of plant-soil system on chemical substrates, the conductivity and N, P, K, heavy metal and PAHs contents of the slope runoff significantly decreased. The contents of heavy metal in late stage of growing season arrived at GB 2-3. The contents of PAHs reduced by about 50%. The direct application of municipal sludge in ecological restoration of coal gangue slope were beneficial to plant growth. The plant-soil system might gradually decrease the harmful substance concentrations in the growth media. The negative influences on surface water environment mainly came from eutrophication of N and P. Generally, the environmental safety is manageable.

  4. Extracellular polymeric substances (EPS) producing bacterial strains of municipal wastewater sludge: isolation, molecular identification, EPS characterization and performance for sludge settling and dewatering.

    Science.gov (United States)

    Bala Subramanian, S; Yan, S; Tyagi, R D; Surampalli, R Y

    2010-04-01

    Wastewater treatment plants often face the problems of sludge settling mainly due to sludge bulking. Generally, synthetic organic polymer and/or inorganic coagulants (ferric chloride, alum and quick lime) are used for sludge settling. These chemicals are very expensive and further pollute the environment. Whereas, the bioflocculants are environment friendly and may be used to flocculate the sludge. Extracellular polymeric substances (EPS) produced by sludge microorganisms play a definite role in sludge flocculation. In this study, 25 EPS producing strains were isolated from municipal wastewater treatment plant. Microorganisms were selected based on EPS production properties on solid agar medium. Three types of EPS (slime, capsular and bacterial broth mixture of both slime and capsular) were harvested and their characteristics were studied. EPS concentration (dry weight), viscosity and their charge (using a Zetaphoremeter) were also measured. Bioflocculability of obtained EPS was evaluated by measuring the kaolin clay flocculation activity. Six bacterial strains (BS2, BS8, BS9, BS11, BS15 and BS25) were selected based on the kaolin clay flocculation. The slime EPS was better for bioflocculation than capsular EPS and bacterial broth. Therefore, extracted slime EPS (partially purified) from six bacterial strains was studied in terms of sludge settling [sludge volume index (SVI)] and dewatering [capillary suction time (CST)]. Biopolymers produced by individual strains substantially improved dewaterability. The extracted slime EPS from six different strains were partially characterized. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  5. Valorization of pellets from municipal WWTP sludge in lightweight clay ceramics

    International Nuclear Information System (INIS)

    Cusido, Joan A.; Soriano, Cecilia

    2011-01-01

    A direct result of the growing number of municipal wastewater-treatment plants (WWTPs) has been an increase in the generation of large amounts of sewage sludge that requires environmentally acceptable final destination. To decrease the volume of sludge, a common technique is drying the sludge at a low temperature in rotary kilns. The result of this process is a granulated material consisting of dehydrated sludge pellets. After this treatment, this pelletized material becomes easier to manipulate, but it also becomes a more toxic waste, containing dangerous substances, mostly of the lipid type. At its final stage, this material is usually incinerated, used as a comburent material, used as an agricultural fertilizer, or used in the cement industry. Each application has its own problems and requires remediation measures from the safety and environmental viewpoints. In this study, we looked beyond these possible applications and analyzed the transformation of sewage sludge through a ceramization process into a material similar to expanded clays; we subsequently explored its uses in the building industry or in the agriculture industry, among others. Both the properties of the product material and the production method were characterized, and an environmental analysis was conducted. The new, lightweight material had a microstructure with open porosity and low thermal conductivity. Environmental characterization such as the leaching test revealed that undetectable amounts of hazardous metals from the sludge were present in the leachate after the sludge went through a thermal treatment, despite their initial presence (with the exception of vanadium, which could pose some restrictions on some of the proposed uses for the final product). Toxicity tests also showed negative results. The study of gaseous emissions during production revealed emissions factors similar to those during the production of conventional clay ceramics, although with higher organic emissions. As for

  6. Bio-Gas production from municipal sludge waste using anaerobic membrane bioreactor

    International Nuclear Information System (INIS)

    Lee, Y. H.; Lee, S.

    2009-01-01

    A laboratory scale anaerobic membrane bioreactor (AnMBR) system for the bio-methane gas production was operated for 60 days with municipal sludge wastes as a sole carbon source. The AnMRR system utilized the external cross-flow membrane module and was equipped with on-line data acquisition which enables continuous monitoring of the performance of both bioreactor and membrane through the analyses of pH, temperature, gas production; permeate flow rate, and transmembrane pressure (TMP). Such a configuration also provides an efficient tool to study rapid variations of monitoring membrane pressure (TMP). (Author)

  7. Mathematical experimental modeling for muffle furnace drying process of municipal sewage sludge in Beijing and Osaka

    International Nuclear Information System (INIS)

    Li, Xinyi; Takaoka, Masaki; Zhu, Fenfen; Oshita, Kazuyuki; Mizuno, Tadao; Morisawa, Shinsuke

    2010-01-01

    Over the past two decades, China has experienced rapid urbanization, which also leads to a lot of environmental problems including those of sewage sludge. As the amount of sewage sludge increases, conventional methods of treatment, such as compost and landfill, are facing the problems of limitations in demands or land. Considering that the demand of constructive materials in China keeps increasing, reusing municipal sewage sludge (MSS) in cement manufactory plant as fuels and raw materials is another practicable way to deal with it. The aim of this study is to describe the process of the heating of sewage sludge under different atmospheres of nitrogen and oxygen, and to find out some relation between the moisture of MSS and the heating time under different surrounding temperature by means of a mathematical model. In this study, we compared 4 kinds of MSS sampled in Beijing and Osaka. First of all, we defined the differences in those fundamental physical properties, such as concentration of various elements, calorific values and so on. Then the macroscopical thermal properties of the sludges were observed by means of thermogravimetric (TG) analysis. Both pyrolysis and combustion of 4 samples of MSS were studied by TG dynamic runs carried out at 10K/m. Visual observation of the heating profiles shows three stages in the heating process, which have been characterized. At last, we focused on batch processing drying tests using muffle furnace under temperature of 200, 250 and 300 degrees Celsius. The volatile matters loss besides moisture during heating process was evaluated and the experimental drying curves were matched with a mathematical model. (author)

  8. Simulation of co-incineration of sewage sludge with municipal solid waste in a grate furnace incinerator.

    Science.gov (United States)

    Lin, Hai; Ma, Xiaoqian

    2012-03-01

    Incineration is one of the most important methods in the resource recovery disposal of sewage sludge. The combustion characteristics of sewage sludge and an increasing number of municipal solid waste (MSW) incineration plants provide the possibility of co-incineration of sludge with MSW. Computational fluid dynamics (CFD) analysis was used to verify the feasibility of co-incineration of sludge with MSW, and predict the effect of co-incineration. In this study, wet sludge and semi-dried sludge were separately blended with MSW as mixed fuels, which were at a co-incineration ratios of 5 wt.% (wet basis, the same below), 10 wt.%, 15 wt.%, 20 wt.% and 25 wt.%. The result indicates that co-incineration of 10 wt.% wet sludge with MSW can ensure the furnace temperature, the residence time and other vital items in allowable level, while 20 wt.% of semi-dried sludge can reach the same standards. With lower moisture content and higher low heating value (LHV), semi-dried sludge can be more appropriate in co-incineration with MSW in a grate furnace incinerator. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Microalgae Cultivation on Anaerobic Digestate of Municipal Wastewater, Sewage Sludge and Agro-Waste

    Directory of Open Access Journals (Sweden)

    Luca Zuliani

    2016-10-01

    Full Text Available Microalgae are fast-growing photosynthetic organisms which have the potential to be exploited as an alternative source of liquid fuels to meet growing global energy demand. The cultivation of microalgae, however, still needs to be improved in order to reduce the cost of the biomass produced. Among the major costs encountered for algal cultivation are the costs for nutrients such as CO2, nitrogen and phosphorous. In this work, therefore, different microalgal strains were cultivated using as nutrient sources three different anaerobic digestates deriving from municipal wastewater, sewage sludge or agro-waste treatment plants. In particular, anaerobic digestates deriving from agro-waste or sewage sludge treatment induced a more than 300% increase in lipid production per volume in Chlorella vulgaris cultures grown in a closed photobioreactor, and a strong increase in carotenoid accumulation in different microalgae species. Conversely, a digestate originating from a pilot scale anaerobic upflow sludge blanket (UASB was used to increase biomass production when added to an artificial nutrient-supplemented medium. The results herein demonstrate the possibility of improving biomass accumulation or lipid production using different anaerobic digestates.

  10. AN EXPERIMENTAL STUDY ON THE RHEOLOGICAL PROPERTIES OF CONDITIONED MUNICIPAL ACTIVATED SLUDGE

    Directory of Open Access Journals (Sweden)

    SALAM K. AL-DAWERY

    2017-01-01

    Full Text Available This research work was focused on the rheological characteristics of conditioned fresh activated sludge using TA rheometer HR-2. The effect of cationic polyelectrolyte conditioner has been investigated for floc size, surface properties and yield stress at different pH values in a comparative fashion. Our approach was to reveal the effect of polymer on the municipal activated sludge with high organic contents up to 80%. The results indicated an improvement of 50% in settling properties by addition polyelectrolyte up to 4 mg/g solid/l. Rheological data analysis showed that responses of shear stress - shear rate were found to be closest to Bingham model and gave almost similar and smaller k values of average 6.2×10-3. The results of shear creep indicated that all sludge samples have less rigid structures with no reconstruction behavior. The optical analyses of the samples indicated that the floc sizes were increased with successive addition of polyelectrolyte. The increase of floc sizes caused large stresses especially for solution with pH=9. As the flocculation accorded despite the negative zeta potential, this phenomenon can be referred to that interparticles hydrogen bridging was governing flocculation rather than charge neutralization. Also, during the experiment, bacterial growth showed an adaption despite the conditioning with polyelectrolyte.

  11. Potential role of intense ionising radiation sources in municipal sludge management and environmental protection

    International Nuclear Information System (INIS)

    Krishnamurthy, K.

    1980-01-01

    Magnitude of the problem of safe disposal of sewage and sludge is explained. With rapid increase in the quantum of generated municipal and industrial wastes, their disposal on land or in sea is becoming harmful to public health, hazardous to aquatic life and disturbing to ecological balance. These wastes can be recycled, but to make this recycling beneficial and at the same time harmless to public health, the wastes must be disinfected. Radiation disinfection of sewage and sludge is examined as one of the ways of disinfection. Irradiation can be carried out with gamma radiation or energised electrons. Techniques of radiation disinfection and radiation doses required for disinfection are discussed. Case studies of a few radiation plants for sludge disinfection are presented. They include the Palmdale Plant in Florida, Sandia Irradiator at Albuqurque, New Mexico, Energised Electron Facility at Deer Island, Boston - all these in U.S.A., and the Munich Plant in West Germany. Mention has been made to the work in progress in India on the design of irradiators. Reference has been made to the proposed electron irradiation system for destruction of toxic chemicals such as PCB in drinking water and for disinfection of secondary water. Economics of radiation disinfection is also discussed and it is noted that the radiation process can become economically competitive when cheap sources of radiation become available. (M.G.B.)

  12. Anaerobic Codigestion of Municipal Wastewater Treatment Plant Sludge with Food Waste: A Case Study

    Directory of Open Access Journals (Sweden)

    Zubayeda Zahan

    2016-01-01

    Full Text Available The aim of this study was to assess the effects of the codigestion of food manufacturing and processing wastes (FW with sewage sludge (SS, that is, municipal wastewater treatment plant primary sludge and waste activated sludge. Bench scale mesophilic anaerobic reactors were fed intermittently with varying ratio of SS and FW and operated at a hydraulic retention time of 20 days and organic loading of 2.0 kg TS/m3·d. The specific biogas production (SBP increased by 25% to 50% with the addition of 1%–5% FW to SS which is significantly higher than the SBP from SS of 284±9.7 mLN/g VS added. Although the TS, VS, and tCOD removal slightly increased, the biogas yield and methane content improved significantly and no inhibitory effects were observed as indicated by the stable pH throughout the experiment. Metal screening of the digestate suggested the biosolids meet the guidelines for use as a soil conditioner. Batch biochemical methane potential tests at different ratios of SS : FW were used to determine the optimum ratio using surface model analysis. The results showed that up to 47-48% FW can be codigested with SS. Overall these results confirm that codigestion has great potential in improving the methane yield of SS.

  13. The Romanian Municipal Bond Market and the International Financial Crisis

    Directory of Open Access Journals (Sweden)

    VALENTINA VASILE

    2010-06-01

    Full Text Available In Romania, the bond market was set up later, comparatively to the equity market. This market is in a development process, but the international financial crisis has affected even the interest of investors in bonds. The secondary municipal bond market is not a very liquid market because these securities are bought from the primary market and held in portfolios by investors because these bonds have a low risk. The issue of these bonds is correlated with the financial independence and the level of decentralization of the local public authorities. The issuance of these bonds is correlated with financial independence and decentralization level specific to local public authorities. Under crisis conditions, the volatility of this market is more significant, the increasing deficits of local budgets decreasing the interest of the middle-class in investing in such financial instruments.

  14. Coagulant recovery from water treatment plant sludge and reuse in post-treatment of UASB reactor effluent treating municipal wastewater.

    Science.gov (United States)

    Nair, Abhilash T; Ahammed, M Mansoor

    2014-09-01

    In the present study, feasibility of recovering the coagulant from water treatment plant sludge with sulphuric acid and reusing it in post-treatment of upflow anaerobic sludge blanket (UASB) reactor effluent treating municipal wastewater were studied. The optimum conditions for coagulant recovery from water treatment plant sludge were investigated using response surface methodology (RSM). Sludge obtained from plants that use polyaluminium chloride (PACl) and alum coagulant was utilised for the study. Effect of three variables, pH, solid content and mixing time was studied using a Box-Behnken statistical experimental design. RSM model was developed based on the experimental aluminium recovery, and the response plots were developed. Results of the study showed significant effects of all the three variables and their interactions in the recovery process. The optimum aluminium recovery of 73.26 and 62.73 % from PACl sludge and alum sludge, respectively, was obtained at pH of 2.0, solid content of 0.5 % and mixing time of 30 min. The recovered coagulant solution had elevated concentrations of certain metals and chemical oxygen demand (COD) which raised concern about its reuse potential in water treatment. Hence, the coagulant recovered from PACl sludge was reused as coagulant for post-treatment of UASB reactor effluent treating municipal wastewater. The recovered coagulant gave 71 % COD, 80 % turbidity, 89 % phosphate, 77 % suspended solids and 99.5 % total coliform removal at 25 mg Al/L. Fresh PACl also gave similar performance but at higher dose of 40 mg Al/L. The results suggest that coagulant can be recovered from water treatment plant sludge and can be used to treat UASB reactor effluent treating municipal wastewater which can reduce the consumption of fresh coagulant in wastewater treatment.

  15. Production of biosolid fuels from municipal sewage sludge: Technical and economic optimisation.

    Science.gov (United States)

    Wzorek, Małgorzata; Tańczuk, Mariusz

    2015-08-01

    The article presents the technical and economic analysis of the production of fuels from municipal sewage sludge. The analysis involved the production of two types of fuel compositions: sewage sludge with sawdust (PBT fuel) and sewage sludge with meat and bone meal (PBM fuel). The technology of the production line of these sewage fuels was proposed and analysed. The main objective of the study is to find the optimal production capacity. The optimisation analysis was performed for the adopted technical and economic parameters under Polish conditions. The objective function was set as a maximum of the net present value index and the optimisation procedure was carried out for the fuel production line input capacity from 0.5 to 3 t h(-1), using the search step 0.5 t h(-1). On the basis of technical and economic assumptions, economic efficiency indexes of the investment were determined for the case of optimal line productivity. The results of the optimisation analysis show that under appropriate conditions, such as prices of components and prices of produced fuels, the production of fuels from sewage sludge can be profitable. In the case of PBT fuel, calculated economic indexes show the best profitability for the capacity of a plant over 1.5 t h(-1) output, while production of PBM fuel is beneficial for a plant with the maximum of searched capacities: 3.0 t h(-1). Sensitivity analyses carried out during the investigation show that influence of both technical and economic assessments on the location of maximum of objective function (net present value) is significant. © The Author(s) 2015.

  16. Hydrothermal Liquefaction and Upgrading of Municipal Wastewater Treatment Plant Sludge: A Preliminary Techno-Economic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhu, Yunhua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susanne B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schmidt, Andrew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hallen, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billing, Justin M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Todd R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Samuel P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Maupin, Gary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-06-08

    A preliminary process model and techno-economic analysis (TEA) was completed for fuel produced from hydrothermal liquefaction (HTL) of sludge waste from a municipal wastewater treatment plant (WWTP) and subsequent biocrude upgrading. The model is adapted from previous work by Jones et al. (2014) for algae HTL, using experimental data generated in fiscal year 2015 (FY15) bench-scale HTL testing of sludge waste streams. Testing was performed on sludge samples received from MetroVancouver’s Annacis Island WWTP (Vancouver, B.C.) as part of a collaborative project with the Water Environment and Reuse Foundation (WERF). The full set of sludge HTL testing data from this effort will be documented in a separate report to be issued by WERF. This analysis is based on limited testing data and therefore should be considered preliminary. Future refinements are necessary to improve the robustness of the model, including a cross-check of modeled biocrude components with the experimental GCMS data and investigation of equipment costs most appropriate at the smaller scales used here. Environmental sustainability metrics analysis is also needed to understand the broader impact of this technology pathway. The base case scenario for the analysis consists of 10 HTL plants, each processing 100 dry U.S. ton/day (92.4 ton/day on a dry, ash-free basis) of sludge waste and producing 234 barrel per stream day (BPSD) biocrude, feeding into a centralized biocrude upgrading facility that produces 2,020 barrel per standard day of final fuel. This scale was chosen based upon initial wastewater treatment plant data collected by the resource assessment team from the EPA’s Clean Watersheds Needs Survey database (EPA 2015a) and a rough estimate of what the potential sludge availability might be within a 100-mile radius. In addition, we received valuable feedback from the wastewater treatment industry as part of the WERF collaboration that helped form the basis for the selected HTL and upgrading

  17. Simultaneous heavy metals removal and municipal sewage sludge dewaterability improvement in bioleaching processes by various inoculums.

    Science.gov (United States)

    Shi, Chaohong; Zhu, Nengwu; Shang, Ru; Kang, Naixin; Wu, Pingxiao

    2015-11-01

    The heavy metals content and dewaterability of municipal sewage sludge (MSS) are important parameters affecting its subsequent disposal and land application. Six kinds of inoculums were prepared to examine the characteristics of heavy metals removal and MSS dewaterability improvement in bioleaching processes. The results showed that Cu, Zn and Cd bioleaching efficiencies (12 days) were 81-91, 87-93 and 81-89%, respectively, which were significantly higher than those of Fe-S control (P bioleaching boosted by the prepared inoculums could also significantly enhance MSS dewaterability (P bioleaching for heavy metals removal and dewaterability improvement. It also suggested that the synergy of sulfur/ferrous-oxidizing bacteria (SFOB) enriched from AMD and the cooperation of exogenous and indigenous SFOB significantly promoted bioleaching efficiencies.

  18. A kinetic model of municipal sludge degradation during non-catalytic wet oxidation.

    Science.gov (United States)

    Prince-Pike, Arrian; Wilson, David I; Baroutian, Saeid; Andrews, John; Gapes, Daniel J

    2015-12-15

    Wet oxidation is a successful process for the treatment of municipal sludge. In addition, the resulting effluent from wet oxidation is a useful carbon source for subsequent biological nutrient removal processes in wastewater treatment. Owing to limitations with current kinetic models, this study produced a kinetic model which predicts the concentrations of key intermediate components during wet oxidation. The model was regressed from lab-scale experiments and then subsequently validated using data from a wet oxidation pilot plant. The model was shown to be accurate in predicting the concentrations of each component, and produced good results when applied to a plant 500 times larger in size. A statistical study was undertaken to investigate the validity of the regressed model parameters. Finally the usefulness of the model was demonstrated by suggesting optimum operating conditions such that volatile fatty acids were maximised. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Treatment of municipal landfill leachate using a combined anaerobic digester and activated sludge system

    International Nuclear Information System (INIS)

    Kheradmand, S.; Karimi-Jashni, A.; Sartaj, M.

    2010-01-01

    The main objective of this study was to assess the feasibility of treating sanitary landfill leachate using a combined anaerobic and activated sludge system. A high-strength leachate from Shiraz municipal landfill site was treated using this system. A two-stage laboratory-scale anaerobic digester under mesophilic conditions and an activated sludge unit were used. Landfill leachate composition and characteristics varied considerably during 8 months experiment (COD concentrations of 48,552-62,150 mg/L). It was found that the system could reduce the COD of the leachate by 94% at a loading rate of 2.25 g COD/L/d and 93% at loading rate of 3.37 g COD/L/d. The anaerobic digester treatment was quite effective in removing Fe, Cu, Mn, and Ni. However, in the case of Zn, removal efficiency was about 50%. For the rest of the HMs the removal efficiencies were in the range 88.8-99.9%. Ammonia reduction did not occur in anaerobic digesters. Anaerobic reactors increased alkalinity about 3.2-4.8% in the 1st digester and 1.8-7.9% in the 2nd digester. In activated sludge unit, alkalinity and ammonia removal efficiency were 49-60% and 48.6-64.7%, respectively. Methane production rate was in the range of 0.02-0.04, 0.04-0.07, and 0.02-0.04 L/g COD rem for the 1st digester, the 2nd digester, and combination of both digesters, respectively; the methane content of the biogas varied between 60% and 63%.

  20. Partial oxidation of municipal sludge with activited carbon catalyst in supercritical water

    International Nuclear Information System (INIS)

    Guo Yang; Wang Shuzhong; Gong Yanmeng; Xu Donghai; Tang Xingying; Ma Honghe

    2010-01-01

    The partial oxidation (POX) characteristics of municipal sludge in supercritical water (SCW) were investigated by using batch reactor. Effects of reaction parameters such as oxidant equivalent ratio (OER), reaction time and temperature were investigated. Activated carbon (AC) could effectively improve the mole fraction of H 2 in gas product at low OER. However, high OER (greater than 0.3) not only led to the combustion reaction of CO and H 2 , but also caused corrosion of reactor inner wall. Hydrogenation and polymerization of the intermediate products are possible reasons for the relative low COD removal rate in our tests. Metal oxide leached from the reactor inner wall and the main components of the granular sludge were deposited in the AC catalyst. Reaction time had more significant effect on BET surface area of AC than OER had. Long reaction time led to the methanation reaction following hydrolysis and oxidation reaction of AC in SCW in the presence of oxygen. Correspondingly, the possible reaction mechanisms were proposed.

  1. Persistence of perfluoroalkylated substances in closed bottle tests with municipal sewage sludge.

    Science.gov (United States)

    Sáez, Monica; de Voogt, Pim; Parsons, John R

    2008-09-01

    Perfluoroalkylated substances (PFAS) are chemicals with completely fluorinated alkyl chains. The specific properties of the F-C bond give PFAS a high stability and make them very useful in a wide range of applications. PFAS also pose a potential risk to the environment and humans because they have been recently characterized as persistent, bioaccumulative, and toxic. The objective of this work is to study the bacterial degradation of PFAS under aerobic and anaerobic conditions in municipal sewage sludge as a contribution toward understanding their environmental fate and behavior. Bacterial communities from sewage sludge were exposed to a mixture of PFAS under aerobic or anaerobic conditions. Individual PFAS concentrations were determined in the experiment media at different exposure times using liquid chromatography-mass spectrometry analysis after extraction with solid-phase extraction. The PFAS analyses of samples of sludge showed repeatable replicate results, allowing a reliable quantification of the different groups of PFAS analyzed. No conclusive evidence for PFAS degradation was observed under the experimental conditions tested in this work. Reduction in concentrations, however, was observed for some PFAS in sludge under aerobic conditions. The largest concentration decrease occurred for the fluorotelomer alcohols (FTOHs), especially for the 8:2 FTOH, which have been described as biodegradable in the literature. However, this concentration decrease could be due to different causes: sorption to glass, septa, or matrix components, as well as bacterial activity. Therefore, it is not certain that biodegradation occurred. PFAS are very recalcitrant chemicals, especially when fully fluorinated. Although some decreases in concentration have been observed for some PFAS, such as the FTOHs, there is no conclusive evidence for biodegradation. It can be concluded that the PFAS tested in these experiments are non-biodegradable under these experimental conditions. Since

  2. Leachability of Heavy Metals from Lightweight Aggregates Made with Sewage Sludge and Municipal Solid Waste Incineration Fly Ash

    Science.gov (United States)

    Wei, Na

    2015-01-01

    Lightweight aggregate (LWA) production with sewage sludge and municipal solid waste incineration (MSWI) fly ash is an effective approach for waste disposal. This study investigated the stability of heavy metals in LWA made from sewage sludge and MSWI fly ash. Leaching tests were conducted to find out the effects of MSWI fly ash/sewage sludge (MSWI FA/SS) ratio, sintering temperature and sintering time. It was found that with the increase of MSWI FA/SS ratio, leaching rates of all heavy metals firstly decreased and then increased, indicating the optimal ratio of MSWI fly ash/sewage sludge was 2:8. With the increase of sintering temperature and sintering time, the heavy metal solidifying efficiencies were strongly enhanced by crystallization and chemical incorporations within the aluminosilicate or silicate frameworks during the sintering process. However, taking cost-savings and lower energy consumption into account, 1100 °C and 8 min were selected as the optimal parameters for LWA sample- containing sludge production. Furthermore, heavy metal leaching concentrations under these optimal LWA production parameters were found to be in the range of China’s regulatory requirements. It is concluded that heavy metals can be properly stabilized in LWA samples containing sludge and cannot be easily released into the environment again to cause secondary pollution. PMID:25961800

  3. Modeling the pH-mediated Extraction of Ionizable Organic Contaminants to Improve the Quality of Municipal Sewage Sludge Destined for Land Application

    OpenAIRE

    Venkatesan, Arjun K.; Halden, Rolf U.

    2016-01-01

    A model was developed to assess the impact of adding acids and bases to processed municipal sewage sludge (MSS) to mobilize contaminants, facilitating their removal from sludge by flushing prior to land application. Among 312 organic contaminants documented to occur in U.S. MSS, 71 or 23% were identified as ionizable organic contaminants (IOCs), contributing a disproportionately large fraction of 82% of the total mass of sludge-borne contaminants. Detected IOCs included 57 pharmaceuticals and...

  4. Municipal energy and climate policy in a liberalized energy market

    International Nuclear Information System (INIS)

    Burger, H.

    2001-05-01

    Due to the ongoing process of liberalisation, Dutch municipal energy policy is undergoing significant changes. The probable privatisation of energy companies, the change from what used to be 'their' local energy company to what will become an energy company, results in a need for local administrations to build up energy knowledge, end-use information and financial resources that 'their' energy companies used to share but, because of operating in a competitive market, are now more reluctant to do so. On the other hand offers privatisation and the selling of shares the possibility for some local governments to collect a significant sum of money which can be addressed to energy policy. This process of growing responsibility of local administrations for their own energy policy coincides with the structural change of the nature of the energy supply in the Netherlands. The change towards a more decentralised energy supply results in more energy systems (e.g. PV and wind) coming under the influence of local regulations. Municipal governments will have to act more like actors in a complex policy network, playing different roles at different times in different situations, often stimulating and regulating at the same time. The growing popularity of platforms like energy agencies, bringing together parties like the local government, energy companies and commercial- and housing associations are examples hereof. In this report, another new role for local governments resulting from the liberalisation process is highlighted: the role of energy consumer. It is estimated that the aggregated electricity demand resulting from activities under direct municipal responsibility (e.g. municipal dwellings, traffic lights, public lighting) amounts to a fairly large share of the market. Due to the public interests vested in the local administrations, it is expected that an important part of this demand is demand for green electricity. Also, local governments can use the energy markets to act

  5. Electrodialytic treatment of municipal wastewater and sludge for the removal of heavy metals and recovery of phosphorus

    DEFF Research Database (Denmark)

    Ebbers, Benjamin; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2015-01-01

    Municipal wastewater and sewage sludge is an abundant source of phosphorus (P), but its usage is often limited due to wastewater treatment methods and contaminants, mostly heavy metals (HM's). Three compartment (3C) electrodialysis (ED) was used to simultaneously extract HM's (Cd, Cr, Cu, Ni, Pb...... of heavy metals or recovery of phosphorus using ED, the end-products in wastewater treatment, like anaerobically digested sludge and reject-water streams, are therefore best to be treated....... pH using anaerobically digested sludge. The hydrolysis of OM during anaerobic digestion and the anaerobic conditions allowed for easier extraction of HM's such as Cd, Ni and Zn as they had fewer adsorption places, and improved P availability and extractability. Extraction of P from high...

  6. Market forces in municipal and industrial waste-to-energy

    International Nuclear Information System (INIS)

    Makansi, J.

    1991-01-01

    The market for municipal and industrial waste-to-energy can be characterized simply as currently soft with continued excellent long-term prospects. But as in all markets large and small, niche opportunities exist now which can be profitable with proper definition and strategy. Economics of several projects have proven marginal, cost overruns are common, and revenue projections are sometimes overstates. Also contributing to poorer economics of late are lower prices for the electric power produced from these plants. New environmental restrictions are adding 10-15% to the capital costs of a given project. On the industrial front, the strength of waste-fuel firing continues to be evident for independent power production. Important fuel-niche markets have sprung up over the last decade including petroleum coke, coal-mining wastes, hospital or redbag wastes, biomass, used tires, and so on. Another fuel niche is hazardous waste incineration. In the municipal arena, realism has not yet hit the recycling and source reduction enthusiasts. Only 25-35% recycling is considered practical by experts. There are also limits to how often material can be recycled. Finally, in spite of the best efforts of the population to control the amount of refuse generated and to recycle that which is, population and economic growth may overtake any new sense of environmental responsibility. And, yes, the additional refuse still has to go somewhere exclamation point The best somewhere option continues to be a waste-to-energy plant. Current market opportunities and two other market forces (international activities and the role of US utilities) are discussed

  7. Studies on the co-treatment of the municipal sewage sludge and oil wastes by using microorganism from the land farming of the PETROBRAS President Getulio Vargas refinery - REPAR; Estudos sobre o co-tratamento de lodo de esgoto domestico e residuos oleosos com microorganismos do landfarming da refinaria Presidente Getulio Vargas, PETROBRAS/REPAR

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Rodrigo Azevedo; Goncalves, Claudia Martins; Krenczynski, Michele Cristine; Nascimento Neto, Durval [Universidade Federal do Parana (UFPR), Curitiba (Brazil). Curso de Pos-Graduacao em Ciencia do Solo; Carvalho, Francisco Jose Pereira de Campos [Universidade Federal do Parana (UFPR), Curitiba (Brazil). Dept. de Solos; Grube, Karl; Coelho, Ibirajara Jorge Evangelhista [PETROBRAS, PR (Brazil). REPAR

    1998-07-01

    In the present work a set of results from the evaluation of the use of oily substrate for biodegration of municipal sewage sludge, with microorganisms from the landfaming are presented. The treatments of contaminated soil with sewage sludge, were: inoculum plus oily substrate, landfarming plus inoculum and only municipal sludge. In all treatments the municipal sewage sludge was varied. The obtained results indicate possible treatment of municipal sewage sludge with landfarming microorganisms plus oily substrates. (author)

  8. Evaluation of the influence of mechanical activation on physical and chemical properties of municipal solid waste incineration sludge.

    Science.gov (United States)

    Caprai, V; Florea, M V A; Brouwers, H J H

    2018-06-15

    Despite numerous studies concerning the application of by-products in the construction field, municipal solid waste incineration (MSWI) residues are not widely used as secondary building materials. In some European countries, washing treatment to the full bottom ash (BA) fraction (0-32 mm) is applied, isolating more contaminated particles, smaller than 0.063 mm. Therefore, a MWSI sludge is produced, having a high moisture content, and thus a limited presence of soluble species. In order to enhance its performance as building material, here, dry mechanical activation is applied on MSWI sludge. Thereafter, a reactivity comparison between reference BA and untreated and treated MSWI sludge is provided, evaluating their behaviour in the presence of cement and their pozzolanic activity. Moreover, the mechanical performances, as 25% substitution of Portland cement (PC) are assessed, based on the EN 450. Mechanical activation enhances MSWI sludge physically due to the improved particle morphology and packing. Chemically, the hydration degree of PC is enhanced by the MSWI sludge by ≈25%. The milling treatment proved to be beneficial to the residues performances in the presence of PC, providing 32% higher strength than untreated sample. Environmentally, the compliance with the unshaped material legislation is successfully verified, according to the Soil Quality Decree. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Alternative treatment for septic tank sludge: co-digestion with municipal solid waste in bioreactor landfill simulators.

    Science.gov (United States)

    Valencia, R; den Hamer, D; Komboi, J; Lubberding, H J; Gijzen, H J

    2009-02-01

    Co-disposal of septic tank sludge had a positive effect on the municipal solid waste (MSW) stabilisation process in Bioreactor Landfill simulators. Co-disposal experiments were carried out using the Bioreactor Landfill approach aiming to solve the environmental problems caused by indiscriminate and inadequate disposal of MSW and especially of septic tank sludge. The simulator receiving septic tank sludge exhibited a 200 days shorter lag-phase as compared to the 350 days required by the control simulator to start the exponential biogas production. Additionally, the simulator with septic sludge apparently retained more moisture (>60% w/w), which enhanced the overall conversion of organic matter hence increasing the biogas production (0.60 m3 biogas kg(-1)VS(converted)) and removal efficiency of 60% for VS from the simulator. Alkaline pH values (pH>8.5) did not inhibit the biogas production; moreover it contributed to reduce partially the negative effects of NH(4)(+) (>2 g L(-1)) due to NH(3) volatilisation thus reducing the nitrogen content of the residues. Associated risks and hazards with septage disposal were practically eliminated as total coliform and faecal coliform contents were reduced by 99% and 100%, respectively at the end of the experiment. These results indicate that co-disposal has two direct benefits, including the safe and environmentally sound disposal of septic tank sludge and an improvement of the overall performance of the Bioreactor Landfill by increasing moisture retention and supplying a more acclimatised bacterial population.

  10. Comparison of ozone and thermal hydrolysis combined with anaerobic digestion for municipal and pharmaceutical waste sludge with tetracycline resistance genes.

    Science.gov (United States)

    Pei, Jin; Yao, Hong; Wang, Hui; Ren, Jia; Yu, Xiaohua

    2016-08-01

    Biosolids from wastewater treatment plant (WWTP) are environmental reservoirs of antibiotic resistance genes, which attract great concerns on their efficient treatments. Anaerobic digestion (AD) is widely used for sewage sludge treatment but its effectiveness is limited due to the slow hydrolysis. Ozone and thermal hydrolysis pre-treatment were employed to improve AD efficiency and reduce antibiotic-resistant genes in municipal and pharmaceutical waste sludge (MWS and PWS, respectively) in this study. Sludge solubilization achieved 15.75-25.09% and 14.85-33.92% after ozone and thermal hydrolysis, respectively. Both pre-treatments improved cumulative methane production and the enhancements were greater on PWS than MWS. Five tetracycline-resistant genes (tet(A), tet(G), tet(Q), tet(W), tet(X)) and one mobile element (intI1) were qPCR to assess pre-treatments. AD of pre-treated sludge reduced more tet genes than raw sludge for both ozonation and thermal hydrolysis in PWS and MWS. Thermal hydrolysis pre-treatment was more efficient than ozone for reduction after AD. Results of this study help support management options for reducing the spread of antibiotic resistance from biosolids. Copyright © 2016. Published by Elsevier Ltd.

  11. The long-term and the short-term at a cropping municipal sewage sludge disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Welby, C.W. (North Carolina State Univ., Raleigh, NC (United States). Dept. of Marine, Earth and Atmospheric Sciences)

    1994-03-01

    The City of Raleigh, NC, chose land application of municipal sewage sludge as a means of reducing pollution to the Neuse River. The Neuse River Waste Water Treatment Plant (NRWWTP) is located in the Piedmont Province of North Carolina. The soils at the facility are derived largely from the Rolesville Granite. Sewage sludge is applied to over 640 acres of cropland, owned in fee or leased. In making the policy decision for use of the sludge land application method 20 or so years ago, the City had to evaluate the potential for heavy metal accumulation in the soils and plants as well as the potential for ground-water contamination from the nitrate-nitrogen. The city also had to make a policy decision about limiting the discharge of heavy metals to the sewer system. Study of data from monitoring wells demonstrate that well position is a key in determining whether or not nitrate-nitrogen contamination is detected. Data from a three-year study suggest that nitrate-nitrogen moves fairly rapidly t the water table, although significant buildup in nitrogen-nitrogen may take a number of years. Evidence exists suggesting that the time between application of sewage sludge and an increase of nitrate-nitrogen at the water table may be on the order of nine months to a year. It is apparent that in the case of municipal sewage sludge application one can anticipate some nitrate-nitrogen buildup and that the public policy on drinking water standards must recognize this fact.

  12. The long-term and the short-term at a cropping municipal sewage sludge disposal facility

    International Nuclear Information System (INIS)

    Welby, C.W.

    1994-01-01

    The City of Raleigh, NC, chose land application of municipal sewage sludge as a means of reducing pollution to the Neuse River. The Neuse River Waste Water Treatment Plant (NRWWTP) is located in the Piedmont Province of North Carolina. The soils at the facility are derived largely from the Rolesville Granite. Sewage sludge is applied to over 640 acres of cropland, owned in fee or leased. In making the policy decision for use of the sludge land application method 20 or so years ago, the City had to evaluate the potential for heavy metal accumulation in the soils and plants as well as the potential for ground-water contamination from the nitrate-nitrogen. The city also had to make a policy decision about limiting the discharge of heavy metals to the sewer system. Study of data from monitoring wells demonstrate that well position is a key in determining whether or not nitrate-nitrogen contamination is detected. Data from a three-year study suggest that nitrate-nitrogen moves fairly rapidly t the water table, although significant buildup in nitrogen-nitrogen may take a number of years. Evidence exists suggesting that the time between application of sewage sludge and an increase of nitrate-nitrogen at the water table may be on the order of nine months to a year. It is apparent that in the case of municipal sewage sludge application one can anticipate some nitrate-nitrogen buildup and that the public policy on drinking water standards must recognize this fact

  13. Phytoremediation potential of water caltrop (Trapa natans L.) using municipal wastewater of the activated sludge process-based municipal wastewater treatment plant.

    Science.gov (United States)

    Kumar, Vinod; Chopra, A K

    2018-01-01

    Phytoremediation experiments were carried out to assess the phytoremediation potential of water caltrop (Trapa natans L.) using municipal wastewater collected from the activated sludge process- (ASP) based municipal wastewater treatment plant. The results revealed that T. natans significantly (P ≤ .05/P ≤ .01/P ≤ .001) reduced the contents of total dissolved solids (TDS), electrical conductivity (EC), biochemical oxygen demand (BOD 5 ), chemical oxygen demand, total Kjeldahl nitrogen, phosphate ([Formula: see text]), sodium (Na + ), potassium (K + ), calcium (Ca 2+ ), magnesium (Mg 2+ ), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), lead (Pb), zinc (Zn), standard plate count, and most probable number of the municipal wastewater after phytoremediation experiments. The maximum removal of these parameters was obtained at 60 days of the phytoremediation experiments, but the removal rate of these parameters was gradually increased from 15 to 45 days and it was slightly decreased at 60 days. Most contents of Cd, Cu, Fe, Mn and Zn were translocated in the leaves of T. natans, whereas most contents of Cr and Pb were accumulated in the root of T. natans after phytoremediation experiments. The contents of different biochemical components were recorded in the order of total sugar > crude protein > total ash > crude fiber > total fat in T. natans after phytoremediation of municipal wastewater. Therefore, T. natans was found to be effective for the removal of different parameters of municipal wastewater and can be used effectively to reduce the pollution load of municipal wastewater drained from the ASP-based treatment plants.

  14. Changes imposed by pyrolysis, thermal gasification and incineration on composition and phosphorus fertilizer quality of municipal sewage sludge

    DEFF Research Database (Denmark)

    Thomsen, Tobias Pape; Sárossy, Zsuzsa; Ahrenfeldt, Jesper

    2017-01-01

    Fertilizer quality of ash and char from incineration, gasification and pyrolysis of a single municipal sewage sludge sample were investigated by comparing composition and phosphorus (P) plant availability. A process for post oxidation of gasification ash and pyrolysis char was developed and the o......Fertilizer quality of ash and char from incineration, gasification and pyrolysis of a single municipal sewage sludge sample were investigated by comparing composition and phosphorus (P) plant availability. A process for post oxidation of gasification ash and pyrolysis char was developed...... and the oxidized materials were investigated as well. Sequential extraction with full elemental balances of the extracted pools as well as scanning electron microscopy with energy dispersive X-ray spectroscopy were used to investigate the mechanisms driving the observed differences in composition and P plant...... processes and 10–15% in pyrolysis whereas no reduction was observed in incineration processes. The influence on other heavy metals was less pronounced. The plant availability of P in the substrates varied from almost zero to almost 100% of the plant availability of P in the untreated sludge. Post-oxidized...

  15. Effects of land disposal of municipal sewage sludge on fate of nitrates in soil, streambed sediment, and water quality

    Science.gov (United States)

    Tindall, James A.; Lull, Kenneth J.; Gaggiani, Neville G.

    1994-01-01

    the research site, it has been determined that a potentially large source of contamination exists in the soils of the study area owing to increased concentrations of nitrogen, sodium, calcium, magnesium, sulfate, bicarbonate, and chloride because of sewage disposal. Continued monitoring of surface and ground water for nitrogen and the other ions previously mentioned is required to assess long-term effects of municipal sludge disposal on water quality.

  16. Assessment of biogas production in Argentina from co-digestion of sludge and municipal solid waste.

    Science.gov (United States)

    Morero, Betzabet; Vicentin, Rocio; Campanella, Enrique A

    2017-03-01

    In Argentina, there is an important potential to utilize organic waste to generate bioenergy. This work analyzes the environmental impacts and the energetic and economic requirements of the biogas produced by digesting the sewage sludge (SS) produced in a wastewater treatment plant in a medium city in Argentina. The SS is co-digested with the organic fraction of municipal solid waste (OFMSW), and the basis of this study is the life cycle assessment (LCA). The LCA is performed according to ISO 14040-44 using the SimaPro simulator. First, the transport of the raw materials to the biogas plant was defined. Then, the co-digestion and the biogas treatment for final use were evaluated. The co-digestion was improved with glycerol, and the generation of biogas was estimated using the GPS-X software. Two alternatives for the end use of biogas were considered: combined heat and power (CHP) and biomethane generation. For the first, H 2 S and water vapor were removed from the raw biogas stream, and for the second, also CO 2 was removed. The H 2 S removal process was simulated in the SuperPro software by anaerobic biofiltration. The same software was used to simulate the removal of CO 2 absorption-desorption with water as solvent. Finally, the environmental impacts related to the end use of biogas (CHP and biomethane) were evaluated. The environmental, energetic and economic analyses showed that the co-digestion of SS and OFMSW has great potential for reducing the environmental impacts and increasing the economic and energetic value of the substances via the production of biomethane, electricity and, potentially, fertilizer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Possible Applications of Hardening Slurries with Fly Ash from Thermal Treatment of Municipal Sewage Sludge in Environmental Protection Structures

    Science.gov (United States)

    Falacinski, Paweł; Szarek, Łukasz

    2016-06-01

    In Poland, in recent years, there has been a rapid accumulation of sewage sludge - a by-product in the treatment of urban wastewater. This has come about as a result of infrastructure renewal, specifically, the construction of modern sewage treatment plants. The more stringent regulations and strategic goals adopted for modern sewage management have necessitated the application of modern engineering methodology for the disposal of sewage sludge. One approach is incineration. As a consequence, the amount of fly ash resulting from the thermal treatment of municipal sewage sludge has grown significantly. Hence, intensive work is in progress for environmentally safe management of this type of waste. The aim of the experiment was to evaluate the possibility of using the fly ash that results from municipal sewage sludge thermal treatment (SSTT) as an additive to hardening slurries. This type of hardening slurry with various types of additives, e.g. coal combustion products, is used in the construction of cut-off walls in hydraulic structures. The article presents the technological and functional parameters of hardening slurries with an addition of fly ash obtained by SSTT. Moreover, the usefulness of these slurries is analysed on the basis of their basic properties, i.e. density, contractual viscosity, water separation, structural strength, volumetric density, hydraulic conductivity, compressive and tensile strength. The mandated requirements for slurries employed in the construction of cut-off walls in flood embankments are listed as a usefulness criteria. The article presents the potential uses of fly ash from SSTT in hardening slurry technology. It also suggests directions for further research to fully identify other potential uses of this by-product in this field.

  18. Occurrence and fate of PBDE in sewage sludge from municipal waste water treatment plants

    Energy Technology Data Exchange (ETDEWEB)

    Knoth, W.; Mann, W.; Meyer, R.; Nebhuth, J. [Federal Environmental Agency, POP Laboratory, Langen (Germany)

    2004-09-15

    With the rapidly growing use of combustible polymer material, e.g. for IT/TV casings, mattresses, upholstered furniture, the use of flame retardants like polybrominated diphenyl ether (PBDE) has also increased strongly. PBDE are available as three commercial mixtures of BDE congeners named after their principal component: PeBDE, OcBDE and DeBDE. They can release into the environment during their production, use or after disposal and have become ubiquitous. Because of (exponentially) increasing levels of the main congeners of technical Pe- and OcBDE in human blood and milk in Europe and California, the use and the placing on the market of preparations and articles containing these two flame retardants in concentrations >0.1% by mass are prohibited from August 15, 2004 in the European Union4 and in California from the year 2008. The main North American manufacturer of PeBDE flame retardant will voluntarily cease production by the end of 2004. For DeBDE a risk assessment is in progress. Surprising high levels were analysed in blood samples from 155 volunteers in the UK2 and a debromination to more bioavailable Hx- and HpBDE by juvenile carp (cyprinus carpio) following dietary exposure was observed. The objective of this study is to get more information about the actual levels and time trend of PBDE in sewage sludge in Germany and on a possible degradation of DeBDE by photolytic or reductive debromination during waste water treatment process.

  19. Effect of electron beam irradiation on bacterial and Ascaris ova loads and volatile organic compounds in municipal sewage sludge

    International Nuclear Information System (INIS)

    Engohang-Ndong, Jean; Uribe, R.M.; Gregory, Roger; Gangoda, Mahinda; Nickelsen, Mike G.; Loar, Philip

    2015-01-01

    Wastewater treatment plants produce large amounts of biosolids that can be utilized for land applications. However, prior to their use, these biosolids must be treated to eliminate risks of infections and to reduce upsetting odors. In this study, microbiological and chemical analyzes were performed before and after treatment of sewage sludge with 3 MeV of an electron beam accelerator in a pilot processing plant. Thus, we determined that dose 4.5 kGy was required to reduce fecal coliform counts to safe levels for land applications of sludge while, 14.5 kGy was necessary to decrease Ascaris ova counts to safe levels. Furthermore, at low doses, electron beam irradiation showed little effect on the concentrations of volatile organic compounds, while some increase were recorded at high doses. The concentration of dimethyl sulfide was reduced by 50–70% at irradiation doses of 25.7 kGy and 30.7 kGy respectively. By contrast, electron beam irradiation increased dimethyl disulfide concentrations. We also showed that electron beam treatment was less energy-consuming with shorter processing times than conventional techniques used to decontaminate sludge. Hence opening new avenues for large urban agglomerations to save money and time when treating biosolids for land application. - Highlights: • Use of electron beam irradiation for the treatment of municipal sewage sludge. • Irradiation at 4.5 kGy is required to eliminate risks of bacterial infection. • Irradiation at 14.5 kGy is required to eliminate risks of helminth infection. • Electron beam technology is not effective for controlling volatile organic compounds. • Electron beam treatment of sludge is less expensive than traditional techniques

  20. Biodiesel production from wet municipal sludge: evaluation of in situ transesterification using xylene as a cosolvent.

    Science.gov (United States)

    Choi, O K; Song, J S; Cha, D K; Lee, J W

    2014-08-01

    This study proposes a method to produce biodiesel from wet wastewater sludge. Xylene was used as an alternative cosolvent to hexane for transesterification in order to enhance the biodiesel yield from wet wastewater sludge. The water present in the sludge could be separated during transesterification by employing xylene, which has a higher boiling point than water. Xylene enhanced the biodiesel yield up to 8.12%, which was 2.5 times higher than hexane. It was comparable to the maximum biodiesel yield of 9.68% obtained from dried sludge. Xylene could reduce either the reaction time or methanol consumption, when compared to hexane for a similar yield. The fatty acid methyl esters (FAMEs) content of the biodiesel increased approximately two fold by changing the cosolvent from hexane to xylene. The transesterification method using xylene as a cosolvent can be applied effectively and economically for biodiesel recovery from wet wastewater sludge without drying process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Usage of Social Media in City Marketing: A Research on 30 Metropolitan Municipalities in Turkey

    Directory of Open Access Journals (Sweden)

    Niyazi Gümüş

    2017-01-01

    Full Text Available Rapid changes in information and communication technologies cause serious developments in marketing field similar to every sector. In parallel with these developments, the social media channels which appear as Web 2.0 applications have a number of advantages in comparison with traditional media channels. Social media gained a place in marketing activities because of its advantages. Social media is added on instruments in line with these developments that countries benefit in marketing activities for attracting more tourists, investment and becoming prominent against the other cities. Cities intensively benefit from social media because of social media’s properties like reaching the large masses, low marketing cost, interaction, receiving feedbacks rapidly, etc. Within this context, the purpose of this research is to determine the use statuses of social media by metropolitan municipalities as part of city marketing. In accordance with this purpose, official social media accounts of 30 metropolitan municipalities are investigated between the dates of 01/09/2016 and 30/09/2016, then their shares in social media channels are investigated in the context of city marketing.It is observed that two metropolitan municipalities do not have official Facebook accounts, four metropolitan municipalities do not have an official Twitter account as well. Again, it is found that 19 metropolitan municipalities do not have an official Instagram account and 17 metropolitan municipalities do not have official YouTube account. In consequence, it is observed that, our metropolitan municipalities do not benefit from social media effectively for city marketing activities.

  2. Co-composting of hair waste from the tanning industry with de-inking and municipal wastewater sludges.

    Science.gov (United States)

    Barrena, Raquel; Pagans, Estel la; Artola, Adriana; Vázquez, Felícitas; Sánchez, Antoni

    2007-06-01

    Production of waste hair in the leather manufacturing industry is increasing every year due to the adoption of hair-save unhairing techniques, leaving the tanners with the problem of coping with yet another solid by-product. Numerous potential strategies for hair utilisation have been proposed. However, the use of hair waste as agricultural fertiliser is one of its most promising applications due to the high nitrogen content of hair. Agricultural value of hair can be increased by composting. This paper deals with the composting of hair from the unhairing of bovine hide. Results indicated that hair cannot be either composted on its own or co-composted with de-inking sludge, a chemical complementary co-substrate. However, good results were obtained when co-composted with raw sludge from a municipal wastewater treatment plant at hair:raw sludge weight ratios 1:1, 1:2 and, 1:4 in lab scale and pilot plant scale composters. In all cases, a more stable product was achieved at the end of the process. Composting in the pilot plant composter was effectively monitored using Static Respiration Indices determined at process temperature at sampling (SRI(T)) and at 37 degrees C (SRI(37)). Notably, SRI(T) values were more sensitive to changes in the biological activity. In contrast, Respiratory Quotient (RQ) values were not adequate to follow the development of the process.

  3. Diversity Profile of Microbes Associated with Anaerobic Sulfur Oxidation in an Upflow Anaerobic Sludge Blanket Reactor Treating Municipal Sewage

    Science.gov (United States)

    Aida, Azrina A.; Kuroda, Kyohei; Yamamoto, Masamitsu; Nakamura, Akinobu; Hatamoto, Masashi; Yamaguchi, Takashi

    2015-01-01

    We herein analyzed the diversity of microbes involved in anaerobic sulfur oxidation in an upflow anaerobic sludge blanket (UASB) reactor used for treating municipal sewage under low-temperature conditions. Anaerobic sulfur oxidation occurred in the absence of oxygen, with nitrite and nitrate as electron acceptors; however, reactor performance parameters demonstrated that anaerobic conditions were maintained. In order to gain insights into the underlying basis of anaerobic sulfur oxidation, the microbial diversity that exists in the UASB sludge was analyzed comprehensively to determine their identities and contribution to sulfur oxidation. Sludge samples were collected from the UASB reactor over a period of 2 years and used for bacterial 16S rRNA gene-based terminal restriction fragment length polymorphism (T-RFLP) and next-generation sequencing analyses. T-RFLP and sequencing results both showed that microbial community patterns changed markedly from day 537 onwards. Bacteria belonging to the genus Desulforhabdus within the phylum Proteobacteria and uncultured bacteria within the phylum Fusobacteria were the main groups observed during the period of anaerobic sulfur oxidation. Their abundance correlated with temperature, suggesting that these bacterial groups played roles in anaerobic sulfur oxidation in UASB reactors. PMID:25817585

  4. Evaluation of composting as a strategy for managing organic wastes from a municipal market in Nicaragua.

    Science.gov (United States)

    Aulinas Masó, Montserrat; Bonmatí Blasi, August

    2008-07-01

    A pilot-scale study was undertaken to evaluate alternatives to the solid waste management of a Central American municipal market located in Estelí, Nicaragua. The municipal solid waste from the local market is the second largest contributor to the municipal solid waste (MSW) stream. Waste from the market without any previous sorting or treatment is open dumped. The options evaluated in this study were windrow composting, windrow composting with yard waste, bokashi and vermicompost. Significant differences between the properties of composts produced were found; however, all of them reduce the initial waste volume and are potential useful agronomic products for a survival agrarian milieu.

  5. Co-digestion of cultivated microalgae and sewage sludge from municipal waste water treatment.

    Science.gov (United States)

    Olsson, Jesper; Feng, Xin Mei; Ascue, Johnny; Gentili, Francesco G; Shabiimam, M A; Nehrenheim, Emma; Thorin, Eva

    2014-11-01

    In this study two wet microalgae cultures and one dried microalgae culture were co-digested in different proportions with sewage sludge in mesophilic and thermophilic conditions. The aim was to evaluate if the co-digestion could lead to an increased efficiency of methane production compared to digestion of sewage sludge alone. The results showed that co-digestion with both wet and dried microalgae, in certain proportions, increased the biochemical methane potential (BMP) compared with digestion of sewage sludge alone in mesophilic conditions. The BMP was significantly higher than the calculated BMP in many of the mixtures. This synergetic effect was statistically significant in a mixture containing 63% (w/w VS based) undigested sewage sludge and 37% (w/w VS based) wet algae slurry, which produced 23% more methane than observed with undigested sewage sludge alone. The trend was that thermophilic co-digestion of microalgae and undigested sewage sludge did not give the same synergy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Beneficial use of waste nuclear isotopes - 137Cs radiation treatment of municipal sludge and compost

    International Nuclear Information System (INIS)

    Remini, W.C.; Wahlquist, B.J.; Sivinsky, H.D.

    1977-01-01

    For the past several years, the Nuclear Research and Applications Division has been sponsoring, in cooperation with EPA, a program to develop the technology and investigate the potential of using gamma radiation to reduce pathogen levels in sewage sludge. The irradiation source would be cesium-137 which has been extracted from the reactor wastes and diverted to this use. It would be used in this irradiation process until its source strength had decayed to the point that it was no longer effective. At that point, it would be transferred for disposal. This sludge irradiation program is a part of a larger effort to develop beneficial uses of individual isotopes or combinations of isotopes contained in the reactor wastes. Such potential applications include strontium-90 for power generation in remote applications, extraction of platinum family metals to help alleviate demands on foreign supplies, and use of krypton-85 in self-luminous light sources. Sludge irradiation offers what appears to be near-term benefits and has received the major focus in this program. This summary report reviews the progress and current status in the sludge irradiation program. It reviews the background of the national sludge problem and describes how the irradiation process may be applied to this problem. The two major approaches, wet and dry irradiation, are described and their technical and economic potential is discussed. Finally, the status of on-going efforts to experimentally apply irradiation to sludges are summarized and a projected development plan is outlined. (Auth.)

  7. State aid, open access and market size : two cases of FTTH network implementation in Dutch municipalities

    NARCIS (Netherlands)

    Sadowski, B.M.; Rooij, de M.A.J.; Smits, J.M.

    2006-01-01

    The discussion on the EU regulatory framework of 2003 in particular on emerging markets provides for a new dynamic approach towards investment in next generation broadband infrastructure in municipalities. By using the criterion of non-replicable assets, FTTH networks in local municipalities can be

  8. State aid, open access and market size: two cases of FTTH network implementation in Dutch municipalities

    NARCIS (Netherlands)

    Sadowski, B.M.; Rooij, de M.A.J.; Smits, J.M.

    2006-01-01

    The discussion on the EU regulatory framework of 2003 in particular on emerging markets provides for a new dynamic approach towards investment in next generation broadband infrastructure in municipalities. By using the criterion of non-replicable assets, FTTH networks in local municipalities can be

  9. Utilization of municipal sewage sludge as additives for the production of eco-cement

    International Nuclear Information System (INIS)

    Lin, Yiming; Zhou, Shaoqi; Li, Fuzhen; Lin, Yixiao

    2012-01-01

    Highlights: ► The results of X-ray diffraction (XRD) pattern and scanning electron micrograph (SEM) indicated that the major components in the eco-cement clinkers were similar to those in ordinary Portland cement. ► Though the C 2 S phase formation increased with the increase of sewage sludge contents. ► All the eco-cement pastes had a longer initial setting time and final setting time than those of plain cement paste, which increased as the sewage sludge contents in raw meal increased. ► All the eco-cement pastes had lower early flexural strengths and it increased with the increase of sewage sludge contents increased, while the compressive strengths decreased slightly. ► However, it had no significant effect on all the strengths at later ages. - Abstract: The effects of using dried sewage sludge as additive on cement property in the process of clinker burning were investigated in this paper. The eco-cement samples were prepared by adding 0.50–15.0% of dried sewage sludge to unit raw meal, and then the mixtures were burned at 1450 °C for 2 h. The results indicated that the major components in the eco-cement clinkers were similar to those in ordinary Portland cement. Although the C 2 S phase formation increased with the increase of sewage sludge content, it was also found that the microstructure of the mixture containing 15.0% sewage sludge in raw meal was significantly different and that a larger amount of pores were distributed in the clinker. Moreover, all the eco-cement pastes had a longer initial setting time and final setting time than those of plain cement paste, which increased as the sewage sludge content in the raw meal increased. All the eco-cement pastes had lower early flexural strengths, which increased as the sewage sludge content increased, while the compressive strengths decreased slightly. However, this had no significant effect on all the strengths at later stages. Furthermore, the leaching concentrations of all the types of eco

  10. Improving the biogas production performance of municipal waste activated sludge via disperser induced microwave disintegration.

    Science.gov (United States)

    Kavitha, S; Rajesh Banu, J; Vinoth Kumar, J; Rajkumar, M

    2016-10-01

    In this study, the influence of disperser induced microwave pretreatment was investigated to analyze the proficiency of floc disruption on subsequent disintegration and biodegradability process. Initially, the flocs in the sludge was disrupted through disperser at a specific energy input of 25.3kJ/kgTS. The upshot of the microwave disintegration presents that the solids reduction and solubilization of floc disrupted (disperser induced microwave pretreated) sludge was found to be 17.33% and 22% relatively greater than that achieved in microwave pretreated (9.3% and 16%) sludge alone. The biodegradability analysis, affords an evaluation of parameter confidence and correlation determination. The eventual biodegradability of microwave pretreated, and floc disrupted sludges were computed to be 0.15(gCOD/gCOD) and 0.28(gCOD/gCOD), respectively. An economic assessment of this study offers a positive net profit of about 104.8USD/ton of sludge in floc disrupted sample. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Enhancement of aerobic biodegradability potential of municipal waste activated sludge by ultrasonic aided bacterial disintegration.

    Science.gov (United States)

    Kavitha, S; Jessin Brindha, G M; Sally Gloriana, A; Rajashankar, K; Yeom, Ick Tae; Rajesh Banu, J

    2016-01-01

    An investigation was performed to study the influence of ultrasonic aided bacterial disintegration on the aerobic degradability of sludge. In first phase of the study, effective floc disruption was achieved at an ultrasonic specific energy input of 2.45kJ/kg TS with 44.5mg/L of Extracellular Polymeric Substance (EPS) release including 0.035U/mL and 0.025U/mL protease and amylase activity respectively. In second phase, experimental outcomes revealed bacterial disintegration of floc disrupted-sludge showing a maximum solubilization of about 23% and was observed to be superior to bacterially disintegrated (11%) and control (6%), respectively. The result of aerobic biodegradability of ultrasonic aided bacterially pretreated sludge showed volatile solids (VS) degradation of about 40.2%. The kinetic study of aerobic biodegradability through non linear regression modelling reveals that floc disrupted sludge showed better biodegradability with decay constant of about 0.19d(-1) relatively higher than the control (0.14d(-1)) and bacterially disintegrated (0.17d(-1)) sludges. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Separation of Flue-Gas Scrubber Sludge into Marketable Products

    International Nuclear Information System (INIS)

    1998-01-01

    The reduction of sulfur oxides from high sulfur coal burning utility companies has resulted in the production of huge quantities of wet flue-gas desulfurization scrubber sludge. A typical 400 MW power station burning a coal containing 3.5% sulfur by weight and using a limestone absorbent would produce approximately 177,000 tons (dry weight) of scrubber sludge per year. This brownish colored, finely divided material contains calcium sulfite (CaSO 3 · 1/2 H 2 O), calcium sulfate (CaSO 4 · 2H 2 O), unreacted limestone (CaCO 3 ), and various other impurities such as fly-ash and iron oxide particles. The physical separation of the components of scrubber sludge would result in the re-use of this material. The primary use would be conversion to a highly pure synthetic gypsum. This technical report concentrates on the effect of baffle configuration on the separation of calcium sulfite/sulfate from limestone. The position of the baffles as they related to the feed inlet, and the quantity of the baffles were examined. A clean calcium sulfite/sulfate (less than 2.0% limestone by weight) was achieved with the combination of water-only cyclone and horizontally baffled column

  13. A comprehensive substance flow analysis of a municipal wastewater and sludge treatment plant

    DEFF Research Database (Denmark)

    Yoshida, Hiroko; Christensen, Thomas Højlund; Guildal, T.

    2015-01-01

    The fate of total organic carbon, 32 elements (Al, Ag, As, Ba, Be, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, N, Na, Ni, P, Pb, S, Sb, Se, Sn, Sr, Ti, V, and Zn) and 4 groups of organic pollutants (linear alkylbenzene sulfonates, bis(2-ethylhexyl)phthalate, polychlorinated biphenyl...... on the assessment, it is evident that both inorganic and organic elements accumulated in the sewage sludge, with the exception of elements that are highly soluble or degradable by wastewater and sludge treatment processes. The majority of metals and metalloids were further accumulated in the incineration ash, while...

  14. Hydrothermal Liquefaction and Upgrading of Municipal Wastewater Treatment Plant Sludge: A Preliminary Techno-Economic Analysis, Rev.1

    Energy Technology Data Exchange (ETDEWEB)

    Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhu, Yunhua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susanne B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schmidt, Andrew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hallen, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billing, Justin M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Todd R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Samuel P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Maupin, Gary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-01

    A preliminary process model and techno-economic analysis (TEA) was completed for fuel produced from hydrothermal liquefaction (HTL) of sludge waste from a municipal wastewater treatment plant (WWTP) and subsequent biocrude upgrading. The model is adapted from previous work by Jones et al. (2014) for algae HTL, using experimental data generated in fiscal year 2015 (FY15) bench-scale HTL testing of sludge waste streams. Testing was performed on sludge samples received from Metro Vancouver’s Annacis Island WWTP (Vancouver, B.C.) as part of a collaborative project with the Water Environment and Reuse Foundation (WERF). The full set of sludge HTL testing data from this effort will be documented in a separate report to be issued by WERF. This analysis is based on limited testing data and therefore should be considered preliminary. In addition, the testing was conducted with the goal of successful operation, and therefore does not represent an optimized process. Future refinements are necessary to improve the robustness of the model, including a cross-check of modeled biocrude components with the experimental GCMS data and investigation of equipment costs most appropriate at the relatively small scales used here. Environmental sustainability metrics analysis is also needed to understand the broader impact of this technology pathway. The base case scenario for the analysis consists of 10 HTL plants, each processing 100 dry U.S. ton/day (92.4 ton/day on a dry, ash-free basis) of sludge waste and producing 234 barrel per stream day (BPSD) biocrude, feeding into a centralized biocrude upgrading facility that produces 2,020 barrel per standard day of final fuel. This scale was chosen based upon initial wastewater treatment plant data collected by PNNL’s resource assessment team from the EPA’s Clean Watersheds Needs Survey database (EPA 2015a) and a rough estimate of what the potential sludge availability might be within a 100-mile radius. In addition, we received

  15. Effects of additives on the co-pyrolysis of municipal solid waste and paper sludge by using thermogravimetric analysis.

    Science.gov (United States)

    Fang, Shiwen; Yu, Zhaosheng; Lin, Yan; Lin, Yousheng; Fan, Yunlong; Liao, Yanfen; Ma, Xiaoqian

    2016-06-01

    By using thermogravimetric analysis (TGA), the effects of different additives (MgO, Al2O3 and ZnO) on the pyrolysis characteristics and activation energy of municipal solid waste (MSW), paper sludge (PS) and their blends in N2 atmosphere had been investigated in this study. The experiments resulted that these additives were effective in reducing the initial temperature and activation energy. However, not all the additives were beneficial to reduce the residue mass and enhance the index D. For the different ratios of MSW and PS, the same additive even had the different influences. The catalytic effects of additives were not obvious and the pyrolysis became difficult with the increase of the proportion of PS. Based on all the contrast of the pyrolysis characteristics, MgO was the best additive and 70M30P was the best ratio, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Biomethane Production as an Alternative Bioenergy Source from Codigesters Treating Municipal Sludge and Organic Fraction of Municipal Solid Wastes

    Directory of Open Access Journals (Sweden)

    M. Evren Ersahin

    2011-01-01

    Full Text Available Energy recovery potential of a mesophilic co-digester treating OFMSW and primary sludge at an integrated biomethanization plant was investigated based on feasibility study results. Since landfilling is still the main solid waste disposal method in Turkey, land scarcity will become one of the most important obstacles. Restrictions for biodegradable waste disposal to sanitary landfills in EU Landfill Directive and uncontrolled long-term contamination with gas emissions and leachate necessitate alternative management strategies due to rapid increase in MSW production. Moreover, since energy contribution from renewable resources will be required more in the future with increasing oil prices and dwindling supplies of conventional energy sources, the significance of biogas as a renewable fuel has been increased in the last decade. Results indicated that almost 93% of annual total cost can be recovered if 100% renewable energy subsidy is implemented. Besides, considering the potential revenue when replacing transport fuels, about 26 heavy good vehicles or 549 cars may be powered per year by the biogas produced from the proposed biomethanization plant (PE = 100,000; XPS = 61 g TS/PE⋅day; XSS-OFMSW=50 g TS/PE⋅day.

  17. Behaviour of Inorganic Constituents of Municipal Sewage Sludge during Fluidized-Bed Combustion.

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Pohořelý, Michael; Trnka, Otakar

    2007-01-01

    Roč. 61, 3 (2007) , s. 181-185 ISSN 0366-6352 R&D Projects: GA AV ČR(CZ) IAA4072201 Institutional research plan: CEZ:AV0Z40720504 Keywords : sewage sludge * heavy metals * fluidized-bed combustion Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.367, year: 2007

  18. Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge

    DEFF Research Database (Denmark)

    Thomsen, Tobias Pape; Hauggaard-Nielsen, Henrik; Gøbel, Benny

    2017-01-01

    to the mono-sludge ashes, thereby showing the best fertilizer qualities among all assessed materials. It was also found that bottom ashes from the char reactor contained even less heavy metals than cyclone ashes. It is concluded that LT-CFB gasification and co-gasification is a highly effective way to purify...

  19. Sequential pretreatment for cell disintegration of municipal sludge in a neutral Bio-electro-Fenton system.

    Science.gov (United States)

    Yu, Qilin; Jin, Xiaochen; Zhang, Yaobin

    2018-05-15

    Sludge cell disruption was generally considered as the rate-limiting step for the anaerobic digestion of waste activated sludge (WAS). Advanced oxidation processes and bio-electro-chemical systems were recently reported to enhance the hydrolysis of WAS and sludge cell disruption, while the cell-breaking processes of these systems remain unclear yet. In this study, an innovative Bio-electro-Fenton system was developed to pretreat the WAS sequentially with cathode Fenton process and anode anaerobic digestion. Significant cell disruption and dissolution intracellular organics were founded after the treatment. X-ray photoelectron spectroscopy (XPS) analysis and fourier transform infrared spectroscopy (FT-IR) spectra indicated that Gram-negative bacteria were more sensitive to free radicals yielded in cathode to induce a chain reaction that destroyed the lipid-contained outer membrane, while Gram-positive bacteria with thick peptidoglycan layer were liable to be biologically decomposed in the anode. Compared with the oxidation of organic matters in the cathode Fenton, the secretion of enzyme increased in the anode which was beneficial to break down the complex matters (peptidoglycans) into simples that were available for anode oxidation by exoelectrogens. The results also showed a possible prospect for the application of this sequential pretreatment in bio-electro-Fenton systems to disrupt sludge cells and enhance the anaerobic digestion. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Stabilization of heavy metals in municipal sewage sludge by freeze-thaw treatment with a blend of diatomite, FeSO4, and Ca(OH)2.

    Science.gov (United States)

    Wang, Jing; Fu, Rongbing; Xu, Zhen

    2017-08-01

    In this work, the effects of diatomite with 15% FeSO 4 •7H 2 O and 7.5% Ca(OH) 2 on sludge stabilization were investigated using batch leaching tests. The influence of cell rupture caused by freezing and thawing on stabilization was also evaluated. The results indicated that the optimal diatomite percentage was 2%. Cell rupture by freezing and thawing reduced heavy metal leachability, followed by cell death and decrease of organic groups. The concentration of heavy metals in sludge leachate increased after cell rupture, indicating that the heavy metal leachability was reduced after freezing and thawings. Moreover, the stabilization effects were generally improved after freezing and thawing. As compared with the stabilization of the original sludge, the unstable fractions decreased and the residual fractions of the heavy metals increased in the stabilized sludge after cell rupture. This study developed a method to stabilize heavy metals in municipal sewage sludge. Diatomite combined with FeSO 4 ·7H 2 O and Ca(OH) 2 improved the treatment of sewage sludge contaminated by heavy metals. Cell lysis by freeze-thaw treatment reduced the risk of leaching heavy metals caused by cell death and decreased major organic groups in the sludge.

  1. Changes imposed by pyrolysis, thermal gasification and incineration on composition and phosphorus fertilizer quality of municipal sewage sludge.

    Science.gov (United States)

    Thomsen, Tobias Pape; Sárossy, Zsuzsa; Ahrenfeldt, Jesper; Henriksen, Ulrik B; Frandsen, Flemming J; Müller-Stöver, Dorette Sophie

    2017-08-01

    Fertilizer quality of ash and char from incineration, gasification and pyrolysis of a single municipal sewage sludge sample were investigated by comparing composition and phosphorus (P) plant availability. A process for post oxidation of gasification ash and pyrolysis char was developed and the oxidized materials were investigated as well. Sequential extraction with full elemental balances of the extracted pools as well as scanning electron microscopy with energy dispersive X-ray spectroscopy were used to investigate the mechanisms driving the observed differences in composition and P plant availability in a short-term soil incubation study. The compositional changes related mainly to differences in the proximate composition as well as to the release of especially nitrogen, sulfur, cadmium and to some extent, phosphorus (P). The cadmium load per unit of P was reduced with 75-85% in gasification processes and 10-15% in pyrolysis whereas no reduction was observed in incineration processes. The influence on other heavy metals was less pronounced. The plant availability of P in the substrates varied from almost zero to almost 100% of the plant availability of P in the untreated sludge. Post-oxidized slow pyrolysis char was found to be the substrate with the highest P fertilizer value while ash from commercial fluid bed sludge incineration had the lowest P fertilizer quality. The high P fertilizer value in the best substrate is suggested to be a function of several different mechanisms including structural surface changes and improvements in the association of P to especially magnesium, calcium and aluminum. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Molecular characterization of anaerobic sulfur-oxidizing microbial communities in up-flow anaerobic sludge blanket reactor treating municipal sewage.

    Science.gov (United States)

    Aida, Azrina A; Hatamoto, Masashi; Yamamoto, Masamitsu; Ono, Shinya; Nakamura, Akinobu; Takahashi, Masanobu; Yamaguchi, Takashi

    2014-11-01

    A novel wastewater treatment system consisting of an up-flow anaerobic sludge blanket (UASB) reactor and a down-flow hanging sponge (DHS) reactor with sulfur-redox reaction was developed for treatment of municipal sewage under low-temperature conditions. In the UASB reactor, a novel phenomenon of anaerobic sulfur oxidation occurred in the absence of oxygen, nitrite and nitrate as electron acceptors. The microorganisms involved in anaerobic sulfur oxidation have not been elucidated. Therefore, in this study, we studied the microbial communities existing in the UASB reactor that probably enhanced anaerobic sulfur oxidation. Sludge samples collected from the UASB reactor before and after sulfur oxidation were used for cloning and terminal restriction fragment length polymorphism (T-RFLP) analysis of the 16S rRNA genes of the bacterial and archaeal domains. The microbial community structures of bacteria and archaea indicated that the genus Smithella and uncultured bacteria within the phylum Caldiserica were the dominant bacteria groups. Methanosaeta spp. was the dominant group of the domain archaea. The T-RFLP analysis, which was consistent with the cloning results, also yielded characteristic fingerprints for bacterial communities, whereas the archaeal community structure yielded stable microbial community. From these results, it can be presumed that these major bacteria groups, genus Smithella and uncultured bacteria within the phylum Caldiserica, probably play an important role in sulfur oxidation in UASB reactors. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Relationships between stability, maturity, water-extractable organic matter of municipal sewage sludge composts and soil functionality.

    Science.gov (United States)

    Sciubba, Luigi; Cavani, Luciano; Grigatti, Marco; Ciavatta, Claudio; Marzadori, Claudio

    2015-09-01

    Compost capability of restoring or enhancing soil quality depends on several parameters, such as soil characteristics, compost carbon, nitrogen and other nutrient content, heavy metal occurrence, stability and maturity. This study investigated the possibility of relating compost stability and maturity to water-extractable organic matter (WEOM) properties and amendment effect on soil quality. Three composts from municipal sewage sludge and rice husk (AN, from anaerobic wastewater treatment plants; AE, from aerobic ones; MIX, from both anaerobic and aerobic ones) have been analysed and compared to a traditional green waste compost (GM, from green manure, solid waste and urban sewage sludge). To this aim, WEOMs were characterized through chemical analysis; furthermore, compost stability was evaluated through oxygen uptake rate calculation and maturity was estimated through germination index determination, whereas compost impact on soil fertility was studied, in a lab-scale experiment, through indicators as inorganic nitrogen release, soil microbial biomass carbon, basal respiration rate and fluorescein di-acetate hydrolysis. The obtained results indicated that WEOM characterization could be useful to investigate compost stability (which is related to protein and phenol concentrations) and maturity (related to nitrate/ammonium ratio and degree of aromaticity) and then compost impact on soil functionality. Indeed, compost stability resulted inversely related to soil microbial biomass, basal respiration rate and fluorescein di-acetate hydrolysis when the products were applied to the soil.

  4. Co-composting as an oxygen stabilization of an organic fraction of municipal solid waste and industrial sewage sludge.

    Science.gov (United States)

    Milczarek, M; Neczaj, E; Parkitna, K

    2013-01-01

    The purpose of this work is to study the characteristics of the co-composting of municipal solid waste (MSW), sewage sludge, grass and sawdust. Differing proportions of biodegradable waste were investigated through changes of temperature, oxygen consumption, organic matters, moisture content, carbon, nitrogen, C/N ratio as well as heavy metals and pathogen microorganisms content. The present study has shown that addition of MSW above 10% had a negative impact on the composting process. The initial C/N of the mixtures with a higher MSW content was below 18. Lower losses of organic matter occurred during composting for the mixture with the highest addition of MSW. Although studies have shown that composting is a good method for the disposal of organic waste additional research is required in order to optimize the organic and nitrogen compounds degradation during the co-composting process. In conclusion, a 1:4:4:1 mixture of MSW:sewage sludge:grass:sawdust is recommended because it can achieve high temperature as well as the highest organic matter degradation and highest N content in the final composting product. The concentration of heavy and light metals in all composts was within the limits of regulation of the Polish Minister of Agriculture and Rural Development.

  5. The influences of inoculants from municipal sludge and solid waste on compost stability, maturity and enzyme activities during chicken manure composting.

    Science.gov (United States)

    Li, Shuyan; Li, Jijin; Yuan, Jing; Li, Guoxue; Zang, Bing; Li, Yangyang

    2017-07-01

    The aim of this study was to investigate the influence of inoculants on compost stability, maturity and enzyme activities during composting of chicken manure and cornstalk. Two microbial inoculants (originated from aerobic municipal sludge and municipal solid waste, respectively) were used in composting at the rate of 0.3% of initial raw materials (wet weight). No microbial inoculums were added to the control. The experiment was conducted under aerobic conditions for 53 days. The results show that enzyme activity is an important index to comprehensively evaluate the composting stability and maturity. Microbes originated from sludge works best in terms of composting stability and maturity (C:N ratio decreased from 15.5 to 10, and germination index increased to 109%). Microbial inoculums originated from sludge and municipal solid waste extended the time of thermophilic phase for 11 and 7 days, respectively. Microbial inoculums originated from sludge and MSW significantly increased the average of catalase activity (by 15.0% and 12.1%, respectively), urease activity (by 21.5% and 12.2%, respectively) and cellulase activity (by 32.1% and 26.1%, respectively) during composting.

  6. Assessment of the potential of biomethane produced from the French municipal sludge. Synthesis

    International Nuclear Information System (INIS)

    Theobald, Olivier; CHARLOT, Marie-Laure

    2014-09-01

    To achieve the goals of renewable energy production by 23% in 2020 and by 32% in 2030 (Law project on energy transition), the French Government is committed to strongly support all the local renewable energy sectors and in particular the anaerobic digestion. This sector can recycle organic waste into renewable energy while respecting local needs and issues. The objective of this study is to consider the potential of biomethane injectable into the gas grid from Waste Water Treatment Plant (WWTP) sludge in 2020 and in 2050. Wastewater is all sewage from the population but also industrial and commercial activities. The wastewater treatment can be achieved collectively in a wastewater treatment plant or individually (independent sanitation). The organic pollution in wastewater is usually expressed in Population Equivalent. Metropolitan France has 19,521 active wastewater treatment plants (data from portal sanitation, 2014) out of which 85 currently have an anaerobic digestion plant on site for sludge treatment. The entire theoretical methanogenic potential from all the sludge WWTP is 2.13 TWh/year. To estimate the wastewater treatment plants liable to digest sludge, the approach used in this study is to determine the breakeven points of an anaerobic digestion plant installed on different sectors-types of wastewater treatment. The different ways of biogas recovery are sized and compared. It is considered that a case is profitable if its internal rate of return is at least 10 % (compared to a reference case). This approach is characterized by: - A literature review of technical and economic characteristics of the various treatments found at a WWTP including anaerobic digestion and biogas recovery associated, - A return of experience and collect of opinions from various experts in the field of sanitation, - A technical and economic analysis of the various defined cases in relation to a reference case (without anaerobic digestion plant). According to the technical and

  7. Behaviour of pathogenic microorganisms and parasites in biogas production from sewage sludge and municipal wastes

    Energy Technology Data Exchange (ETDEWEB)

    Walter-Matsui, R.; Seipp, M.

    With a grant from VW-Stiftung a project was investigated by the 'Medizinisches Zentrum fuer Hygiene, Philipps-Universitaet, Marburg' and the 'Faculty of Agriculture, Fayum, University Cairo'. The aim was to modify the biogas process to get an optimal amount of biogas and to kill the pathogen bacteria at the same time. The effect of different materials, for example, plant wastes, sewage sludge, cow dung and town refuse and their various amounts of dry matters (2% - 16%) were tested. Also the bactericidal effects of pH, Lactobacilli and higher temperatures were checked. It was found that only a pasteurisation before the fermentation decontaminate the sludge without declining amounts of biogas. It was also proved that the development of Schistosoma eggs was interrupted by the fermentation process.

  8. Effects of elemental sulphur on heavy metal uptake by plants growing on municipal sewage sludge.

    Science.gov (United States)

    Dede, Gulgun; Ozdemir, Saim

    2016-01-15

    In this study experiment was carried out to determine the phytoextraction potential of six plant species (Conium maculatum, Brassica oleraceae var. oleraceae, Brassica juncea, Datura stramonium, Pelargonium hortorum and Conyza canadensis) grown in a sewage sludge medium amended with metal uptake promoters. The solubility of Cu, Cd and Pb was significantly increased with the application of elemental S due to decrease of pH. Faecal coliform number was markedly decreased by addition of elemental sulphur. The extraction of Cu, Cr and Pb from sewage sludge by using B. juncea plant was observed as 65%, 65% and 54% respectively that is statistically similar to EDTA as sulphur. The bioaccumulation factors were found higher (>1) in the plants tested for Cu and Pb like B. juncea. Translocation index (TI) calculated values for Cd and Pb were greater than one (>1) in both C. maculatum and B. oleraceae var. oleraceae. The results cleared that the amendment of sludge with elemental sulphur showed potential to solubilize heavy metals in phytoremediation as much as EDTA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 2: Evaluation of ash materials as phosphorus fertilizer.

    Science.gov (United States)

    Thomsen, Tobias Pape; Hauggaard-Nielsen, Henrik; Gøbel, Benny; Stoholm, Peder; Ahrenfeldt, Jesper; Henriksen, Ulrik B; Müller-Stöver, Dorette Sophie

    2017-08-01

    The study is part 2 of 2 in an investigation of gasification and co-gasification of municipal sewage sludge in low temperature gasifiers. In this work, solid residuals from thermal gasification and co-gasification of municipal sewage sludge were investigated for their potential use as fertilizer. Ashes from five different low temperature circulating fluidized bed (LT-CFB) gasification campaigns including two mono-sludge campaigns, two sludge/straw mixed fuels campaigns and a straw reference campaign were compared. Experiments were conducted on two different LT-CFBs with thermal capacities of 100kW and 6MW, respectively. The assessment included: (i) Elemental composition and recovery of key elements and heavy metals; (ii) content of total carbon (C) and total nitrogen (N); (iii) pH; (iv) water extractability of phosphorus after incubation in soil; and (v) plant phosphorus response measured in a pot experiment with the most promising ash material. Co-gasification of straw and sludge in LT-CFB gasifiers produced ashes with a high content of recalcitrant C, phosphorus (P) and potassium (K), a low content of heavy metals (especially cadmium) and an improved plant P availability compared to the mono-sludge ashes, thereby showing the best fertilizer qualities among all assessed materials. It was also found that bottom ashes from the char reactor contained even less heavy metals than cyclone ashes. It is concluded that LT-CFB gasification and co-gasification is a highly effective way to purify and sanitize sewage sludge for subsequent use in agricultural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Sewage sludge and how to sell it

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, I M

    1977-10-01

    Largo, Florida dries its sludge and sells it as fertilizer for $80 to $169/T. The sludge processing plant capable of turning common sludge into a dry, pelletized soil conditioner was only slightly more expensive than the previously proposed concrete drying beds which would have required disposal of the dried residue. The city's experience in setting up the plant and marketing the finished product is discussed. The true advantage of selling heat-dried sludge is that residents of the surrounding area, knowing the value of the product to their lawns and shrubs, will provide the transportation for the product and the physical labor to spread it over an area wider than most municipalities could afford to own or operate. The current production cost of $140/T is high, but the addition of a sludge prethickener-conditioner process and expected future economies of scale as the volume of sludge treated increases should lower per ton costs.

  11. Fooling the Market? Municipal Yields and Unfunded State Pension Liabilities

    NARCIS (Netherlands)

    Lekniute, Z.; Beetsma, R.M.W.J.; Ponds, Eduard

    2016-01-01

    Existing empirical evidence at the country level exhibits a positive relationship between public indebtedness and the yield on the public debt. Using panel data over the period 2001 – 2014, we show that this relationship holds also for municipal bond yields and the indebtedness of U.S. states.

  12. Elementary analysis and energetic potential of the municipal sewage sludges from the Gdańsk and Kościerzyna WWTPs

    Directory of Open Access Journals (Sweden)

    Ostojski Arkadiusz

    2018-01-01

    Full Text Available This paper aims to present municipal sewage sludge (MSS elementary analysis and energetic potential based on measurement of heat of combustion (higher heating value HHV and calculation of calorific values (lower heating value LHV. The analysis takes into the consideration water content in sewage sludge, at different utilization stages, in wastewater treatment plants in Gdańsk Wschód and Kościerzyna – Pomeranian Voivodeship. The study yielded the following results (in % dry matter: ash 19÷31 %, C - 31÷36 %, H - 5÷6 %, N - 4÷6 %, O - 28÷32 %, S – 1 %. Calorific value of stabilized sludges in Gdańsk was on average 13.8÷15 MJ/kg. In case of sludges not undergoing digestion from Kościerzyna WWTP, the calorific value was at the level of 17.5 MJ/kg. Thus, sewage sludges are good energy carriers. High water content though is the problem, as it lowers the useful effect of heat. There is no alternative for thermal sewage sludge neutralization, which is in conformity with valid Polish National Waste Management Plan (KPGO 2022.

  13. Elementary analysis and energetic potential of the municipal sewage sludges from the Gdańsk and Kościerzyna WWTPs

    Science.gov (United States)

    Ostojski, Arkadiusz

    2018-01-01

    This paper aims to present municipal sewage sludge (MSS) elementary analysis and energetic potential based on measurement of heat of combustion (higher heating value HHV) and calculation of calorific values (lower heating value LHV). The analysis takes into the consideration water content in sewage sludge, at different utilization stages, in wastewater treatment plants in Gdańsk Wschód and Kościerzyna - Pomeranian Voivodeship. The study yielded the following results (in % dry matter): ash 19÷31 %, C - 31÷36 %, H - 5÷6 %, N - 4÷6 %, O - 28÷32 %, S - 1 %. Calorific value of stabilized sludges in Gdańsk was on average 13.8÷15 MJ/kg. In case of sludges not undergoing digestion from Kościerzyna WWTP, the calorific value was at the level of 17.5 MJ/kg. Thus, sewage sludges are good energy carriers. High water content though is the problem, as it lowers the useful effect of heat. There is no alternative for thermal sewage sludge neutralization, which is in conformity with valid Polish National Waste Management Plan (KPGO 2022).

  14. The changing value of the `green' label on the US municipal bond market

    Science.gov (United States)

    Karpf, Andreas; Mandel, Antoine

    2018-01-01

    Green bonds are seen as a key instrument to unlock climate finance. While their volume has grown steadily in recent years, the impact of the `green' label on the bond market is poorly understood. Here, we investigate the differences between the yield term structures of green and conventional bonds in the US municipal bond market. We show that, although returns on conventional bonds are on average higher than for green bonds, the differences can largely be explained by the fundamental properties of the bonds. Historically, green bonds have been penalized on the municipal market, being traded at lower prices and higher yields than expected by their credit profiles. In recent years, however, the credit quality of municipal green bonds has increased and the premium turned positive. Green bonds are thus becoming an increasingly attractive investment, with scope to bridge the climate finance gap for mitigation and adaptation.

  15. Composting sewage sludge

    International Nuclear Information System (INIS)

    Epstein, E.

    1979-01-01

    Sewage sludge is predominantly organic matter containing domestic and industrial wastes. The inefficiency of the waste water treatment to destroy pathogens and stabilization of odor-producing volatile organic compounds necessitates further treatment before sludge can be used as a soil amendment or fertilizer. Composting, which is the rapid biological decomposition of the sludge organic matter is an excellent method of sludge stabilization. During the process, volatile organics are decomposed and many of the pathogens destoyed. The low cost of the process and its flexibility with respect to labor and capital makes the system highly attractive to municipalities. A major problem facing large urban waste water treatment facilities is the distribution or marketing. The light weight of the material, expensive hauling costs, and low fertilizer value reduce its attractiveness to the agricultural sector. Thus, the greatest market is for horticultural purposes, sod, nurseries, greenhouses, parks, and reclamation areas. The major potential benefits of irradiating compost as a means of further disinfection are: (1) elimination of any health hazard; (2) increase of market potential, i.e., providing more market outlets to distribute the material; (3) compliance with state and federal health regulations; and (4) enhancement of the economics of composting as a result of utilizing compost in speciality products commanding a higher value

  16. Removal of Nitrate and Phosphate from Municipal Wastewater Sludge by Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda

    Directory of Open Access Journals (Sweden)

    Jalal K.C.A

    2011-12-01

    Full Text Available Nitrate and phosphorus in wastewater contribute to health and environmental threats as they are linked to illnesses as well as ecosystem disruption via algal blooms in contaminated water bodies. Based on above perspectives a comparative study was conducted on three local freshwater microalgae:Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda to evaluate their effects on nitrate and phosphorus removal from municipal wastewater sludge (MWS. Algae performance in removing nitrate and phosphorus was evaluated by measuring nitrate and phosphorus content of MWS incubated with the strains for 7 days. Instantaneous readings were taken every 48 hours to determine periodic levels of the nutrients phosphate and nitrate. BOD5 was also evaluated to identify the strain with the most robust growth that would demand for oxygen the most in the dark. Spirulina platensis was shown as the most efficient microalgae to reduce nitrate in MWS and the best-growing among the three strains, while Chlorella vulgaris removed phosphorus the most effectively. Thus Spirulina and Chlorella could be potential candidates by showing their intrinsic merit for the reduction of phosphate and nitrate in wastewater treatment.ABSTRAK: Nitrat dan fosforus dalam air sisa menggugat kesihatan dan mengancam alam sekitar memandangkan ia berkait dengan penyakit-penyakit serta gangguan terhadap ekosistem melalui pembiakan alga dalam air yang tercemar. Berdasarkan perspektif di atas, satu kajian perbandingan telah dijalankan terhadap tiga mikro alga air tawar tempatan : Chlorella vulgaris, Spirulina platensis dan Scenedesmus quadricauda untuk dinilai kesannya terhadap penyingkiran nitrat dan fosforus dari enap cemar air sisa bandaran (municipal wastewater sludge (MWS. Kebolehan alga dalam penyingkiran nitrat dan fosforus dikaji dengan menyukat kandungan nitrat dan fosforus dalam MWS yang dieramkan dengan strain ini selama 7 hari. Bacaan serta-merta diambil setiap 48 jam untuk

  17. PLACE MARKETING AND RURAL MUNICIPALITIES IN NORTHERN SWEDEN: A CONTENT ANALYSIS OF MUNICIPAL HOMEPAGES

    OpenAIRE

    Olga Rauhut Kompaniets; Daniel Rauhut

    2013-01-01

    The place marketing concept is one of the most popular concepts used in the analysis and promotion of countries, regions, cities and towns. The intensification of competition for investment, tourism and human resources among European cities and towns has increased the importance of being unique. Most studies on place marketing focus on unique selling points and thus on brands of already extensively ‘marketed’ countries, national capitals and other large metropolitan areas, while the rural tow...

  18. Research on sludge-fly ash ceramic particles (SFCP) for synthetic and municipal wastewater treatment in biological aerated filter (BAF).

    Science.gov (United States)

    Zhao, Yaqin; Yue, Qinyan; Li, Renbo; Yue, Min; Han, Shuxin; Gao, Baoyu; Li, Qian; Yu, Hui

    2009-11-01

    Sludge-fly ash ceramic particles (SFCP) and clay ceramic particles (CCP) were employed in two lab-scale up-flow biological aerated filters (BAF) for wastewater treatment to investigate the availability of SFCP used as biofilm support compared with CCP. For synthetic wastewater, under the selected hydraulic retention times (HRT) of 1.5, 0.75 and 0.37 h, respectively, the removal efficiencies of chemical oxygen demand (COD(Cr)) and ammonium nitrogen (NH(4)(+)-N) in SFCP reactor were all higher than those of CCP reactor all through the media height. Moreover, better capabilities responding to loading shock and faster recovery after short intermittence were observed in the SFCP reactor compared with the CCP reactor. For municipal wastewater treatment, which was carried out under HRT of 0.75 h, air-liquid ratio of 7.5 and backwashing period of 48 h, the SFCP reactor also performed better than the CCP reactor, especially for the removal of NH(4)(+)-N.

  19. Modeling the pH-mediated extraction of ionizable organic contaminants to improve the quality of municipal sewage sludge destined for land application

    International Nuclear Information System (INIS)

    Venkatesan, Arjun K.; Halden, Rolf U.

    2016-01-01

    A model was developed to assess the impact of adding acids and bases to processed municipal sewage sludge (MSS) to mobilize contaminants, facilitating their removal from sludge by flushing prior to land application. Among 312 organic contaminants documented to occur in U.S. MSS, 71 or 23% were identified as ionizable organic contaminants (IOCs), contributing a disproportionately large fraction of 82% of the total mass of sludge-borne contaminants. Detected IOCs included 57 pharmaceuticals and personal care products, 12 perfluorinated compounds, one surfactant and one pesticide. Annually, about 2000 t of IOCs were estimated to be released to U.S. soils via land-application of MSS. A partitioning model developed to assess the impact of pH on hydrophobic sorption revealed that between 36 and 85% of the mass of individual classes of IOCs potentially could be desorbed from MSS via pH adjustment and flushing. Thus, modeling results suggest that a sequential pH treatment [acidic (~ pH 2) followed by basic (~ pH 12) treatment] has the potential to reduce the burden of harmful IOCs in MSS applied on U.S. land by up to 40 ± 16 t annually. This approach may serve as a cost-effective treatment process that can be implemented easily in existing sludge treatment infrastructure in the U.S. and worldwide, serving to significantly improve the quality of MSS destined for land application. - Highlights: • Sorption model predicts the leachability of ionizable organics from sludge. • Ionic organics make up 82% of total contaminant mass in U.S. sludge. • 36–85% of ionic organic pollutants are removable by pH treatment. • Proposed sludge treatment promises cost-effective risk reduction.

  20. Modeling the pH-mediated extraction of ionizable organic contaminants to improve the quality of municipal sewage sludge destined for land application

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesan, Arjun K.; Halden, Rolf U., E-mail: halden@asu.edu

    2016-04-15

    A model was developed to assess the impact of adding acids and bases to processed municipal sewage sludge (MSS) to mobilize contaminants, facilitating their removal from sludge by flushing prior to land application. Among 312 organic contaminants documented to occur in U.S. MSS, 71 or 23% were identified as ionizable organic contaminants (IOCs), contributing a disproportionately large fraction of 82% of the total mass of sludge-borne contaminants. Detected IOCs included 57 pharmaceuticals and personal care products, 12 perfluorinated compounds, one surfactant and one pesticide. Annually, about 2000 t of IOCs were estimated to be released to U.S. soils via land-application of MSS. A partitioning model developed to assess the impact of pH on hydrophobic sorption revealed that between 36 and 85% of the mass of individual classes of IOCs potentially could be desorbed from MSS via pH adjustment and flushing. Thus, modeling results suggest that a sequential pH treatment [acidic (~ pH 2) followed by basic (~ pH 12) treatment] has the potential to reduce the burden of harmful IOCs in MSS applied on U.S. land by up to 40 ± 16 t annually. This approach may serve as a cost-effective treatment process that can be implemented easily in existing sludge treatment infrastructure in the U.S. and worldwide, serving to significantly improve the quality of MSS destined for land application. - Highlights: • Sorption model predicts the leachability of ionizable organics from sludge. • Ionic organics make up 82% of total contaminant mass in U.S. sludge. • 36–85% of ionic organic pollutants are removable by pH treatment. • Proposed sludge treatment promises cost-effective risk reduction.

  1. Marketing Strategies and Students' Enrolment in Private Secondary Schools in Calabar Municipality, Cross River State, Nigeria

    Science.gov (United States)

    Uchendu, Chika C.; Nwafor, Innocent A.; Nwaneri, Mary G.

    2015-01-01

    The study investigated marketing strategies and students' enrolment in private secondary schools in Calabar Municipality, Cross River State. One research question was raised and two null hypotheses formulated to guide the study. Thirty two (32) school administrators in 32 private secondary schools in the study area constitute the study population…

  2. Microwave and thermal pretreatment as methods for increasing the biogas potential of secondary sludge from municipal wastewater treatment plants

    DEFF Research Database (Denmark)

    Kuglarz, Mariusz; Karakashev, Dimitar Borisov; Angelidaki, Irini

    2013-01-01

    In the present study, the sludge was pretreated with microwave irradiation and low-temperature thermal method, both conducted under the same temperature range (30–100°C). Microwave pretreatment was found to be superior over the thermal treatment with respect to sludge solubilization and biogas pr...... experiments indicated that pre-treated sludge (microwave irradiation: 900W, temperature: 60–70°C) gave 35% more methane, compared to untreated sludge. Moreover, the results of this study clearly demonstrated that microwave pretreated sludge showed better degree of sanitation....

  3. [Improvement of municipal sewage sludge dewaterability by bioleaching: a pilot-scale study with sequence batch reaction model].

    Science.gov (United States)

    Liu, Fen-Wu; Zhou, Li-Xiang; Zhou, Jun; Jiang, Feng; Wang, Dian-Zhan

    2011-07-01

    To observe the bioleaching effect on sewage sludge dewaterability, three consecutive batch bioleaching experiments were conducted through a bioleaching bio-reactor with 700 L of working volume. Subsequently, the bioleached sludge was dewatered by using chamber filter press. The results show that the 1st batch bioleaching process can be finished within 90 hours if the aeration amount was 1.2 m3/h with the 1: 15 mixing ratio of bioleached sludge to raw sludge. The pH of sludge declines from initial 6.11 to 2.33 while ORP increased from initial -134 mV to finial 507 mV. The specific resistance to filtration (SRF) of the tested sludge was decreased from original 1.00 x 10(13) m/kg to final 0.09 x 10(13) m/kg after bioleaching. For the subsequent two batch trials, the bioleaching process can be finished in 40 hours and 46 hours, respectively. Likewise, sludge SRF is also significantly decreased to 0.19 x 10(13) m/kg and 0.36 x 10(13) m/kg if the mixing ratio of bioleached sludge to fresh sludge is 1:1 although the microbial nutrient substance dosage is reduced by 25% and 50% for 2nd, and 3rd batch experiments, respectively. The harvested bioleached sludge from three batch trails is dewatered by chamber filter press with 0.3-0.4 MPa working pressure for 2 hours. It is found that the moisture of dewatered sludge cake can be reduced to 58%, and that the dewatered sludge cake is of khaki appearance and didn't emit any offensive odor. In addition, it is also observes that sludge organic matter only changed a bit from 52.9% to 48.0%, but 58% of sludge-borne Cu and 88% of sludge-borne Zn can be removed from sludge by bioleaching process. Therefore, dual goals for sludge-borne heavy metal removal and sludge dewatering of high efficiency can be achieved simultaneously through the approach mentioned above. Therefore, bioleaching technique is of great engineering application for the treatment of sewage sludge.

  4. Municipalities and opening up of energy markets; Les municipalites et l'ouverture des marches energetiques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The opening of energy markets in Europe is modifying deeply the general framework of economic activity, modes of organisation and ways of thinking. The energy future in Europe is being determined under the influence of Community directives relating to electricity and to gas. It is also being moulded by national legislation, which is being progressively put into place in different countries of the European Union and in other European countries such as those of central Europe. These will affect the conditions under which policies for energy efficiency, for the development of renewable energy and for combating climate change are to be implemented. The liberalization of energy markets is a new and highly significant element in the European energy scene and municipalities are making a constructive contribution to this process. About 160 representatives of municipalities from 19 different European countries met at the Energie-Cites Seminar in Barcelona in order to become better informed, to exchange opinions and to debate the consequences at their level of the opening of energy markets. As a consequence they have asked themselves questions and exchanged ideas in relation with their respective situations regarding energy planning, production, distribution, and the role of population motivative. The seminar is organized around one round table about the threats and the opportunities of the opening up of energy markets, and three sessions about: what is going to change for the municipality as energy consumer, what is going to change for the municipality as energy producer, distributor and regulator-developer, and what is going to change for the municipality as motivative. (J.S.)

  5. A critical review of the bioavailability and impacts of heavy metals in municipal solid waste composts compared to sewage sludge.

    Science.gov (United States)

    Smith, Stephen R

    2009-01-01

    The content, behaviour and significance of heavy metals in composted waste materials is important from two potentially conflicting aspects of environmental legislation in terms of: (a) defining end-of-waste criteria and increasing recycling of composted residuals on land and (b) protecting soil quality by preventing contamination. This review examines the effects of heavy metals in compost and amended soil as a basis for achieving a practical and sustainable balance between these different policy objectives, with particular emphasis on agricultural application. All types of municipal solid waste (MSW) compost contain more heavy metals than the background concentrations present in soil and will increase their contents in amended soil. Total concentrations of heavy metals in source-segregated and greenwaste compost are typically below UK PAS100 limits and mechanical segregated material can also comply with the metal limits in UK PAS100, although this is likely to be more challenging. Zinc and Pb are numerically the elements present in the largest amounts in MSW-compost. Lead is the most limiting element to use of mechanically-segregated compost in domestic gardens, but concentrations are typically below risk-based thresholds that protect human health. Composted residuals derived from MSW and greenwaste have a high affinity for binding heavy metals. There is general consensus in the scientific literature that aerobic composting processes increase the complexation of heavy metals in organic waste residuals, and that metals are strongly bound to the compost matrix and organic matter, limiting their solubility and potential bioavailability in soil. Lead is the most strongly bound element and Ni the weakest, with Zn, Cu and Cd showing intermediate sorption characteristics. The strong metal sorption properties of compost produced from MSW or sewage sludge have important benefits for the remediation of metal contaminated industrial and urban soils. Compost and sewage sludge

  6. Phylogenetic comparison of the methanogenic communities from an acidic, oligotrophic fen and an anaerobic digester treating municipal wastewater sludge.

    Science.gov (United States)

    Steinberg, Lisa M; Regan, John M

    2008-11-01

    Methanogens play a critical role in the decomposition of organics under anaerobic conditions. The methanogenic consortia in saturated wetland soils are often subjected to large temperature fluctuations and acidic conditions, imposing a selective pressure for psychro- and acidotolerant community members; however, methanogenic communities in engineered digesters are frequently maintained within a narrow range of mesophilic and circumneutral conditions to retain system stability. To investigate the hypothesis that these two disparate environments have distinct methanogenic communities, the methanogens in an oligotrophic acidic fen and a mesophilic anaerobic digester treating municipal wastewater sludge were characterized by creating clone libraries for the 16S rRNA and methyl coenzyme M reductase alpha subunit (mcrA) genes. A quantitative framework was developed to assess the differences between these two communities by calculating the average sequence similarity for 16S rRNA genes and mcrA within a genus and family using sequences of isolated and characterized methanogens within the approved methanogen taxonomy. The average sequence similarities for 16S rRNA genes within a genus and family were 96.0 and 93.5%, respectively, and the average sequence similarities for mcrA within a genus and family were 88.9 and 79%, respectively. The clone libraries of the bog and digester environments showed no overlap at the species level and almost no overlap at the family level. Both libraries were dominated by clones related to uncultured methanogen groups within the Methanomicrobiales, although members of the Methanosarcinales and Methanobacteriales were also found in both libraries. Diversity indices for the 16S rRNA gene library of the bog and both mcrA libraries were similar, but these indices indicated much lower diversity in the 16S digester library than in the other three libraries.

  7. Effects of land disposal of municipal sewage sludge on soil, streambed sediment, and ground- and surface-water quality at a site near Denver, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Gaggiani, N.G.

    1991-01-01

    The report describes the effects of burial and land application of municipal sewage sludge on soil and streambed sediment and water quality in the underlying aquifers and surface water within and around the Lowry sewage-sludge-disposal area. The existing ground-water observation-well network at the disposal area was expanded for the study. Surface-water-sampling sites were selected so that runoff could be sampled from intense rainstorms or snowmelt. The sampling frequency for ground-water and surface-water runoff was changed from yearly to quarterly, and soil samples were collected. Four years of data were collected from 1984 to 1987 during the expanded monitoring program at the Lowry sewage-sludge-disposal area. These data, in addition to the data collected by the U.S. Geological Survey from 1981 to 1983, were used to determine effects of sewage-sludge-disposal on soil and streambed sediment and surface- and ground-water quality at the disposal area.

  8. Effect of municipal solid waste compost and sewage sludge on yield and heavy metal accumulation in soil and black cumin (Nigella sativa L.

    Directory of Open Access Journals (Sweden)

    F. Akbarnejad

    2016-04-01

    Full Text Available In order to investigate the effect of municipal solid waste (MSw compost and sewage sludge (SS on yield and concentration of heavy metals in soil and black cumin (Nigella sativa L. an experiment with MSW compost at 0, 15, 30 t.ha-1 (C0, C15 and C30 and sewage sludge at 0, 15, 30 t.ha-1 (S0, S15 and S30 in a factorial experiment based on completely randomized design with three replications was conducted in greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. Results showed that MSW compost and SS had significant effects on plant dry matter. Increasing the amounts of SS increased dry matter of plant. But increasing MSW compost from 15 to 30 t.ha-1 was decreased in dry matter. The Effect of MSW compost and SS on concentration of heavy metals (Ni and Pb in plant except Cd was significant. Addition of MSW compost and sewage sludge increased availability of Pb, Ni and Cd in soil. But effect of MSW compost and sewage sludge on Cd availability was not significant. Results showed that the amounts of Ni exceed the standard limits in dry matter. Therefore in use of organic wastes for medicinal plants we should be careful..

  9. Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 1: Process performance and gas product characterization

    DEFF Research Database (Denmark)

    Thomsen, Tobias Pape; Sárossy, Zsuzsa; Gøbel, Benny

    2017-01-01

    Results from five experimental campaigns with Low Temperature Circulating Fluidized Bed (LT-CFB) gasification of straw and/or municipal sewage sludge (MSS) from three different Danish municipal waste water treatment plants in pilot and demonstration scale are analyzed and compared. The gasification...... process is characterized with respect to process stability, process performance and gas product characteristics. All experimental campaigns were conducted at maximum temperatures below 750°C, with air equivalence ratios around 0.12 and with pure silica sand as start-up bed material. A total of 8600kg...... particles in the system. Co-gasification of MSS with sufficient amounts of cereal straw was found to be an effective way to mitigate these issues as well as eliminate thermal MSS drying requirements. Characterization of gas products and process performance showed that even though gas composition varied...

  10. Ozonation and Thermal Pre-Treatment of Municipal Sewage Sludge-Implications for Toxicity and Methane Potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    2013-01-01

    The aim of this study was to determine effects on methane potential and overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 degrees C). In general both treatments produced increased methane potential. Thermal treatment...... by ozone treatment and digestion. No statistical significant reduction in concentrations of included pharmaceuticals could be observed....

  11. Assessment of microbial viability in municipal sludge following ultrasound and microwave pretreatments and resulting impacts on the efficiency of anaerobic sludge digestion.

    Science.gov (United States)

    Cella, Monica Angela; Akgul, Deniz; Eskicioglu, Cigdem

    2016-03-01

    A range of ultrasonication (US) and microwave irradiation (MW) sludge pretreatments were compared to determine the extent of cellular destruction in micro-organisms within secondary sludge and how this cellular destruction translated to anaerobic digestion (AD). Cellular lysis/inactivation was measured using two microbial viability assays, (1) Syto 16® Green and Sytox® Orange counter-assay to discern the integrity of cellular membranes and (2) a fluorescein diacetate assay to understand relative enzymatic activity. A range of MW intensities (2.17-6.48 kJ/g total solids or TS, coinciding temperatures of 60-160 °C) were selected for comparison via viability assays; a range of corresponding US intensities (2.37-27.71 kJ/g TS, coinciding sonication times of 10-60 min at different amplitudes) were also compared to this MW range. The MW pretreatment of thickened waste activated sludge (tWAS) caused fourfold to fivefold greater cell death than non-pretreated and US-pretreated tWAS. The greatest microbial destruction occurred at MW intensities greater than 2.62 kJ/g TS of sludge, after which increased energy input via MW did not appear to cause greater microbial death. In addition, the optimal MW pretreatment (80 °C, 2.62 kJ/g TS) and corresponding US pretreatment (10 min, 60 % amplitude, 2.37 kJ/g TS) were administered to the tWAS of a mixed sludge and fed to anaerobic digesters over sludge retention times (SRTs) of 20, 14, and 7 days to compare effects of feed pretreatment on AD efficiency. The digester utilizing MW-pretreated tWAS (80 °C, 2.62 kJ/g TS) had the greatest fecal coliform removal (73.4 and 69.8 % reduction, respectively), greatest solids removal (44.2 % TS reduction), and highest overall methane production (248.2 L CH4/kg volatile solids) at 14- and 7-day SRTs. However, despite the fourfold to fivefold increases in cell death upon pretreatment, improvements from the digester fed MW-pretreated sludge were marginal (i.e., increases in efficiency of less

  12. Disposal Situation of Sewage Sludge from Municipal Wastewater Treatment Plants (WWTPs) and Assessment of the Ecological Risk of Heavy Metals for Its Land Use in Shanxi, China.

    Science.gov (United States)

    Duan, Baoling; Zhang, Wuping; Zheng, Haixia; Wu, Chunyan; Zhang, Qiang; Bu, Yushan

    2017-07-21

    Land use of sewage sludge is the primary disposal method in Shanxi, accounting for 42.66% of all. To determine the ecological risk of heavy metals in sewage sludge, contents of seven heavy metals in sewage sludge from 9 municipal waste water treatment plants (WWTPs) that had the highest application for land use were determined. The order of the measured concentrations was: Zn > Cr > Cu > Ni > Pb > As > Cd, and all heavy metals contents were within the threshold limit values of the Chinese Control Standards for Pollutants in Sludge from Agriculture Use (GB4284-84). Four indices were used to assess the pollution and the ecological risk of heavy metals. By the mean values of the geoaccumulation index (I geo ), heavy metals were ranked in the following order: Cd > Zn > Cu > As > Cr > Ni > Pb. The values showed that the pollution of Zn in station 3 and Cd in station 1, 2, 3, 4, 8 and 9 were heavily; Cu in station 8 and 9, Zn in station 1, 2, 4, 8 and 9 and Cd in station 5 and 7 were moderately to heavily, and the accumulation of other heavy metals were not significant. The single-factor pollution index (PI) suggested that none of the stations had heavy metals contamination, except for Cu in station 9, Zn in station 3 and 8, and Cd in station 1 and 9, which were at a moderate level. According to the results of the Nemerow's synthetic pollution index (PN), sewage sludge from all stations was safe for land use with respect to heavy metals contamination, except for stations 3, 8 and 9, which were at the warning line. The monomial potential ecological risk coefficient (Eri) revealed that heavy metals ecological risks in most stations were low. However, station 9 had a moderate risk for Cu; station 6 had a moderate risk, stations 5 and 7 had high risk, other stations had very high risk for Cd. According to the results of the potential ecological risk index (RI), station 1, 8 and 9 had high risk; station 2, 3, 4, 5 and 7 had a moderate risk, and station 6 had a low risk. The

  13. Disposal Situation of Sewage Sludge from Municipal Wastewater Treatment Plants (WWTPs and Assessment of the Ecological Risk of Heavy Metals for Its Land Use in Shanxi, China

    Directory of Open Access Journals (Sweden)

    Baoling Duan

    2017-07-01

    Full Text Available Land use of sewage sludge is the primary disposal method in Shanxi, accounting for 42.66% of all. To determine the ecological risk of heavy metals in sewage sludge, contents of seven heavy metals in sewage sludge from 9 municipal waste water treatment plants (WWTPs that had the highest application for land use were determined. The order of the measured concentrations was: Zn > Cr > Cu > Ni > Pb > As > Cd, and all heavy metals contents were within the threshold limit values of the Chinese Control Standards for Pollutants in Sludge from Agriculture Use (GB4284-84. Four indices were used to assess the pollution and the ecological risk of heavy metals. By the mean values of the geoaccumulation index (Igeo, heavy metals were ranked in the following order: Cd > Zn > Cu > As > Cr > Ni > Pb. The values showed that the pollution of Zn in station 3 and Cd in station 1, 2, 3, 4, 8 and 9 were heavily; Cu in station 8 and 9, Zn in station 1, 2, 4, 8 and 9 and Cd in station 5 and 7 were moderately to heavily, and the accumulation of other heavy metals were not significant. The single-factor pollution index (PI suggested that none of the stations had heavy metals contamination, except for Cu in station 9, Zn in station 3 and 8, and Cd in station 1 and 9, which were at a moderate level. According to the results of the Nemerow’s synthetic pollution index (PN, sewage sludge from all stations was safe for land use with respect to heavy metals contamination, except for stations 3, 8 and 9, which were at the warning line. The monomial potential ecological risk coefficient (Eri revealed that heavy metals ecological risks in most stations were low. However, station 9 had a moderate risk for Cu; station 6 had a moderate risk, stations 5 and 7 had high risk, other stations had very high risk for Cd. According to the results of the potential ecological risk index (RI, station 1, 8 and 9 had high risk; station 2, 3, 4, 5 and 7 had a moderate risk, and station 6 had a

  14. Prevention of PCDD/Fs emission from a municipal wastewater sludge incinerator through enhanced control of copper aerosol

    Directory of Open Access Journals (Sweden)

    Peña, E.

    2012-10-01

    Full Text Available Municipal wastewater sludge incineration (MWSI leads to products of incomplete combustion, including chlorinated species such as dioxins and furans (PCDD/Fs. Other pollutants, such as heavy metals (HM, are released too as a consequence of feed traces, which depend on the specific activities of each area. The main aim of this work is to determine whether the early separation of the potential catalysts on the PCDD/Fs formation –HM as copper or zinc– offers a promising way to prevent the emission of these trace pollutants, considering that the current end-of-pipe measures don’t ensure their stable emission. Experimental results cover the size distributed target metal contents along the incineration line. These results show a high concentration of copper in the most penetrating aerosol size range of the electrostatic precipitator (0.6 μm - 1.0 μm, and how low emission values of both, total and metallic aerosol (mass basis, are compatible with irregular and unexplained outliers of PCDD/Fs emission.

    La incineración de lodos de aguas residuales urbanas acarrea la formación de compuestos derivados de combustiones incompletas, incluyendo especies cloradas como dioxinas y furanos (PCDD/Fs. Otros contaminantes, como metales pesados, se emiten como consecuencia de las trazas del lodo, las cuales dependen de las actividades del entorno. El objetivo principal es determinar si la separación de catalizadores potenciales en reacciones de formación de PCDD/Fs (cobre o zinc puede abrir vías para prevenir la emisión de contaminantes traza, considerando que ninguna de las técnicas de prevención actuales aseguran emisiones estables de metales pesados o PCDD/Fs. Se determinan concentraciones de metales pesados segregados por tamaño de partícula a lo largo de la línea de incineración. Los resultados muestran concentraciones elevadas de cobre en el aerosol de máxima penetración del electrofiltro (0,6 μm - 1,0 μm, y cómo concentraciones

  15. Tests in excess sludge minimization through cell membrane break-up by means of ozone at a municipal sewage treatment plant; Versuche zur Ueberschussschlamm-Minimierung durch Zellaufschluss mit Ozon auf einer kommunalen Klaeranlage

    Energy Technology Data Exchange (ETDEWEB)

    Ried, A.; Peters, B. [WEDECO Umweltdienstleistungen GmbH, Herford (Germany)

    1999-07-01

    Disposing of sewage sludge involves high cost. Therfore, processes to reduce sewage sludge are more and more in demand. One such process is the treatment with ozone. The company WEDESCO GmbH is also concerned with ozonification of sewage sludge and carries out tests on a technical scale at a municipal sewage treatment plant. The objective is to reduce the amount of sewage sludge by approximately 50 %, corresponding, in the present case, to the organic sludge portion. (orig.) [German] Da die Entsorgung dieses Klaerschlamms hohe Kosten verursacht, gewinnen Verfahren zur Klaerschlammreduzierung zunehmend an Bedeutung. Eine Moeglichkeit der Reduzierung des Klaerschlamms besteht in der Behandlung mit Ozon. Auch die WEDECO GmbH befasst sich mit der Ozonung von Klaerschlamm und fuehrt Versuche im grosstechnischen Massstab auf einer kommunalen Klaeranlage durch. Ziel dieser Versuche ist es, den anfallenden Klaerschlamm um ca. 50% zu reduzieren, was in diesem Anwendungsfall dem organischen Anteil des Schlamms entspricht. (orig.)

  16. New process controls in the co-fermentation of organic waste and municipal sewage sludge; Neue Verfahrensfuehrungen bei der Co-Vergaerung von Bioabfaellen und kommunalen Klaerschlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Schaepers, D.; Schierholt, M.; Buer, T.; Risse, H. [Technische Hochschule Aachen (DE). Inst. fuer Siedlungswasserwirtschaft (ISA)

    1999-07-01

    For the co-fermentation of organic waste and sewage sludge in digester towers at municipal sewage treatment plant, mainly single-stage processes have so far been studied or are in use in part. Within the framework of a project sponsored by the foundation Oswald-Schulze-Stiftung, the use of a two-stage mode of operation (thermophilic/mesophilic) for co-fermenting organic waste and sewage sludge was investigated. By adding organic waste to the digester content, biogas production per reactor volume was more than doubled in comparison with exclusive sewage sludge fermentation. Because of the thermophilic stage for the conditioning of organic waste, specific biogas yield for an organic load of 1.5 kg organic dry residue TR/m{sup 3*}d was slightly enhanced in comparison with single-stage co-fermentation. (orig.) [German] Zur Co-Vergaerung von Bioabfaellen und Klaerschlamm in Faultuermen kommunaler Klaeranlagen werden bislang hauptsaechlich einstufige Verfahren untersucht und teilweise eingesetzt. Im Rahmen eines von der Oswald-Schulze-Stiftung gefoerderten Projektes wurde der Einsatz einer 2-stufigen Betriebsweise (thermophil/mesophil) bei der Co-Vergaerung von Bioabfaellen und Klaerschlamm untersucht. Die Biogasproduktion pro Reaktorvolumen konnte durch die Zugabe von Bioabfall in die Faulbehaelter gegenueber der reinen Klaerschlammfaulung mehr als verdoppelt werden. Durch die thermophile Stufe zur Vorbehandlung der Bioabfaelle konnte die spezifische Biogasausbeute bei einer organischen Raumbelastung von 1,5 kg o TR/m{sup 3*}d gegenueber der 1-stufigen Co-Vergaerung leicht erhoeht werden. (orig.)

  17. Ozonation and thermal pre-treatment of municipal sewage sludge – Implications for toxicity and methane potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    The aim of this study was to determine the effects on the methane potential and the overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 °C). In general both treatments gave an increased methane potential. The thermal t...... treatment resulted in higher chemical oxygen demand (COD)-solubilisation, while the highest volatile fatty acids (VFA) increase was obtained with ozonation. The sludges had inhibiting effects in a barley seed germination assay and a yeast oestrogen screen both before and after pre...

  18. The multiple market-exposure of waste management companies: A case study of two Swedish municipally owned companies

    International Nuclear Information System (INIS)

    Corvellec, Hervé; Bramryd, Torleif

    2012-01-01

    Highlights: ► Swedish municipally owned waste management companies are active on political, material, technical, and commercial markets. ► These markets differ in kind and their demands follow different logics. ► These markets affect the public service, processing, and marketing of Swedish waste management. ► Articulating these markets is a strategic challenge for Swedish municipally owned waste management. - Abstract: This paper describes how the business model of two leading Swedish municipally owned solid waste management companies exposes them to four different but related markets: a political market in which their legitimacy as an organization is determined; a waste-as-material market that determines their access to waste as a process input; a technical market in which these companies choose what waste processing technique to use; and a commercial market in which they market their products. Each of these markets has a logic of its own. Managing these logics and articulating the interrelationships between these markets is a key strategic challenge for these companies.

  19. The multiple market-exposure of waste management companies: A case study of two Swedish municipally owned companies

    Energy Technology Data Exchange (ETDEWEB)

    Corvellec, Herve, E-mail: herve.corvellec@ism.lu.se [Department of Service Management, Lund University, Campus Helsingborg, PO Box 882, SE-251 08 Helsingborg (Sweden); Bramryd, Torleif [Department of Environmental Strategy, Lund University, Campus Helsingborg, PO Box 882, SE-251 08 Helsingborg (Sweden)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Swedish municipally owned waste management companies are active on political, material, technical, and commercial markets. Black-Right-Pointing-Pointer These markets differ in kind and their demands follow different logics. Black-Right-Pointing-Pointer These markets affect the public service, processing, and marketing of Swedish waste management. Black-Right-Pointing-Pointer Articulating these markets is a strategic challenge for Swedish municipally owned waste management. - Abstract: This paper describes how the business model of two leading Swedish municipally owned solid waste management companies exposes them to four different but related markets: a political market in which their legitimacy as an organization is determined; a waste-as-material market that determines their access to waste as a process input; a technical market in which these companies choose what waste processing technique to use; and a commercial market in which they market their products. Each of these markets has a logic of its own. Managing these logics and articulating the interrelationships between these markets is a key strategic challenge for these companies.

  20. Recovery of nitrogen and phosphorus from alkaline fermentation liquid of waste activated sludge and application of the fermentation liquid to promote biological municipal wastewater treatment.

    Science.gov (United States)

    Tong, Juan; Chen, Yinguang

    2009-07-01

    In previous publications we reported that by controlling the pH at 10.0 the accumulation of short-chain fatty acids (SCFA) during waste activated sludge (WAS) fermentation was remarkably improved [Yuan, H., Chen, Y., Zhang, H., Jiang, S., Zhou, Q., Gu, G., 2006. Improved bioproduction of short-chain fatty acids (SCFAs) from excess sludge under alkaline conditions. Environ. Sci. Technol. 40, 2025-2029], but significant ammonium nitrogen (NH(4)-N) and soluble ortho-phosphorus (SOP) were released [Chen, Y., Jiang, S., Yuan, H., Zhou, Q., Gu, G., 2007. Hydrolysis and acidification of waste activated sludge at different pHs. Water Res. 41, 683-689]. This paper investigated the simultaneous recovery of NH(4)-N and SOP from WAS alkaline fermentation liquid and the application of the fermentation liquid as an additional carbon source for municipal wastewater biological nitrogen and phosphorus removal. The central composite design (CCD) of the response surface methodology (RSM) was employed to optimize and model the simultaneous NH(4)-N and SOP recovery from WAS alkaline fermentation liquid. Under the optimum conditions, the predicted and experimental recovery efficiency was respectively 73.4 and 75.7% with NH(4)-N, and 82.0 and 83.2% with SOP, which suggested that the developed models described the experiments well. After NH(4)-N and SOP recovery, the alkaline fermentation liquid was added to municipal wastewater, and the influence of volume ratio of fermentation liquid to municipal wastewater (FL/MW) on biological nitrogen and phosphorus removal was investigated. The addition of fermentation liquid didn't significantly affect nitrification. Both SOP and total nitrogen (TN) removal were increased with fermentation liquid, but there was no significant increase at FL/MW greater than 1/35. Compared to the blank test, the removal efficiency of SOP and TN at FL/MW=1/35 was improved from 44.0 to 92.9%, and 63.3 to 83.2%, respectively. The enhancement of phosphorus and nitrogen

  1. Characterization of the pork market in nine municipalities in the department of Boyacá, Colombia

    Directory of Open Access Journals (Sweden)

    Diana Constanza Beltrán Hernández

    2014-05-01

    Full Text Available The pork market in the department of Boyacá is subject to fluctuations and instability, exposing it to the producer in unfavorable prices, ignorance of the quality of their product and low profitability. This research establishes the characteristics of the marketing pork systems in nine municipalities, to identify the aspects that contribute to improve the structure of formal marketing and to benefit the producer, sale points and final consumer. The potential for pork supply in volume and quality was determined, it was identified the marketing channels, we identified the motivators or inhibitors of pork purchase, his position in relation to the other meats, and the market potential, according to the existing marketing channels and it was established the requirements, in terms of presentation and pork price, in points of consumption. The statistical analysis was based on an analytical synthetic method, as it is based on the decomposition of the object of study, analyzing each and every one of the actors involved in the process. It was determined that the potential of pork production is relatively low. Both for producers, points of sale and local consumption, the main motivator of consumption is the palatability and the main inhibitor is the risk of transmission of the virus H1N1. It is concluded that the pork industry in Boyacá is in an evolutionary process that requires a continuing advice in production and marketing, and promotional consumption campaigns, in addition to the standardization of prices.

  2. Fate and impact of phthalates in activated sludge treated municipal wastewater on the water bodies in the Eastern Cape, South Africa.

    Science.gov (United States)

    Salaudeen, Taofeek; Okoh, Omobola; Agunbiade, Foluso; Okoh, Anthony

    2018-07-01

    The concentration and fates of six priority phthalate esters (PAEs); dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di (2-ethyl hexyl) phthalate (DEHP), and di-n-octyl phthalate (DOP) in wastewaters from the wastewater treatment plants (WWTPs) which adopted the activated sludge technology in the Amathole Municipality, Eastern Cape, South Africa were investigated. The six PAEs were detected in all the influents and in almost all the WWTP effluent of which DBP was the most abundant in the influent followed by DEHP. Influent concentration of DBP in the three WWTPs ranged between 2.7 and 2488 μgL -1 and the average effluent concentration was 4.90-8.88 μgL -1 . On average, the concentration of PAEs in WWTP effluents were higher than PAEs in the upstream and downstream of the discharging point suggesting PAE impact on the receiving water. The concentrations detected in the sludge of which DEHP and DBP were more pervasive ranged between 130 and 1094 μg/g dry weight. The average removal capacity; 27.3-99.5% suggested more adsorption on settling particles and sludge than biodegradation as high significant correlation was found between PAEs removal, total suspended solid and turbidity. Removal of high molecular weight and high octanol-water partition coefficient (logK ow ) PAEs through adsorption was found to be significantly high. It could be concluded that the release of PAEs into the sludge, and the amount in the final effluent which were found to exceed the acceptable levels allowed internationally, raises safety concern for both aquatic and human's health. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Sorption and release of organics by primary, anaerobic, and aerobic activated sludge mixed with raw municipal wastewater.

    Directory of Open Access Journals (Sweden)

    Oskar Modin

    Full Text Available New activated sludge processes that utilize sorption as a major mechanism for organics removal are being developed to maximize energy recovery from wastewater organics, or as enhanced primary treatment technologies. To model and optimize sorption-based activated sludge processes, further knowledge about sorption of organics onto sludge is needed. This study compared primary-, anaerobic-, and aerobic activated sludge as sorbents, determined sorption capacity and kinetics, and investigated some characteristics of the organics being sorbed. Batch sorption assays were carried out without aeration at a mixing velocity of 200 rpm. Only aerobic activated sludge showed net sorption of organics. Sorption of dissolved organics occurred by a near-instantaneous sorption event followed by a slower process that obeyed 1st order kinetics. Sorption of particulates also followed 1st order kinetics but there was no instantaneous sorption event; instead there was a release of particles upon mixing. The 5-min sorption capacity of activated sludge was 6.5±10.8 mg total organic carbon (TOC per g volatile suspend solids (VSS for particulate organics and 5.0±4.7 mgTOC/gVSS for dissolved organics. The observed instantaneous sorption appeared to be mainly due to organics larger than 20 kDa in size being sorbed, although molecules with a size of about 200 Da with strong UV absorbance at 215-230 nm were also rapidly removed.

  4. Evaluation and Source Apportionment of Heavy Metals (HMs) in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs) in Shanxi, China.

    Science.gov (United States)

    Duan, Baoling; Liu, Fenwu; Zhang, Wuping; Zheng, Haixia; Zhang, Qiang; Li, Xiaomei; Bu, Yushan

    2015-12-11

    Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index I(geo) and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. I(geo) classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes.

  5. Dialectics of public and market regulation of a region and municipality socio-economic development

    Directory of Open Access Journals (Sweden)

    Aleksandr Ivanovich Tatarkin

    2014-03-01

    Full Text Available Motives of improving public regulation influence to socio-economic and social processes, increasing quality and effectiveness of public (PR and market (MR regulators, their optimal and flexible cooperation were examined in the article. The essence and content of public-legal regulators (PLR in the sustainable and balanced development of territories, regions and country as a whole was reviewed. The PLR was classified by criteria of the “scale” of their regulation influence, regulation methods and consequences. Special attention was paid to the quality of PLR of federal and intergovernmental relations at the regional and municipal levels. Recommendations to improve the effectiveness of public and market regulators in regional and territorial development were suggested.

  6. European municipalities and the liberalized energy market; Les municipalites europeennes et le marche liberalise de l'energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    Municipalities are directly affected by the liberalization of the energy markets. Because they all consume or even produce energy, whether it be for their own consumption or to resell it, they often distribute gas, electricity or heat, they plan urban areas and organize the energy networks on their territory, while in addition citizens expect municipalities to inform them and even protect them against the possible excesses of energy salesmen. Elected representatives administrations, local agencies, municipal companies, citizens' associations etc., all have to innovate. This supplement to Energie-Cites INFO is intended to provide you with practical information and further analyses of the liberalization process. (authors)

  7. Municipal and Treasury Bond Market Segments Development at Bucharest Stock Exchange

    Directory of Open Access Journals (Sweden)

    Cornelia POP

    2012-02-01

    Full Text Available The current paper reviews the developments that took place, starting with November 2001, inside the Romanian Municipal and Treasury bond market segments at the Bucharest Stock Exchange. The development of a debt market has as a main objective to encourage the central, regional and local governments to consider bond finance as an important way for regional and local project investments; it could enhance the quality and the efficiency of financed projects and encourage long term financial planning. The relatively modest profile of the Romanian public bond sector at Bucharest Stock Exchange can be explained by the late introduction of the T-bonds (7 years after the bond sector was launched. Lacking the benchmark the T-bonds could offer, it was only natural for investors to avoid the (Municipal bond sector. The development of the domestic public bond sector is expected to continue in the years to come, mainly if through bond financing the central/regional and local authorities will support investment projects that will trigger and/or generate economic development.

  8. Reactor performance and microbial community dynamics during anaerobic co-digestion of municipal wastewater sludge with restaurant grease waste at steady state and overloading stages.

    Science.gov (United States)

    Razaviarani, Vahid; Buchanan, Ian D

    2014-11-01

    Linkage between reactor performance and microbial community dynamics was investigated during mesophilic anaerobic co-digestion of restaurant grease waste (GTW) with municipal wastewater sludge (MWS) using 10L completely mixed reactors and a 20day SRT. Test reactors received a mixture of GTW and MWS while control reactors received only MWS. Addition of GTW to the test reactors enhanced the biogas production and methane yield by up to 65% and 120%, respectively. Pyrosequencing revealed that Methanosaeta and Methanomicrobium were the dominant acetoclastic and hydrogenotrophic methanogen genera, respectively, during stable reactor operation. The number of Methanosarcina and Methanomicrobium sequences increased and that of Methanosaeta declined when the proportion of GTW in the feed was increased to cause an overload condition. Under this overload condition, the pH, alkalinity and methane production decreased and VFA concentrations increased dramatically. Candidatus cloacamonas, affiliated within phylum Spirochaetes, were the dominant bacterial genus at all reactor loadings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Microbial community adaptation influences long-chain fatty acid conversion during anaerobic codigestion of fats, oils, and grease with municipal sludge.

    Science.gov (United States)

    Ziels, Ryan M; Karlsson, Anna; Beck, David A C; Ejlertsson, Jörgen; Yekta, Sepehr Shakeri; Bjorn, Annika; Stensel, H David; Svensson, Bo H

    2016-10-15

    Codigesting fats, oils, and greases with municipal wastewater sludge can greatly improve biomethane recovery at wastewater treatment facilities. Process loading rates of fats, oils, and greases have been previously tested with little knowledge of the digester microbial community structure, and high transient fat loadings have led to long chain fatty acid (LCFA) accumulation and digester upsets. This study utilized recently-developed quantitative PCR assays for syntrophic LCFA-degrading bacteria along with 16S amplicon sequencing to relate changes in microbial community structure to LCFA accumulation during transient loading increases to an anaerobic codigester receiving waste restaurant oil and municipal wastewater sludge. The 16S rRNA gene concentration of the syntrophic β-oxidizing genus Syntrophomonas increased to ∼15% of the Bacteria community in the codigester, but stayed below 3% in the control digester that was fed only wastewater sludge. Methanosaeta and Methanospirillum were the dominant methanogenic genera enriched in the codigester, and together comprised over 80% of the Archaea community by the end of the experimental period. Constrained ordination showed that changes in the codigester Bacteria and Archaea community structures were related to measures of digester performance. Notably, the effluent LCFA concentration in the codigester was positively correlated to the specific loading rate of waste oil normalized to the Syntrophomonas 16S rRNA concentration. Specific loading rates of 0-1.5 × 10(-12) g VS oil/16S gene copies-day resulted in LCFA concentrations below 30 mg/g TS, whereas LCFA accumulated up to 104 mg/g TS at higher transient loading rates. Based on the community-dependent loading limitations found, enhanced biomethane production from high loadings of fats, oils and greases can be achieved by promoting a higher biomass of slow-growing syntrophic consortia, such as with longer digester solids retention times. This work also

  10. Critical evaluation of municipal solid waste composting and potential compost markets.

    Science.gov (United States)

    Farrell, M; Jones, D L

    2009-10-01

    Mechanical biological treatment (MBT) of mixed waste streams is becoming increasingly popular as a method for treating municipal solid waste (MSW). Whilst this process can separate many recyclates from mixed waste, the resultant organic residue can contain high levels of heavy metals and physical and biological contaminants. This review assesses the potential end uses and sustainable markets for this organic residue. Critical evaluation reveals that the best option for using this organic resource is in land remediation and restoration schemes. For example, application of MSW-derived composts at acidic heavy metal contaminated sites has ameliorated soil pollution with minimal risk. We conclude that although MSW-derived composts are of low value, they still represent a valuable resource particularly for use in post-industrial environments. A holistic view should be taken when regulating the use of such composts, taking into account the specific situation of application and the environmental pitfalls of alternative disposal routes.

  11. Feasibility study of green wastes composting with digested and dewatering sludge from municipal wastewater treatment plant in Iran

    Directory of Open Access Journals (Sweden)

    Neamat Jaafarzadeh Haghighi Fard

    2015-09-01

    Full Text Available Background: Composting as a waste management technology is becoming more widespread. The purpose of this study was to assess the feasibility and to find the most effective composting process for the ratio of green waste, digested and dewatered sludge from Chonibieh wastewater treatment plant in the west region of Ahvaz. Methods: The composting time was 23 days and the evaluated parameters in this period of the study were organic carbon, total nitrogen, phosphorus, carbon to nitrogen ratio (C/N, moisture content and pH. The C/N ratio was maintained at 30 with weight:weight ratio of 1:1, 1:2, 1:3 (digested and dewatered sludge to green waste. Results: It was observed that vessel R3 produced higher quality of compost with final total nitrogen (1.28%, final total phosphorus (0.71%, final total organic carbon (TOC (25.78% and C/N (20.65% within the 23 days of composting. While vessel R1 produced higher final total nitrogen and total phosphorus with lower amount of total coliform indicating suitable quality of composting. Therefore, the results showed that the characteristics of dewatered sludge mixed with green waste proportion of green waste significantly influenced the compost quality and process dynamics. The results also showed that the quality of final products in all the conditions was in agreement with Global Organic Textile Standard (GOTS and World Health Organization (WHO guidelines. However, the moisture content ratios were lower than the mentioned guidelines. With regards to microbial quality, all three ratios were in agreement with US Environmental Protection Agency (EPA and Iranian guidelines. Conclusion: It is suggested that the final product of composting can be safely used in farmland and green space.

  12. Co-composting of municipal solid waste mixed with matured sewage sludge: The relationship between N2O emissions and denitrifying gene abundance.

    Science.gov (United States)

    Bian, Rongxing; Sun, Yingjie; Li, Weihua; Ma, Qiang; Chai, Xiaoli

    2017-12-01

    Aerobic composting is an alternative measure to the disposal of municipal solid waste (MSW). However, it produces nitrous oxide (N 2 O), a highly potent greenhouse via microbial nitrification and denitrification. In this study, the effects of matured sewage sludge (MSS) amendment on N 2 O emissions and the inter-relationships between N 2 O emissions and the abundance of denitrifying bacteria were investigated during aerobic composting of MSW. The results demonstrated that MSW composting with MSS amendments (C1, and C2, with a MSW to MSS ratio of 2:1 and 4:1, (v/v), respectively) significantly increased N 2 O emissions during the initial stage, yet contributed to the mitigation of N 2 O emissions during the cooling and maturation stage. MSS amended composting emitted a total of 18.4%-25.7% less N 2 O than the control treatment without MSS amendment (CK). Matured sewage sludge amendment also significantly altered the abundance of denitrifying bacteria. The quantification of denitrifying functional genes revealed that the N 2 O emission rate had a significant positive correlation with the abundance of the nirS, nirK genes in both treatments with MSS amendment. The nosZ/(nirS + nirK) ratio could be a good indicator for predicting N 2 O emissions. The higher N 2 O emission rate during the initial stage of composting mixed with MSS was characterized by lower nosZ/(nirS + nirK) ratios, compared to CK treatment. Higher ratios of nosZ/(nirS + nirK) were measured during the cooling and maturation stage in treatments with MSS which resulted in a reduction of the N 2 O emissions. These results demonstrated that MSS amendment could be a valid strategy for mitigating N 2 O emissions during MSW composting. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Pilot-scale anaerobic co-digestion of municipal biomass waste and waste activated sludge in China: Effect of organic loading rate

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xiao, E-mail: liuxiao07@mails.tsinghua.edu.cn [School of Environment, Tsinghua University, Beijing 100084 (China); Wang Wei; Shi Yunchun; Zheng Lei [School of Environment, Tsinghua University, Beijing 100084 (China); Gao Xingbao [Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Qiao Wei [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Zhou Yingjun [Department of Urban and Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540 (Japan)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) was examined on a pilot-scale reactor. Black-Right-Pointing-Pointer System performance and stability under OLR of 1.2, 2.4, 3.6, 4.8, 6.0 and 8.0 kg VS (m{sup 3} d){sup -1} were analyzed. Black-Right-Pointing-Pointer A maximum methane production rate of 2.94 m{sup 3} (m{sup 3} d){sup -1} was achieved at OLR of 8.0 kg VS (m{sup 3} d){sup -1} and HRT of 15d. Black-Right-Pointing-Pointer With the increasing OLRs, pH values, VS removal rate and methane concentration decreased and VFA increased. Black-Right-Pointing-Pointer The changing of biogas production rate can be a practical approach to monitor and control anaerobic digestion system. - Abstract: The effects of organic loading rate on the performance and stability of anaerobic co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) were investigated on a pilot-scale reactor. The results showed that stable operation was achieved with organic loading rates (OLR) of 1.2-8.0 kg volatile solid (VS) (m{sup 3} d){sup -1}, with VS reduction rates of 61.7-69.9%, and volumetric biogas production of 0.89-5.28 m{sup 3} (m{sup 3} d){sup -1}. A maximum methane production rate of 2.94 m{sup 3} (m{sup 3} d){sup -1} was achieved at OLR of 8.0 kg VS (m{sup 3} d){sup -1} and hydraulic retention time of 15 days. With increasing OLRs, the anaerobic reactor showed a decrease in VS removal rate, average pH value and methane concentration, and a increase of volatile fatty acid concentration. By monitoring the biogas production rate (BPR), the anaerobic digestion system has a higher acidification risk under an OLR of 8.0 kg VS (m{sup 3} d){sup -1}. This result remarks the possibility of relating bioreactor performance with BPR in order to better understand and monitor anaerobic digestion process.

  14. Pilot-scale anaerobic co-digestion of municipal biomass waste and waste activated sludge in China: Effect of organic loading rate

    International Nuclear Information System (INIS)

    Liu Xiao; Wang Wei; Shi Yunchun; Zheng Lei; Gao Xingbao; Qiao Wei; Zhou Yingjun

    2012-01-01

    Highlights: ► Co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) was examined on a pilot-scale reactor. ► System performance and stability under OLR of 1.2, 2.4, 3.6, 4.8, 6.0 and 8.0 kg VS (m 3 d) −1 were analyzed. ► A maximum methane production rate of 2.94 m 3 (m 3 d) −1 was achieved at OLR of 8.0 kg VS (m 3 d) −1 and HRT of 15d. ► With the increasing OLRs, pH values, VS removal rate and methane concentration decreased and VFA increased. ► The changing of biogas production rate can be a practical approach to monitor and control anaerobic digestion system. - Abstract: The effects of organic loading rate on the performance and stability of anaerobic co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) were investigated on a pilot-scale reactor. The results showed that stable operation was achieved with organic loading rates (OLR) of 1.2–8.0 kg volatile solid (VS) (m 3 d) −1 , with VS reduction rates of 61.7–69.9%, and volumetric biogas production of 0.89–5.28 m 3 (m 3 d) −1 . A maximum methane production rate of 2.94 m 3 (m 3 d) −1 was achieved at OLR of 8.0 kg VS (m 3 d) −1 and hydraulic retention time of 15 days. With increasing OLRs, the anaerobic reactor showed a decrease in VS removal rate, average pH value and methane concentration, and a increase of volatile fatty acid concentration. By monitoring the biogas production rate (BPR), the anaerobic digestion system has a higher acidification risk under an OLR of 8.0 kg VS (m 3 d) −1 . This result remarks the possibility of relating bioreactor performance with BPR in order to better understand and monitor anaerobic digestion process.

  15. Removal of the Inert Organic Fraction of Municipal Wastewater Using the Integrated Activated Sludge/Trickling Filter System

    Directory of Open Access Journals (Sweden)

    mehraban sadeghi

    2015-01-01

    Full Text Available The discharge of phenol and chlorinated compounds, fatty acids, tannin, lignin, and their by-products into receptive waters poses serious hazards for the aquatic life. In this study, the efficiency of a tow-step process of activated sludge-trickling filter (AS/TF in the removal of inert chemical materials that defy conventional treatment processes was investigated. For this purpose, an integrated activated sludge process (industrial scale was used sequentially with a trickling filter (pilot scale. Inside a tank with an effective volume of 6.87 m3 was installed 5.78 m3 of polypropylene 2HX media with a specific area of 240 m2/m3. The hydraulic loading rate (HLR of the trickling filter during the startup period (90 days was 3.6 m3/h which was raised to 3.6-6 m3/h in the operation period (120 days, with the best effluent quality achieved at HLR=5.4 m3/h. For the purposes of the experiments in this study, four reactors, each 1256 cm3 in volume, were fed the WWTP effluent and concurrently a glucose substrate containing a COD content equal to that fed to the four reactors was fed into two identical reactors; all the reactors were subsequently run for 480 h in aerobic conditions. Nutrients, pH, and DO (as environmental control indicators as well as soluble and total COD were measured twice daily. The effluent values of soluble inert materials (SI, total soluble COD (STO, degradable suspended materials (XSO, degradable COD (CSO, refractory suspended materials (XI, and degradable soluble materials (SSO for AS were calculated as 40, 227, 94, 281, 251, and 187, respectively, while the same parameters for the AS/TF were 20, 227, 104, 311, 241, and 207 mg/l, respectively. The results showed that the activated sludge process when combined with the trickling filter has a twofold capability, compared to when used alone, in removing inert COD. It was also shown that treatment levels in conventional WWTPs can be improved by integrating conventional treatment

  16. Municipalities and opening up of energy markets; Les municipalites et l'ouverture des marches energetiques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The opening of energy markets in Europe is modifying deeply the general framework of economic activity, modes of organisation and ways of thinking. The energy future in Europe is being determined under the influence of Community directives relating to electricity and to gas. It is also being moulded by national legislation, which is being progressively put into place in different countries of the European Union and in other European countries such as those of central Europe. These will affect the conditions under which policies for energy efficiency, for the development of renewable energy and for combating climate change are to be implemented. The liberalization of energy markets is a new and highly significant element in the European energy scene and municipalities are making a constructive contribution to this process. About 160 representatives of municipalities from 19 different European countries met at the Energie-Cites Seminar in Barcelona in order to become better informed, to exchange opinions and to debate the consequences at their level of the opening of energy markets. As a consequence they have asked themselves questions and exchanged ideas in relation with their respective situations regarding energy planning, production, distribution, and the role of population motivative. The seminar is organized around one round table about the threats and the opportunities of the opening up of energy markets, and three sessions about: what is going to change for the municipality as energy consumer, what is going to change for the municipality as energy producer, distributor and regulator-developer, and what is going to change for the municipality as motivative. (J.S.)

  17. Influence of potassium hydroxide activation on characteristics and environmental risk of heavy metals in chars derived from municipal sewage sludge.

    Science.gov (United States)

    Li, Zhengjia; Deng, Hui; Yang, Le; Zhang, Genlin; Li, Yuqi; Ren, Yansen

    2018-05-01

    To investigate the influence of KOH activation on characteristics and environmental risk of heavy metals in chars, sludge was pyrolyzed with varying amount of KOH. The analyzation of characteristics and potential ecological risk evaluation of heavy metals were conducted by surface area analyzer, FTIR, XRD and BCR sequential extraction. The activated chars have higher surface area and lower content of silica compared to those without being activated. The activation of KOH promoted residual fraction of Cd, meanwhile, Zinc, Cr, Ni and Mn were converted to relatively unstable fractions (F2 and F3). The results of risk assessment indicated that the potential ecological risk level of Cd was reduced in activated chars, while risk level of Zn, Cr, Ni and Mn were increased after pyrolysis with KOH activation. The potential ecological risk of heavy metals in activated chars was further declined, and the risk level transformed from moderate to low. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge.

    Science.gov (United States)

    Åmand, Lars-Erik; Kassman, Håkan

    2013-08-01

    Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW(th) circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. A novel approach of anaerobic co-digestion between organic fraction of food waste and waste sludge from municipal wastewater treatment plant: Effect of mixing ratio

    Science.gov (United States)

    Nga, Dinh Thi; Ngoc, Tran Thi Minh; Van Ty, Nguyen; Thuan, Van Tan

    2017-09-01

    The aim of this study was to investigate the effect of mixing ratio of co-anaerobic digestion between dewatered waste sludge from municipal wastewater treatment plant (DS) and organic fraction of food waste (FW). The experiment was carried out in 3L reactors for 16 days at ambient temperature. Four mixing ratios of DW and FW was investigated including 100 % DS : 0 % FW (Run S100); 75% DS : 25 % FW (Run S75); 50% DS : 50% FW (Run S50); and 25% DS : 75% FW (Run S25) in term of VS concentration. As a result, the Run S50 achieved best performance among the four funs indicated in biogas accumulation of 32.48 L biogas and methane yield of 358.9 400ml CH4/g VS removal after 16 days operation at ambient temperature. Biogas accumulation of Run S25 was higher than that of Run S75. Run S100 produced the lowest of biogas of all runs. It is concluded that co-anaerobic digestion of different organic sources could enhance the performance of methane fermentation.

  20. Mesophilic anaerobic co-digestion of the organic fraction of municipal solid waste with the liquid fraction from hydrothermal carbonization of sewage sludge.

    Science.gov (United States)

    De la Rubia, M A; Villamil, J A; Rodriguez, J J; Borja, R; Mohedano, A F

    2018-06-01

    In the present study, the influence of substrate pre-treatment (grinding and sieving) on batch anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) was first assessed, then followed by co-digestion experiments with the liquid fraction from hydrothermal carbonization (LFHTC) of dewatered sewage sludge (DSS). The methane yield of batch anaerobic digestion after grinding and sieving (20 mm diameter) the OFMSW was considerably higher (453 mL CH 4 STP g -1 VS added ) than that of untreated OFMSW (285 mL CH 4 STP g -1 VS added ). The modified Gompertz model adequately predicted process performance. The maximum methane production rate, R m , for ground and sieved OFMSW was 2.4 times higher than that of untreated OFMSW. The anaerobic co-digestion of different mixtures of OFMSW and LFHTC of DSS did not increase the methane yield above that of the anaerobic digestion of OFMSW alone, and no synergistic effects were observed. However, the co-digestion of both wastes at a ratio of 75% OFMSW-25% LFHTC provides a practical waste management option. The experimental results were adequately fitted to a first-order kinetic model showing a kinetic constant virtually independent of the percentage of LFHTC (0.52-0.56 d -1 ) and decreasing slightly for 100% LFHTC (0.44 d -1 ). Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Predicting the co-melting temperatures of municipal solid waste incinerator fly ash and sewage sludge ash using grey model and neural network.

    Science.gov (United States)

    Pai, Tzu-Yi; Lin, Kae-Long; Shie, Je-Lung; Chang, Tien-Chin; Chen, Bor-Yann

    2011-03-01

    A grey model (GM) and an artificial neural network (ANN) were employed to predict co-melting temperature of municipal solid waste incinerator (MSWI) fly ash and sewage sludge ash (SSA) during formation of modified slag. The results indicated that in the aspect of model prediction, the mean absolute percentage error (MAPEs) were between 1.69 and 13.20% when adopting seven different GM (1, N) models. The MAPE were 1.59 and 1.31% when GM (1, 1) and rolling grey model (RGM (1, 1)) were adopted. The MAPEs fell within the range of 0.04 and 0.50% using different types of ANN. In GMs, the MAPE of 1.31% was found to be the lowest when using RGM (1, 1) to predict co-melting temperature. This value was higher than those of ANN2-1 to ANN8-1 by 1.27, 1.25, 1.24, 1.18, 1.16, 1.14 and 0.81%, respectively. GM only required a small amount of data (at least four data). Therefore, GM could be applied successfully in predicting the co-melting temperature of MSWI fly ash and SSA when no sufficient information is available. It also indicates that both the composition of MSWI fly ash and SSA could be applied on the prediction of co-melting temperature.

  2. Comprehensive monitoring and management of a long-term thermophilic CSTR treating coffee grounds, coffee liquid, milk waste, and municipal sludge.

    Science.gov (United States)

    Shofie, Mohammad; Qiao, Wei; Li, Qian; Takayanagi, Kazuyuki; Li, Yu-You

    2015-09-01

    The CSTR process has previously not been successfully applied to treat coffee residues under thermophilic temperature and long term operation. In this experiment, the CSTR was fed with mixture substrate (TS ∼ 70 g/L) of coffee grounds, coffee wastewater, milk waste and municipal sludge and it was operated under 55 °C for 225 days. A steady state was achieved under HRT 30 days and OLR 4.0 kg-COD/m(3)/d. However, there was an 35 days inhibition with VFA accumulation (propionic acid 700-1900 mg/L) when doubling the OLR by shortening HRT to 15 days. But, an addition of microelements and sulfate (0.5 g/L) in feedstock increased reactor resilience and stability under high loading rate and propionic acid stress. Continuous monitoring of hydrogen in biogas indicated the imbalance of acetogenesis. The effectiveness of comprehensive parameters (total VFA, propionic acid, IA/PA, IA/TA and CH4 content) was proved to manage the thermophilic system. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Research and development on municipal Wastewater treatment processes using electron beams

    International Nuclear Information System (INIS)

    Kashiwaya, Mamoru

    1994-01-01

    This paper was described concerning the experimental results and their engineering evaluations on electron beam irradiation treatment to effluent and sludge produced in existing municipal wastewater treatment plants implemented by the Japan Atomic Energy Research Institute and the study committee for past five years. Laboratory tests using an electron accelerator were carried out for the purposes of disinfection both to effluent and to dewatered sludge. And composting tests by a pilot-plant were also carried out to find the optimal conditions on design and operation, and initial and operational cost estimations for pelletized sludge with/without the irradiation. It was found that these applications to effluent, sludge and supernatant were quite effective. However, several problems awaiting solution were found from the tests and evaluating works on the matters of marketed electron accelerators. As the results of tests and evaluating works, electron beam irradiation treatment process applied to effluent should be carried out at the municipal wastewater treatment plants. Regenerated granular activated carbon treated by electron beam irradiation may also be applicable to remove hazardous organic substances in effluent. However, long-term tests by pilotplants will be necessary to determine the design criteria, operation and maintenance conditions, and so on. For composting of dewatered sludge produced at municipal wastewater treatment plants, several sizes of smaller electron accelerator are required to be on the market. Especially, medium and small sizes municipalities expect to install composting facilities in the plant. (J.P.N.)

  4. Electricity Recovery from Municipal Sewage Wastewater Using a Hydrogel Complex Composed of Microbially Reduced Graphene Oxide and Sludge

    Directory of Open Access Journals (Sweden)

    Naoko Yoshida

    2016-08-01

    Full Text Available Graphene oxide (GO has recently been shown to be an excellent anode substrate for exoelectrogens. This study demonstrates the applicability of GO in recovering electricity from sewage wastewater. Anaerobic incubation of sludge with GO formed a hydrogel complex that embeds microbial cells via π-π stacking of microbially reduced GO. The rGO complex was electrically conductive (23 mS·cm−1 and immediately produced electricity in sewage wastewater under polarization at +200 mV vs. Ag/AgCl. Higher and more stable production of electricity was observed with rGO complexes (179–310 μA·cm−3 than with graphite felt (GF; 79–95 μA·cm−3. Electrochemical analyses revealed that this finding was attributable to the greater capacitance and smaller internal resistance of the rGO complex. Microbial community analysis showed abundances of Geobacter species in both rGO and GF complexes, whereas more diverse candidate exoelectrogens in the Desulfarculaceae family and Geothrix genus were particularly prominent in the rGO complex.

  5. Performance evaluation of the sulfur-redox-reaction-activated up-flow anaerobic sludge blanket and down-flow hanging sponge anaerobic/anoxic sequencing batch reactor system for municipal sewage treatment.

    Science.gov (United States)

    Hatamoto, Masashi; Ohtsuki, Kota; Maharjan, Namita; Ono, Shinya; Dehama, Kazuya; Sakamoto, Kenichi; Takahashi, Masanobu; Yamaguchi, Takashi

    2016-03-01

    A sulfur-redox-reaction-activated up-flow anaerobic sludge blanket (UASB) and down-flow hanging sponge (DHS) system, combined with an anaerobic/anoxic sequencing batch reactor (A2SBR), has been used for municipal sewage treatment for over 2 years. The present system achieved a removal rate of 95±14% for BOD, 74±22% for total nitrogen, and 78±25% for total phosphorus, including low water temperature conditions. Sludge conversion rates during the operational period were 0.016 and 0.218 g-VSS g-COD-removed(-1) for the UASB, and DHS, respectively, which are similar to a conventional UASB-DHS system, which is not used of sulfur-redox-reaction, for sewage treatment. Using the sulfur-redox reaction made advanced treatment of municipal wastewater with minimal sludge generation possible, even in winter. Furthermore, the occurrence of a unique phenomenon, known as the anaerobic sulfur oxidation reaction, was confirmed in the UASB reactor under the winter season. Copyright © 2016. Published by Elsevier Ltd.

  6. Initiative for local district heating. New chances for municipal utilities. Boundary conditions for the heat market; Initiative Nahwaerme. Neue Chancen fuer Stadtwerke. Rahmenbedingungen fuer den Waermemarkt

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, Michael [K.Group GmbH, Muenchen (Germany). Bereich Nachhaltige Energieversorgung und Stadtentwicklung

    2009-06-15

    In the regulated market, municipal utilities are forced to find new fields of activity. The heat market offers good chances. For example, local district heating grids can be established, independent power generation can be encouraged, and new services can be offered which may increase customer loyalty. The district heating initiative of the Baden-Wuerttemberg Minister of the Environment was launched early in 2009 with the intention to offer valuable assistance to the municipal utilities. (orig.)

  7. The hierarchical porous structure bio-char assessments produced by co-pyrolysis of municipal sewage sludge and hazelnut shell and Cu(II) adsorption kinetics.

    Science.gov (United States)

    Zhao, Bing; Xu, Xinyang; Zeng, Fanqiang; Li, Haibo; Chen, Xi

    2018-05-04

    The co-pyrolysis technology was applied to municipal sewage sludge (MSS) and hazelnut shell with alkaline activating agent K 2 CO 3 under N 2 atmosphere. The innovative bio-char produced by co-pyrolysis had significant physical and chemical characteristics. The specific surface area reached 1990.23 m 2 /g, and the iodine absorption number was 1068.22 mg/g after co-pyrolysis at 850 °C. Although hazelnut shell was a kind of solid waste, it also had abundant cellulose resource, which could contribute to porous structure of bio-char during co-pyrolysis with MSS and decrease total heavy metals contents of raw material to increase security of bio-chars. Meanwhile, the residual fractions of heavy metals in bio-char were above 92.95% after co-pyrolysis at 900 °C except Cd to prevent heavy metals digestion, and the bio-char presented significant immobilization behavior from co-pyrolysis technology. Moreover, the yield and the iodine absorption number of bio-chars under different process variables were analyzed, and it was confirmed that appropriate process variables could contribute the yield and the iodine absorption number of bio-char and prevent to etch pore structure excessively to collapse. The changes of surface functional groups and crystallographic structure before and after co-pyrolysis were analyzed by FTIR and XRD, respectively. The hierarchical porous structure of bio-char was presented by SEM and N 2 adsorption-desorption isotherm. The Cu(II) adsorption capacity of the bio-char was 42.28 mg/g after 24 h, and surface functional groups acted as active binding sites for Cu(II) adsorption. Langmuir model and pseudo-second-order model can describe process of Cu(II) adsorption well.

  8. Environmental application of gamma technology: Update on the Canadian sludge irradiator

    Science.gov (United States)

    Swinwood, Jean F.; Fraser, Frank M.

    1993-10-01

    Waste treatment and disposal technologies have recently been subjected to increasing public and regulatory scrutiny. Concern for the environment and a heightened awareness of potential health hazards that could result from insufficient or inappropriate waste handling methods have combined to push waste generators in their search for new treatment alternatives. Gamma technology can offer a new option for the treatment of potentially infectious wastes, including municipal sewage sludge. Sewage sludge contains beneficial plant nutrients and a high organic component that make it ideal as a soil conditioning agent or fertilizer bulking material. It also carries potentially infectious microorganisms which limit opportunities for beneficial recycling of sludges. Gamma irradiation-disinfection of these sludges offers a reliable, fast and efficient method for safe sludge recycling. Nordion International's Market Development Division was created in 1987 as part of a broad corporate reorganization. It was given an exclusive mandate to develop new applications of gamma irradiation technology and markets for these new applications. Nordion has since explored and developed opportunities in food irradiation, pharmaceutical/cosmetic products irradiation, biomedical waste sterilization, airline waste disinfection, and sludge disinfection for recycling. This paper focuses on the last of these -a proposed sludge recycling facility that incorporates a cobalt 60 sludge irradiator.

  9. Physical characterization and sanitary conditions of cheese type cabacinha market places in three municipalities of the Jequitinhonha Valley, MG, Brazil

    Directory of Open Access Journals (Sweden)

    Adair da Silva Santos Filho

    2017-09-01

    Full Text Available Cheese type cabacinha from Vale do Jequitinhonha is obtained by curd heating in a similar process made to Mozzarella, but the raw milk is unpasteurized and the final product is stored unpackaged and at room temperature. This milk derivative may contribute to the increase the income of the local population, especially the residents of the edges of roads, due to the flow of vehicles and possible buyers. The purpose of this work was to identify the physical and sanitary conditions of cheese type cabacinha market places present in three municipalities of the Vale do Jequitinhonha, MG, Brazil. Previously the investigation was detected the number of marketplaces that sell these cheese in the Medina, Cachoeira de Pajeú and Pedra Azul, municipalities of the state of Minas Gerais, Brazil, located on the surrounding area of the highways BR 251 and BR 116. Afterward as developed a physical and sanitary checklist and it were filled in loco. It was observed that most market places were not provided of masonry walls, piped water or toilet and sink. It is also common to the presence of possible contamination vectors in surroundings, such as dogs and insects. It is verified that most of these cheese is exposed in pairs held by string and unpackaged. This study demonstrated the precariousness of the physical structures and consequently the lack of adequate sanitary conditions in the cheese type cabacinha market places. Because it is an artisanal product from family farming, which generates income and employment in the field deserve more attention of competent state and municipal authorities.

  10. The EDP data base as a marketing instrument in the supply industry. Methods and experiences in natural gas customer acquisition of the Munich municipal utilities

    International Nuclear Information System (INIS)

    Wind, F.; Disser, U.

    1994-01-01

    The natural gas marketing concept of the Munich municipal utilities describes the aims and objectives for the acquisition of new customers beyond the year 2000. One target is to extend the grids into new areas but also activate natural gas clients in densely populated areas. The marketing strategies concentrate on extensive advice and consulting co-ordinated by the customer service representatives with the support of electronic data processing. The following report shows how modern database systems were integrated into marketing activities by the Munich municipal utility company and describes the strategies selected in new areas and areas with a high customer population. (orig.) [de

  11. An investigation of co-combustion municipal sewage sludge with biomass in a 20kW BFB combustor under air-fired and oxygen-enriched condition.

    Science.gov (United States)

    Kumar, Rajesh; Singh, Ravi Inder

    2017-12-01

    The behavior of municipal sewage sludge (MSS) with biomass (Guar stalks (GS), Mustard Husk (MH), Prosopis Juliflora Wood (PJW)) has been investigated in a 20kW bubbling fluidized bed (BFB) combustor under both air-fired (A-F) and oxygen-enriched (O-E) conditions. The work presented is divided into three parts, first part cover the thermogravimetric analysis (TGA), second part cover the experimental investigation of BFB combustor, and third part covers the ash analysis. TGA was performed with a ratio of 50%MSS/50%biomass (GS, MH, PJW) and results show that 50%MSS/50%GS has highest combustion characteristic factor (CCF). The experimental investigation of BFB combustor was performed for two different ratios of MSS/biomass (50%/50% and 25%/75%) and the combustion characteristics of blends were distinctive under both A-F and O-E condition. Despite 50%MSS/50%GS showing the highest combustion performance in TGA analysis, it formed agglomerates during burning in BFB. Due to this formation of large amount of agglomerates, de-fluidization was observed in the combustor bed after 65-75min in A-F conditions. The rate of de-fluidization increased under O-E condition. The de-fluidization problem disappeared when the share of MSS was reduced to 25%, but small amounts of the agglomerate were still present in the bed. With oxygen enhancement, the combustion efficiency of BFB combustor was improved and flue gasses were found within permissible limit. The maximum conceivable combustion efficiency (97.1%) for BFB combustor was accomplished by using 50% MSS/50%PJW under O-E condition. Results show that a ratio of 25%MSS/75%biomass combusted successfully inside the BFB combustor and extensive work is required for efficient utilization of significant share of MSS with biomass. SEM/EDS analyses were performed for agglomerate produced and for the damaged heater to study the surface morphology and compositions. The elemental heterogeneity of fly ash generated during MSS/biomass combustion

  12. Ethnobotanical survey of medicinal plants marketed in the municipality of Uruará, Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Reinaldo Lucas Cajaiba

    2016-02-01

    Full Text Available The present study aimed to perform an ethnobotanical survey of medicinal plants marketed by the population of the municipality of Uruará, Pará, and its main districts. The respondents mentioned 63 species distributed in 36 botanical families. The most representative families were Lamiaceae, Asteraceae, Fabaceae and Rutaceae. The species with the highest Use Value were capim cidreira (Cymbopogon citratus, UV = 0.90, mastruz (Chenopodium ambrosioides, UV = 0.83 and hortelã (Mentha sp., UV = 0.79, while capim cidreira (Cymbopogon citratus and picão (Bidens pilosa had a higher indicator value, and were indicated as a tranquilizer/painkiller and for treating kidney disease, respectively. Among the main disorders treated with medicinal plants, diseases of the digestive system, infections/inflammations, colds and respiratory system diseases were the most cited. There was no significant difference between the number of species mentioned and the number of individuals per family or the distance of households to the urban zone. There was also no difference between the number of species mentioned and education level. Most medicinal plants marketed in the municipality are herbs, leaves are the most used parts and the most common form of preparation is tea.

  13. Ethnobotanical survey of medicinal plants marketed in the municipality of Uruará, Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Reinaldo Lucas Cajaiba

    2016-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2016v29n1p115 The present study aimed to perform an ethnobotanical survey of medicinal plants marketed by the population of the municipality of Uruará, Pará, and its main districts. The respondents mentioned 63 species distributed in 36 botanical families. The most representative families were Lamiaceae, Asteraceae, Fabaceae and Rutaceae. The species with the highest Use Value were capim cidreira (Cymbopogon citratus, UV = 0.90, mastruz (Chenopodium ambrosioides, UV = 0.83 and hortelã (Mentha sp., UV = 0.79, while capim cidreira (Cymbopogon citratus and picão (Bidens pilosa had a higher indicator value, and were indicated as a tranquilizer/painkiller and for treating kidney disease, respectively. Among the main disorders treated with medicinal plants, diseases of the digestive system, infections/inflammations, colds and respiratory system diseases were the most cited. There was no significant difference between the number of species mentioned and the number of individuals per family or the distance of households to the urban zone. There was also no difference between the number of species mentioned and education level. Most medicinal plants marketed in the municipality are herbs, leaves are the most used parts and the most common form of preparation is tea.

  14. Codigestion at municipal WWTP'S. Experiences and energy sufficiency of a sludge treatment process; Codigestion en EDARs urbanas. Experiencias y suficiencia energetica del proceso de tratamiento de lodos

    Energy Technology Data Exchange (ETDEWEB)

    Aguilo Martos, P.; Freixo Rey, A.; Estany Barrera, R.

    2012-07-01

    Anaerobic digestion is one of the most widely used technologies for the stabilisation and reduction of the sludge generated in a Waste Water Treatment Plant (WWTP). This technology allows the sludge to be treated within the current regulations, reducing the sludge volume and producing the use full biogas which can be used for power generation at a cogeneration plant, resulting in a reduction in the operating costs of the installation. The following article presents a complement to optimize the operation of anaerobic digestion installations: the anaerobic codigestion. Anaerobic digestion facilities are adequate for the combined treatment, in the same digestion units, of sludge, agricultural products or sub products, food wastes, and even industrial wastes (with strict limitations on wastes containing toxic contaminants), thereby increasing, notably, the biogas production. In some cases the biogas generated, with adequate treatment, can satisfy the total electricity demand of a WWTP and even produce an excess, thus allowing the export of the surplus energy to the electricity distribution network, according to different economic retribution models. Likewise, this document describes the different stages necessary to implement the anaerobic codigestion process in a WWTP, from the systematic search for products in the waste or sub product market through the sizing and legalization of the reception facility, the dosing of the product to the digester, commissioning and its incorporation into the routine operation of the WWTP. The article present the results obtained from the incorporation of an anaerobic co digestion process in the Sant Feliu de Llobregat WWTP situated in the Barcelona province. (Author)

  15. Usage of Social Media in City Marketing: A Research on 30 Metropolitan Municipalities in Turkey

    OpenAIRE

    Niyazi Gümüş

    2017-01-01

    Rapid changes in information and communication technologies cause serious developments in marketing field similar to every sector. In parallel with these developments, the social media channels which appear as Web 2.0 applications have a number of advantages in comparison with traditional media channels. Social media gained a place in marketing activities because of its advantages. Social media is added on instruments in line with these developments that countries benefit in marketing activit...

  16. Marketing Of Local Spices In Owerri Municipal Of Imo State, Nigeria ...

    African Journals Online (AJOL)

    The type of data collected included socio-economic characteristic of the spices traders, purchase and sales transactions, marketing cost and marketing margins, regression analysis was used to analyze the influence of socio-economic variable on the traders income descriptive statistics such as means, percentages and ...

  17. Overview of municipal sludge fluid bed incineration in North America--from green to greener--the Lakeview, the Duffin Creek and the Southerly experiences.

    Science.gov (United States)

    Dangtran, K; Takmaz, L; Pham, H; Bergel, J Y; Welp, J; Burrowes, P

    2011-01-01

    Thermal processes used in sludge disposal have become more attractive as process improvements have been introduced, such as power generation and efficient heat recovery. More and more utilities and agencies are reevaluating their sludge management practices to ensure that they are providing sustainable management solutions for their clients. The thermal process design approach to the disposal of sludge is not only designed to achieve stricter emission limits but also is more energy efficient compared to its predecessors. Increasing numbers of new plants are being built every year with more energy efficient heat recovery features such as air preheating and cogeneration with steam and electricity production. This paper presents an overview of fluid bed incineration in North America and its evolution over the last decades. Case studies of the last three newest and largest plants in North America are presented, including the Lakeview Plant, Duffin Creek Plant, both in Ontario, Canada and the Southerly Plant in Cleveland, Ohio, USA.

  18. The expanded role of municipal utilities in a deregulated power market

    Energy Technology Data Exchange (ETDEWEB)

    Prudhomme, H. [Sudbury Hydro Electric Commission, Sudbury, ON (Canada)

    1998-09-01

    A review of how Sudbury Hydro Electric Commission is meeting the challenges of transforming itself from a regulated monopoly into a competitive business was presented. The utility designed its organization in a Business Unit Model and has developed alliances and partnerships with the City of Sudbury, other municipalities, other utilities and the private sector. The internal `business units` include wires, metering, billing, energy services, district energy, telecommunications and radio services. The physical network includes (1) SCADA (Supervisory Control And Acquisition) devices at all substations and many switch locations, (2) automated meter reading devices for electric, water and gas for all their customers, and (3) load control devices at customer locations. Sudbury Hydro`s partners include AT and T Canada, Cisco, ICS and sureNet, the Sudbury Regional Network which is a consortium of 21 health, education, municipal and industry stakeholders. In the future, Sudbury Hydro will offer services such as cable television programming, movie videos on demand, telephone and access to the INTERNET. Beyond the direct benefits to consumers, the city of Sudbury will also benefit significantly from the building of this network.

  19. REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

    OpenAIRE

    Beata Janowska

    2016-01-01

    The sewage sludge disposal and cultivation methods consist in storage, agricultural use, compost production, biogas production or heat treatment. The sewage sludge production in municipal sewage sludge treatment plants in year 2013 in Poland amounted to 540.3 thousand Mg d.m. The sewage sludge for agricultural or natural use must satisfy chemical, sanitary and environmental safety requirements. The heavy metal content, including the mercury content, determines the sewage sludge disposal metho...

  20. Aquatic worm reactor for improved sludge processing and resource recovery

    OpenAIRE

    Hendrickx, T.L.G.

    2009-01-01

    Municipal waste water treatment is mainly achieved by biological processes. These processes produce huge volumes of waste sludge (up 1.5 million m3/year in the Netherlands). Further processing of the waste sludge involves transportation, thickening and incineration. A decrease in the amount of waste sludge would be both environmentally and economically attractive. Aquatic worms can be used to reduce the amount of waste sludge. After predation by the worms, the amount of final sludge is lower....

  1. Patterns of place promotion, place marketing and/or place branding in Dutch municipalities

    NARCIS (Netherlands)

    Boisen, Martin; Groote, Peter; Terlouw, Kees; Couwenberg, Oscar

    This paper analyses the different degrees to which place promotion, marketing and branding policies are institutionalised, based on a relatively straightforward and generally applicable methodology in order to stimulate international comparative research in the field. A consensus has emerged over

  2. Long-term market prospects/demand for seawater desalination for municipal supply

    International Nuclear Information System (INIS)

    Furukawa, D.H.; Zimerman, Z.

    1996-01-01

    The current status of the seawater desalination market was reviewed, and the expected evolution of installed capacities up to the year 2015 was projected in five year intervals by: Individual countries; unit size; desalination process used. 2 refs, 2 figs

  3. Microbial community composition of a down-flow hanging sponge (DHS) reactor combined with an up-flow anaerobic sludge blanket (UASB) reactor for the treatment of municipal sewage.

    Science.gov (United States)

    Kubota, Kengo; Hayashi, Mikio; Matsunaga, Kengo; Iguchi, Akinori; Ohashi, Akiyoshi; Li, Yu-You; Yamaguchi, Takashi; Harada, Hideki

    2014-01-01

    The microbial community composition of a down-flow hanging sponge (DHS) reactor in an up-flow anaerobic sludge blanket (UASB)-DHS system used for the treatment of municipal sewage was investigated. The clone libraries showed marked differences in microbial community composition at different reactor heights and in different seasons. The dominant phylotypes residing in the upper part of the reactor were likely responsible for removing organic matters because a significant reduction in organic matter in the upper part was observed. Quantification of the amoA genes revealed that the proportions of ammonia oxidizing bacteria (AOB) varied along the vertical length of the reactor, with more AOB colonizing the middle and lower parts of the reactor than the top of the reactor. The findings indicated that sewage treatment was achieved by a separation of microbial habitats responsible for organic matter removal and nitrification in the DHS reactor. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 2: Evaluation of ash materials as phosphorus fertilizer

    DEFF Research Database (Denmark)

    Thomsen, Tobias Pape; Hauggaard-Nielsen, Henrik; Gøbel, Benny

    2017-01-01

    to the mono-sludge ashes, thereby showing the best fertilizer qualities among all assessed materials. It was also found that bottomashes from the char reactor contained even less heavy metals than cyclone ashes. It is concluded thatLT-CFB gasification and co-gasification is a highly effective way to purify...

  5. Radiation hygienization of raw sewage sludge

    International Nuclear Information System (INIS)

    Shah, M.R.; Lavale, D.S.; Rawat, P.; Benny, P.G.; Sharma, A.K.; Dey, G.R.; Bhave, V.

    2001-01-01

    'Radiation treatment of municipal sewage sludge can achieve resource conservation and recovery objectives. The liquid sludge irradiator of Sludge Hygienization Research Irradiator at Baroda (India) was operated for generating data on treatment of raw sludge containing 3-4 % solids. The plant system was modified for irradiating raw sludge without affecting basic irradiator initially designed to treat digested sludge. Hourly samples were analysed for estimation of disinfection dose requirement. Sand separated from the sludge was used as in-situ dosimeter by making use of its thermoluminescence property. Investigations are being carried out for regrowth of Total Coliforms in the sludge samples from this irradiator. Possibility of inadequate treatment due to geometric configuration of irradiator is being checked. (author)

  6. Sewage sludge as a biomass resource for the production of energy: Overview and assessment of the various options

    NARCIS (Netherlands)

    Rulkens, W.H.

    2008-01-01

    Treatment of municipal wastewater results worldwide in the production of large amounts of sewage sludge. The major part of the dry matter content of this sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary (microbiological) sludge. The sludge also

  7. Below and above boiling point comparison of microwave irradiation and conductive heating for municipal sludge digestion under identical heating/cooling profiles.

    Science.gov (United States)

    Hosseini Koupaie, E; Eskicioglu, C

    2015-01-01

    This research provides a comprehensive comparison between microwave (MW) and conductive heating (CH) sludge pretreatments under identical heating/cooling profiles at below and above boiling point temperatures. Previous comparison studies were constrained to an uncontrolled or a single heating rate due to lack of a CH equipment simulating MW under identical thermal profiles. In this research, a novel custom-built pressure-sealed vessel which could simulate MW pretreatment under identical heating/cooling profiles was used for CH pretreatment. No statistically significant difference was proven between MW and CH pretreatments in terms of sludge solubilization, anaerobic biogas yield and organics biodegradation rate (p-value>0.05), while statistically significant effects of temperature and heating rate were observed (p-value<0.05). These results explain the contradictory results of previous studies in which only the final temperature (not heating/cooling rates) was controlled. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. The nitrite-oxidizing community in activated sludge from a municipal wastewater treatment plant determined by fatty acid methyl ester-stable isotope probing.

    Science.gov (United States)

    Kruse, Myriam; Zumbrägel, Sabine; Bakker, Evert; Spieck, Eva; Eggers, Till; Lipski, André

    2013-10-01

    Metabolically-active autotrophic nitrite oxidizers from activated sludge were labeled with (13)C-bicarbonate under exposure to different temperatures and nitrite concentrations. The labeled samples were characterized by FAME-SIP (fatty acid methyl ester-stable isotope probing). The compound cis-11-palmitoleic acid, which is the major lipid of the most abundant nitrite oxidizer in activated sludge, Candidatus Nitrospira defluvii, showed (13)C-incorporation in all samples exposed to 3 mM nitrite. Subsequently, the lipid cis-7-palmitoleic acid was labeled, and it indicated the activity of a nitrite oxidizer that was different from the known Nitrospira taxa in activated sludge. The highest incorporation of cis-7-palmitoleic acid label was found after incubation with a nitrite concentration of 0.3 mM at 17 and 22°C. While activity of Nitrobacter populations could not be detected by the FAME-SIP approach, an unknown nitrite oxidizer with the major lipid cis-9 isomer of palmitoleic acid exhibited (13)C-incorporation at 28°C with 30 mM nitrite. These results indicated flexibility of nitrite-oxidizing guilds in a complex community responding to different conditions. Labeled lipids so far not described for activated sludge-associated nitrifiers indicated the presence of unknown nitrite oxidizers in this habitat. The FAME-SIP-based information can be used to define appropriate conditions for the enrichment of nitrite-oxidizing guilds from complex samples. Copyright © 2013 Elsevier GmbH. All rights reserved.

  9. Domestic sludge and fish pond effluents in the municipality of Pentecoste, Ceará State, Brazil - doi: 10.4025/actascitechnol.v34i4.12004

    Directory of Open Access Journals (Sweden)

    Marcelo Vinícius do Carmo e Sá

    2012-10-01

    Full Text Available The present work aimed to compare the physical and chemical quality of domestic sludge in the city of Pentecoste, State of Ceará, Brazil, to fish pond effluents from the Aquaculture Research Center of the Departamento Nacional de Obras Contras as Secas – DNOCS, located in the same city. The work was carried out in Pentecoste (State of Ceará, Brazil in three sampling campaigns, with 30-day intervals between them. In each campaign, four samples were collected at different points of the following sites: (1 fish pond supply channel from the Aquaculture Research Center (CPAq of the DNOCS; (2 fish pond drainage channel of CPAq/DNOCS; (3 tap water from four homes in Pentecoste; and (4 domestic sludge channel of Pentecoste. In the lab, samples were analyzed for dissolved oxygen, total ammonia, free CO2, nitrite, reactive phosphorus, electric conductivity and chemical oxygen demand (COD, following standard methods. It was concluded that Pentecoste’s domestic sludge has a much stronger eutrophication impact on the receiving water than that caused by the CPAq/DNOCS’s fish pond effluents.

  10. Estimation of the electric power potential using wastewater sludge produced from the Percy Steward Wastewater Treatment Works (PS-WWTW) in Mogale City local municipality

    CSIR Research Space (South Africa)

    Mema, V

    2015-06-01

    Full Text Available at PS-WWTW in Mogale City local municipality indicates that high energy savings potential compared to using energy from fossil fuels. Analysis of the annual energy (electricity) consumption at the PS-WWTW over the past 3 years (2011 – 2014) shows...

  11. The chemical and mechanical differences between alginate-like exopolysaccharides isolated from aerobic flocculent sludge and aerobic granular sludge

    NARCIS (Netherlands)

    Lin, Y. M.; Sharma, P. K.; van Loosdrecht, M. C. M.

    2013-01-01

    This study aimed to investigate differences in the gel matrix of aerobic granular sludge and normal aerobic flocculent sludge. From both types of sludge that fed with the same municipal sewage, the functional gel-forming exopolysaccharides, alginate-like exopolysaccharides, were isolated. These two

  12. International Best Practices for Pre-Processing and Co-Processing Municipal Solid Waste and Sewage Sludge in the Cement Industry

    Energy Technology Data Exchange (ETDEWEB)

    Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Williams, Christopher [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-07-01

    The purpose of this report is to describe international best practices for pre-processing and coprocessing of MSW and sewage sludge in cement plants, for the benefit of countries that wish to develop co-processing capacity. The report is divided into three main sections. Section 2 describes the fundamentals of co-processing, Section 3 describes exemplary international regulatory and institutional frameworks for co-processing, and Section 4 describes international best practices related to the technological aspects of co-processing.

  13. Municipal water pollution prevention program

    International Nuclear Information System (INIS)

    1991-03-01

    EPA believes that the most effective and equitable means of assuring viability of this infrastructure is through environmentally preferred pollution prevention approaches especially through application of Municipal Water Pollution Prevention (MWPP). These approaches may enhance worker safety, improve the usability of sludge, increase the ability for local community expansion, and reduce operation and compliance costs. State-based municipal pollution prevention programs focus attention on a series of actions to prevent pollution in advance rather than taking more expensive corrective actions. MWPP encourages resource conservation to reduce water and energy use, appropriate pricing, toxicity reductions at the source, BOD reductions, recycling, proper treatment of wastes, and beneficial uses of sludge

  14. Between marketing and financial support : Dutch municipal policy instruments to improve the quality of private housing stock

    NARCIS (Netherlands)

    Tambach, M.; Meijer, F.; Visscher, H.

    2011-01-01

    Dutch municipalities are faced with an ageing private housing stock, of which parts show a diversity of quality backlogs, including their energy quality. Dutch municipalities are in the process of developing a combination of communicative and economic policy instruments to seduce private homeowners

  15. Bio-adsorption (Pilot-scale). Investigation of cleansing effect and sludge formation. [Municipal wastes]. Biosorption. Pilot-skala. Undersoegelse af renseeffekt og slamudbytte

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-15

    The aim of the project was to investigate the process of bioadsorption in relation to the purifying of sewage waste where the oxygen levels were 0%, 2.5% and 10%. Cleansing results for 2.5% oxygen saturation was 50-70% for BOD and 30-50% for COD. Reduction of nitrogen and phosphorus was 15-20% and 20-25%. 40% of the removed nitrogen, and the organic bound phosphorus, was returned to the system via the internal reject-flow and thus to the biological processing. The tendence to sludge production was heightened where oxygen saturation was moderate. It is reckoned that operational costs were reduced by 10 Danish oere per cubic meter waste water where the unprocessed waste had a content of 250mg BOD/1. (AB).

  16. Neurociencias al servicio del marketing en la gestión municipal en el sur del departamento de La Guajira

    Directory of Open Access Journals (Sweden)

    Luis Roberto Alguero

    2018-04-01

    Full Text Available Las neurociencias y sus diversas aplicaciones en el pleno siglo XXI plantean desafíos del conocimiento con mucha valía a distintas disciplinas que se despliegan incluso hasta las ciencias gerenciales, en virtud de sus aportes. Aunado a ello, dichos procesos tienen cabida en la administración, la gestión pública municipal, esencialmente porque requieren de la planificación, sobre todo si se tienen en cuenta los contextos variables y de incertidumbre que se experimentan en la actualidad, a fin de desarrollar posteriormente un conjunto de actividades determinantes que permita el cumplimiento de los objetivos según las líneas de acción propuestas. Con respecto a lo anterior Braidot (2009 señala que el Neuromarketing es una disciplina de avanzada, que tiene como función investigar y estudiar procesos cerebrales que hacen de una manera más clara la conducta y toma de decisiones de las personas en los campos de acción de marketing tradicional (inteligencia de mercado, diseño de productos y servicios, comunicaciones, precios, posicionamiento, targeting, canales, ventas, fidelización. Metodológicamente la investigación responde al enfoque cualitativo desde el método etnográfico perfilado en el paradigma epistémico es introspectivo vivencial. En cuanto a la recolección de datos se realizó a través de observación y entrevistas semiestructuradas, que dieron paso a la estructuración del proceso cognitivo mediante los memorandos y la integración del mismo junto a la triangulación. Lo anterior facilitó el cumplimiento del propósito general; comprensión de las categorías y a su vez al derivado; generar unos lineamientos teóricos sustantivos.

  17. Wasting Away: To Sludge or Not to Sludge?

    Directory of Open Access Journals (Sweden)

    L Nicolle

    2001-01-01

    Full Text Available Following a century of high standards of sanitation, food and water safety in North America are often taken for granted. Recent outbreaks of illness attributed to food and water contamination, however, have challenged this complacency. Now, sludge is added to the list of concerns. Sewage sludge is the muddy substance that remains after the treatment of municipal sewage. This material includes not only human waste, but also household and industrial toxic wastes disposed of in local sewers. Federal and provincial Canadian regulations support the use of this material as fertilizer, within acceptable guidelines, as does the Environmental Protection Agency in the United States. The safety of sludge, however, is questioned by some individuals and groups. Specifically, the risk of infectious agents and toxins to workers or other exposed individuals, and the potential for heavy metals and organic chemicals to be transferred from sludge-treated fields into crops are concerns.

  18. Technical-economical, agronomical, pedological, hygienic and normative aspects of municipal wastewater sludges; Aspetti tecnico-economici, agronomici, pedologici, igienico-sanitari e normativi dei fanghi di depurazione civile

    Energy Technology Data Exchange (ETDEWEB)

    Ottavi, C [ENEA, Rome (Italy). Dip. Ambiente; Ottaviani, M [Istituto Superiore di Sanita, Rome (Italy). Lab. di Igiene Ambientale; Figliolia, A [Istituto Sperimentale per la Nutrizione delle Piante, Rome (Italy)

    1995-12-01

    This review is intended to give an overview on the technical, economical, agronomical, pedological and hygienic aspects of sludges from treatment plants of civil wastewater, Both Italian and European regulations on the sludge disposal are considered.

  19. Municipal opportunities

    International Nuclear Information System (INIS)

    Cousens, D.; Chuddy, B.; Gleeson, A.; Leckie, D.; Wahl, K.; McGarry, D.

    1997-01-01

    The panel discussing market opportunities for municipal electric companies was moderated by Markham Mayor Don Cousens. He expressed himself in favour of deregulation and was optimistic about the benefits it will bring to municipal electric utilities and their customers. Barry Chuddy, General Manager of Business Development for TransAlta Energy discussed the advantages of recent cogeneration and district energy for municipal utilities in Ontario and Quebec, and expressed his support for incentive-based regulation based on a level playing field, competitive generation, and a reasonable charge for stranded assets. Toronto City Councillor Dan Leckie described cogeneration and district energy as a tremendous opportunity to reduce the cost of doing business in the city core through local job creation and by keeping money in the local economy. Karl Wahl, General Manager of Hydro Mississauga expressed optimism that the government will move expeditiously toward competition, choice and lower-cost supply. David McGarry, President of Elecsar Engineering of Sarnia spoke about the significant job creating potential that deregulation will bring to the electrical industry. He cited several examples from Ontario and British Columbia

  20. Environmental sustainability of wastewater sludge treatments

    DEFF Research Database (Denmark)

    Boyer-Souchet, Florence; Larsen, Henrik Fred

    treatment for municipal waste water. A special focus area in Neptune is sludge handling because the sludge amount is expected to increase due to advanced waste water treatment. The main sludge processing methods assessed in Neptune can be divided into two categories: disintegration processes before...... anaerobic digestion (thermal hydrolysis and ultrasound disintegration) and inertisation processes performed at high temperatures (incineration, pyrolysis, gasification, wet oxidation) but they all aim at volume reduction and removal of biodegradable compounds before safe sludge disposal or reuse of its...... resources. As part of a sustainability assessment (or “best practice evaluation”), a comparison between the existing and new sludge handling techniques have been done by use of life cycle assessment (LCA).The concept of induced impacts as compared to avoided impacts when introducing a new sludge treatment...

  1. A vermicompostagem do lodo de lagoas de tratamento de efluentes industriais consorciada com composto de lixo urbano The vermicomposting of an industrial sludge combined with a compost of municipal solid refuse

    Directory of Open Access Journals (Sweden)

    Luciana Rodrigues Valadares Veras

    2004-09-01

    Full Text Available A destinação dos resíduos sólidos constitui um sério problema ambiental para a humanidade, principalmente em regiões de grande concentração urbana, onde a disponibilidade de áreas para disposição dos rejeitos é quase sempre restrita. Com a intenção de fornecer mais uma alternativa para solução do problema, desenvolveu-se um estudo para avaliar a vermicompostagem de um lodo industrial, resultante do processamento de frutas, consorciado com composto de lixo urbano. Através desse processo, pode-se obter a reciclagem dos resíduos, produzindo-se um composto denominado húmus ou vermicomposto. Dentre os resultados obtidos pode-se destacar bons indicadores do nível de maturidade dos resíduos, representados pela relação carbono/nitrogênio, a influência da minhoca na elevação do pH e sua contribuição para uma estabilização mais acelerada da matéria orgânica.The final disposal of solid wastes is a serious environmental problem, mainly in big towns, where the areas to put the refuses on are not much available. To provide one more alternative to solve this problem, a research was developed to analyse the vermicomposting of industrial sludge combined with a compost of municipal solid refuse. By this process, it was possible to obtain the recycling of the wastes, producing a material called humus or vermicompost. The results showed good maturity levels of the refuses, presented by the carbon/nitrogen relations, the worms influence in the pH elevation and their possible acceleration of the organic material stabilization.

  2. Urban forests' potential to supply marketable carbon emission offsets: a survey of municipal governments in the United States

    Science.gov (United States)

    Neelam C. Poudyal; Jacek P. Siry; J. M. Bowker

    2010-01-01

    This study assesses the motivation, willingness, and technical as well as managerial capacities of U.S. cities to store carbon and sell carbon offsets. Based on a national survey of urban foresters, arborists, and other officials responsible for urban forest management within U.S. municipal governments, results indicate that local governments are interested in selling...

  3. Legislation concerning the energy reuse of sludge from waste water treatment plant in the region of Slovenia

    Energy Technology Data Exchange (ETDEWEB)

    Mislej, V. (Vodovod-Kanalizacija, Ljubljana (Slovenia)), Email: vmislej@vo-ka.si; Grilc, V. (National Inst. of Chemistry, Ljubljana (Slovenia)), Email: viktor.grilc@ki.si

    2009-07-01

    The legislation on waste management in Slovenia was markedly renovated in the year 2008. The main changes were related to the treatment of biologically degradable wastes, which was extended to the energy-from-waste option. New regulations in Slovenia have set criteria on which wastes can be processed and transformed into a solid recovered fuel and the conditions concerning its quality and use. The legislation also outlines other process conditions for placing sewage sludge on the market as a secondary solid fuel and its application in various thermal processes. Sewage sludge represents the largest share of wastes. generated at biological wastewater treatment plants (BWWTP). In fresh form it is formed as excess active sludge formed during biological treatment of municipal wastewater and may be consecutive stabilized by an aerobic or anaerobic process. Anaerobic stabilization (digestion)of the raw gravity thickened sludge, followed by mechanical and thermal dehydration transform the fresh sludge into stable dry granules. In this form it is suitable for marketing and utilization in thermal processes. The main problems may be low calorific value and relative high metals content (especially mercury) and sulphur. Sulphur and cadmium are not among the limiting parameters of the noted technical specification for alternative fuels, so the new regulation in Slovenia will be appealed. (orig.)

  4. Where to dispose of the sewage sludge?

    International Nuclear Information System (INIS)

    Beurer, P.; Geering, F.

    2001-01-01

    The 'proper' course for the disposal of sewage sludge is a topic that has continually sparked intense discussion for years. New legal regulations have developed which have significantly changed the disposal structure. Nevertheless, the consumer market of agriculture products has an increasing influence on sewage sludge recycling possibilities. In this report, the changes in sewage sludge disposal within the last ten years and the expected development is pointed out. On account of legal guidelines and of political market influences, the thermal recycling of sewage sludge is considered as the future solution, which should, however, be adapted according to marginal situations. (author)

  5. Restructuring of the electricity market. New general framework and management strategies for municipalities. Documentation of contributions to the IKU seminar; Strommarkt im Umbruch. Neue Rahmenbedingungen und Strategien fuer Kommunen. Veranstaltungsunterlagen

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, C. (comp.)

    2000-07-01

    The titles of the seven papers presented at the IKU seminar are as follows: 1. The emerging competitive electricity markets - Perspectives for municipalities. - 2. New supply offers and terms and conditions for power procurement of municipalities. - 3. Power procurement and awarding of contracts - legal framework and recommendations for municipalities in designing the tendering procedure in the competitive market environment. - 4. Experience of a municipality in the process of establishing a local pool of buyers. - 5. Experience obtained in defining new tender conditions and specifications for power supply to a municipal undertaking. - 6. Experience of a municipality obtained in negotiations with electricity supply undertakings. - 7. Invitations to tender for energy supply to municipalities - experience of the hessenENERGIE GmbH. (orig./CB) [German] Die Titel der in diesem Dokument abgedruckten sieben Beitraege zum IKU Seminar lauten: 1. Wettbewerb auf den Strommaerkten - Perspektiven fuer Kommunen. - 2. Neue Angebote und neue Konditionen fuer den Strombezug von Kommunen. - 3. Strombezug und Vergaberecht - Rechtlicher Rahmen und Empfehlungen zur Gestaltung der Vergabe bei oeffentlichen Auftraggebern. - 4. Erfahrungen mit der Bildung eines kommunalen Nachfragepools. - 5. Erfahrungen mit der Ausschreibung von Stromlieferungen fuer einen oeffentlichen Auftraggeber. - 6. Erfahrungen einer Kommune aus Verhandlungen ueber den Strombezug mit Versorgungsunternehmen. - 7. Ausschreibung von Energielieferungen fuer Kommunen - Erfahrungen und Angebote der hessenENERGIE GmbH. (orig./CB)

  6. 76 FR 823 - Registration of Municipal Advisors

    Science.gov (United States)

    2011-01-06

    ... financial products.\\12\\ For example, as derivatives have developed in the municipal securities market, some... public information regarding the size of the municipal securities derivative market. Estimates of the..., Municipal Derivative Securities--Uses and Valuation 21 (1995) (discussion of revenue bonds). See also...

  7. New trends in processing and disposal of municipal and industrial sewage sludges. 8. Joint seminar `waste water technology` with exhibitor`s forum; Neue Trends bei der Behandlung und Entsorgung kommunaler und industrieller Klaerschlaemme. Achtes gemeinsames Seminar `Abwassertechnik` mit Ausstellerforum

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The present conference proceedings handle all aspects of sewage sludge disposal: agricultural use of sewage sludge, processing in anaerobic reactors, composting, drain, drying, gasification, combustion, economical aspects, ecological aspects, building, design and operation of modern sludge treatment plants. (SR) [Deutsch] Der vorliegende Tagungsband behandelt alle Aspekte der Klaerschlammentsorgung: landwirtschaftliche Nutzung von Klaerschlamm, Behandlung in Anaerobreaktoren, Kompostierung, Entwaesserung, Trocknung, Vergasung, Verbrennung, wirtschaftliche Aspekte, oekologische Aspekte, Bau, Ausruestung und Betrieb von modernen Schlammbehandlungsanlagen. (SR)

  8. Characterization and distribution of esterase activity in activated sludge

    NARCIS (Netherlands)

    Boczar, BA; Forney, LJ; Begley, WM; Larson, RJ; Federle, TW

    2001-01-01

    The location and activity of esterase enzymes in activated Sludge from three Municipal wastewater treatment plants were characterized using model Substrate, and denaturing and nondenaturing polyacrylamide gel electrophoresis (PAGE) Of particulate, freeze thaw (primarily periplasmic enzymes and those

  9. Textile wastewater treatment: aerobic granular sludge vs activated sludge systems.

    Science.gov (United States)

    Lotito, Adriana Maria; De Sanctis, Marco; Di Iaconi, Claudio; Bergna, Giovanni

    2014-05-01

    Textile effluents are characterised by high content of recalcitrant compounds and are often discharged (together with municipal wastewater to increase their treatability) into centralized wastewater treatment plants with a complex treatment scheme. This paper reports the results achieved adopting a granular sludge system (sequencing batch biofilter granular reactor - SBBGR) to treat mixed municipal-textile wastewater. Thanks to high average removals in SBBGR (82.1% chemical oxygen demand, 94.7% total suspended solids, 87.5% total Kjeldahl nitrogen, 77.1% surfactants), the Italian limits for discharge into a water receiver can be complied with the biological stage alone. The comparison with the performance of the centralized plant treating the same wastewater has showed that SBBGR system is able to produce an effluent of comparable quality with a simpler treatment scheme, a much lower hydraulic residence time (11 h against 30 h) and a lower sludge production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Variation in VIP latrine sludge contents | Bakare | Water SA

    African Journals Online (AJOL)

    This study investigated variations in the characteristics of the sludge content from different ventilated improved pit (VIP) latrines and variation in these characteristics at specific depths within each pit. Faecal sludge from 16 VIP latrines within the eThekwini Municipality was collected and laboratory characterisation including ...

  11. Aquatic worm reactor for improved sludge processing and resource recovery

    NARCIS (Netherlands)

    Hendrickx, T.L.G.

    2009-01-01

    Municipal waste water treatment is mainly achieved by biological processes. These processes produce huge volumes of waste sludge (up 1.5 million m3/year in the Netherlands). Further processing of the waste sludge involves transportation, thickening and incineration. A decrease in the amount of waste

  12. Fate of linear alkylbenzene sulfonate (LAS) in activated sludge plants

    NARCIS (Netherlands)

    Temmink, B.G.; Klapwijk, A.

    2004-01-01

    Monitoring data were collected in a pilot-scale municipal activated sludge plant to assess the fate of the C12-homologue of linear alkyl benzene sulfonate (LAS-C12). The pilot-plant was operated at influent LAS-C12 concentrations between 2 and 12 mg/l and at sludge retention times of 10 and 27

  13. Sludge application and monitoring program on the Oak Ridge Reservation, 1986--1993

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, C.A.; Larsen, I.L.; Boston, H.L.; Bradburn, D.M. [Oak Ridge National Lab., TN (United States); Van Miegroet, H. [Utah State Univ., Logan, UT (United States). Dept. of Forest Resources; Morris, J.L. [Jaycor, Inc., Oak Ridge, TN (United States); Walzer, A.E. [Lockheed Martin Energy Systems, Oak Ridge, TN (United States). Central Environmental Compliance; Adler, T.C. [Bechtel National, Inc., Oak Ridge, TN (United States); Huq, M. [Oak Ridge Associated Universities, TN (United States)

    1995-09-01

    Municipal sewage sludge has been applied to forests and pastures on the Oak Ridge Reservation since 1983 as a method of both disposal and beneficial reuse. Application was carried out under Tennessee permits issued to the city of Oak Ridge for land disposal of sewage sludge. In conjunction with these applications, information has been collected concerning sludge quantity and characteristics, soil parameters, soil water constituents, groundwater quality, surface runoff water quality, and various chemical constituents in vegetation on application sites. This information provides (1) a record of sludge application on the DOE reservations and (2) documentation of changes in soil parameters following sludge application. The information also provides a basis for evaluating the implications of the land application of municipal sewage sludge for soil and water quality and for evaluating the fate of sludge constituents when sludge is either sprayed or injected on pasture sites or surface applied in forested sites. This report covers in detail sludge applications conducted from 1986 through 1993, with some data from the period between 1983 and 1986. Anaerobically digested liquid sludge (2% to 4% solids) from the city of Oak Ridge had a relatively high nitrogen content (8% dry weight) and average to low concentrations of potentially problematic metals, compared with typical municipal sludges. Few potentially hazardous organic chemicals were detected in the sludge, and when found, these were at very low concentrations. Oak Ridge sludge is somewhat unique in that it contains radionuclides ({sup 137}Cs, {sup 60}Co, {sup 131}I, uranium isotopes, {sup 90}Sr, and occasionally {sup 99}Tc) at concentrations much higher than typical municipal sludges. Land application of sewage sludge can dilute or destroy problematic sludge constituents while improving soil fertility. Correct management has made these sludge applications a model of environmentally responsible waste management.

  14. The cultural and tourist policy dimension in city marketing: the case of the olympic municipality of Nea Ionia, Magnesia, Greece

    OpenAIRE

    Deffner, Alex; Metaxas, Theodore

    2008-01-01

    Culture and tourism have been used extensively in a variety of initiatives that concern urban regeneration, by using particular promotional strategies and tactics in the context of city marketing. The contribution of culture and tourism must be related to the conformance and implementation of urban policy actions, the focus on the satisfaction of the needs and demands of the potential target markets, the enforcement and promotion of the urban cultural identity and image, the contribution of c...

  15. Effect of seed sludge on characteristics and microbial community of aerobic granular sludge.

    Science.gov (United States)

    Song, Zhiwei; Pan, Yuejun; Zhang, Kun; Ren, Nanqi; Wang, Aijie

    2010-01-01

    Aerobic granular sludge was cultivated by using different kinds of seed sludge in sequencing batch airlift reactor. The influence of seed sludge on physical and chemical properties of granular sludge was studied; the microbial community structure was probed by using scanning electron microscope and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that seed sludge played an important role on the formation of aerobic granules. Seed sludge taken from beer wastewater treatment plant (inoculum A) was more suitable for cultivating aerobic granules than that of sludge from municipal wastewater treatment plant (inoculum B). Cultivated with inoculum A, large amount of mature granules formed after 35 days operation, its SVI reached 32.75 mL/g, and SOUR of granular sludge was beyond 1.10 mg/(g x min). By contrast, it needed 56 days obtaining mature granules using inoculum B. DGGE profiles indicated that the dominant microbial species in mature granules were 18 and 11 OTU when inoculum A and B were respectively employed as seed sludge. The sequencing results suggested that dominant species in mature granules cultivated by inoculum A were Paracoccus sp., Devosia hwasunensi, Pseudoxanthomonas sp., while the dominant species were Lactococcus raffinolactis and Pseudomonas sp. in granules developed from inoculum B.

  16. The effects of pelleted sewage sludge on Norway spruce establishment and nitrogen dynamics

    International Nuclear Information System (INIS)

    Johannesson, Anders

    1999-01-01

    In Sweden there is a big resource in unutilised sewage sludge. Studies have shown that application of municipal sewage sludge can improve forest productivity and planting environment. This study is examining the effects of two types of pelleted sewage sludge (pure sludge and a mixture of sludge and domestic wastes compost) on nitrogen turnover. Large differences were found in the fertilisation effect of the different treatments. The pure sewage sludge pellets treatment showed significant increases for NH 4 -accumulation, nitrification and NO 3 -leaching in the top 10 cm of the soil. Uptake of nitrogen was increased in spruce plants and vegetation. The mixed sludge/domestic waste pellets treatment showed indications of a minor initial release of nitrogen. This is seen as a small but significant initial increase in soil nitrification. These results suggest that the pure sewage sludge pellet is an adequate nitrogen fertiliser. The mixed sludge though is inadequate at least in the short run

  17. Comment on "Synergistic co-digestion of solid-organic-waste and municipal-sewage-sludge: 1 plus 1 equals more than 2 in terms of biogas production and solids reduction" [Water Research 87, 416-423].

    Science.gov (United States)

    Insam, Heribert; Markt, Rudolf

    2016-05-15

    Co-digestion of organic waste and sewage sludge enhances biogas production and reduces the mass of remaining solids. This phenomenon of enhanced organic matter decomposition by adding labile substrate is known from other habitats like soils and sediments where it is called priming effect. It is thus suggested to adopt the term priming effect also in environmental biotechnology, and in particular for biomethanisation of wastewater sludges by the addition of energy-rich co-substrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Radioactivity of sludge in Finland in 1987

    International Nuclear Information System (INIS)

    Puhakainen, M.; Rahola, T.

    1989-05-01

    Sewage sludge from municipal wastewater treatment plants was studied to determine its radionuclide concentrations. Measurements were made to find out whether any radionuclides from the nuclear power stations at Loviisa and Olkiluoto and from hospitals and medical laboratories could be detected in sludge additional to those originating from global and Chernobyl fallout. In the treatment process of water, aluminium sulphate sludge is developed at treatment plants using surface water. This kind of sludge was measured since it also concentrates radionuclides. Fallout nuclides from the Chernobyl nuclear power station after the accident predominated in all sewage sludge samples in Finland. In 1987 six different radionuclides originating from the Chernobyl fallout were detected in sewage sludge. In spring when the snow melted and large quantities of run off water flowed into the treatment plants, the activity concentrations clearly increased, but then started decreasing again. At the end of the year the highest measured 137 Cs activity concentrations were below 1000 Bq kg -1 dry weight. The highest activity concentration in sludge originated from iodine used fro medical purposes

  19. Intensification of anaerobic digestion efficiency with use of mechanical excess sludge disintegration in the context of increased energy production in wastewater treatment plants

    OpenAIRE

    Żubrowska-Sudoł Monika; Podedworna Jolanta; Bisak Agnieszka; Sytek-Szmeichel Katarzyna; Krawczyk Piotr; Garlicka Agnieszka

    2017-01-01

    The main goal of the study was to evaluate the effects of mechanical sludge disintegration for enhancing full scale anaerobic digestion of municipal sludge. Batch disintegration tests and lab dewatering tests were also performed aiming at determining the release of organic compounds and assessing the impact of disintegration of excess sludge before the fermentation process of mixed sludge on the dewaterability of post-fermented sludge, respectively. In the study a disc disintegrator driven by...

  20. Sludge application and monitoring program on the Oak Ridge Reservation, 1986 through 1993

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, C.A.; Boston, H.L.; Van Miegroet, H., Morris, J.L.; Larsen, I.L.; Walzer, A.E.; Adler, T.C.; Bradburn, D.M.; Huq, M.

    1995-08-01

    Municipal sewage sludge has been applied to forests and pastures on the DOE (U.S. Department of Energy) Oak Ridge Reservation (ORR) since 1983 as a method of both disposal and beneficial reuse. Application was carried out under State of Tennessee permits issued to the City of Oak Ridge for land disposal of. sewage sludge. In conjunction with these applications, information has been collected concerning sludge quantity and characteristics, soil parameters, soil water constituents, groundwater quality, surface runoff water quality, and various chemical constituents in vegetation on application sites. This information provides (1) a record of sludge application on the DOE ORR, and (2) documentation of changes in soil parameters following sludge application. The information also provides a basis for evaluating the implications of the land application of municipal sewage sludge for soil and water quality and for evaluating the fate of sludge constituents when sludge is either sprayed onto or injected into pasture sites or applied to the surface of forested sites. This report covers in detail sludge applications conducted from 1986 through 1993, with some data from the period between 1983 and 1986. Land application has been recommended by the U.S. Environmental Protection Agency as a desirable alternative for disposal of ORR waste. Municipal sewage sludge is in many ways similar to dilute animal manure fertilizer, but it also contains metals, organic chemicals, human pathogens, and other constituents reflective of inputs into the municipal sewage treatment plant. When applied to land, nutrients in the sludge improve soil fertility, and minerals and organic matter in the sludge improve soil structure. Under optimal conditions, metals are immobilized, and organic chemicals and pathogens are immobilized or destroyed. If the sludge is not managed effectively, however, sludge constituents have the potential to affect human health and the environment.

  1. Sludge busters

    International Nuclear Information System (INIS)

    Pichon, Max

    2010-01-01

    Full text: A few years ago, For Earth developed low energy sub-surface aeration systems to increase the biological activity in the wastewater sludge ponds. Then came the idea to introduce probiotic bacteria to really ramp up the process, which promises massive time and cost savings in sludge management. Increasing the volumes of specific bacteria reactivates the sludge, accelerating biological nutrient removal in general and, by tailoring the bacteria, targeting specific organic waste types. The technology is already running at more than 30 councils across NSW and in some commercial settings, such as dairy farms. Shane McKibbin, GM of For Earth, said the 'Probiotic, Low Energy Aeration System' offers considerable upside. “The cost savings have been enormous with some councils, including the work done at Woolgoolga Water Reclamation Plant at Coffs Harbour,” he said. Sludge settling in wastewater treatment plant lagoons is typically pumped out, centrifuged to remove water and then landfilled. In Woolgoolga's case that process was costing Coffs Harbour Water $150 a cubic metre; McKibbin said they've slashed that to a measly $5 a cubic metre. An array of 'industrial air stones' is dropped 1m below the surface to create an oxygenated blanket across the surface, overcoming the tendency of sludge ponds to stagnate. The key though is floating probiotic dosing lines across the surface, which kick-starts the probiotics process. “Previously, some operators just wanted to throw it on with a bucket, so the bacteria would get thrown into one corner of the pond. But since we introduced the dosing system it has really improved the overall performance,” said McKibbin.The dosing pump system automatically applies the bacteria into the dosing line according to a specified program, ensuring the probiotics are spread out across the pond and across the week. “I would say it improves and accelerates the result by 30 per cent,” he adds. “The biggest problem was that

  2. Sludge busters

    Energy Technology Data Exchange (ETDEWEB)

    Pichon, Max

    2010-07-15

    Full text: A few years ago, For Earth developed low energy sub-surface aeration systems to increase the biological activity in the wastewater sludge ponds. Then came the idea to introduce probiotic bacteria to really ramp up the process, which promises massive time and cost savings in sludge management. Increasing the volumes of specific bacteria reactivates the sludge, accelerating biological nutrient removal in general and, by tailoring the bacteria, targeting specific organic waste types. The technology is already running at more than 30 councils across NSW and in some commercial settings, such as dairy farms. Shane McKibbin, GM of For Earth, said the 'Probiotic, Low Energy Aeration System' offers considerable upside. “The cost savings have been enormous with some councils, including the work done at Woolgoolga Water Reclamation Plant at Coffs Harbour,” he said. Sludge settling in wastewater treatment plant lagoons is typically pumped out, centrifuged to remove water and then landfilled. In Woolgoolga's case that process was costing Coffs Harbour Water $150 a cubic metre; McKibbin said they've slashed that to a measly $5 a cubic metre. An array of 'industrial air stones' is dropped 1m below the surface to create an oxygenated blanket across the surface, overcoming the tendency of sludge ponds to stagnate. The key though is floating probiotic dosing lines across the surface, which kick-starts the probiotics process. “Previously, some operators just wanted to throw it on with a bucket, so the bacteria would get thrown into one corner of the pond. But since we introduced the dosing system it has really improved the overall performance,” said McKibbin.The dosing pump system automatically applies the bacteria into the dosing line according to a specified program, ensuring the probiotics are spread out across the pond and across the week. “I would say it improves and accelerates the result by 30 per cent,” he adds. “The biggest problem was that

  3. An assessment of the economics and market opportunities for municipal solid waste fired combined heat and power applications

    International Nuclear Information System (INIS)

    Frith, D.P.; Toothill, S.J.

    1995-01-01

    This study examines the issues surrounding the development of CHP applications of MSW combustion plants, and in particular the opportunities for new projects. The specific objectives of the study were as follows: (i) To assess the economics of CHP applications of MSW plant at three scales of operation, with waste throughputs of 400,000, 200,000 and 100,000 tonnes per year. (ii) To report on the market opportunities and barriers to implementation for such applications in the UK. (iii) To report on the commercial development of three such applications (case studies) in the UK and to examine the environmental benefits of such applications, with particular respect to greenhouse gas emissions. (author)

  4. Considerations in the public acceptance of sewage sludge irradiation systems

    International Nuclear Information System (INIS)

    Dix, G.P.

    1975-01-01

    Considerations associated with public acceptance of municipal sewage sludge irradiation systems are discussed including the benefit to society, public information and safeguards. Public acceptance of products is based upon the benefit to society as measured by reduced consumer costs, minimization of public risk and enhancement of the quality of life and the environment. When viewed in this positive light, the sludge irradiator has high potential benefits to the community. If large-scale engineering experiments show that sludge irradiation is more cost-effective than other methods, reduced consumer costs would result. Today many sewage plants do not consistently remove pathogens from sludge; sludge irradiation could be an effective method of pathogen removal and result in avoidance of a major public risk. The sludge irradiator may be able to clean up recreational areas, reduce noxious odours from sewage treatment facilities, and reduce the energy requirements for producing fertilizer and soil conditioners and conserve their mineral content. Plant safeguards must be explained to dispel public concern that the contents of the source can be released to the sludge accidentally. This will be the main issue within the technical sector of the public, and the design, procedural and administrative safeguards of the plant must be fully explained. The primary risk associated with sludge irradiators will be the remote possibility of source leakage into the sludge. The various safeguards in sludge irradiation plants are discussed in detail including the form of the radionuclide, encapsulation, the irradiation chamber, safeguards instrumentation, shielding and thermal safeguards. (Author)

  5. Impact of solid retention time and nitrification capacity on the ability of activated sludge to remove pharmaceuticals

    DEFF Research Database (Denmark)

    Falås, Per; Andersen, Henrik Rasmus; Ledin, Anna

    2012-01-01

    Removal of five acidic pharmaceuticals (ibuprofen, ketoprofen, naproxen, diclofenac and clofibric acid) by activated sludge from five municipal activated sludge treatment processes, with various sludge ages and nitrification capacities, was assessed through batch experiments. The increase...... in aerobic sludge age from 1-3 to 7 days seemed to be critical for the removal of naproxen and ketoprofen, with markedly higher rates of removal at sludge ages of 7 days or more. No removal was shown for diclofenac and clofibric acid, while high rates were observed for ibuprofen in all investigated sludges...

  6. Study on improvement of sludge dewaterability with H2O2 cell lysis

    Science.gov (United States)

    Zhuo, Qiongfang; Yi, Hao; Zhang, Zhengke; Wang, Ji; Feng, Lishi; Xu, Zhencheng; Guo, Qingwei; Jin, Zhong; Lan, Yongzhe

    2017-12-01

    Excess sludge is the product of sewage treatment plants. With continuous perfection of municipal sewage treatment facilities in China, sludge output increases as a result of the growth of sewage treatment plants. Excess sludge has complicated compositions, including heavy metals, PPCPs, persistent organic pollutants. It owns high contents of organic matters and water. High-efficiency and low-cost dehydration of sludge is the key of sludge disposal. How to improve sludge dehydration efficiency is the research hotspot in the world. In this study, effects of hydrogen peroxide content and pH on sludge dehydration were discussed by chemical disintegration technique. The optimal hydrogen peroxide content and pH were discussed, aiming to search a high-efficiency sludge conditioner.

  7. Synergistic co-digestion of solid-organic-waste and municipal-sewage-sludge: 1 plus 1 equals more than 2 in terms of biogas production and solids reduction.

    Science.gov (United States)

    Aichinger, Peter; Wadhawan, Tanush; Kuprian, Martin; Higgins, Matthew; Ebner, Christian; Fimml, Christian; Murthy, Sudhir; Wett, Bernhard

    2015-12-15

    Making good use of existing water infrastructure by adding organic wastes to anaerobic digesters improves the energy balance of a wastewater treatment plant (WWTP) substantially. This paper explores co-digestion load limits targeting a good trade-off for boosting methane production, and limiting process-drawbacks on nitrogen-return loads, cake-production, solids-viscosity and polymer demand. Bio-methane potential tests using whey as a model co-substrate showed diversification and intensification of the anaerobic digestion process resulting in a synergistical enhancement in sewage sludge methanization. Full-scale case-studies demonstrate organic co-substrate addition of up to 94% of the organic sludge load resulted in tripling of the biogas production. At organic co-substrate addition of up to 25% no significant increase in cake production and only a minor increase in ammonia release of ca. 20% have been observed. Similar impacts were measured at a high-solids digester pilot with up-stream thermal hydrolyses where the organic loading rate was increased by 25% using co-substrate. Dynamic simulations were used to validate the synergistic impact of co-substrate addition on sludge methanization, and an increase in hydrolysis rate from 1.5 d(-1) to 2.5 d(-1) was identified for simulating measured gas production rate. This study demonstrates co-digestion for maximizing synergy as a step towards energy efficiency and ultimately towards carbon neutrality. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Sludge storage lagoon biogas recovery and use

    Energy Technology Data Exchange (ETDEWEB)

    Muller, D.; Norville, C. (Memphis and Shelby County Div. of Planning and Development, TN (United States))

    1991-07-01

    The City of Memphis has two wastewater treatment plants. The SWTP employs two large anaerobic digestion sludge lagoons as part of the overall sludge treatment system. Although these lagoons are effective in concentrating and digesting sludge, they can generate offensive odors. The SWTP uses aerobic digesters to partially stabilize the sludge and help reduce objectionable odors before it enters the lagoons. The anaerobic digestion of sludge in the lagoons results in the dispersion of a large quantity of biogas into the atmosphere. The City realized that if the lagoons could be covered, the odor problem could be resolved, and at the same, time, biogas could be recovered and utilized as a source of energy. In 1987, the City commissioned ADI International to conduct a feasibility study to evaluate alternative methods of covering the lagoons and recovering and utilizing the biogas. The study recommended that the project be developed in two phases: (1) recovery of the biogas and (2) utilization of the biogas. Phase 1 consists of covering the two lagoons with an insulated membrane to control odor and temperature and collect the biogas. Phase 1 was found to be economically feasible and offered a unique opportunity for the City to save substantial operating costs at the treatment facility. The Memphis biogas recovery project is the only application in the world where a membrane cover has been used on a municipal wastewater sludge lagoon. It is also the largest lagoon cover system in the world.

  9. Sludge recovery apparatus

    International Nuclear Information System (INIS)

    Marmo, A.R.

    1979-01-01

    Sludge recovery machine comprising a hollow centrifuge, a vertical pipe for feeding in a liquid containing sludge and a sliding rake pressing against the internal wall of the centrifuge to dislodge and move the sludge, a power drive for spinning the centrifuge at high speed and a rotating drying table to take the sludge and dry it [fr

  10. Transforming your Municipal Electric Utility

    International Nuclear Information System (INIS)

    Harper, P.

    1999-01-01

    A series of overhead viewgraphs accompanied this presentation which focused on what municipalities should and can do to prepare for a competitive energy market in Ontario. Particular attention was given to business strategies, restructuring and transformation of the Municipal Electric Utilities (MEU). Issues and questions regarding ownership were also discussed. Each municipality will have to decide what is the most appropriate governance and organizational structure for their MEU. It was noted that one of the most contentious areas is refinancing and rate structures. Issues regarding merger or partnering options were also discussed. 1 tab

  11. Sewage sludge - What can be done with it?

    International Nuclear Information System (INIS)

    Beurer, P.; Geering, F.

    2002-01-01

    This article presents a review of the state-of-the-art in the disposal of the sewage sludge that is left over after treatment of wastewater. Also, developments over the past ten years both in market structures and in legislation are discussed and future developments are reviewed. On account of legislation and political influences on the market, the thermal exploitation of sewage sludge is looked at in depth. The ecological and economic aspects of sewage sludge disposal are examined and the costs of different methods of sewage sludge treatment are compared. Various methods of disposal including dumping, composting, incineration in cement ovens, coal-fired power stations and waste incineration facilities are discussed, as is burning in special sludge incineration plant. A prognosis is made on the development of sewage sludge quantities for Germany, Switzerland and Austria over the next years

  12. Environmental sustainability of ozonating municipal waste water

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Hansen, Peter Augusto

    The EU FP6 NEPTUNE project is related to the EU Water Framework Directive and the main goal is to develop new and optimize existing waste water treatment technologies (WWTT) and sludge handling methods for municipal waste water. Besides nutrients, a special focus area is micropollutants (e....... In total more that 20 different waste water and sludge treatment technologies are to be assessed. This paper will present the preliminary LCA results from running the induced versus avoided impact approach (mainly based on existing LCIA methodology) on one of the WWTTs, i.e. ozonation....

  13. Co-digestion of municipal organic wastes with night soil and cow ...

    African Journals Online (AJOL)

    Aghomotsegin

    a very promising way to overcome the problem of waste treatment. Biogas, which is principally ... as manure, night soil, sewage sludge and municipal solid wastes. Furthermore, the solid .... It is smokeless, hygienic and more convenient to use ...

  14. Thermoradiation treatment of sewage sludge using reactor waste fission products

    International Nuclear Information System (INIS)

    Reynolds, M.C.; Hagengruber, R.L.; Zuppero, A.C.

    1974-06-01

    The hazards to public health associated with the application of municipal sewage sludge to land usage are reviewed to establish the need for disinfection of sludge prior to its distribution as a fertilizer, especially in the production of food and fodder. The use of ionizing radiation in conjunction with mild heating is shown to be an effective disinfection treatment and an economical one when reactor waste fission products are utilized. A program for researching and experimental demonstration of the process on sludges is also outlined

  15. Biomass stabilization in the anaerobic digestion of wastewater sludges

    Energy Technology Data Exchange (ETDEWEB)

    Arnaiz, C. [Universidad de Sevilla, Dept. de Ingenieria Quimica y Ambiental, Sevilla (Spain); Gutierrez, J.C. [Universidad Pablo de Olavide, Dept. de Ciencias Ambientales, Sevilla (Spain); Lebrato, J. [Universidad de Sevilla, Grupo Tratamiento de Aguas Residuales, Sevilla (Spain)

    2005-07-01

    Sludge stabilization processes include both volatile solid destruction and biomass stabilization. Traditionally, both processes have been considered together, in such a way that, when volatile solid destruction is achieved, the biomass is considered stabilized. In this study, volatile solids reduction and biomass stabilization in the anaerobic digestion of primary, secondary and mixed sludges from municipal wastewater treatment plants were researched in batch cultures by measurements of suspended solids and suspended lipid-phosphate. The estimated kinetic constants were higher in all sludge types tested for the biomass stabilization process, indicating that volatile solids destruction and biomass stabilization are not parallel processes, since the latter one is reached before the former. (Author)

  16. Sludge Reduction by Lumbriculus Variegatus in Ahvaz Wastewater Treatment Plant

    Directory of Open Access Journals (Sweden)

    Tim Hendrickx

    2012-08-01

    Full Text Available Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensivehealth hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm.The effects of changes in dissolved oxygen (DO concentration up to 3 mg/L (run 1 and up to 6 mg/L (run 2 were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. Theaverage sludge reductions were obtained as 33% (run 2 and 32% (run 1 in worm reactor,and 16% (run 1 and 12% (run 2 in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blankconditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing.

  17. Sewage sludge irradiators: Batch and continuous flow

    International Nuclear Information System (INIS)

    Lavale, D.S.; George, J.R.; Shah, M.R.; Rawat, K.P.

    1998-01-01

    The potential threat to the environment imposed by high pathogenic organism content in municipal wastewater, especially the sludge and the world-wide growing aspirations for a cleaner, salubrious environment have made it mandatory for the sewage and sludge to undergo treatment, prior to their ultimate disposal to mother nature. Incapabilities associated with the conventional wastewater treatments to mitigate the problem of microorganisms have made it necessary to look for other alternatives, radiation treatment being the most reliable, rapid and environmentally sustainable of them. To promote the use of radiation for the sludge hygienization, Department of Atomic Energy has endeavoured to set up an indigenous, Sludge Hygienization Research Irradiator (SHRI) in the city of Baroda. Designed for 18.5 PBq of 60 Co to disinfect the digested sludge, the irradiator has additional provision for treatment of effluent and raw sewage. From engineering standpoint, all the subsystems have been functioning satisfactorily since its commissioning in 1990. Prolonged studies, spanning over a period of six years, primarily focused on inactivation of microorganism revealed that 3 kGy dose of gamma radiation is adequate to make the sludge pathogen and odour-free. A dose of 1.6 kGy in raw sewage and 0.5 kGy in effluent reduced coliform counts down to the regulatory discharge limits. These observations reflect a possible cost-effective solution to the burgeoning problem of surface water pollution across the globe. In the past, sub 37 PBq 60 Co batch irradiators have been designed and commissioned successfully for the treatment of sludge. Characterized with low dose delivery rates they are well-suited for treating low volumes of sludge in batches. Some concepts of continuous flow 60 Co irradiators having larger activities, yet simple and economic in design, are presented in the paper

  18. Enhancement of activated sludge disintegration and dewaterability by Fenton process

    Science.gov (United States)

    Heng, G. C.; Isa, M. H.

    2016-06-01

    Municipal and industrial wastewater treatment plants produce large amounts of sludge. This excess sludge is an inevitable drawback inherent to the activated sludge process. In this study, the waste activated sludge was obtained from the campus wastewater treatment plant at Universiti Teknologi PETRONAS (UTP), Malaysia. Fenton pretreatment was optimized by using the response surface methodology (RSM) to study the effects of three operating conditions including the dosage of H2O2 (g H2O2/kg TS), the molar ratio of H2O2/Fe2+ and reaction time. The optimum operating variables to achieve MLVSS removal 65%, CST reduction 28%, sCOD 11000 mg/L and EPS 500 mg/L were: 1000 g H2O2/kg TS, H2O2/Fe2+ molar ratio 70 and reaction time 45 min. Fenton process was proved to be able to enhance the sludge disintegration and dewaterability.

  19. REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

    Directory of Open Access Journals (Sweden)

    Beata Janowska

    2016-12-01

    Full Text Available The sewage sludge disposal and cultivation methods consist in storage, agricultural use, compost production, biogas production or heat treatment. The sewage sludge production in municipal sewage sludge treatment plants in year 2013 in Poland amounted to 540.3 thousand Mg d.m. The sewage sludge for agricultural or natural use must satisfy chemical, sanitary and environmental safety requirements. The heavy metal content, including the mercury content, determines the sewage sludge disposal method. Mercury has a high chemical activity and biological form compounds with different properties. The properties of the mercury present in sewage sludge or composts, its potential bioavailability depend on its physicochemical forms. Different forms of mercury, which are found in soil and sediments and sewage sludge, may be determined using various techniques sequential extraction. In order to assess the bioavailability the analysis of fractional of mercury in samples of sewage sludge and composts was made. For this purpose the analytical procedure based on a four sequential extraction process was applied. Mercury fractions were classified as exchangeable (EX, base soluble (BS, acids soluble (AS and oxidizable (OX. This article presents the research results on the mercury compounds contents in sewage sludge subjected to drying process, combustion and in composted sewage sludge. During drying and combustion process of the sewage sludge, mercury transforms into volatile forms that could be emitted into the atmosphere. The mercury fractionation in composted sewage sludge proved that mercury in compost occurs mainly in an organic fraction and in a residual fraction that are scarce in the environment.

  20. CHALLENGES IN SLUDGE STABILIZATION: REGULATORY COMPLIANCE IN THE DESIGN AND OPERATION OF FACILITIES

    Science.gov (United States)

    Successful sewage sludge management involving the beneficial use of biosolids is predicated on acceptable quality of the product. Sludge quality can be defined in many ways. One of the most critical qualities affecting product marketability is sludge stability. While the terms &q...

  1. Market dynamics as a driver towards the evolution of research needs; the case of up-flow anaerobic sludge blanket seeding granules

    CSIR Research Space (South Africa)

    Musee, N

    2013-01-01

    Full Text Available Market dynamics offer positive (incentive) or negative (disincentive) feedback loops that shape the research needs for, or certain aspects of, a particular technology. Our case study results illustrate how market dynamics have influenced...

  2. Risk assessments of polybrominated diphenyl ethers (PBDEs) during sludge application in China

    Science.gov (United States)

    Qian, Jun

    2018-02-01

    Due to increasingly less space in municipal environment, waste management has become an urgent issue worldwide. As one of common municipal waste, sewage sludge from wastewater treatment plants (WWTPs) contains abundant nutrients, some of which can be quite essential for plant growth. In consideration of nutrient recycling and energy saving, sludge application has been frequently promoted in many countries across the world. However, even after several sludge stabilization procedures, sewage sludge may still contain a large variety of toxic pollutants, especially some emerging organic contaminants (EOCs). Applied in various household products and plastic industries as additives, polybrominated diphenyl ethers (PBDEs) have been constantly detected in sewage sludge samples from several cities in China since 2005, as well as some biosolid samples after sludge stabilization processes, suggesting their strong persistence and wide occurrence. During sludge application onto farmland soils, PBDEs may desorb from sludge particles and get attached by soil organic matter (SOM), followed by plant root uptake and translocation to aboveground tissues. In this study, data about current pollution of PBDEs in sewage sludge samples from China was reviewed, and the potential risks during sludge application was comprehensively assessed.

  3. Sewage Sludge Treatment for Energy Purpose in China : Waste Treatment in China

    OpenAIRE

    Nyyssönen, Ville

    2015-01-01

    This thesis is made for ANDRITZ China Technology to find out sludge incineration potential in China. ANDRITZ is looking for markets and customers for ANDRITZ sewage sludge incineration technology in China. In addition ANDRITZ China manufactures centrifuges, skeleton model filter presses, belt presses and rotatory drums to treat the sludge. Sludge in China has become a major problem. It is considered to be toxic waste, because it contains pathogens, which are dangerous for human health. Th...

  4. Co-fermentation of food-wastes and municipal sewage sludge in the wastewater treatment plant in Frick; Co-Vergaerung von Speisresten und kommunalem Klaerschlamm in der ARA Frick

    Energy Technology Data Exchange (ETDEWEB)

    Naef, B. [Verdesis Suisse SA, Aarau (Switzerland); Engeli, H. [Engeli Engineering, Neerach (Switzerland); Droessler, O. [Hochschule Waedenswil (HSW), Waedenswil (Switzerland)

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) reports on tests made at the wastewater treatment plant in Frick, Switzerland. The tests involved the addition of used frying oil to the sewage sludge in the plant's digester tanks. The increase in biogas production noted as a result is commented on. The biogas produced was used to fuel a micro-gas-turbine. Measurements made on-site provided data on the quantity and quality of the biogas produced. The authors state that, in this way, existing infrastructure can be used more effectively for the production of energy. Figures are given on the sewage plant itself and on the input and output of the system and presented in tabular and graphical form. The micro-gas-turbine used is described.

  5. N Uptake From Irradiated Sludge Combined With N Fertilizer By Edible Nightshade Crop

    International Nuclear Information System (INIS)

    Mitrosuharjo, M.M.; Haryanto; S, Suwirma; Harsojo; Hilmy N

    2000-01-01

    A greenhouse pot experiment has been carried out to study the amount of N uptake from sludge by edible nightshade (solanum melongena) crop. Sludge used in this experiment was a municipal sludge that has been processed (to be a compost sludge so it was ready to be used) from pulo gebang, east jakarta, then sludge was irradiated in a dose rate between 3.6 to 4.4 kGy at P3TIR-BATAN, jakarta. The sludge was given in the amount equivalent to 60, 120, 180 and 240 kg N/ha. For control was used treatment without sludge, without sludge but with N fertilizer in a normal rate. Each of treatment was applied with 15N in the rate equivalent to 20 kg N/ha. For buffer of soil nutrient, fertilizer P and K were also applied in normal rate. As experimental crop hybrid edible nightshade of FORTUNA variety was used. Result of this experiment showed that application of sludge was able to increase yield, dry matter production, total N uptake and N uptake derived from sludge. The amount of N uptake derived from sludge was spread between 17.5 to 151.8 mg N/pot for application sludge in 1% N content at the rate equivalent 60 to 240 kg N/ha

  6. Co-firing a pressurized fluidized-bed combustion system with coal and refuse derived fuels and/or sludges. Task 16

    Energy Technology Data Exchange (ETDEWEB)

    DeLallo, M.; Zaharchuk, R.

    1994-01-01

    The co-firing of waste materials with coal in utility scale power plants has emerged as an effective approach to produce energy and manage municipal waste. Leading this approach, the atmospheric fluidized-bed combustor (AFBC) has demonstrated its commercial acceptance in the utility market as a reliable source of power burning a variety of waste and alternative fuels. The fluidized bed, with its stability of combustion, reduces the amount of thermochemical transients and provides for easier process control. The application of pressurized fluidized-bed combustor (PFBC) technology, although relatively new, can provide significant enhancements to the efficient production of electricity while maintaining the waste management benefits of AFBC. A study was undertaken to investigate the technical and economic feasibility of co-firing a PFBC with coal and municipal and industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in central power station and distributed locations. Wastes considered for co-firing include municipal solid waste (MSW), tire-derived fuel (TDF), sewage sludge, and industrial de-inking sludge. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. This paper describes the results of this investigation, presents conclusions on the key issues, and provides recommendations for further evaluation.

  7. Toluene in sewage and sludge in wastewater treatment plants.

    Science.gov (United States)

    Mrowiec, Bozena

    2014-01-01

    Toluene is a compound that often occurs in municipal wastewater ranging from detectable levels up to 237 μg/L. Before the year 2000, the presence of the aromatic hydrocarbons was assigned only to external sources. The Enhanced Biological Nutrients Removal Processes (EBNRP) work according to many different schemes and technologies. For high-efficiency biological denitrification and dephosphatation processes, the presence of volatile fatty acids (VFAs) in sewage is required. VFAs are the main product of organic matter hydrolysis from sewage sludge. However, no attention has been given to other products of the process. It has been found that in parallel to VFA production, toluene formation occurred. The formation of toluene in municipal anaerobic sludge digestion processes was investigated. Experiments were performed on a laboratory scale using sludge from primary and secondary settling tanks of municipal treatment plants. The concentration of toluene in the digested sludge from primary settling tanks was found to be about 42,000 μg/L. The digested sludge supernatant liquor returned to the biological dephosphatation and denitrification processes for sewage enrichment can contain up to 16,500 μg/L of toluene.

  8. Marketing.

    Science.gov (United States)

    Chambers, David W

    2010-01-01

    There is not enough marketing of dentistry; but there certainly is too much selling of poor quality service that is being passed off as dentistry. The marketing concept makes the patient and the patients' needs the ultimate criteria of marketing efforts. Myths and good practices for effective marketing that will promote oral health are described under the traditional four "Ps" categories of "product" (best dental care), "place" (availability), "promotion" (advertising and other forms of making patients aware of available services and how to use them), and "price" (the total cost to patients of receiving care).

  9. Solubilisation of sludge by combined chemical and enzymatic ...

    African Journals Online (AJOL)

    In this study, the effects of cation-binding agents used alone and/or in combination with enzymes on solubilisation of municipal sludge and structure changes were investigated. Formic acid, citric acid, tartaric acid, EDTA, sodium tripolyphosphate (STPP), Zeolite A, sodium fluoride, sodium thiosulphate or sodium silicate were ...

  10. Chemical and thermal properties of VIP latrine sludge

    African Journals Online (AJOL)

    2015-07-04

    Jul 4, 2015 ... This study investigated the chemical and thermal properties of faecal sludge from 10 dry VIP latrines in Bester's Camp in the eThekwini Municipality, Durban, ... emptying and treatment equipment. A manual sorting of the pit .... (LaDePa) plant (Harrison and Wilson, 2012). Figure 3 illustrates the depths of the ...

  11. Effects of ultrasonic disintegration of excess sewage sludge.

    Science.gov (United States)

    Zielewicz, Ewa

    2016-10-01

    Breaking down sludge floc (sonodyspergation effect) and destruction of the cell membranes of microorganisms forming floc is a direct effect of ultrasonic disintegration of sludge excess. This results in release of organic material by liquid sludge (the sonolysis effect). Desired technological effects of the disintegration are: to shorten the hydrolytic phase of fermentation, to increase the production of biogas (source of renewable energy) and an increased mineralization (stability) of fermented sludge. The presented study demonstrates research covering thickened excess sludge of various physicochemical properties, collected from nine municipal sewage treatment plants. The sludge was subjected to ultrasonic disintegration using three differently constructed disintegrators and different proportions of sonification area. Direct effects of disintegration were monitored and recorded using selected indicators describing changes in the properties of sludge and increase of substance dispersed and dissolved in the supernatant liquid to be filtered. Studies have demonstrated that those (direct) effects of ultrasonic disintegration depend on the physicochemical properties of the sludge (foremost the concentration of dry solids) that determine their variable susceptibility to the disintegration methods. The direct effects also depend on optimal process conditions (which consist of the construction of the ultrasonic disintegrator), the geometric proportions of the sonication area and the operating parameters of disintegration (which could be appropriately matched to the characteristics of sludge). The most preferable results were obtained for ultrasonic disintegration of sludge with a dry matter concentration C 0 < 4.2 %. The highest effect of sonolysis-an almost 30-fold increase in the COD dissolved in the supernatant-was obtained for the sludge of lowest dry matter (C 0 = 2.0 %), which was sonicated in a reactor with a short transducer of the largest radiating surface

  12. Survey in organic contaminants content in sewage sludge from the Emilia Romagna region

    International Nuclear Information System (INIS)

    Mantovi, P.; Sassi, D.; Piccinini, S.; Rossi, L.

    2008-01-01

    Data was collected on the organic pollutants cited in the Working document on sludge, 3. draft (AOX, LAS, DEHP, NPE, PAH, PCB, PCDD/F), for sewage sludge deriving from 12 municipal-industrial wastewater treatment plants and 7 agro-industrial wastewater treatment plants located in the Emilia-Romagna region (Italy), taking samples in spring, summer and winter. The limit values given in the Working document were sporadically exceeded. The most frequent contamination was associated with LAS, in particular in the winter period. Results confirmed lower organic contaminant contents in sludge of agro-industrial origin, compared to sludge from municipal-industrial wastewater treatment plants, with generally not detectable values for the majority of organic pollutants. Comparison of the results collected in this survey with values recorded in other European countries shows that the organic contaminant content of sewage sludge obtained in plants in the Emilia-Romagna region, excepting LAS, is reasonable [it

  13. Municipal Solid Waste Management: Recycling, Resource Recovery, and Landfills. LC Science Tracer Bullet.

    Science.gov (United States)

    Meikle, Teresa, Comp.

    Municipal solid waste refers to waste materials generated by residential, commercial, and institutional sources, and consists predominantly of paper, glass, metals, plastics, and food and yard waste. Within the definition of the Solid Waste Disposal Act, municipal solid waste does not include sewage sludge or hazardous waste. The three main…

  14. PRESENCE OF HELMINTH EGGS IN SEWAGE SLUDGE FROM CAMPO GRANDE (MS, BRAZIL MUNICIPALITY AFTER ANAEROBIC TREATMENT LEVANTAMENTO DE OVOS DE HELMINTOS EM LODO DE ESGOTO ORIUNDO DE CAMPO GRANDE (MS APÓS TRATAMENTO ANAERÓBICO

    Directory of Open Access Journals (Sweden)

    Juliana Rosa Carrijo

    2008-04-01

    Full Text Available The present study was conducted to evaluate the helminth eggs presence in sewage sludge, previously treated in anerobic digestion process like anaerobic liquid fluid reactor. First of all were evaluated different kinds of materials to choose the best filter which permitted to filter the Taenia saginata eggs. The filter that showed better adaptation was the fine toilet paper one sheet. The helminth eggs were classified for their genera, according to their morphology. The Taenia sp, Trichuris, Dipylidium and Strongyloides were find only in one collect. The number of nematode eggs prevailed on the cestodes. The quantity of helminths eggs found was variable, indicatting complementary treatments process to the sewage sludge. It was concluded that the filter tested was efficient to Taenia sp eggs and to other helminth eggs present in sewage sludge. KEY WORDS: Biossolid, filter, Taenia sp. O presente trabalho avaliou a presença de ovos de helmintos em lodo de esgoto, previamente tratado em sistema de digestão anaeróbia do tipo reator anaeróbio de lodo fluidizado (RALF. Primeiramente testaram-se diferentes tipos de materiais para a escolha do filtro que possibilitasse a passagem de ovos de Taenia saginata. O filtro mais adequado foi o papel higiênico fino, folha única. Classificaram-se os ovos de helmintos por gênero, de acordo com sua morfologia. Encontraram-se ovos de Taenia sp, Trichuris, Dipylidium e

  15. Co-disposal of sewage sludge and solid wastes-it works

    Energy Technology Data Exchange (ETDEWEB)

    Sussman, D B

    1977-10-01

    The problem of sludge disposal is one of more sludge than ever before, few suitable land disposal or land application sites, the ocean dumping option being phased out, and energy cost so high or supplies so few as to make incineration a questionable endeavor. The energy required to run a wastewater treatment plant and the heat needed to incinerate the sludge may be available in the same community in the form of municipal solid waste. Municipal sludge has a heat value of about 10,000 Btu/lb of dry solids; it is autogenous at>30% solids. Codisposal techniques are discussed which use the energy produced by the combustion of solid waste to dewater the sludge to its autogenous point. One approach is to use sewage sludge incinerators, in many cases already installed at the wastewater treatment plant, and to use the organic portion of solid waste as a fuel to dry, burn, and reduce the volume of the sludge that must ultimately be disposed. A second approach would use a solid waste incinerator, solid waste-fired steam generator, or waterwall combustion unit to burn dewatered sludge. Both approaches are being demonstrated or used. Thermal sludge disposal at wastewater treatment plants normally is carried out in multiple-hearth or fluidized-bed incinerators. The experiences of such plants in the US and Europe are summarized.

  16. Energy and Resource Recovery from Sludge. State of Science Report

    Energy Technology Data Exchange (ETDEWEB)

    Kalogo, Y; Monteith, H [Hydromantis Inc., Hamilton, ON (Canada)

    2008-07-01

    There is general consensus among sanitary engineering professionals that municipal wastewater and wastewater sludge is not a 'waste', but a potential source of valuable resources. The subject is a major interest to the members of the Global Water Research Coalition (GWRC). The GWRC is therefore preparing a strategic research plan related to energy and resource recovery from wastewater sludge. The initial focus of the strategy will be on sewage sludge as water reuse aspects have been part of earlier studies. The plan will define new research orientations for deeper investigation. The current state of science (SoS) Report was prepared as the preliminary phase of GWRC's future strategic research plan on energy and resource recovery from sludge.

  17. Sewage sludge disinfection by irradiation (ENEA-ACEA collaboration)

    International Nuclear Information System (INIS)

    Baraldi, D.

    1997-01-01

    The Municipal Association for Electricity and Water (ACEA) of Rome and the Lazio Regional Administration are implementing a programme of intervention aimed at protecting the water quality of the hydrogeological basin of Lake Bracciano. With support from ENEA, a pilot plant is being constructed for sewage-sludge direction by irradiation with accelerated electrons, in order to use the sludge as a fertilizer for agriculture, as is practised abroad mainly in Germany and the United States. The work to be carried out within the ENEA-ACEA agreement includes: sludge digestion, drying, and sterilization by irradiation. Results achieved so far, including preliminary analyses of irradiated sludge, are presented. The irradiation plant and processes involved are also described. (author)

  18. Energy and Resource Recovery from Sludge. State of Science Report

    Energy Technology Data Exchange (ETDEWEB)

    Kalogo, Y.; Monteith, H. [Hydromantis Inc., Hamilton, ON (Canada)

    2008-07-01

    There is general consensus among sanitary engineering professionals that municipal wastewater and wastewater sludge is not a 'waste', but a potential source of valuable resources. The subject is a major interest to the members of the Global Water Research Coalition (GWRC). The GWRC is therefore preparing a strategic research plan related to energy and resource recovery from wastewater sludge. The initial focus of the strategy will be on sewage sludge as water reuse aspects have been part of earlier studies. The plan will define new research orientations for deeper investigation. The current state of science (SoS) Report was prepared as the preliminary phase of GWRC's future strategic research plan on energy and resource recovery from sludge.

  19. Sludge dewatering in a decanter centrifuge aided by cationic flocculant Praestol 855BS and essential oil of waste orange peels

    Directory of Open Access Journals (Sweden)

    Kowalczyk Anna

    2016-03-01

    Full Text Available In the study the comparative analysis of test results of drainage of municipal wastewater sludge was conducted with the use of flocculant Praestol 855BS and the mixture of flocculant Praestol 855BS 50% + orange essential oil 50%, as the reagents supporting this process. It was also attempted to reduce unpleasant smells exuding from the drained sludge.

  20. The presence of contaminations in sewage sludge - The current situation.

    Science.gov (United States)

    Fijalkowski, Krzysztof; Rorat, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata J

    2017-12-01

    Sewage sludge/biosolids are by-wastes of municipal and industrial wastewater treatment. As sources of nutrients (C, N, P) they are widely used in intensive farming where large supplementation of organic matter to maintain fertility and enhance crop yields is needed. However, according to the report of European Commission published in 2010, only 39% of produced sewage sludge is recycled into agriculture in the European Union. This situation occurs mainly due to the fact, that the sewage sludge may contain a dangerous volume of different contaminants. For over decades, a great deal of attention has been focused on total concentration of few heavy metals and pathogenic bacteria Salmonella and Escherichia coli. The Sewage Sludge Directive (86/278/EEC) regulates the allowable limits of Zn, Cu, Ni, Pb, Cd, Cr and Hg and pathogens and allows for recovery of sludge on land under defined sanitary and environmentally sound conditions. In this paper, a review on quality of sewage sludge based on the publications after 2010 has been presented. Nowadays there are several papers focusing on new serious threats to human health and ecosystem occurring in sewage sludge - both chemicals (such as toxic trace elements - Se, Ag, Ti; nanoparticles; polyaromatic hydrocarbons; polychlorinated biphenyl; perfluorinated surfactants, polycyclic musks, siloxanes, pesticides, phenols, sweeteners, personal care products, pharmaceuticals, benzotriazoles) and biological traits (Legionella, Yersinia, Escherichia coli O157:H7). Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Co-digestion of pig slaughterhouse waste with sewage sludge.

    Science.gov (United States)

    Borowski, Sebastian; Kubacki, Przemysław

    2015-06-01

    Slaughterhouse wastes (SHW) are potentially very attractive substrates for biogas production. However, mono-digestion of these wastes creates great technological problems associated with the inhibitory effects of ammonia and fatty acids on methanogens as well as with the foaming in the digesters. In the following study, the co-digestion of slaughterhouse wastes with sewage sludge (SS) was undertaken. Batch and semi-continuous experiments were performed at 35°C with municipal sewage sludge and pig SHW composed of meat tissue, intestines, bristles and post-flotation sludge. In batch assays, meat tissue and intestinal wastes gave the highest methane productions of 976 and 826 dm(3)/kg VS, respectively, whereas the methane yield from the sludge was only 370 dm(3)/kg VS. The co-digestion of sewage sludge with 50% SHW (weight basis) provided the methane yield exceeding 600 dm(3)/kg VS, which was more than twice as high as the methane production from sewage sludge alone. However, when the loading rate exceeded 4 kg VS/m(3) d, a slight inhibition of methanogenesis was observed, without affecting the digester stability. The experiments showed that the co-digestion of sewage sludge with large amount of slaughterhouse wastes is feasible, and the enhanced methane production does not affect the digester stability. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Predicting the degradability of waste activated sludge.

    Science.gov (United States)

    Jones, Richard; Parker, Wayne; Zhu, Henry; Houweling, Dwight; Murthy, Sudhir

    2009-08-01

    The objective of this study was to identify methods for estimating anaerobic digestibility of waste activated sludge (WAS). The WAS streams were generated in three sequencing batch reactors (SBRs) treating municipal wastewater. The wastewater and WAS properties were initially determined through simulation of SBR operation with BioWin (EnviroSim Associates Ltd., Flamborough, Ontario, Canada). Samples of WAS from the SBRs were subsequently characterized through respirometry and batch anaerobic digestion. Respirometry was an effective tool for characterizing the active fraction of WAS and could be a suitable technique for determining sludge composition for input to anaerobic models. Anaerobic digestion of the WAS revealed decreasing methane production and lower chemical oxygen demand removals as the SRT of the sludge increased. BioWin was capable of accurately describing the digestion of the WAS samples for typical digester SRTs. For extended digestion times (i.e., greater than 30 days), some degradation of the endogenous decay products was assumed to achieve accurate simulations for all sludge SRTs.

  3. Liberalisation of municipal waste handling

    DEFF Research Database (Denmark)

    Busck, Ole Gunni

    2006-01-01

    for improved performance of municipal waste management. The study stresses the need for training and guidance of municipal administrators. Highlighting ‘best practice’ examples the study shows, however, that it is perfectly possible to end up with quality service on contract. It takes a mixture of careful...... of price reductions in stead of quality demands in both environmental and working environmental terms. A recent study showed major deficits in the capacities of the municipalities to administer qualitative requirements in the tender process and to manage the contracts as an integral part of a scheme...... forces and low quality performance. By assuming responsibility, setting and following up on high quality standards the tender instrument presents an additional instrument to legislation and market based means to institutionalize more sustainable practices in waste management...

  4. Sludge recovery apparatus

    International Nuclear Information System (INIS)

    Marmo, A.R.

    1979-01-01

    An improved design of a sludge recovery apparatus used in the fabrication of nuclear fuel is described. This apparatus provides for automatic separation of sludge from the grinder coolant, drying of the sludge into a flowable powder and transfer of the dry powder to a salvage container. It can be constructed to comply with criticality-safe-geometry requirements and to obviate need for operating personnel in its immediate vicinity. (UK)

  5. Pilot plant experience on anaerobic codigestion of source selected OFMSW and sewage sludge.

    Science.gov (United States)

    Cabbai, Valentina; De Bortoli, Nicola; Goi, Daniele

    2016-03-01

    Anaerobic codigestion of source selected organic fraction of municipal solid waste (SS-OFMSW) and sewage sludge may be one of the most viable solutions to optimize oversized digesters efficiency in wastewater treatment plants. Based on results of BMP tests obtained for sewage sludge and SS-OFMSW, pilot plant tests were carried out by 3.4 m(3) CSTR reactor at mesophilic temperature. A mix of fruit and vegetable waste from wholesale market and canteen waste was used as SS-OFMSW substrate. Tests were conducted applying an OLR (organic loading rate) ramp with 6 different phases until a value of 3.2 kgVS/m(3) d. Feedstock and digestate characteristics, efficiency and process parameters were monitored. The anaerobic codigestion development was stable in each phase: early indicators like VFA (volatile fatty acids) and FOS/TAC ratio were always below instability threshold values. The maximum OLR tested determined a GPR (gas production rate) of 0.95 N m(3)/m(3) d and SGP (specific gas production) of 0.49 N m(3)/kgVS with a VS abatement of 67.3%. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Electron beam treatment of wastewaters and sludges

    International Nuclear Information System (INIS)

    Osborn, D.W.

    1980-01-01

    Various procedures for decreasing the health risks associated with the disposal of sewage sludges are discussed including land storage, thermophilic digestion, autothermal aerobic digestion, the Porteus Process, the Zimpro Process, incineration, pyrolysis, thermal pasteurisation, composting, lime utilisation, flash drying and radiation techniques. A fully automated sludge irradiation facility at Geiselbullach near Munich and an electron accelerator experimental plant near Boston are described. Advantages and disadvantages are given for both processes. Costs of electron radiation treatment of sewage sludges (a slurry containing 5 per cent solids) for a city the size of Johannesburg is estimated to be in the order of R900 000 per year at a dose rate of 4 000 Gy, which would produce a product of reasonable hygienic quality but not necessarily meet the criteria laid down by local authority medical officers at all times. In order to reduce costs it would be necessary to have a readily available market to dispose of disinfected material

  7. Electron beam treatment of wastewaters and sludges

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, D W [City Health Dept., Johannesburg (South Africa)

    1980-12-01

    Various procedures for decreasing the health risks associated with the disposal of sewage sludges are discussed including land storage, thermophilic digestion, autothermal aerobic digestion, the Porteus Process, the Zimpro Process, incineration, pyrolysis, thermal pasteurisation, composting, lime utilisation, flash drying and radiation techniques. A fully automated sludge irradiation facility at Geiselbullach near Munich and an electron accelerator experimental plant near Boston are described. Advantages and disadvantages are given for both processes. Costs of electron radiation treatment of sewage sludges (a slurry containing 5 per cent solids) for a city the size of Johannesburg is estimated to be in the order of R900,000 per year at a dose rate of 4,000 Gy, which would produce a product of reasonable hygienic quality but not necessarily meet the criteria laid down by local authority medical officers at all times. In order to reduce costs it would be necessary to have a readily available market to dispose of disinfected material.

  8. Behavior of Ag nanoparticles in soil: Effects of particle surface coating, aging and sewage sludge amendment

    International Nuclear Information System (INIS)

    Whitley, Annie R.; Levard, Clément; Oostveen, Emily; Bertsch, Paul M.; Matocha, Chris J.; Kammer, Frank von der; Unrine, Jason M.

    2013-01-01

    This study addressed the relative importance of particle coating, sewage sludge amendment, and aging on aggregation and dissolution of manufactured Ag nanoparticles (Ag MNPs) in soil pore water. Ag MNPs with citrate (CIT) or polyvinylpyrrolidone (PVP) coatings were incubated with soil or municipal sewage sludge which was then amended to soil (1% or 3% sludge (w/w)). Pore waters were extracted after 1 week and 2 and 6 months and analyzed for chemical speciation, aggregation state and dissolution. Ag MNP coating had profound effects on aggregation state and partitioning to pore water in the absence of sewage sludge, but pre-incubation with sewage sludge negated these effects. This suggests that Ag MNP coating does not need to be taken into account to understand fate of AgMNPs applied to soil through biosolids amendment. Aging of soil also had profound effects that depended on Ag MNP coating and sludge amendment. -- Highlights: •Silver nanoparticle coating affects fate in unamended soils. •Citrated coated silver nanoparticles could be found in pore water for up to six months. •Pre-incubation of silver nanoparticles in sewage sludge negated effects of surface coating. •Weathered or reprecipitated particles found in pore water for up to two months in sludge amended soils. •Particle surface coating, sewage sludge amendment and aging all have important impacts. -- Behavior of manufactured silver nanoparticles in soil depends on surface coating, contact with sewage sludge, and aging

  9. Unified Modeling of Filtration and Expression of Biological Sludge

    DEFF Research Database (Denmark)

    Sørensen, Peter Borgen

    Dewatering is a costly operation in both industry, e.g . when dewatering drilling mud, harbor sludge or biomass, and at municipal wastewater treatment plants when dewatering biological sludges. In practice, design and operation of dewatering equipment are mostly based on empirical knowledge, and ......, and normally results are not satisfactory, e.g. in terms of cake solids or capacity of equipment. Thus, there is a need for theoretical and technical developments to improve dewatering performance, based on better scientific knowledge and well defined principles and rules....

  10. Applicability and trends of anaerobic granular sludge treatment processes

    International Nuclear Information System (INIS)

    Lim, Seung Joo; Kim, Tak-Hyun

    2014-01-01

    Anaerobic granular sludge treatment processes have been continuously developed, although the anaerobic sludge granulation process was not clearly understood. In this review, an upflow anaerobic sludge blanket (UASB), an expanded granule sludge blanket (EGSB), and a static granular bed reactor (SGBR) were introduced as components of a representative anaerobic granular sludge treatment processes. The characteristics and application trends of each reactor were presented. The UASB reactor was developed in the late 1970s and its use has been rapidly widespread due to the excellent performance. With the active granules, this reactor is able to treat various high-strength wastewaters as well as municipal wastewater. Most soluble industrial wastewaters can be efficiently applied using a UASB. The EGSB reactor was developed owing to give more chance to contact between wastewater and the granules. Dispersed sludge is separated from mature granules using the rapid upward velocity in this reactor. The EGSB reactor shows the excellent performance in treating low-strength and/or high-strength wastewater, especially under low temperatures. The SGBR, developed at Iowa State University, is one of anaerobic granular sludge treatment processes. Although the configuration of the SGBR is very simple, the performance of this system is similar to that of the UASB or EGSB reactor. The anaerobic sludge granulation processes showed excellent performance for various wastewaters at a broad range of organic loading rate in lab-, pilot-scale tests. This leads to erect thousands of full-scale granular processes, which has been widely operated around the world. -- Highlights: • Anaerobic sludge granulation is a key parameter for maintaining granular processes. • Anaerobic granular digestion processes are applicable for various wastewaters. • The UASB is an economic high-rate anaerobic granular process. • The EGSB can treat high-strength wastewater using expanding granules. • The SGBR is

  11. Low intensity surplus activated sludge pretreatment before anaerobic digestion

    Directory of Open Access Journals (Sweden)

    Suschka Jan

    2017-12-01

    Full Text Available Sewage sludge (municipal, or industrial treatment is still a problem in so far that it is not satisfactorily resolved in terms of cost and final disposal. Two common forms of sludge disposal are possible; the first being direct disposal on land (including agriculture and the second being incineration (ash production, although neither of these methods are universally applied. Simplifying the issue, direct sludge disposal on land is seldom applied for sanitary and environmental reasons, while incineration is not popular for financial (high costs reasons. Very often medium and large wastewater treatment plants apply anaerobic digestion for sludge hygiene principles, reducing the amount to be disposed and for biogas (energy production. With the progress in sewage biological treatment aiming at nutrient removal, primary sludge has been omitted in the working processes and only surplus activated sludge requires handling. Anaerobic digestion of waste activated sludge (WAS is more difficult due to the presence of microorganisms, the decomposition of which requires a relatively long time for hydrolysis. In order to upgrade the hydrolysis effects, several different pre-treatment processes have already been developed and introduced. The additional pre-treatment processes applied are aimed at residual sludge bulk mass minimization, shortening of the anaerobic digestion process or higher biogas production, and therefore require additional energy. The water-energy-waste Nexus (treads of of the benefits and operational difficulties, including energy costs are discussed in this paper. The intensity of pre-treatment processes to upgrade the microorganism’s hydrolysis has crucial implications. Here a low intensity pre-treatment process, alkalisation and hydrodynamic disintegration - hybrid process - were presented in order to achieve sufficient effects of WAS anaerobic digestion. A sludge digestion efficiency increase expressed as 45% biogas additional

  12. K basins sludge removal sludge pretreatment system

    International Nuclear Information System (INIS)

    Chang, H.L.

    1997-01-01

    The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

  13. Respirometry in activated sludge

    NARCIS (Netherlands)

    Spanjers, H.

    1993-01-01

    The purpose of the study was (1) to develop a respiration meter capable of continuously measuring, using different procedures, the oxygen uptake rate of activated sludge and (2) to expand knowledge about respiration related characteristics of wastewater and activated sludge.

    A

  14. Carbon-14 in sludge

    International Nuclear Information System (INIS)

    Fowler, J.R.; Coleman, C.J.

    1983-01-01

    The level of C-14 in high-level waste is needed to establish the amount of C-14 that will be released to the environment either as off-gas from the Defense Waste Processing Facility (DWPF) or as a component of saltstone. Available experimental data confirmed a low level of C-14 in soluble waste, but no data was available for sludge. Based on the processes used in each area, Purex LAW sludge in F-area and HM HAW sludge in H-area will contain the bulk of any sludge produced by the cladding. Accordingly, samples from Tank 8F containing Purex LAW and Tank 15H containing HM HAW were obtained and analyzed for C-14. These two waste types constitute approximately 70% of the total sludge inventory now stored in the waste tanks. Results from analyses of these two sludge types show: the total C-14 inventory in sludge now stored in the waste tanks is 6.8 Ci; C-14 releases to the atmosphere from the DWPF will average approximately 0.6 Ci annually at the projected sludge processing rate in the DWPF. 4 references, 2 tables

  15. Environmentally compatible sewage sludge disposal; Umweltgerechte Klaerschlammentsorgung

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J. [Technische Univ. Braunschweig (Germany). Inst. fuer Mechanische Verfahrenstechnik; Schwedes, J. [Technische Univ. Braunschweig (Germany). Inst. fuer Mechanische Verfahrenstechnik

    1997-09-01

    Cleaning of municipal and industrial waste water is done by means of biological processes: micro-organisms degrade pollutants. The resulting products are, besides cleaned waste water, sewage sludge and surplus sludge. Their disposal involves ecological and economic problems. One approach to their partial disposal is their degradation in a digester. Approximately one half of the organic substance is converted by anaerobic bacteria into energy-rich biogas. Optimization of this digestion process accelerates the anaerobic degradation process, increases the accruing amount of digester gas and reduces the volume of digested sludge to be disposed of. With these objectives, the Institute fuer Mechanische Verfahrenstechnik is conducting research into the mechanical treatment of micro-organisms remaining in surplus sludge by means of different treatment devices. The project is sponsored under the programme of the Deutsche Forschungsgemeinschaft DFG ``Biological processes with dispersive solids``. Mechanical treatment renders the cell constituents exploitable to anaerobic bacteria; the resulting sludge degradation is more rapid and more complete. (orig./ABI) [Deutsch] Zur Reinigung haeuslicher und industrieller Abwaesser werden biologische Prozesse eingesetzt. Dabei sorgen Mikroorganismen fuer den Abbau der Verunreinigungen. Neben dem gereinigten Abwasser fallen Primaer- und Ueberschussschlamm an, deren Entsorgung oekologische und oekonomische Probleme verursacht. Ein Weg zur partiellen Beseitigung dieser Klaerschlaemme ist ihr Abbau in einem Faulbehaelter. Dabei wird etwa die Haelfe der organischen Substanz durch anaerobe Bakterien zu einem energiereichen Biogas umgewandelt. Eine Optimierung dieses Faulprozesses beinhaltet: 1. Beschleunigung des anaeroben Abbauprozesses, 2. Erhoehung der anfallenden Faulgasmenge und 3. Reduzierung der zu entsorgenden Faulschlammenge. Mit diesen Zielsetzungen wird am Institut fuer Mechanische Verfahrenstechnik im Rahmen der DFG

  16. Sustainable treatment of municipal waste water

    DEFF Research Database (Denmark)

    Hansen, Peter Augusto; Larsen, Henrik Fred

    The main goal of the EU FP6 NEPTUNE program is to develop new and improve existing waste water treatment technologies (WWTT) and sludge handling technologies for municipal waste water, in accordance with the concepts behind the EU Water Framework Directive. As part of this work, the project.......e. heavy metals, pharmaceuticals and endocrine disruptors) in the waste water. As a novel approach, the potential ecotoxicity and human toxicity impacts from a high number of micropollutants and the potential impacts from pathogens will be included. In total, more that 20 different waste water and sludge...... treatment technologies are to be assessed. This paper will present the first LCA results from running existing life cycle impact assessment (LCIA) methodology on some of the waste water treatment technologies. Keywords: Sustainability, LCA, micropollutants, waste water treatment technologies....

  17. Epidemiological risks of endoparasitoses spread by municipal waste water

    Directory of Open Access Journals (Sweden)

    Dudlová A.

    2015-09-01

    Full Text Available The occurrence of developmental stages of endoparasite germs (cysts, oocysts, protozoa, and helminth eggs as an indirect detection factor of endoparasitoses circulation in the environment, was examined in raw municipal wastewater, sludge and biologically cleaned waste water. Examination of municipal wastewater and sludge from five monitored wastewater treatment plants (WWTPs in east Slovakia, from various fractions of municipal wastewater, confirmed 35.87 % positivity of samples for the endoparasitic germs. Among of all analysed samples 11.09 % were protozoan oo(cysts and 20.87 % were helminth eggs. 3.91 % of samples showed positivity to both the helminth eggs and protozoan oo(cysts. In the raw wastewater the protozoa comprised of Giardia spp. (1.08 % and Entamoeba spp. (1.08 %. The helminth eggs primarily consisted of Ascaris spp. (4.35 % and strongyle-type eggs (3.26 %. No germs of protozoa or helminths were found in the treated wastewater. However, the highest presence of the germs was found in drained stabilised sludge. The average number of oo(cysts/kg was 2.86±0.24 and the average number of helminth eggs/kg was 5.77±0.09. In all kinds of sludge, obtained during the process of wastewater treatment, there were protozoan (Giardia spp., Cryptosporidium spp., Entamoeba spp. and helminths eggs (Ascaris spp., Trichuris spp., Taenia spp., Hymenolepis spp., or strongyle-type eggs presented. In drained (condensed stabilised sludge the eggs of Capillaria spp. and Toxocara spp. were also detected. From the epidemiological aspect the sewage sludge, due to high concentration of protozoal oo(cysts or helminth eggs, represents a significant epidemiological risk for the endoparasitoses dissemination.

  18. Moisture distribution in sludges based on different testing methods

    Institute of Scientific and Technical Information of China (English)

    Wenyi Deng; Xiaodong Li; Jianhua Yan; Fei Wang; Yong Chi; Kefa Cen

    2011-01-01

    Moisture distributions in municipal sewage sludge, printing and dyeing sludge and paper mill sludge were experimentally studied based on four different methods, i.e., drying test, thermogravimetric-differential thermal analysis (TG-DTA) test, thermogravimetricdifferential scanning calorimetry (TG-DSC) test and water activity test. The results indicated that the moistures in the mechanically dewatered sludges were interstitial water, surface water and bound water. The interstitial water accounted for more than 50% wet basis (wb) of the total moisture content. The bond strength of sludge moisture increased with decreasing moisture content, especially when the moisture content was lower than 50% wb. Furthermore, the comparison among the four different testing methods was presented.The drying test was advantaged by its ability to quantify free water, interstitial water, surface water and bound water; while TG-DSC test, TG-DTA test and water activity test were capable of determining the bond strength of moisture in sludge. It was found that the results from TG-DSC and TG-DTA test are more persuasive than water activity test.

  19. Sludge storage lagoon biogas recovery and use. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Muller, D.; Norville, C. [Memphis and Shelby County Div. of Planning and Development, TN (United States)

    1991-07-01

    The City of Memphis has two wastewater treatment plants. The SWTP employs two large anaerobic digestion sludge lagoons as part of the overall sludge treatment system. Although these lagoons are effective in concentrating and digesting sludge, they can generate offensive odors. The SWTP uses aerobic digesters to partially stabilize the sludge and help reduce objectionable odors before it enters the lagoons. The anaerobic digestion of sludge in the lagoons results in the dispersion of a large quantity of biogas into the atmosphere. The City realized that if the lagoons could be covered, the odor problem could be resolved, and at the same, time, biogas could be recovered and utilized as a source of energy. In 1987, the City commissioned ADI International to conduct a feasibility study to evaluate alternative methods of covering the lagoons and recovering and utilizing the biogas. The study recommended that the project be developed in two phases: (1) recovery of the biogas and (2) utilization of the biogas. Phase 1 consists of covering the two lagoons with an insulated membrane to control odor and temperature and collect the biogas. Phase 1 was found to be economically feasible and offered a unique opportunity for the City to save substantial operating costs at the treatment facility. The Memphis biogas recovery project is the only application in the world where a membrane cover has been used on a municipal wastewater sludge lagoon. It is also the largest lagoon cover system in the world.

  20. Biological treatment of sludge digester liquids.

    Science.gov (United States)

    van Loosdrecht, M C M; Salem, S

    2006-01-01

    Nitrogen removal in side stream processes offers a good potential for upgrading wastewater treatment plants (WWTPs) that need to meet stricter effluent standards. Removing nutrients from these internal process flows significantly reduces the N-load to the main treatment plant. These internal flows mainly result from the sludge processing and have a high temperature and a high concentration of ammonia. Therefore, the required reactor volumes as well as the required aerobic SRT are small. Generally, biological treatment processes are more economical and preferred over physical-chemical processes. Recently, several biological treatment processes have been introduced for sludge water treatment. These processes are available now on the activated sludge market (e.g. SHARON, ANAMMOX and BABE processes). The technologies differ in concept and in the limitations guiding the application of these processes for upgrading WWTPs. This paper reviews and compares different biological alternatives for nitrogen removal in side streams. The limitations for selecting a technology from the available ones in the activated sludge market are noted and analysed. It is stressed that the choice for a certain process is based on more aspects than pure process engineering arguments.

  1. Activated sludge model No. 3

    DEFF Research Database (Denmark)

    Gujer, W.; Henze, M.; Mino, T.

    1999-01-01

    The Activated Sludge Model No. 3 (ASM3) can predict oxygen consumption, sludge production, nitrification and denitrification of activated sludge systems. It relates to the Activated Sludge Model No. 1 (ASM1) and corrects for some defects of ASM I. In addition to ASM1, ASM3 includes storage of org...

  2. Sludge minimization technologies - an overview

    Energy Technology Data Exchange (ETDEWEB)

    Oedegaard, Hallvard

    2003-07-01

    The management of wastewater sludge from wastewater treatment plants represents one of the major challenges in wastewater treatment today. The cost of the sludge treatment amounts to more that the cost of the liquid in many cases. Therefore the focus on and interest in sludge minimization is steadily increasing. In the paper an overview is given for sludge minimization (sludge mass reduction) options. It is demonstrated that sludge minimization may be a result of reduced production of sludge and/or disintegration processes that may take place both in the wastewater treatment stage and in the sludge stage. Various sludge disintegration technologies for sludge minimization are discussed, including mechanical methods (focusing on stirred ball-mill, high-pressure homogenizer, ultrasonic disintegrator), chemical methods (focusing on the use of ozone), physical methods (focusing on thermal and thermal/chemical hydrolysis) and biological methods (focusing on enzymatic processes). (author)

  3. Municipal Bonds in Developing Countries. Case Study: Municipality of Stip, Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Marija GOGOVA SAMONIKOV

    2017-06-01

    Full Text Available The developing countries, especially in the Balkans, barely use the municipal bonds as an alternative way of financing their activities. This paper is part of the project “The municipal bonds as an alternative source of financing municipals activities and the effective management of funds, with a special emphasis to the Municipality of Stip, R. Macedonia”. The paper has an important impact, according to both academic and practical perspective. It combines the experts’ academic analysis with the municipals potential in order to facilitate a successful municipal bond emission that would support the local economic growth. The purpose of this paper is to investigate the ability and willingness of the Municipality of Stip to issue municipal bonds. The main hypothesis states that the Municipality of Stip is able to issue a municipal bond as an alternative way of financing its investment activities. The research includes the classical SWOT analysis regarding the Municipality of Stip and continues with a statistical analysis based on correlation and regression relationships within the accounts of the Municipality’s annual reports. The methodological framework is based on quantitative research methods (correlations and regression methods which result in acceptance of the main hypothesis in the paper - the municipal bonds as an alternative source for funding municipal’s activities are justified, especially if the funds are associated with a specific revenue-generating project. The findings would serve as a basis for the municipal bonds prospect, which would be the ultimate goal of combining the academic knowledge with the practical potential of the Municipality of Stip. The conclusions reveal that this would be the first municipal bond emission in the Republic of Macedonia. However, this fact can serve as an advantage in the market in terms of introducing financial instrument innovation. This paper suggests that the usage of municipal bonds is

  4. Composting plant of vegetables wastes and sewage sludges in Castesdefells. Plant de compostaje de restos de poda y lodos de depuradora en Castelldefells

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    Castelldefells Municipality (Catalonia, Spain) has set up a recycling plant for vegetable wastes mixed with sewage sludge to obtain compost. The plant treats 48.000 m''3/y. of vegetable wastes, and receive 8.000 m''3/y. of sewage sludge. (Author)

  5. Beneficial reuse of precast concrete industry sludge to produce alkaline stabilized biosolids.

    Science.gov (United States)

    Gowda, C; Seth, R; Biswas, N

    2008-01-01

    The precast concrete industry generates waste called concrete sludge during routine mixer tank washing. It is highly alkaline and hazardous, and typically disposed of by landfilling. This study examined the stabilization of municipal sewage sludge using concrete sludge as an alkaline agent. Sewage sludge was amended with 10 to 40% of concrete sludge by wet weight, and 10 and 20% of lime by dry weight of the sludge mix. Mixes containing 30 and 40% of concrete sludge with 20% lime fulfilled the primary requirements of Category 1 and 2 (Canada) biosolids of maintaining a pH of 12 for at least 72 hours. The heavy metals were below Category 1 regulatory limits. The 40% concrete sludge mix was incubated at 52 degrees C for 12 of the 72 hours to achieve the Category 1 and 2 regulations of less than 1000 fecal coliform/g solids. The nutrient content of the biosolids was 8.2, 10 and 0.6 g/kg of nitrogen, phosphorus and potassium respectively. It can be used as a top soil or augmented with potassium for use as fertilizer. The study demonstrates that concrete sludge waste can be beneficially reused to produce biosolids, providing a long-term sustainable waste management solution for the concrete industry.

  6. Costs and economic efficiency of the drying of sewage sludges; Kosten und Wirtschaftlichkeit der Klaerschlammtrocknung

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Ulrich [Haarslev Industries A/S, Herlev (Denmark). Marketing and Business Development

    2013-03-01

    New methods of the thermal utilization have to be created due to the fact that agricultural utilisation of sewage sludge and the use in the reclamation due to stringent limit values and enhanced quality criteria are available restricted in future. The incineration of mechanically dewatered and dried sewage sludge is performed in mono-combustion plants as well as in coal-fired power plants. The author of the contribution under consideration reports on the costs and economic efficiency of the drying of sewage sludge. The drying of sewage sludge may perform an important and reasonable contribution to the utilization of municipal sewage sludge. The selection of a suitable drying process should ever depend on the local realities. Proved and suitable technologies are available for every application. Before the decision for a certain provider, one should examine reference plants and consider specific experiences of the operator among the decision-making.

  7. Thermal treatment of sewage sludge from waste water. Tratamiento termico de lodos procedentes de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Andreottola, G. (Universidad de Trento (Italy)); Canziani, R.; Ragazzi, M. (Politicnico de Milan (Italy))

    1994-01-01

    Thermal Treatment of sewage sludge can be beneficial as a pre-treatment step of many treatment/disposal options, but above all, it allows the recovery of the energetic content sludge. Energy recovery from sewage sludge can be performed in many ways; direct incineration thermal drying followed by incineration and co-combustion with municipal solid wastes or other non conventional fuels. Another option is the recovery of waste energy (e.g. from an endo thermal engine using biogas as fuel) to dry sludge wich, in turn can be used as a fuel. The paper will evaluate several options of thermal treatment of sewage sludge, with particular emphasis on the energetic yield from different processes. (Author)

  8. Dewatering of sludges

    International Nuclear Information System (INIS)

    Bode, P.

    1984-01-01

    A filter rig has been designed and built. Simulated magnox and alumino ferric hydroxide sludges have been successfully filtered on this equipment and both types of sludge produced a clear filtrate and a cake. The flow rates were low. The cake often partially remained adhered to the filter membrane instead of dropping clear during the filter cleaning cycle. This filtration technique can only be used on sludges which form a non-binding cake. Permeability of the membrane can be altered by stretching. Irradiation of the membrane showed that it should withstand 20 to 50 M.rads. (author)

  9. Effect of activated sludge culture conditions on Waxberry wastewater

    Science.gov (United States)

    Shi, Liang; He, Lingfeng; Zhang, Yongli

    2018-03-01

    Treated activated sludge is suitable for the treatment of wastewater. Biochemical method is used to treat the wastewater, and the influence of time on the COD index is investigated. The results showed that time had a significant effect on COD, and then affected the performance of activated sludge. Under different time, according to the order of time from short to long, COD decreases in turn. Under the action of activated sludge, the degradation of myrica rubra wastewater samples, after 25 h aeration for 96 h, the effect is better. Under this condition, the COD value was reduced at 72 mg/L, and the COD removal efficiency of myrica rubra wastewater was up to 93.39 %, and reached the two level discharge standard of municipal wastewater treatment.

  10. The behaviour of pharmaceuticals in anaerobic digester sludge

    OpenAIRE

    Campbell, Alison

    2013-01-01

    Pharmaceuticals are biologically active compounds that may be consumed in hundreds of tonnes per year, and which are excreted into municipal sewerage systems. Many pharmaceuticals persist during sewage treatment, and significant environmental risk has been linked to incomplete removal of pharmaceuticals. Evaluation of this risk is important and should be as representative as possible, taking into consideration all significant exposure routes and removal processes. Sludge treatment processes a...

  11. THE POSSIBILITIES OF NATURAL DEVELOPMENT OF ASH-SLUDGE BLENDS

    Directory of Open Access Journals (Sweden)

    Justyna Kiper

    2017-06-01

    Full Text Available Treatment of sewage results in creation of by-products such as screenings, fats, sand and the primary and secondary sludges – the most disposed elements in the technological process. Disposal of hazardous wastes is one of the most important issues in waste management. Regulation of the Minister of Economy dated 1 January 2016 (Dz.U. 2015 item 1277 – Journal of Laws which disallows the storage of sewage sludges, influenced the search for new solutions of their utilization. Forecasted increase in the amount of produced sludges and regulations in effect resulted in the increased interest in methods of utilization and studies on waste management. The study shows environmental possibilities of utilization of municipal sewage. The physicochemical and environmental properties of studied materials were determined. The studies were performed on sewer sludge obtained from mechanical biological municipal treatment plant “Pomorzany” in Szczecin. By-products of incineration biomass were used to prepare the sludge-ash mixes. Physicochemical properties were determined using reference methods according to current Standards and Instructions. To determine the environmental properties of sludge and mixes phytotoxicity test was used. The influence of soil’s toxicity on the plants was determined based on a method provided by the Regulation of the Minister of Environment dated 13 May 2004 on conditions in which it is assumed that waste is not hazardous (Dz.U. 2004 no. 128, item 1347 – Journal of Laws, “Determination of cytotoxic activity in garden cress”. Performed physicochemical tests and phytotoxicity test proved the applicability of prepared mixes in agriculture, remediation of anthropogenic soils and shutting down and revegetation of old landfills.

  12. Use of Natural Zeolite to Upgrade Activated Sludge Process

    Directory of Open Access Journals (Sweden)

    Hanife Büyükgüngör

    2003-01-01

    Full Text Available The objective of this study was to achieve better efficiency of phosphorus removal in an enhanced biological phosphorus removal process by upgrading the system with different amounts of natural zeolite addition. The system performance for synthetic wastewater containing different carbon sources applied at different initial concentrations of phosphorus, as well as for municipal wastewater, was investigated. Natural zeolite addition in the aerobic phase of the anaerobic/aerobic bioaugmented activated sludge system contributed to a significant improvement of phosphorus removal in systems with synthetic wastewater and fresh municipal wastewater. Improvement of phosphorus removal with regard to the control reactors was higher with the addition of 15 than with 5 g/L of natural zeolite. In reactors with natural zeolite addition with regard to the control reactors significantly decreased chemical oxygen demand, ammonium and nitrate, while higher increment and better-activated sludge settling were achieved, without changes in the pH-values of the medium. It was shown that the natural zeolite particles are suitable support material for the phosphate-accumulating bacteria Acinetobacter calcoaceticus (DSM 1532, which were adsorbed on the particle surface, resulting in increased biological activity of the system. The process of phosphorus removal in a system with bioaugmented activated sludge and natural zeolite addition consisted of: metabolic activity of activated sludge, phosphorus uptake by phosphate-accumulating bacteria adsorbed on the natural zeolite particles and suspended in solution, and phosphorus adsorption on the natural zeolite particles.

  13. Allegheny County Municipal Boundaries

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the municipal boundaries in Allegheny County. Data was created to portray the boundaries of the 130 Municipalities in Allegheny County the...

  14. Sewage sludges disinfection

    International Nuclear Information System (INIS)

    Alexandre, D.; Gevaudan, P.P.

    1977-01-01

    There is a hygienic risk in using biological sewage sludges for agriculture. Systematic analyses carried out on sludge samples obtained from purification plants in the Eastern and Southern part of France, show the almost uniform presence of pathogenic microorganisms. Some of them survive more than nine months after application to the soil. Conventional processes for disinfection, liming and heat, make the sludge unsuitable for agricultural use. On the other hand, irradiation involves no modification of structure and composition of sludges. Radiation doses required for disinfection vary according to the type of microorganism. Some of them are eliminated at rather low doses (200 krad), but mycobacteria, viruses and eggs of worms resist to more important doses. The security dose is estimated to be approx. 1000 krad

  15. Removal of Alkylphenols from Industrial and Municipal Wastewater

    Directory of Open Access Journals (Sweden)

    J. Derco

    2017-07-01

    Full Text Available The results of the study of removal of nonylphenol, octylphenol and their ethoxylates from real industrial and municipal wastewater are presented. Industrial wastewater was pre-treated by coagulation with FeCl3 and adsorption on zeolite, before discharging into municipal sewer system. Their removal efficiencies in primary sedimentation tank of municipal WWTP were very low. From the practical point of view, the highest and the most significant removal efficiencies within the whole WWTP were observed for nonylphenol and nonylphenol ethoxylates. Dominancy of abiotic mechanisms of alkylphenols removal follows from adsorption measurements. Activated sludge cultivated in lab-scale extended aeration tank accounted for relatively high adsorption affinity to these substances. Activated sludge sampled from municipal wastewater treatment plant (MWWTP receiving industrial wastewater containing alkylphenols accounted for very low adsorption affinity to these pollutants. Significantly higher removal efficiency of octylphenol ethoxylates was observed with the O3/granular active carbon (GAC process compared to the ozonation process alone. Lower toxicity impact of intermediates and products of ozonation treatment on Vibrio fischeri was measured in comparison to the O3/GAC process. Actually, the municipal WWTP effluent discharge concentration values complies with EQS values, including nonylphenols.

  16. Adaptive municipal electronic forms

    NARCIS (Netherlands)

    Kuiper, Pieternel; van Dijk, Elisabeth M.A.G.; Bondarouk, Tatiana; Ruel, Hubertus Johannes Maria; Guiderdoni-Jourdain, Karine; Oiry, Ewan

    Adaptation of electronic forms (e-forms) seems to be a step forward to reduce the burden for people who fill in forms. Municipalities more and more offer e-forms online that can be used by citizens to request a municipal product or service or by municipal employees to place a request on behalf of a

  17. Application of dielectric constant measurement in microwave sludge disintegration and wastewater purification processes.

    Science.gov (United States)

    Kovács, Petra Veszelovszki; Lemmer, Balázs; Keszthelyi-Szabó, Gábor; Hodúr, Cecilia; Beszédes, Sándor

    2018-05-01

    It has been numerously verified that microwave radiation could be advantageous as a pre-treatment for enhanced disintegration of sludge. Very few data related to the dielectric parameters of wastewater of different origins are available; therefore, the objective of our work was to measure the dielectric constant of municipal and meat industrial wastewater during a continuous flow operating microwave process. Determination of the dielectric constant and its change during wastewater and sludge processing make it possible to decide on the applicability of dielectric measurements for detecting the organic matter removal efficiency of wastewater purification process or disintegration degree of sludge. With the measurement of dielectric constant as a function of temperature, total solids (TS) content and microwave specific process parameters regression models were developed. Our results verified that in the case of municipal wastewater sludge, the TS content has a significant effect on the dielectric constant and disintegration degree (DD), as does the temperature. The dielectric constant has a decreasing tendency with increasing temperature for wastewater sludge of low TS content, but an adverse effect was found for samples with high TS and organic matter contents. DD of meat processing wastewater sludge was influenced significantly by the volumetric flow rate and power level, as process parameters of continuously flow microwave pre-treatments. It can be concluded that the disintegration process of food industry sludge can be detected by dielectric constant measurements. From technical purposes the applicability of dielectric measurements was tested in the purification process of municipal wastewater, as well. Determination of dielectric behaviour was a sensitive method to detect the purification degree of municipal wastewater.

  18. Sludge technology assessment

    International Nuclear Information System (INIS)

    Krause, T.R.; Cunnane, J.C.; Helt, J.E.

    1994-12-01

    The retrieval, processing, and generation of final waste forms from radioactive tank waste sludges present some of the most challenging technical problems confronting scientists and engineers responsible for the waste management programs at the various Department of Energy laboratories and production facilities. Currently, the Department of Energy is developing a strategy to retrieve, process, and generate a final waste form for the sludge that meets the acceptance criteria for the final disposition. An integral part of this strategy will be use of separation processes that treat the sludge; the goal is to meet feed criteria for the various processes that will generate the final waste form, such as vitrification or grouting. This document is intended to (1) identify separation technologies which are being considered for sludge treatment at various DOE sites, (2) define the current state of sludge treatment technology, (3) identify what research and development is required, (4) identify current research programs within either DOE or academia developing sludge treatment technology, and (5) identify commercial separation technologies which may be applicable. Due to the limited scope of this document, technical evaluations regarding the need for a particular separations technology, the current state of development, or the research required for implementation, are not provided

  19. Danish Municipal Planning in Change

    DEFF Research Database (Denmark)

    Møller, Jørgen

    Danish municipal planning at the entrance to the 2000 years, where many things in the everyday of planning are changed after pressure from the market, the state, the municipal organisations, the investors, the citizens and the planners themselves. In this situation of change there may be good reasons...... to bear in mind what the basic task of physical planning at a local level has actually been and to discuss both what it is at the moment and what it can turn into in the future. The paper may actually raise more questions than it answers. The reason is that well-known political, administrative structures...... are breaking up, that the fight for the planning competence in the open country is raging and that the protection of the nature-freindly legislation, for which the previous government was responsible, is under quick phasing-out, at the same time as the traditional professional urban planner standards...

  20. Danish Municipal planning in Change

    DEFF Research Database (Denmark)

    Møller, Jørgen

    2003-01-01

    Danish municipal planning at the entrance to the 2000 years, where many things in the everyday of planning are changed after pressure from the market, the state, the municipal organisation, the investors, the citizens and the planners themselves. In this situation of change there may be good reason...... to bear in mind what the basic task of physical planning at a local level has actually been and to discuss both what it is at the moment and what it can turn into in the future. The paper may actually raise more questions than it answers. The reason is that well-known political, administrative structures...... are breaking up, that the fight for planning competence in the open country is raging and that the protection og nature-friendly legislation, for which the previous gouvernment was responsible, is under quick phasing-out, at the same time as the traditional professional urban planner standards are challenged...

  1. Sludge Stabilization Campaign blend plan

    International Nuclear Information System (INIS)

    De Vries, M.L.

    1994-01-01

    This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material

  2. Test plan, sludge retrieval, sludge packaging

    International Nuclear Information System (INIS)

    Feigenbutz, L.V.

    1994-01-01

    This document provides direction for the cold testing of tools, equipment and systems which will be installed and operated in K-East (KE) Basin in support of the sludge retrieval and packaging project. The technical uncertainties related to the effectiveness of sludge retrieval procedures and equipment require that cold testing be completed before installation in KE Basin to identify and resolve existing problems, and to optimize the efficiency of all equipment and systems used. This plan establishes the responsibilities, test requirements, and documentation requirements necessary to complete cold tests of: (1) equipment with no potential for plant use; (2) prototype equipment and systems which may be upgraded for use in K-Basin; and (3) plant equipment and systems requiring cold acceptance testing prior to plant use. Some equipment and systems may have been subject to a formal design review and safety assessment; the results of which will be included as supporting documents to the operational readiness review (ORR)

  3. The compost with the OFMSW as a solution for the sludges from the wastewater purification plants; Compostaje con FORSU como una solucion para los fangos de depuradora

    Energy Technology Data Exchange (ETDEWEB)

    Chica Perez, A.; Diaz Rubio, M. M.; Mohedo Gaton, J. J.; Martin Martin, A. [Universidad de Cardoba (Spain); Revilla Alvarez, J. R.

    2001-07-01

    The correct management of the sludges coming from the municipal wastewater purification plants (mwpp) is an unsolved problem in many cases and its volume is quickly increasing. As a solution for its treatment and disposal the composting process of the sludges combined with the organic fraction of municipal solid wastes (OFMSW) selectively collected is proposed in this work. A suitable compost for agricultural use is obtained. Using respirometer methods better than using other analytical parameters can monitor the stabilisation process of the mixture of sludges from MWPP and OFMSW. The measurement of the maximum oxygen intake specific rate indicates an appropriate stabilisation of the mixture after third treatment month. (Author) 32 refs.

  4. Designing a Municipality

    DEFF Research Database (Denmark)

    Jungersen, Ulrik; Hansen, Poul H. Kyvsgård

    2014-01-01

    Can a municipality be designed? The municipality Kolding in the southern part of Denmark asked this question. The idea emerged as a response to a recognized need for new ways of branding and developing the municipality. It is an ongoing process that was kicked off in 2012 and this paper is theref......Can a municipality be designed? The municipality Kolding in the southern part of Denmark asked this question. The idea emerged as a response to a recognized need for new ways of branding and developing the municipality. It is an ongoing process that was kicked off in 2012 and this paper...... is therefore focusing primarily on the process of changing the perception of how to organize development in a municipality. The most important elements in transforming the whole development setup are described. Finally, a short case describing one of the significant results is included....

  5. ZEOLITIZATION OF SEWAGE SLUDGE ASH WITH A FUSION METHOD

    Directory of Open Access Journals (Sweden)

    Jolanta Latosińska

    2016-11-01

    Full Text Available The study shows the results of zeolitization of municipal sewage sludge ash with the indirect fusion method followed by a hydrothermal method. The zeolitization of sewage sludge ash was conducted at the melting temperature of 550°C and the melting time of 60 minutes, crystallization temperatures of 60°C and 90°C, crystallization time of 6 hours and the SSA:NaOH ratio of 1:1.8; 1:1.4. The research of modified sewage sludge ashes included the observation of changes of ash particles surface and the identification of crystalized phases. The zeolitization of sewage sludge ash at the ratio of SSA:NaOH 1.0:1.4 did not cause the formation of zeolite phases. On the other hand, the zeolitization at the ratio of SSA:NaOH 1.0:1.8 resulted in the formation of desired zeolite phases such as zeolite Y (faujasite and hydroxysodalite. The presented method of sewage sludge ash zeolitization allows to obtain highly usable material. Synthesized zeolites may be used as adsorbents and ion exchangers. They can be potentially used to remove heavy metals as well as ammonia from water and wastewater.

  6. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

    Meulepas, Roel J W

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342μgg-1 of copper, 487μgg-1 of lead, 793μgg-1 of zinc, 27μgg-1 of nickel and 2.3μgg-1 of cadmium. During the anaerobic acidification of 3gdry weightL-1 waste activated sludge, 80-85% of the copper, 66-69% of the lead, 87% of the zinc, 94-99% of the nickel and 73-83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead.

  7. Aerobic Biological treatment of municipal wastewaters and pig slurry and the associated bacteriological and parasitological risks

    Energy Technology Data Exchange (ETDEWEB)

    Venglovsky, J.; Sasokova, N.; Juris, P.; Papajova, I.; Vargova, M.; Ondrasovicova, O.; Ondrasovic, M.

    2009-07-01

    The aim of the present study was to investigate the bacteriological and parasitological risk associated with the products of aerobic treatment of pig slurry and municipal sewage. We focused on the quality of effluents and on sewage sludge and pig slurry solids from two wastewater treatment plants (pig slurry WWTP.1; municipal wastewater WWTP-2 with regard to place counts of selected groups of bacteria (mesophilic, coliform, faecal coliform) and the efficiency of their removal. (Author)

  8. Aerobic Biological treatment of municipal wastewaters and pig slurry and the associated bacteriological and parasitological risks

    International Nuclear Information System (INIS)

    Venglovsky, J.; Sasokova, N.; Juris, P.; Papajova, I.; Vargova, M.; Ondrasovicova, O.; Ondrasovic, M.

    2009-01-01

    The aim of the present study was to investigate the bacteriological and parasitological risk associated with the products of aerobic treatment of pig slurry and municipal sewage. We focused on the quality of effluents and on sewage sludge and pig slurry solids from two wastewater treatment plants (pig slurry WWTP.1; municipal wastewater WWTP-2 with regard to place counts of selected groups of bacteria (mesophilic, coliform, faecal coliform) and the efficiency of their removal. (Author)

  9. Municipal sludge as source of nitrogen and phosphorus in perennial ...

    African Journals Online (AJOL)

    2013-07-11

    Jul 11, 2013 ... arranged in a complete block design comprising 4 replications of 4 treatments planted to Eragrostis curvula. ... cially when they enter the food chain. For these reasons ...... Department of Ecology, Seattle, WA. HUANG XL ...

  10. Anaerobic bioleaching of metals from waste activated sludge

    International Nuclear Information System (INIS)

    Meulepas, Roel J.W.; Gonzalez-Gil, Graciela; Teshager, Fitfety Melese; Witharana, Ayoma; Saikaly, Pascal E.; Lens, Piet N.L.

    2015-01-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g −1 of copper, 487 μg g −1 of lead, 793 μg g −1 of zinc, 27 μg g −1 of nickel and 2.3 μg g −1 of cadmium. During the anaerobic acidification of 3 g dry weight L −1 waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner

  11. Transformation of Silver Nanoparticles in Sewage Sludge during Incineration.

    Science.gov (United States)

    Meier, Christoph; Voegelin, Andreas; Pradas del Real, Ana; Sarret, Geraldine; Mueller, Christoph R; Kaegi, Ralf

    2016-04-05

    Silver nanoparticles (Ag-NP) discharged into the municipal sewer system largely accumulate in the sewage sludge. Incineration and agricultural use are currently the most important strategies for sewage sludge management. Thus, the behavior of Ag-NP during sewage sludge incineration is essential for a comprehensive life cycle analysis and a more complete understanding of the fate of Ag-NP in the (urban) environment. To address the transformation of Ag-NP during sewage sludge incineration, we spiked metallic Ag(0)-NP to a pilot wastewater treatment plant and digested the sludge anaerobically. The sludge was then incinerated on a bench-scale fluidized bed reactor in a series of experiments under variable conditions. Complementary results from X-ray absorption spectroscopy (XAS) and electron microscopy-energy dispersive X-ray (EM-EDX) analysis revealed that Ag(0)-NP transformed into Ag2S-NP during the wastewater treatment, in agreement with previous studies. On the basis of a principal component analysis and subsequent target testing of the XAS spectra, Ag(0) was identified as a major Ag component in the ashes, and Ag2S was clearly absent. The reformation of Ag(0)-NP was confirmed by EM-EDX. The fraction of Ag(0) of the total Ag in the ashes was quantified by linear combination fitting (LCF) of XAS spectra, and values as high as 0.8 were found for sewage sludge incinerated at 800 °C in a synthetic flue gas atmosphere. Low LCF totals (72% to 94%) indicated that at least one relevant reference spectrum was missing in the LCF analysis. The presence of spherical Ag-NP with a diameter of incineration, as demonstrated in this study, needs to be considered in the life cycle assessment of engineered Ag-NP.

  12. Anaerobic bioleaching of metals from waste activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Meulepas, Roel J.W., E-mail: roel.meulepas@wetsus.nl [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Gonzalez-Gil, Graciela [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Teshager, Fitfety Melese; Witharana, Ayoma [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Saikaly, Pascal E. [King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Lens, Piet N.L. [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands)

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g{sup −1} of copper, 487 μg g{sup −1} of lead, 793 μg g{sup −1} of zinc, 27 μg g{sup −1} of nickel and 2.3 μg g{sup −1} of cadmium. During the anaerobic acidification of 3 g{sub dry} {sub weight} L{sup −1} waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner.

  13. Sludge pumping in water treatment

    International Nuclear Information System (INIS)

    Solar Manuel, M. A.

    2010-01-01

    In water treatment processes is frequent to separate residual solids, with sludge shape, and minimize its volume in a later management. the technologies to applicate include pumping across pipelines, even to long distance. In wastewater treatment plants (WWTP), the management of these sludges is very important because their characteristics affect load losses calculation. Pumping sludge can modify its behavior and pumping frequency can concern treatment process. This paper explains advantages and disadvantages of different pumps to realize transportation sludge operations. (Author) 11 refs.

  14. EVALUATION OF OXYGEN-ENRICHED MSW/SEWAGE SLUDGE CO-INCINERATION DEMONSTRATION PROGRAM

    Science.gov (United States)

    This report provides an evaluation of a two-phased demonstration program conducted for the U.S. Environmental Protection Agency's Municipal Solid Waste Innovative Technology Evaluation Program, and the results thereof, of a recently developed method of sewage sludge managemen...

  15. Degradation of triclosan and triclocarban and formation of transformation products in activated sludge using benchtop bioreactors

    Science.gov (United States)

    Benchtop bioreactors were run aerobically with activated sludge samples collected from a large municipal wastewater treatment plant (WWTP) to understand how increased hydraulic retention time (HRT) and varying treatment temperatures (21°C and 30°C) impact concentrations of the endocrine disrupting a...

  16. Moorella stamsii sp. nov., a new anaerobic thermophilic hydrogenogenic carboxydotroph isolated from digester sludge

    NARCIS (Netherlands)

    Alves, J.I.; Gelder, van A.H.; Alves, M.M.; Sousa, D.Z.; Plugge, C.M.

    2013-01-01

    A novel anaerobic, thermophilic, carbon monoxide-utilizing bacterium, strain E3-O, was isolated from anaerobic sludge of a municipal solid waste digester. Cells were straight rods, 0.6 to 1µm in diameter and 2 to 3 µm in length, growing as single cells or in pairs. Cells formed round terminal

  17. Activated sludge process simulator ASP-Sim, Part-1: Bod and ...

    African Journals Online (AJOL)

    The most commonly used biological treatment of municipal and industrial wastewater is the Activated Sludge Process. The design of activated process is usually done manually; this is ... is a useful tool for predicting the effect of temperature on design and operation of completely mixed activated plant design and operation.

  18. RELATIONSHIP BETWEEN SLUDGE DEWATERABILITY NUMBER ...

    African Journals Online (AJOL)

    A representative of a sludge sample collected from the same source was filtered under the same environmental condition and the result analysed with two different concepts. One method of analysis uses Sludge Dewaterability Number, while the second employed the Carman's Specific resistance concept in sludge ...

  19. Sewage sludges disinfection

    International Nuclear Information System (INIS)

    Alexandre, D.

    1977-01-01

    There is an hygienic risk in using biological sewage sludges for agriculture. Systematic analysis carried out on sludges samples obtained from purification plants in East and South part of France, show the almost uniform presence of pathogenic microorganisms. Some of it survive more than 9 months after soil application. Conventional process for disinfection: liming and heat are not suitable for agricultural use. On the other hand, irradiation involves no modification in structure and composition of sludges. Radiation doses required for disinfection vary according to microorganisms. If some of them are eliminated with rather light doses (200 krad) mycobacteria, viruses and eggs of worms resist to more important doses. Security dose is estimated around 1000 krad

  20. Pilot tests in enhanced ultrasonic disintegration of sewage sludge; Pilotversuche zur Intensivierung der Schlammfaulung durch Klaerschlammdesintegration mit Ultraschall

    Energy Technology Data Exchange (ETDEWEB)

    Nickel, K.; Tiehm, A.; Neis, U. [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Arbeitsbereich Abwasserwirtschaft

    1999-07-01

    The work has the objective to optimize ultrasonic disintegration of sewage sludge in permant routine operation. Anaerobic degradation of disintegrated crude and excess sludge was investigated on a pilot scale at a municipal sewage treatment plant. (orig.) [German] Ziel dieser Arbeit ist die Optimierung der Klaerschlammdesintegration mit Ultraschall im praktischen Dauerbetrieb. Der anaerobe Abbau von desintegriertem Roh- und Ueberschussschlamm wurde im Pilotmassstab vor Ort auf einer kommunalen Klaeranlage untersucht. (orig.)

  1. Charcoal from paper sludge

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, M

    1980-03-06

    Paper sludge containing less than or equal to 50% water is mixed with coffee shells and greater than or equal to 1 almond shells, orange skin, walnut shells, or bean jam waste, compacted, and dry distilled at 300-600 degrees to prepare charcoal. Thus, 1 ton of paper sludge was mixed with 100 kg each of coffee shells, almond shells, orange skin, and walnut shells; compacted and dry distilled 24 hours at approximately 450 degrees. The calorific value of the charcoal produced was approximately 7300 kcal/kg.

  2. Biogas recovery from tanning sludges. Anaerobic digestion of lime fleshings, tanning sludge, and unhairing baths, laboratory and pilot scale results

    Energy Technology Data Exchange (ETDEWEB)

    Fendrup, W.; Hansen, S.; Petersen, G.

    1983-11-01

    Mesophilic anaerobic digestion of various types of tannery and other wastes, separately or in mixtures, has been investigated. The following materials were used: Lime fleshings, Tannery sludge, Beamhouse sludge, Municipal sludge, Chrome leather shavings, Liquid manure. The investigations have shown anaerobic digestion to be possible with untanned tannery wastes as well as tannery effluent sludge as a substrate. Specially high gas yields were found by digestion of mixtures of tannery wastes and manure. This may be applicable to mixtures of tannery wastes and municipal sludge, too. The gas contains 0.5 - 1.0% H2S. About 25% of the gross energy (methane) output is used for sustaining the temperature necessary for the digestion together with the mixing and conveying of the material to be digested. If electricity is produced, 25% of the gross output is obtained as useful electric energy and 35% as useful thermic energy. If the gas is burned, 60% of the gross output is obtained as useful thermic energy. With the price relations found in most countries (e.g. Denmark, Finland and Sweden) it will be most profitable to produce electricity, whereas in some cases (e.g. Norway) the opposite may be true. The energy requirement of a typic Scandinavian tannery is 14.200 MJ/t rawhide as thermic energy and 2.300 MJ/t rawhide as electric energy, which means that maximum 14% of the thermic energy requirement or maximum 35% of the electricity requirement could be covered by the wastes digestion. Profitability calculations are made for each Scandinavian country. The calculations show that too small digestion plants are not profitable.

  3. FINE PARTICAL AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt; Wayne S. Seames; Art Fernandez

    2003-09-21

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and pulverized coal. The objective was to determine potential tradeoffs between CO{sub 2} mitigation through using a CO{sub 2} neutral fuel, such as municipal sewage sludge, and the emergence of other potential problems such as the emission of toxic fly ash particles. The work led to new insight into mechanisms governing the partitioning of major and trace metals from the combustion of sewage sludge, and mixtures of coal and sewage sludge. The research also showed that the co-combustion of coal and sewage sludge emitted fine particulate matter that might potentially cause greater lung injury than that from the combustion of either coal alone or municipal sewage sludge alone. The reason appeared to be that the toxicity measured required the presence of large amounts of both zinc and sulfur in particles that were inhaled. MSS provided the zinc while coal provided the sulfur. Additional research showed that the toxic effects could most likely be engineered out of the process, through the introduction of kaolinite sorbent downstream of the combustion zone, or removing the sulfur from the fuel. These results are consequences of applying ''Health Effects Engineering'' to this issue. Health Effects Engineering is a new discipline arising out of this work, and is derived from using a collaboration of combustion engineers and toxicologists to mitigate the potentially bad health effects from combustion of this biomass fuel.

  4. Composting Used as a Low Cost Method for Pathogen Elimination in Sewage Sludge in Mérida, Mexico

    Directory of Open Access Journals (Sweden)

    Rafael Rojas-Herrera

    2013-07-01

    Full Text Available Spreading sewage sludge from municipal wastewater (MWW treatment on land is still a common practice in developing countries. However, it is well known that sewage sludge without special treatment contains various pollutants, which are (reintroduced into the environment by sludge landspreading and which might in turn have harmful effects on the environment and human health. This is more dangerous in places like Merida, Mexico, where soil is calcareous with fractures along the ground and thin layers of humus. Consequently, any liquid and semisolid wastes have the potential of percolating to the subsurface and contaminate the aquifer. The main aim of this work was using composting as a low cost process to eliminate pathogens contained in sewage sludge from MWW treatment in order to use the final product for land spreading in a safe way for both environment and human health. Two piles for composting process at real scale were settled using a mixture of sewage sludge from municipal waste water and green waste. Composting was carried out by windrow process and it was monitored during four weeks. Concentration of helminth eggs, salmonella and faecal coliforms were measured twice a week to observe its behavior and, as a control process, Temperature, Moisture Content (MC, and pH were also measured. After 30 days of composting sludge from municipal waste water system, salmonella was eliminated by 99%, faecal coliforms by 96% and helminth eggs by 81%. After 3 months compost reached GI = 160%, so did not show any phytotoxicity to seeds.

  5. An innovative process for treatment of municipal wastewater with superior charcteristics compared to traditional techologies

    DEFF Research Database (Denmark)

    Schmidt, Jens Ejbye; Fitsios, E.; Angelidaki, Irini

    2002-01-01

    An innovative treatment process for municipal sewage, which results in low sludge production, low energy consumption, high COD removal and high energy and nutrients recovery, is described. The organic matter will primarly be removed through anaerobic degradation using high-flow reactors. For nitr...

  6. Marketing marketing

    NARCIS (Netherlands)

    dr. Karel Jan van Alsem

    2013-01-01

    In deze installatierede betoogt Karel Jan Alsem dat marketing een grotere strategische rol in organisaties zou moeten krijgen. Want marketing is bij uitstek de verbinding tussen klantwensen en het DNA van een organisatie. Doordat merken gemiddeld voor mensen niet heel belangrijk zijn, is goede

  7. Municipalities as facilitators, regulators and energy consumers

    DEFF Research Database (Denmark)

    Lybæk, Rikke; Kjær, Tyge

    2015-01-01

    Biogas provides many potential benefits as far as renewable energy production, environmental protection and job creation etc. Insufficient initiatives from government/municipalities however hamper more biogas plants to be established, and hence that the large manure potential, and other types...... of digestible organic waste materials, are being utilized for energy purposes. By looking at municipalities as energy consumer’s, that constitutes a local market for biogas, as regulator’s, enforcing new requirements and regulations on the biogas sector, and finally as facilitator’s, assisting and helping...

  8. Management experience on microthrix parvicella bulking in an activated sludge wastewater treatment plant

    International Nuclear Information System (INIS)

    De Bortoli, N.; Mion, M.; Di Giorgio, G.; Goi, D.

    2005-01-01

    Activated sludge wastewater treatment processes may give inefficiencies due to biological imbalances involving biomass. In fact, external causes as temperature lowering can increase the proliferation of the filamentous bacterium Microthrix parvicella into activated sludge flocks. Microthrix parvicella increases may create dangerous bulking phenomena compromising secondary settling without varying bio-kinetic parameters. In this case of study, a method to defeat growth of Microthrix parvicella has been set up. Aluminium poly-chloride (PAC) has been added to activated sludge contained into oxidation tanks of a municipal wastewater treatment plant, where a large growth of Microthrix parvicella has been periodically observed. It has been demonstrated that a definite PAC concentration can reduce Microthrix parvicella proliferation into activated sludge flocks so bulking phenomena can be well reduced [it

  9. Comparison between different models for rheological characterization of sludge from settling tank

    Directory of Open Access Journals (Sweden)

    Malczewska Beata

    2017-09-01

    Full Text Available The municipal sludge characterized non-Newtonian behaviour, therefore the viscosity of the sewage sludge is not a constant value. The laboratory investigation was made using coaxial cylinder with rotating torque and gravimetric concentration of the investigated sludge ranged from 4.40% to 2.09%. This paper presents the investigation on the effect of concentration of rheological sludge behaviour. The three different rheological models: Bingham (plastic model, Ostwald-de Waele (power-law, Hershel-Bulkley’s were calculated by fitting the experimental data of shear stress as a function of shear rate to these models. In this study, the 3-parameter Herschel- Bulkley’s model fits the experimental data best.

  10. Ultrasonic reduction of excess sludge from the activated sludge system

    International Nuclear Information System (INIS)

    Zhang Guangming; Zhang Panyue; Yang Jinmei; Chen Yanming

    2007-01-01

    Sludge treatment has long become the most challenging problem in wastewater treatment plants. Previous studies showed that ozone or chlorine effectively liquefies sludge into substrates for bio-degradation in the aeration tank, and thus reduces the excess sludge. This paper employs ultrasound to reduce the excess sludge from the sequential batch reactor (SBR) system. Partial sludge was disintegrated into dissolved substrates by ultrasound in an external sono-tank and was then returned to the SBR for bio-degradation. The results showed that ultrasound (25 kHz) effectively liquefied the sludge. The most effective conditions for sludge reduction were as following: sludge sonication ratio of 3/14, ultrasound intensity of 120 kW/kgDS, and sonication duration of 15 min. The amount of excess sludge was reduced by 91.1% to 17.8 mg/(L d); the organic content and settleability of sludge in the SBR were not impacted. The chemical oxygen demand (COD) removal efficiency was 81.1%, the total nitrogen (TN) removal efficiency was 17-66%, and high phosphorus concentration in the effluent was observed

  11. Bacteriology of activated sludge

    NARCIS (Netherlands)

    Gils, van H.W.

    1964-01-01

    The bacteriology and biochemistry of activated sludge grown in domestic waste water or fed with synthetic media were studied. The nature of the flocs was investigated by determining morphological and physiological characteristics of many strains isolated.

    Predominant bacteria were

  12. Activated Sludge Rheology

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Horn, Willi; Helmus, Frank

    2013-01-01

    Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling and filtr...... rheological measurements. Moreover, the rheological models are not very trustworthy and remain very “black box”. More insight in the physical background needs 30 to be gained. A model-based approach with dedicated experimental data collection is the key to address this.......Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling......, leading to varying results and conclusions. In this paper, a vast amount of papers are critically reviewed with respect to this and important flaws are highlighted with respect to rheometer choice, rheometer settings and measurement protocol. The obtained rheograms from experimental efforts have...

  13. Anaerobic treatment of slaughterhouse waste using a flocculant sludge UASB reactor. [Upflow Anaerobic Sludge Blanket

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, S.; de Zeeuw, W.; Lettinga, G.

    1984-01-01

    This study was carried out to assess the feasibility of using the upflow anaerobic sludge blanket (UASB) process for the one-step anaerobic treatment of slaughterhouse waste, which contains approximately 50% insoluble suspended COD. Batch experiments, as well as continuous experiments, were conducted. The continuous experiments were carried out in a 30 cubic m UASB pilot-plant with digested sewage sludge from the municipal sewage treatment plant of Ede, The Netherlands (Ede-2 sludge), used as seed. Initially the UASB pilot-plant was operated at a temperature of 30 degrees C, but, 20 weeks after the start-up, the temperature was reduced to 20 degrees C, because application of the process at this lower temperature might be quite attractive for economic reasons. The process can be started up at an organic space load of 1 kg COD/m/sup 3/ day (sludge load, 0.11 kg/COD kg VSSday) and at a liquid detention time of 35 h at a process temperature of 30 degrees C. Once started up, the system can satisfactorily handle organic space loads up to 3.5 kg COD/m/sup 3/ day at a liquid detention time of 8 hours at temperatures as low as 20 degrees C. A treatment efficiency up to 70% on a COD tot basis, 90% on a COD sol basis and 95% on a BOD5 sol basis was smoothly approached. Temporary shock loads up to 7 kg COD/m/sup 3/ day during the daytime at a liquid detention time of 5 h can well be accommodated provided such a shock load is followed by a period of underloading, e.g. at night. The methane yield amounted to 0.28 NM/sup 3/ per kilogram of COD removed: the methane content of the biogas from the wastewater varied between 65 and 75%. 19 references.

  14. Waste Sites - Municipal Waste Operations

    Data.gov (United States)

    NSGIC Education | GIS Inventory — A Municipal Waste Operation is a DEP primary facility type related to the Waste Management Municipal Waste Program. The sub-facility types related to Municipal Waste...

  15. EFFECT OF FLY ASHES AND SEWAGE SLUDGE ON Fe, Mn, Al, Si AND Co UPTAKE BY GRASS MIXTURE

    Directory of Open Access Journals (Sweden)

    Jacek Antonkiewicz

    2014-07-01

    Full Text Available Application of sewage sludge for environmental management of fly ashes landfill site affects chemical composition of plants. The aim of the present investigations was learning the effect of growing doses of municipal sewage sludge on the yield and uptake of Fe, Mn, Al, Si and Co by grass mixture used for environmental management of fly ashes landfill. The experimental design comprised of 5 objects differing by a dose of municipal sewage sludge supplied per 1 hectare: I. control, II. 25 t d.m., III. 50 t d.m., IV. 75 t d.m. and V. 100 t d.m. Application of sewage sludge resulted in the increase in yield. The content of analyzed elements in the grass mixture depended significantly on sewage sludge dose. Increasing doses of sewage sludge caused marked increase in Mn and Co contents, while they decreased Fe, Al and Si contents in the grass mixture. It was found that growing doses of sewage sludge caused an improvement of Fe to Mn ratio value in the grass mixture. Assessing the element content in the grass mixture in the view of forage value, it was found that Fe and Mn content did not meet the optimal value. Si content in plants was below the optimal value.

  16. Wastewater and sludge reuse in agriculture

    Science.gov (United States)

    Kalavrouziotis, Ioannis

    2016-04-01

    The reuse of Municipal wastewaters (TMWW) for irrigation of crops, and of sludge for the amendment of soils, is a multidimensional disposal practice aiming at: (i) minimizing the environmental problems by releasing the pressure exerted by these two inputs on the environment, (ii) providing the growing plants with water and nutrients and (ii) improving soil fertility and productivity, The research work conducted in our University in relation to accomplishing a safe reuse has been focused on the study of the following aspects of reuse: (i) heavy metal accumulation in soils and plants with emphasis on their edible part. This aspect has been studied by conducting a series of experiments aiming at the study of the accumulation of heavy metals in soils, and in plant roots, stalks, leaves and fruits. The conclusions drawn so far with regard to the order of accumulation of heavy metals are: Roots>leaves>stalks>fruits ( edible parts) (ii) interactions between heavy metals, plant nutrients and soil chemical and physical properties. After the examinations of hundreds of interactions, and the development of a quantification of the interactions contribution, it was found that considerable quantities of heavy metals and nutrients are contributed to the soil and to various plant parts , emphasizing the important role of the elemental interactions in plants.(iii) assessment of soil pollution with heavy metals based on pollution indices, Three pollution Indices have been established by our research team and were proposed internationally for application in actual practice for the prediction of soil pollution due to long term reuse of wastewater and sludge. These indices are as follows: (a) Elemental pollution Index (EPI), (b) Heavy Metal Load (HML), and (c) Total Concentration Factor (TCF) and (iv) construction of a computer program for the control of the reuse of TMWW and sludge, and forecasting soil pollution due to accumulation of heavy metal by means of pollution indices.

  17. Esco in Danish municipalities

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Hansen, Jesper Rohr; Nielsen, Susanne Balslev

    2012-01-01

    Purpose: The aim of this paper is to discuss the possible benefits of involving Energy Service Companies (ESCO) in realising energy savings in municipalities, and how ESCO projects can be formulated very differently in the various municipalities, according to building volume, use of technologies......, energy savings, type of collaboration etc. Background: Since 2008, several Danish municipalities have started energy retrofitting of municipal buildings, based on contracts with Energy Service Companies. In spite of the strong growth of ESCOs, there is also widespread scepticism about ESCO, as many...... approaches are being used in Danish municipalities, which we label the basic, the integrated and the strategic ESCO approaches. The three approaches include different ambitions, technologies, economies and innovation potentials. Whereas the basic approach implies a ‘traditional’ guarantee-based model...

  18. Polybrominated diphenyl ethers in sewage sludge from Shanghai, China: possible ecological risk applied to agricultural land.

    Science.gov (United States)

    Yang, Chao; Meng, Xiang-Zhou; Chen, Ling; Xia, Siqing

    2011-10-01

    Ideally, agricultural use is a treatment for the sewage sludge generated from municipal wastewater. However, this treatment probably causes ecological risks due to the occurrence of organic contaminants in sludge, which has attracted rising concerns recently. To assess the possible ecological risk, in this study, sewage sludge samples were collected from 28 wastewater treatment plants (WWTPs) in Shanghai, China for exploring the level and profile of polybrominated diphenyl ethers (PBDEs). The mean concentration of Σ18PBDE (sum of all target analytes except for BDE-209) was at the low end of global range. However, we found the highest reported BDE-209 levels (34,900 ng g(-1) dw) in sewage sludge/biosoilds to date. The annual mass loadings of penta-BDE, octa-BDE, and deca-BDE were 3.6, 0.6, and 763 kg through sludge, respectively. Following sludge application in agricultural land, the concentrations of penta-BDE, octa-BDE, and deca-BDE in soil were 0.19, 0.03, and 39.5 ng g(-1), respectively. Preliminary results indicate that the ecological risk of soil in organisms exposed to PBDEs was relatively low. Nevertheless, further studies are needed to explore the fate of PBDEs in sewage sludge due to no restriction on the usage and production of PBDEs products in China currently. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Effect of gamma irradiation and moisture on microbiological load of sewage sludge

    International Nuclear Information System (INIS)

    Al-Bachir, M.; Al-Adawi, M. A.; Shamma, M.

    2002-07-01

    Concentrated municipal sewage sludge, stored for 2, 4, and 6 months, with moisture content of 2, 20, 40, 60, and 80% were exposed to doses of 0, 1, 2, 3, 4, and 5 kGy in a 60 Co package irradiator. Immediately after irradiation, total microbial count, bacterial pathogens in sewage sludge was determined. Techno-economic feasibility of irradiated sewage according to the moisture content in sewage sludge and the needed irradiation dose to eliminate pathogens was evaluated. The results indicated that, all tested sewage sludge sample, bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and e. coli, were detected. Used doses of gamma irradiation reduced the counts of microorganisms. D 1 0 of total count decreased with increasing the moisture level of sewage sludge. The lowest lethal dose for bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and e. coli is over 5 kGy and 1 kGy in air dried and watered sludge with more than 40% sewage sludge respectively, for samples taken at 2, 4 and 6 months of storage. (author)

  20. Feasibility of bioleaching combined with Fenton-like reaction to remove heavy metals from sewage sludge.

    Science.gov (United States)

    Zhu, Yi; Zeng, Guangming; Zhang, Panyue; Zhang, Chang; Ren, Miaomiao; Zhang, Jiachao; Chen, Ming

    2013-08-01

    Feasibility of bioleaching combining with Fenton-like reaction to remove heavy metals from sewage sludge was investigated. After 5-day bioleaching, the sludge pH decreased from 6.95 to 2.50, which satisfied the acidic conditions for Fenton-like reaction. Meanwhile, more than 50% of sludge-borne heavy metals were dissolved except for Pb. The bioleached sludge was further oxidized with Fenton-like reaction, with an optimal H2O2 dosage of 5 g/L, the Cu, Zn, Pb and Cd removal reached up to 75.3%, 72.6%, 34.5% and 65.4%, respectively, and the residual content of heavy metals in treated sludge meets the requirement of Disposal of Sludge from Municipal Wastewater Treatment Plant - Control Standards for Agricultural Use (CJ/T 309-2009) of China for A grade sludge. Bioleaching combined with Fenton-like reaction was the most effective method for heavy metal removal, compared with 15-day bioleaching and inorganic acid leaching with 10% H2SO4, 10% HCl and 10% HNO3. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Reuse of wastewater sludge with marine clay as a new resource of construction aggregates.

    Science.gov (United States)

    Tay, J H; Show, K Y; Lee, D J; Hong, S Y

    2004-01-01

    The disposal of sludge from wastewater treatment presents highly complex problems to any municipality. Most of the sludge disposal methods have varying degrees of environmental impact. Hence, it is necessary to explore potential areas of reuse in order to alleviate sludge disposal problems and to conserve natural resources. Industrial sludge and marine clay are two forms of high-volume wastes. Using these wastes as a resource of raw materials to produce construction aggregates would enable large-scale sludge reuse. The aggregates were produced at various sludge-clay combinations containing 0, 20, 50, 80 and 100% clay contents, respectively. The pelletized aggregates displayed lower particle densities ranged between 1.48 and 2.25 g/cm3, compared to the density of granite at 2.56 g/cm3. Good 28-day concrete compressive strength of 38.5 N/mm2 achieved by the 100% sludge aggregate was comparable to the value of 38.0 N/mm2 achieved of the granite control specimens. The leachate contamination levels from the aggregates after 150 days were found acceptable when used in concrete, indicating insignificant environmental contamination. The heat flow study showed increases in heat flow at the temperatures of 480 degrees C and between 660 degrees C and 900 degrees C, indicating a need for the extension of heating time around these temperatures.

  2. INFLUENCE OF SLUDGE RECIRCULATION ON NUTRIENT REMOVAL IN SUBMERGED MEMBRANE BIOREACTORS

    Directory of Open Access Journals (Sweden)

    María Casamitjanaa Causa

    2015-06-01

    Full Text Available Membrane bioreactors (MBR technology is a well-developed wastewater treatment process; however, the integrated operation between biological reactions and physical filtration has been poorly studied. Among other operational parameters, optimal control of sludge recirculation can enhance nitrogen and phosphorous removal processes, but the effects on sludge filterability is not clear. In this paper, different recirculation flow rates were tested to evaluate consequences on sludge filterability and nutrient removal in a MBR-UCT pilot plant treating real municipal wastewater. Three distinct sludge recirculation flows were studied during 10 weeks [external recirculation (from the membrane tank to the anoxic reactor, anoxic recirculation (from the aerobic to the anoxic reactor and anaerobic recirculation (from the anoxic to the anaerobic reactor]. The obtained results have shown that anaerobic recirculation affected nutrient removal in an inversely proportional way, whereas anoxic recirculation had a directly proportional effect. Referring sludge characteristics, filterability and capillarity suction time (CST remained independent of sludge recirculation, whereas CST is proportional to transmembrane pressure (TMP, which seems to depend on external and anoxic sludge recirculation.

  3. Radioactivity in sludge: tank cleaning procedures and sludge disposal

    International Nuclear Information System (INIS)

    Bradley, D.A.

    1995-01-01

    In the oil and gas industry management of alpha-active sludge is made more complex by the presence of hydrocarbons and heavy metals. This presentation discusses the origin of radioactivity in sludge, management of risk in terms of safe working procedures, storage and possible disposal options. The several options will generally involve aspects of dilution or of concentration; issues to be discussed will include sludge farming, bioremediation and incineration. (author)

  4. Minimization of Excess Sludge in Activated Sludge Systems

    Directory of Open Access Journals (Sweden)

    Sayed Ali Reza Momeni

    2006-01-01

    Full Text Available The disposal of excess sludge from wastewater treatment plant represents a rising challenge in activated sludge processes. Hence, the minimization of excess sludge production was investigated by increasing the dissolved oxygen in aeration basin. Units of the pilot include: Primary sedimentation tank, aeration basin, secondary sedimentation tank, and return sludge tank. Volume of aeration basin is 360 l and influent flow rate is 90 L/h. Influent of pilot is taken from effluent of grit chamber of Isfahan's North Wastewater treatment plant. The experiments were done on different parts of pilot during the 5 month of study. Results show that increase of dissolved oxygen in aeration tank affect on decrease of excess sludge. Increase of dissolved oxygen from 0.5 to 4.5 mg/L resulted in 25% decrease of excess sludge. Variation of dissolved oxygen affect on settleability of sludge too. By increase of dissolved oxygen, SVI decreased and then increased. Value of 1-3 mg/L was the adequate range of dissolved oxygen by settleability of sludge and optimum range was 2-2.5 mg/L. It could be concluded by increasing of dissolved oxygen up to of 3 mg/L, sludge settleability significant decreased.

  5. Canadian municipal carbon trading primer

    International Nuclear Information System (INIS)

    Seskus, A.

    2002-01-01

    The trading of greenhouse gas (GHG) emissions is being suggested as an effective economic way to meet Canada's Kyoto target. Emissions trading is a market-based instrument that can help achieve environmental improvements while using the market to absorb the economical and effective measures to achieve emissions reductions. Placing a value on emissions means that in order to minimize costs, companies will be motivated to apply the lowest-cost emission reductions possible for regulatory approval. The two main types of emissions trading that exist in Canada are the trading of emissions that lead to the formation of smog or acid rain, and the trading of greenhouse gas emissions that lead to climate change. Since carbon dioxide is the most prevalent GHG, making up approximately 75 per cent of Canadian GHG emissions, the trading of units of GHGs is often referred to as carbon trading. The impact that emissions trading will have on municipal operations was the focus of this primer. The trading of GHG involves buying and selling of allowances of GHGs between contracting parties, usually between one party that is short of GHG credits and another that has excess credits. The 3 common approaches to emissions trading include allowance trading (cap and trade), credit trading (baseline and credit), and a hybrid system which combines both credit and allowance trading systems. The issues that impact municipalities include the debate regarding who owns the credits from landfills, particularly if power is generated using landfill gas and the power is sold as green power. Other viable questions were also addressed, including who can claim emission reduction credits if a city implements energy efficiency projects, or fuel substitution programs. Also, will municipalities be allowed to trade internationally, for example, with municipalities in the United States, and how should they spend their money earned from selling credits. This report also presents highlights from 3 emissions

  6. Agricultural yields of irradiated sewage sludge

    International Nuclear Information System (INIS)

    Magnavacca, Cecilia; Miranda, E.; Sanchez, M.

    1999-01-01

    Lettuce, radish and ryegrass have been used to study the nitrogen fertilization of soil by sewage sludge. The results show that the irradiated sludge improve by 15 - 30 % the production yield, compared to the non-irradiated sludge. (author)

  7. Sewage sludge irradiation with electrons

    International Nuclear Information System (INIS)

    Tauber, M.

    1976-01-01

    The disinfection of sewage sludge by irradiation has been discussed very intensively in the last few months. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. AEG-Telefunken is building an irradiation plant with a 1.5 MeV, 25 mA electron accelerator, to study the main features of electron irradiation of sewage sludge. (author)

  8. Mercury emission monitoring on municipal waste combustion

    International Nuclear Information System (INIS)

    Braun, H.; Gerig, A.

    1991-01-01

    In waste incineration, mercury is the only heavy metal to be released as a gas, mostly as mercury(II) chloride, because of its high volatility. Continuous emission monitoring is possible only when mercury occurs in its elemental form. This paper reports on various possibilities of converting Hg(II) into Hg(0) that has been studied and tested on a laboratory scale and in the TAMARA refuse incineration pilot facility. Continuous mercury emission measurement appears to be possible, provided mercury is converted in the flue gas condensate precipitated. The measuring results obtained on two municipal solid waste and on one sewage treatment sludge incineration plants show that the mercury monitor is a highly sensitive and selective continuously working instrument for mercury emission monitoring

  9. Agricultural use of municipal wastewater treatment plant ...

    Science.gov (United States)

    Agricultural use of municipal wastewater treatment plant sewage sludge as a source of per- and polyfluoroalkyl substance (PFAS) contamination in the environment The National Exposure Research Laboratory (NERL) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA mission to protect human health and the environment. HEASD research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EPA strategic plan. More specifically, our division conducts research to characterize the movement of pollutants from the source to contact with humans. Our multidisciplinary research program produces Methods, Measurements, and Models to identify relationships between and characterize processes that link source emissions, environmental concentrations, human exposures, and target-tissue dose. The impact of these tools is improved regulatory programs and policies for EPA.

  10. Comparative study of the methods used for treatment and final disposal of sewage sludge in European countries.

    Science.gov (United States)

    Kelessidis, Alexandros; Stasinakis, Athanasios S

    2012-06-01

    Municipal wastewater treatment results to the production of large quantities of sewage sludge, which requires proper and environmentally accepted management before final disposal. In European Union, sludge management remains an open and challenging issue for the Member States as the relative European legislation is fragmentary and quite old, while the published data concerning sludge treatment and disposal in different European countries are often incomplete and inhomogeneous. The main objective of the current study was to outline the current situation and discuss future perspectives for sludge treatment and disposal in EU countries. According to the results, specific sludge production is differentiated significantly between European countries, ranging from 0.1 kg per population equivalent (p.e.) and year (Malta) to 30.8 kg per p.e. and year (Austria). More stringent legislations comparing to European Directive 86/278/EC have been adopted for sludge disposal in soil by several European countries, setting lower limit values for heavy metals as well as limit values for pathogens and organic micropollutants. A great variety of sludge treatment technologies are used in EU countries, while differences are observed between Member States. Anaerobic and aerobic digestion seems to be the most popular stabilization methods, applying in 24 and 20 countries, respectively. Mechanical sludge dewatering is preferred comparing to the use of drying beds, while thermal drying is mainly applied in EU-15 countries (old Member States) and especially in Germany, Italy, France and UK. Regarding sludge final disposal, sludge reuse (including direct agricultural application and composting) seems to be the predominant choice for sludge management in EU-15 (53% of produced sludge), following by incineration (21% of produced sludge). On the other hand, the most common disposal method in EU-12 countries (new Member States that joined EU after 2004) is still landfilling. Due to the obligations

  11. Sewage sludge additive

    Science.gov (United States)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  12. Composting of sewage sludge irradiated

    International Nuclear Information System (INIS)

    Hashimoto, Shoji; Watanabe, Hiromasa; Nishimura, Koichi; Kawakami, Waichiro

    1981-01-01

    Recently, the development of the techniques to return sewage sludge to forests and farm lands has been actively made, but it is necessary to assure its hygienic condition lest the sludge is contaminated by pathogenic bacteria. The research to treat sewage sludge by irradiation and utilize it as fertilizer or soil-improving material has been carried out from early on in Europe and America. The effects of the irradiation of sludge are sterilization, to kill parasites and their eggs, the inactivation of weed seeds and the improvement of dehydration. In Japan, agriculture is carried out in the vicinity of cities, therefore it is not realistic to use irradiated sludge for farm lands as it is. The composting treatment of sludge by aerobic fermentation is noticed to eliminate the harms when the sludge is returned to forests and farm lands. It is desirable to treat sludge as quickly as possible from the standpoint of sewage treatment, accordingly, the speed of composting is a problem. The isothermal fermentation experiment on irradiated sludge was carried out using a small-scale fermentation tank and strictly controlling fermentation conditions, and the effects of various factors on the fermentation speed were studied. The experimental setup and method are described. The speed of composting reached the maximum at 50 deg C and at neutral or weak alkaline pH. The speed increased with the increase of irradiation dose up to 30 Mrad. (Kako, I.)

  13. Radioactive contamination of sewage sludge

    International Nuclear Information System (INIS)

    Soeder, C.J.; Zanders, E.; Raphael, T.

    1986-01-01

    Because of the radioactivity released through the explosion of the nuclear reactor near Chernobyl radionuclides have been accumulated to a significant extent in sewage sludge in the Federal Republic of Germany. This is demonstrated for samples from four activated sludge plants according to a recent recommendation of the German Commission for Radiation Protection, there is until now no reason to deviate from the common practices of sludge disposal or incineration. The degree of radioactive contamination of plant materials produced on farm lands on which sewage sludge is being spread cannot be estimated with sufficient certainty yet. Additional information is required. (orig.) [de

  14. Sewage sludge disposal in Austria

    International Nuclear Information System (INIS)

    Koch, F.

    1997-01-01

    Sewage systems serve about 70% of the Austrian population, producing 6 million m 3 of sewage sludge per year with a dry matter content of 4-5%. At present about 52% of this sludge is disposed of in land fills, 33% is incinerated, and only about 15 % is used in agriculture. Although agricultural utilization is becoming increasingly important, several problems, especially those related to public opinion, need to be resolved before increased use will be possible. In this paper, wastewater treatment and sewage-sludge production in Austria, and problems associated with sludge disposal are discussed. (author)

  15. Dewatering properties of differently treated sewage sludge

    International Nuclear Information System (INIS)

    Zehnder, H.J.

    1977-01-01

    A study on dewatering properties of radiosterilized sewage sludge of different type and origin was carried out. For comparison, also heat-treated (pasteurized) sludge was investigated. The specific filtration resistance of irradiated sewage sludge was lowered in all types of sludge examined. In general, pasteurization increased this parameter. The settling properties of irradiated digested sewage sludge was slightly improved, mainly in the first hours after treatment. Microbial effects may mask the real sedimentation relations especcially in aerobically stabilized sludges. A pasteurization treatment of sewage sludge caused an increased content of soluble substances and suspended particles in the supernatant water. The supernatant water from irradiated sludge showed a smaller increase

  16. STABILIZATION OF DEWATERED SEWAGE SLUDGE BY AEROBIC COMPOSTING METHOD: USING SAWDUST AS BULKING AGENTS

    Directory of Open Access Journals (Sweden)

    A PARVARESH

    2002-12-01

    Full Text Available Introduction. Sludge production from municipal wastewater treatment plants should have quality standards before disposal in to the environment. Environmental specialists classified sewage sludge as a hazardous waste because of high organic compounds and pathogenic microorganisms. They belive that sewage should be stabilized before disposal and so composting of sewage sludge is an effective and economical method to stabilize. Sewage sludge compost could be used to improve soil structure and enrich the soil with nutrients. Methods. To evaluate the optimum conditions of aerobic compost, the mixture of dewatered sewage sludge from Isfahan municipal waste water treatment plant and sawdust as bulking agent were used. Pilot scale study were performed in Isfahan municipal waste water treatment plant. To perform this research project, the dewatered sewage sludge with humidity between 78 to 82 percent were mixed with sawdust. Turning over method of the piles with one week interval were applied to aerate the mixture. Temperature of the piles were monitored at different depths daily. Other parameters such as N, G, organic matters and pH were determined weekly. Total and fecal coli form, and salmonella were determined at the beginning and end of the composting process, also heavy metals were measured at the same time. Results. The results of this study showed that after days, temperature of the mixture reached up to 55 G, and were stabled for 15 days. Humidity, organic matter, organic carbon and GIN ratio of the mixture decreased over the period of the study, due to increasing the temperature. Also organic matter and humidity mainly decreased in thermofilic phase. The number of total and fecal coliform and also salmonella decreased to A class standards of US.EPA at the end of the operation. Discussion. The results of the study also showed that, this type of composting method is reliable, and simple to schedule, with high flexibility and low odor

  17. Esco in Danish municipalities

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Hansen, Jesper Rohr; Nielsen, Susanne Balslev

    2011-01-01

    Purpose: The aim of this paper is to discuss the possible benefits of involving Energy Service Companies (ESCO) in realising energy savings in municipalities, and how ESCO projects can be formulated very differently in the various municipalities, according to building volume, use of technologies...... municipalities see an in-house approach as a better alternative. Approach (Theory/Methodology): Our research is based on literature studies and on qualitative interviews with Danish municipalities carrying out ESCO projects, as well as with ESCO providers. Results: Our studies suggest that different ESCO......, with relatively few buildings, energy retrofitting and low investments, the integrative and strategic approach include a higher degree of partnership, a more ambitious building renovation approach, and more innovative understandings of facilities management. We also compare ESCO with energy retrofitting as an in...

  18. Municipal Building Energy Usage

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This data set contains energy use data from 2009-2014 for 139 municipally operated buildings. Metrics include: Site & Source EUI, annual electricity, natural...

  19. Intensification of anaerobic digestion efficiency with use of mechanical excess sludge disintegration in the context of increased energy production in wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Żubrowska-Sudoł Monika

    2017-01-01

    Full Text Available The main goal of the study was to evaluate the effects of mechanical sludge disintegration for enhancing full scale anaerobic digestion of municipal sludge. Batch disintegration tests and lab dewatering tests were also performed aiming at determining the release of organic compounds and assessing the impact of disintegration of excess sludge before the fermentation process of mixed sludge on the dewaterability of post-fermented sludge, respectively. In the study a disc disintegrator driven by a motor with a power of 30 kW, revolutions n = 2950 rpm has been used. It was shown that with increase of energy consumed in the disintegration, the increased amounts of organic compounds were released from the sludge. It was also documented that the introduction of the excess sludge disintegration prior to fermentation tank, resulted in a significant increase in biogas production (by an average of 33.9% and in increase in volatile total solids reduction in the fermented sludge (by an average of 22.7%. Moreover, the obtained results indicate the possibility of obtaining a higher degree of sludge dewatering, which was subjected to anaerobic stabilization with using disintegrated excess sludge.

  20. Intensification of anaerobic digestion efficiency with use of mechanical excess sludge disintegration in the context of increased energy production in wastewater treatment plants

    Science.gov (United States)

    Żubrowska-Sudoł, Monika; Podedworna, Jolanta; Bisak, Agnieszka; Sytek-Szmeichel, Katarzyna; Krawczyk, Piotr; Garlicka, Agnieszka

    2017-11-01

    The main goal of the study was to evaluate the effects of mechanical sludge disintegration for enhancing full scale anaerobic digestion of municipal sludge. Batch disintegration tests and lab dewatering tests were also performed aiming at determining the release of organic compounds and assessing the impact of disintegration of excess sludge before the fermentation process of mixed sludge on the dewaterability of post-fermented sludge, respectively. In the study a disc disintegrator driven by a motor with a power of 30 kW, revolutions n = 2950 rpm has been used. It was shown that with increase of energy consumed in the disintegration, the increased amounts of organic compounds were released from the sludge. It was also documented that the introduction of the excess sludge disintegration prior to fermentation tank, resulted in a significant increase in biogas production (by an average of 33.9%) and in increase in volatile total solids reduction in the fermented sludge (by an average of 22.7%). Moreover, the obtained results indicate the possibility of obtaining a higher degree of sludge dewatering, which was subjected to anaerobic stabilization with using disintegrated excess sludge.

  1. Hybrid life-cycle environmental and cost inventory of sewage sludge treatment and end-use scenarios: a case study from China.

    Science.gov (United States)

    Murray, Ashley; Horvath, Arpad; Nelson, Kara L

    2008-05-01

    Sewage sludge management poses environmental, economic, and political challenges for wastewater treatment plants and municipalities around the globe. To facilitate more informed and sustainable decision making, this study used life-cycle inventory (LCI) to expand upon previous process-based LCIs of sewage sludge treatmenttechnologies. Additionally, the study evaluated an array of productive end-use options for treated sewage sludge, such as fertilizer and as an input into construction materials, to determine how the sustainability of traditional manufacturing processes changes with sludge as a replacement for other raw inputs. The inclusion of the life-cycle of necessary inputs (such as lime) used in sludge treatment significantly impacts the sustainability profiles of different treatment and end-use schemes. Overall, anaerobic digestion is generally the optimal treatment technology whereas incineration, particularly if coal-fired, is the most environmentally and economically costly. With respect to sludge end use, offsets are greatest for the use of sludge as fertilizer, but all of the productive uses of sludge can improve the sustainability of conventional manufacturing practices. The results are intended to help inform and guide decisions about sludge handling for existing wastewater treatment plants and those that are still in the planning phase in cities around the world. Although additional factors must be considered when selecting a sludge treatment and end-use scheme, this study highlights how a systems approach to planning can contribute significantly to improving overall environmental sustainability.

  2. Mechanical and Physical Properties of Hydrophobized Lightweight Aggregate Concrete with Sewage Sludge.

    Science.gov (United States)

    Suchorab, Zbigniew; Barnat-Hunek, Danuta; Franus, Małgorzata; Łagód, Grzegorz

    2016-04-27

    This article is focused on lightweight aggregate-concrete modified by municipal sewage sludge and lightweight aggregate-concrete obtained from light aggregates. The article presents laboratory examinations of material physical parameters. Water absorptivity of the examined material was decreased by the admixture of water emulsion of reactive polysiloxanes. Water transport properties were determined using Time Domain Reflectometry, an indirect technique for moisture detection in porous media. Together with basic physical parameters, the heat conductivity coefficient λ was determined for both types of lightweight aggregate-concrete. Analysis of moisture and heat properties of the examined materials confirmed the usefulness of light aggregates supplemented with sewage sludge for prospective production.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-02-15

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

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

    International Nuclear Information System (INIS)

    Kliopova, Irina; Makarskienė, Kristina

    2015-01-01

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

  5. Analysis of Pharmaceutical and Personal Care Compounds in Wastewater Sludge and Aqueous Samples using GC-MS/MS

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Lirong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitroshkov, Alexandre V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gilmore, Tyler J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-03-15

    The Bioenergy Program at Pacific Northwest National Laboratory (PNNL) is evaluating the feasibility of converting wastewater sludge materials to fuels. Wastewater sludge from various municipalities will be used in the evaluation process and as with any municipal waste, there is the potential for residual contaminates to remain in the sludge following wastewater treatment. Many surveys and studies have confirmed the presence of pharmaceuticals in municipal wastewater and effluents (World Health Organization, 2011). Determination of the presence and concentrations of the contaminants is required to define the proper handling of this sludge. A list of targeted compounds was acquired from the literature and an analytical method was developed for the pharmaceutical and personal care compounds. The presence of organics complicated the analytical techniques and, in some cases, the precision of the results. However, residual concentrations of a range of compounds were detected in the wastewater sludge and the presence and concentrations of these compounds will be considered in identifying the appropriate handling of this material in conduct of research.

  6. Application of Sludges and Wastewaters on Agricultural Land: A Planning and Educational Guide, MCD-35. Research Bulletin 1090.

    Science.gov (United States)

    Knezek, Bernard D., Ed.; Miller, Robert H., Ed.

    This report addresses the application of agricultural processing wastes, industrial and municipal wastes on agricultural land as both a waste management and resource recovery and reuse practice. The document emphasizes the treatment and beneficial utilization of sludge and wastewater as opposed to waste disposal. These objectives are achieved…

  7. Sewage sludge utilisation and disposal alternatives and their comparison; Puhdistamolietteiden hyoedyntaemis- ja loppusijoitusvaihtoehdot sekae niiden vertailu

    Energy Technology Data Exchange (ETDEWEB)

    Paatero, P.

    2001-07-01

    Sludge production will presumably not decrease in future. At present agricultural use of sludge is unstable and landfilling will most probably be restricted in the following years. The objective of this thesis is to gather information on options for sludge treatment and utilisation and to compare these options in order to find the best possible solution for future alternatives of sludge utilisation. Finnish and international literature as well as Finnish and EU legislation have been reviewed. Furthermore the mentoring group of this thesis as well as other experts in Finland have been used as a source of information. Sludge contains not only plant nutrients and organic matter but also varying quantities of a number of more or less hazardous substances. The quality and quantity of sewage sludge are described and possible health and environmental risks caused by sewage sludge are pointed out. The legislation linked to sludge utilisation and its demands are also presented. The sludge processing methods reviewed are: thickening, lime stabilisation, aerobic digestion, anaerobic digestion, composting and mechanical and thermal drying. In addition, the positive and negative sides of the stabilisation processes are looked at in greater detail. Agricultural use, landscaping, forestry, landfill, incineration, sludge derived products and newer processing technologies are reviewed as sludge utilisation options. Their environmental impacts, positive and negative sides and practical feasibility are evaluated. Various treatment utilisation combinations are also compared. Furthermore a rough cost assessment is presented. The optimal utilisation alternative has to be chosen case by case. The best use of plant nutrients and valuable organic matter is obtained in agricultural use or in landscaping. In the present situation it is difficult to enhance the portion of agricultural use, and landscaping is restricted by a low demand on the market. Incineration is an expensive option and can

  8. Sludge Digestion Manual; Handboek Slibgisting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-15

    This manual offers a guideline for developing, designing, optimizing and operating sludge digestion installations based on sewage sludge. It also offers tools for solving operation problems [Dutch] Het Handboek is een leidraad voor het ontwikkelen, ontwerpen, optimaliseren en bedrijven van slibgistingsinstallaties voor zuiveringsslib. Ook geeft het handvatten voor het oplossen van operationele problemen.

  9. Representative of the municipality

    International Nuclear Information System (INIS)

    Castellnou Barcelo, J.

    2007-01-01

    Full text of publication follows. The decommissioning of the Vandellos-I nuclear power plant was a big challenge for the host community of Vandellos i l'Hospitalet de l'Infant and the close-by region. Closing down of the facility resulted in a rise of unemployment and a decrease of municipal income. The public was concerned with three issues: safety, transparency and information about the decommissioning, and economic future. Therefore, from the very beginning, municipal governments entered into negotiations with ENRESA on socio-economic benefits, including local employment in dismantling activities, and other types of financial and non-financial compensation. The ADE business association, i.e. a network of business organisations was created that guided the allotment of work to local firms. To satisfy public demand, local municipalities focused on the triad of safety, dialogue and local development, considered the three 'pillars of trust'. A Municipal Monitoring Commission was created, made up of representatives of affected municipalities, the regional government, the ADE business association, trade unions, the local university, the NPP management and ENRESA to monitor the dismantling process and regularly inform the local public. Items that were handled by this Commission included: - Work process monitoring. - Workers. - Materials Control. - Conventional and radioactive or contaminated waste management. - Emanation waste management (liquid and gas) - Safety (training and accidents). - Surveillance (radiological and environmental: dust, noise). - Effects. - Fulfillment of agreed conditions. A number of communication tools and channels were used, e.g., public information meetings, an information centre, the municipal magazine, the municipal radio station, and meetings with representatives of the local press. Particularly innovative was the idea to ask academics from the University of Tarragona to help with 'translating' technical information into language that could

  10. Descentralização e endividamento municipal: formas, limites e possibilidades Decentralization and municipal indebtedness: modes, constraints, and possibilities

    Directory of Open Access Journals (Sweden)

    Amaury Patrick Gremaud

    2002-01-01

    Full Text Available The objective of this article is to discuss alternatives to finance investments by municipalities. In general, current revenues are insufficient to finance large investments, what brings about the necessity of municipal indebtedness. These could assume different manners, according to the nature of the investment: if it is typically public or if it offers private return. For the first case, we discuss the possibilities of a municipal bond market and, for the second, we discuss project finance and the participation of the private sector.

  11. Ultrasonic sludge pretreatment under pressure.

    Science.gov (United States)

    Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri

    2013-09-01

    The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Lipid profiling in sewage sludge.

    Science.gov (United States)

    Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

    2017-06-01

    High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effects of sewage sludge on Di-(2-ethylhexyl) phthalate uptake by plants

    International Nuclear Information System (INIS)

    Aranda, J.M.; O'Connor, G.A.; Eiceman, G.A.

    1989-01-01

    Di-(2-ethylhexyl) phthalate (DEHP) is a priority organic pollutant frequently found in municipal sludges. A greenhouse study was conducted to determine the effect of sludge on plant uptake of 14 C-DEHP (carbonyl labeled). Plants grown included three food chain crops, lettuce (Lactuca sativa L.), carrot (Daucus carota L.) and chile pepper (Capsicum annuum L.) and tall fescue (Festuca arundinacea Schreb.). Net 14 C concentration in plants grown in soil amended with 14 C-DEHP-contaminated sludge was independent of sludge rate (at the same DEHP loading) for lettuce, chile fruit, and carrot roots. Net 14 C concentration, however, was inversely related to sludge rate in carrot tops, fescue, and chile plants. Intact DEHP was not detected in plants by gas chromatography/mass spectrometry analysis. Calculated plant DEHP concentrations (based on measured net 14 C concentrations and DEHP specific activities) were generally correlated better with DEHP soil solution concentrations than with total DEHP soil concentrations. Net 14 C-DEHP bioconcentration factors were calculated from initial soil DEHP concentration and plant fresh weights. Bioconcentration factors ranged from 0.01 to 0.03 for fescue, lettuce, carrots, and chile, suggesting little DEHP uptake. Additionally, because intact DEHP was not detected in any plants, DEHP uptake by plants was of minor importance and would not limit sludge additions to soils used to grow these crops

  14. Environmental and plant effects of sewage sludge application to forests and pastures

    International Nuclear Information System (INIS)

    Van Miegroet, H.; Boston, H.L.; Johnson, D.W.; Nevada Univ., Reno, NV

    1989-01-01

    Digested sewage sludge was applied to pastures and tree plantations at 19 to 44 Mg/ha (dry weight) as part of a municipal sludge disposal program. The sludge had low concentrations of heavy metals and traces of 137 Cs and 60 Co. Monitoring of soils, soil solutions, and runoff indicated that N, P, heavy metals, and radionuclides were largely retained in the upper 15cm of the soil. Soil solutions had elevated NO 3 - concentrations often >100 mg/L, but no significant increases in groundwater NO 3 - were found during the first year. Runoff from active sites had elevated concentrations of NO 3 - (20--30 mg/L), soluble P (1 mg/L), BOD 5 (5--30 mg/L), and fecal coliform (up to 14,000 colonies per 100 ml), not unlike runoff from pastures with cattle. Enrichment of organic N (2 times), available (inorganic) N (5 to 10 times), and Bray-P in the upper soils persisted for several years following sludge application. Sludge increased vegetation N concentrations from 1.5% to 2.3% and P concentrations from 0.16% to 0.31%. With the exception of Zn, heavy metals did not accumulate substantially in the vegetation. The sludge addition increased the survival and growth of sycamore (Platanus occidentalis L.). For a loblolly pine (Pinus taeda L.) plantation future growth improvements are expected based on elevated foliar N concentrations. 37 refs., 3 figs., 7 tabs

  15. [Harvest of the carbon source in wastewater by the adsorption and desorption of activated sludge].

    Science.gov (United States)

    Liu, Hong-Bo; Wen, Xiang-Hua; Zhao, Fang; Mei, Yi-Jun

    2011-04-01

    The carbon source in municipal wastewater was adsorbed by activated sludge and then harvested through the hydrolysis of activated sludge. Results indicated that activated sludge had high absorbing ability towards organic carbon and phosphorus under continuous operation mode, and the average COD and TP absorption rate reached as high as 63% and 76%, respectively. Moreover, about 50% of the soluble carbon source was outside of the sludge cell and could be released under mild hydrolysis condition. Whereas the absorbed amount of nitrogen was relatively low, and the removal rate of ammonia was only 13% . Furthermore, the releases of organic carbon, nitrogen and phosphorus from the sludge absorbing pollutants in the wastewater were studied. By comparing different hydrolysis conditions of normal (pH 7.5, 20 degrees C), heating (pH 7.5, 60 degrees C) and the alkaline heating (pH 11, 60 degrees C), the last one presented the optimum hydrolysis efficiency. Under which, the release rate of COD could reach 320 mg/g after 24 hours, whereas nitrogen and phosphorus just obtained low release rates of 18 mg/g and 2 mg/g, respectively. Results indicate that the carbon source in wastewater could be harvested by the adsorption and desorption of activated sludge, and the concentrations of nitrogen and phosphorus are low and would not influence the reuse of the harvested carbon source.

  16. Comparison of some characteristics of aerobic granules and sludge flocs from sequencing batch reactors.

    Science.gov (United States)

    Li, J; Garny, K; Neu, T; He, M; Lindenblatt, C; Horn, H

    2007-01-01

    Physical, chemical and biological characteristics were investigated for aerobic granules and sludge flocs from three laboratory-scale sequencing batch reactors (SBRs). One reactor was operated as normal SBR (N-SBR) and two reactors were operated as granular SBRs (G-SBR1 and G-SBR2). G-SBR1 was inoculated with activated sludge and G-SBR2 with granules from the municipal wastewater plant in Garching (Germany). The following major parameters and functions were measured and compared between the three reactors: morphology, settling velocity, specific gravity (SG), sludge volume index (SVI), specific oxygen uptake rate (SOUR), distribution of the volume fraction of extracellular polymeric substances (EPS) and bacteria, organic carbon and nitrogen removal. Compared with sludge flocs, granular sludge had excellent settling properties, good solid-liquid separation, high biomass concentration, simultaneous nitrification and denitrification. Aerobic granular sludge does not have a higher microbial activity and there are some problems including higher effluent suspended solids, lower ratio of VSS/SS and no nitrification at the beginning of cultivation. Measurement with CLSM and additional image analysis showed that EPS glycoconjugates build one main fraction inside the granules. The aerobic granules from G-SBR1 prove to be heavier, smaller and have a higher microbial activity compared with G-SBR2. Furthermore, the granules were more compact, with lower SVI and less filamentous bacteria.

  17. Two step esterification-transesterification process of wet greasy sewage sludge for biodiesel production.

    Science.gov (United States)

    Urrutia, C; Sangaletti-Gerhard, N; Cea, M; Suazo, A; Aliberti, A; Navia, R

    2016-01-01

    Sewage sludge generated in municipal wastewater treatment plants was used as a feedstock for biodiesel production via esterification/transesterification in a two-step process. In the first esterification step, greasy and secondary sludge were tested using acid and enzymatic catalysts. The results indicate that both catalysts performed the esterification of free fatty acids (FFA) simultaneously with the transesterification of triacylglycerols (TAG). Acid catalyst demonstrated better performance in FFA esterification compared to TAG transesterification, while enzymatic catalyst showed the ability to first hydrolyze TAG in FFA, which were esterified to methyl esters. In addition, FAME concentration using greasy sludge were higher (63.9% and 58.7%), compared with those of secondary sludge (11% and 16%), using acid and enzymatic catalysts, respectively. Therefore, only greasy sludge was used in the second step of alkaline transesterification. The alkaline transesterification of the previously esterified greasy sludge reached a maximum FAME concentration of 65.4% when using acid catalyst. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. SEWAGE SLUDGE AS AN INGREDIENT IN FERTILIZERS AND SOIL SUBSTITUTES

    Directory of Open Access Journals (Sweden)

    Anna Grobelak

    2016-06-01

    Full Text Available In Poland, sludge management especially in medium and small sewage treatment plants is still a significant problem. According to data from the Central Statistical Office and the report on the implementation of the National Urban Wastewater Treatment Program (in polish KPOŚK land application of sewage sludge remains one of the main methods, although there has been considerable interest known: 'application for other purposes ", where the preparation of composts and fertilizers is included. The use of fertilizer produced from sewage sludge (compost, granules, organic and mineral fertilizers, is regulated by the Act on fertilizers and fertilization, and the relevant implementing rules. For example, they define the test procedure (concerning the quality of fertilizers to enable appropriate permissions to market this type of fertilizers. There is still only several technologies existing on the Polish market dedicated to production of fertilizers in advanced technologies of sewage sludge treatment. Usually the treatment plants are trying to obtain the necessary certificates for generated fertilizers (including composts, or soils substitutes. The advantages of these technologies should be no doubt: the loss of waste status, ability to store the fertilizer and unlimited transportation between areas, sanitization of the product (as a result of the use of calcium or sulfur compounds or temperature should be an alternative for drying technology. While the disadvantages are primarily the investment costs and time consuming certification procedures. However, these solutions enable to maintain the organic matter and phosphorus as well as greater control over possible pollution introduced into the soil.

  19. Sewage sludge pasteurization by gamma radiation: A Canadian demonstration project — 1988-91

    Science.gov (United States)

    Swinwood, Jean F.; Wilson, Bruce K.

    Nordion International Inc. and a Canadian city, in cooperation with the Federal & Provincial Ministries of the Environment, began a project in 1988 to construct and operate a commercial-scale sewage sludge pasteurization facility using gamma radiation technology. The facility is scheduled to begin operations in 1991. This paper discusses the objectives and scope of the project, the design of the irradiation system, and the plans to market the pasteurized sludge as a high-value, organic soil conditioner and fertilizer.

  20. Treatment of radioactive sludge

    International Nuclear Information System (INIS)

    Allison, W.; Payne, B.J.; Pegler, G.E.

    1979-01-01

    Radioactive sludge e.g. that which may accumulate in irradiated nuclear fuel element storage ponds, is treated by pumping it from a settling tank to a particle separator, conveniently a hydrocyclone and a sloping plate separator, the liquid being returned to the settling tank and the solids being metered into a drum pre-lined with dry cement. The drums are in a containment box in which they are transferred to a mixing station where the particles and cement are mixed and thence to a curing station. After curing the drums are embedded in cement in outer containers for transport to a long-term storage site. (author)

  1. Anaerobic codigestion of municipal, farm, and industrial organic wastes: a survey of recent literature.

    Science.gov (United States)

    Alatriste-Mondragón, Felipe; Samar, Parviz; Cox, Huub H J; Ahring, Birgitte K; Iranpour, Reza

    2006-06-01

    Codigestion of organic wastes is a technology that is increasingly being applied for simultaneous treatment of several solid and liquid organic wastes. The main advantages of this technology are improved methane yield because of the supply of additional nutrients from the codigestates and more efficient use of equipment and cost-sharing by processing multiple waste streams in a single facility. Many municipal wastewater treatment plants (WWTPs) in industrialized countries currently process wastewater sludge in large digesters. Codigestion of organic wastes with municipal wastewater sludge can increase digester gas production and provide savings in the overall energy costs of plant operations. Methane recovery also helps to reduce the emission of greenhouse gases to the atmosphere. The goal of this literature survey was to summarize the research conducted in the last four years on anaerobic codigestion to identify applications of codigestion at WWTPs. Because the solids content in municipal wastewater sludge is low, this survey only focuses on codigestion processes operated at relative low solids content (slurry mode). Semi-solid or solid codigestion processes were not included. Municipal wastewater sludge, the organic fraction of municipal solid waste, and cattle manure (CAM) are the main wastes most often used in codigestion processes. Wastes that are codigested with these main wastes are wood wastes, industrial organic wastes, and farm wastes. These are referred to in this survey as codigestates. The literature provides many laboratory studies (batch assays and bench-scale digesters) that assess the digestibility of codigestates and evaluate the performance and monitoring of codigestion, inhibition of digestion by codigestates, the design of the process (e.g., single-stage or two-stage processes), and the operation temperature (e.g., mesophilic or thermophilic). Only a few reports on pilot- and full-scale studies were found. These evaluate general process

  2. Physical and chemical factors affecting sludge consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Turner, C.W.; Blimkie, M.E.; Lavoie, P.A

    1997-09-01

    Chemical reactions between sludge components and precipitation reactions within the pores of the existing sludge are shown to contribute to the consolidation of sludge under steam generator operating conditions. Simulations of sludge representative of plants with a mixed iron/copper feedtrain suggest that as the conditions in the feedtrain become more oxidizing the sludge will become harder with a higher nickel ferrite content. The precipitation of feedwater impurities introduced by condenser leaks and of zinc silicate, which is produced in plants with brass condenser tubes and silica in the makeup water, contribute significantly to sludge consolidation. Sodium phosphate is also shown to be an agent of sludge consolidation. (author)

  3. Characterization of fluoroquinolone resistance and qnr diversity in Enterobacteriaceae from municipal biosolids.

    Directory of Open Access Journals (Sweden)

    Ella eKaplan

    2013-06-01

    Full Text Available Municipal biosolids produced during activated sludge treatment applied in waste water treatment plants, are significant reservoirs of antibiotic resistance, since they assemble both natural and fecal microbiota, as well as residual concentrations of antibiotic compounds. This raises major concerns regarding the environmental and epidemiological consequences of using them as fertilizers for crops. The second generation fluoroquinolone ciprofloxacin is probably the most abundant antibiotic compound detected in municipal biosolids due to its widespread use and sorption properties. Although fluoroquinolone resistance was originally thought to result from mutations in bacterial gyrase and topoisomerase IV genes, it is becoming apparent that it is also attributed to plasmid-associated resistance factors, which may propagate environmental antibiotic resistance. The objective of this study was to assess the impact of the activated sludge process on fluoroquinolone resistance. The scope of resistances and mobile genetic mechanisms associated with fluoroquinolone resistance were evaluated by screening large collections of ciprofloxacin-resistant Enterobacteriaceae strains from sludge (n=112 and from raw sewage (n=89. Plasmid-mediated quinolone resistance determinants (qnrA, B and S were readily detected in isolates from both environments, the most dominant being qnrS. Interestingly, all qnr variants were significantly more abundant in sludge isolates than in the isolates from raw sewage. Almost all of ciprofloxacin-resistant isolates were resistant to multiple antibiotic compounds. The sludge isolates were on the whole resistant to a broader range of antibiotic compounds than the raw sewage isolates; however this difference was not statistically significant. Collectively, this study indicates that the activated sludge selects for multiresistant bacterial strains, and that mobile quinolone-resistance elements may have a selective advantage in the activated

  4. ESCO in Danish municipalities

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Hansen, Jesper Rohr; Nielsen, Susanne Balslev

    2013-01-01

    development with international ESCO experience as well as refer to public innovation literature. Combined with empirical case studies on ESCO contracting, we discuss factors and conditions that influence decisions on ESCO, the flexibility of ESCO contracts and whether it implies an innovative process...... mainly been used in the industry so far, but in recent years more and more municipalities have taken up ESCO initiatives, in order to retrofit existing public buildings, and to make them more energy efficient. ESCO is in many ways a new way of collaboration for Danish municipalities, and therefore...... in municipalities ESCOs have received much attention in different Danish energy-.efficiency policies, where ESCOs are often described as a promising way to achieve energy savings in existing housing and to overcome barriers encountered by other attempts at energy savings. Instead of assessing ESCO only...

  5. Municipal energy managers

    International Nuclear Information System (INIS)

    2004-01-01

    On 1 and 2 July, municipal energy managers from all over Europe met in Stuttgart, Germany. On these two days, more the 150 participants form 22 countries listened to presentations, took part in excursions to cutting-edge energy conservation projects in Stuttgart and, above all, participated in a broad array of workshops presented by experts firmly grounded in local practice. 27 experts drawn from 11 European countries showcased their projects and imparted their experience. The event has been accompanied by an exhibition of companies and service providers offering energy-conservation products and planning services. The first workshop dealt with energy management in Europe and examples from different active municipalities; the second one with energy management in Germany and best practice in the leading cities; the third one with non-municipal and European projects. (A.L.B.)

  6. Market scope

    International Nuclear Information System (INIS)

    2002-01-01

    Nova Scotia's Energy Strategy is aimed at opening the electricity market to wholesale competition, allowing eligible wholesale customers (such as municipal distribution utilities) to buy their electricity from competitive sources. The Nova Scotia Electricity Marketplace Governance Committee (EMGC) is concerned that this will not promote long-term competition because these eligible customers form only a very small fraction (1.6 per cent) of the total electricity demand in the province. This report examines the possible extensions of competition beyond the minimum specified in the Energy Strategy. It also identifies approaches that the EMGC may consider, including other potential levels of competition and their associated issues. The report discussed the issue of implementing wholesale competition as it relates to unbundling of the transmission tariff from the cost of energy supply and from the cost of distribution in retail marketing. The stages of expanding the market scope were also described with reference to large industrial customers, medium industrial and large commercial customers, and small commercial and residential customers. The report states that it is unlikely that the transition to an open access transmission market will need to be reversed, as it is likely to be an essential component of any further development. The EMGC feels it could minimize future transition costs and promote future evolution of competition by recommending for an institutional and market structure that is compatible with a broader competitive market

  7. The impact of sewage sludge treatment on the content of selected heavy metals and their fractions.

    Science.gov (United States)

    Ignatowicz, Katarzyna

    2017-07-01

    The aim of the study was to assess the physicochemical properties of compost made of municipal sewage sludge from selected Municipal Sewage Treatment Plant. Content of basic macroelements and heavy metals (Zn, Cu, Cr, Cd, Ni, Pb, Hg, Mg, Ca, N, P, K, Na) and their fractions was determined by means of BCR method. Based on the analyzes, it was found that the content of heavy metals in compost did not exceed the limits set by natural land management of sewage sludge; the compost is very abundant in biogenic elements - nitrogen and phosphorus - and it can be also considered a significant source of calcium and magnesium. The analysis of results obtained from the three-stage chemical extraction revealed that deposits subjected to aerobic stabilization and composting accumulate metals (in descending sequence) in fractions III and II, i.e. fractions virtually inaccessible to the ecosystem in optimal conditions of use. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Characterization, Modeling and Application of Aerobic Granular Sludge for Wastewater Treatment

    Science.gov (United States)

    Liu, Xian-Wei; Yu, Han-Qing; Ni, Bing-Jie; Sheng, Guo-Ping

    Recently extensive studies have been carried out to cultivate aerobic granular sludge worldwide, including in China. Aerobic granules, compared with conventional activated sludge flocs, are well known for their regular, dense, and strong microbial structure, good settling ability, high biomass retention, and great ability to withstand shock loadings. Studies have shown that the aerobic granules could be applied for the treatment of low- or high-strength wastewaters, simultaneous removal of organic carbon, nitrogen and phosphorus, and decomposition of toxic wastewaters. Thus, this new form of activate sludge, like anaerobic granular sludge, could be employed for the treatment of municipal and industrial wastewaters in near future. This chapter attempts to provide an up-to-date review on the definition, cultivation, characterization, modeling and application of aerobic granular sludge for biological wastewater treatment. This review outlines some important discoveries with regard to the factors affecting the formation of aerobic granular sludge, their physicochemical characteristics, as well as their microbial structure and diversity. It also summarizes the modeling of aerobic granule formation. Finally, this chapter highlights the applications of aerobic granulation technology in the biological wastewater treatment. It is concluded that the knowledge regarding aerobic granular sludge is far from complete. Although previous studies in this field have undoubtedly improved our understanding on aerobic granular sludge, it is clear that much remains to be learned about the process and that many unanswered questions still remain. One of the challenges appears to be the integration of the existing and growing scientific knowledge base with the observations and applications in practice, which this paper hopes to partially achieve.

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

    Science.gov (United States)

    Kliopova, Irina; Makarskienė, Kristina

    2015-02-01

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

  10. Comparative analysis of the efficiency, reliability, technical feasibility and costs of methods to convert sewage sludge to a hygienically safe condition

    International Nuclear Information System (INIS)

    Fuhrmann, D.; Leschber, R.; Mueller, G.; Jaeger, B.; Neumann, U.

    1981-01-01

    Due to the development of sewage treatment technology and the construction of new and sewage works and enlargement of older ones, increasing amounts of sewage sludge have been produced. Agricultural use of municipal sewage sludge is a practicable way of utilization which, however, is often limited for reasons of hygienic safety. The present study intends to describe methods of sewage sludge disinfection which have been used in practice or tested extensively, as well as technical innovations in this field, and to give information on their performance with respect to hygienic and technical requirements. A direct comparison of processes has turned out to be extremely difficult because disinfection of sewage sludge is only one of the stages of sewage treatment. For comparison, numerous factors have to be taken into account such as plant size, type of sewage and sludge treatment processes, energy costs, sales potential for agricultural use etc. This study is meant as an aid in such work. (orig.) [de

  11. Effect Of Wood-Based Biochar And Sewage Sludge Amendments For Soil Phosphorus Availability

    Directory of Open Access Journals (Sweden)

    Frišták Vladimír

    2015-06-01

    Full Text Available This study investigated the effects of two biochars (pyrolysed wood chips and garden clippings on phosphorus (P availability in a heavy-metal contaminated soil poor in phosphorus. Short-term 14-days incubation experiments were conducted to study how applications of biochars at different rates (1 and 5 % in combination with (1:1 and without dried sewage sludge from a municipal waste water treatment plant (WWTP affected the content of soil extractable P. For P-availability analyses deionized water, calcium acetate lactate (CAL, Mehlich 3 and Olsen extraction protocols were applied. In addition, the content of total and mobile forms of potentially toxic heavy metals (PTHM was studied. Application of both biochars caused a significant decrease of PTHM available forms in sewage sludge amended soil samples. The concentration of total and available P increased with higher biochar and sewage sludge application rates.

  12. Effect of Addition of High Strength Food Wastes on Anaerobic Digestion of Sewage Sludge

    OpenAIRE

    Vaidya, Ramola Vinay

    2015-01-01

    Anaerobic co-digestion of municipal sludge and food wastes high in chemical oxygen demand (COD) has been an area of interest for waste water treatment facilities looking to increase methane production, and at the same time, dispose of the wastes and increase the revenue. However, addition of food wastes containing fats, oils and grease (FOG) to the conventional anaerobic digestion process can be difficult and pose challenges to utilities. Incorporating these wastes into the treatment plants c...

  13. Preliminary results of lab-scale investigations of products of incomplete combustion during incineration of primary and mixed digested sludge.

    Science.gov (United States)

    Braguglia, C M; Bagnuolo, G; Gianico, A; Mininni, G; Pastore, C; Mascolo, G

    2016-03-01

    Separation between primary and secondary sludge treatment could be a valuable solution for sludge management. According to this approach, secondary sludge can be conveniently used in agriculture while primary sludge could be easily dried and incinerated. It follows that some concern may arise from incinerating primary sludge with respect to the current practice to incinerate mixed digested sludge. Incineration of primary and mixed digested municipal sludge was investigated with a lab-scale equipment in terms of emissions of products of incomplete combustion (PICs) during incineration failure modes. PICs can be grouped in three sub-categories, namely aliphatic hydrocarbons (alkanes and alkenes), compounds with a single aromatic ring, and polycyclic aromatic hydrocarbons (PAHs). After-burning temperature was the most important parameter to be controlled in order to minimize emissions of alkanes and alkenes. As for mono-aromatic compounds, benzene and toluene are the most thermally resistant compounds, and in some cases, an after-burning temperature of 1100 °C was not enough to get the complete destruction of benzene leading to a residual emission of 18 mg/kgsludge. PAHs showed an opposite trend with respect to aliphatic and mono-aromatic hydrocarbons being the thermal failure mode the main responsible of PIC emissions. A proper oxygen concentration is more important than elevated temperature thus reflecting the high thermal stability of PAHs. Overall, obtained results, even though obtained under flameless conditions that are different from those of the industrial plants, demonstrated that separation of primary and secondary sludge does not pose any drawbacks or concern regarding primary sludge being disposed of by incineration even though it is more contaminated than mixed digested sludge in terms of organic pollutants.

  14. Sludge pretreatment chemistry evaluation: Enhanced sludge washing separation factors

    International Nuclear Information System (INIS)

    Colton, N.G.

    1995-03-01

    This report presents the work conducted in Fiscal Year 1994 by the Sludge Pretreatment Chemistry Evaluation Subtask for the Tank Waste Remediation System (TWRS) Tank Waste Treatment Science Task. The main purpose of this task, is to provide the technical basis and scientific understanding to support TWRS baseline decisions and actions, such as the development of an enhanced sludge washing process to reduce the volume of waste that will require high-level waste (HLW) vitrification. One objective within the Sludge Pretreatment Chemistry Evaluation Subtask was to establish wash factors for various SST (single-shell tank) sludges. First, analytical data were compiled from existing tank waste characterization reports. These data were summarized on tank-specific worksheets that provided a uniform format for reviewing and comparing data, as well as the means to verify whether the data set for each tank was complete. Worksheets were completed for 27 SST wastes. The analytical water wash data provided tank-specific information about the fraction of each component that dissolves with water, i.e., an estimate of tank-specific wash factors for evaluating tank-by-tank processing. These wash data were then used collectively to evaluate some of the wash factors that are assumed for the overall SST waste inventory; specifically, wash factors for elements that would be found primarily in sludges. The final step in this study was to incorporate the characterization and wash factor data into a spreadsheet that provides insight into the effect of enhanced sludge washing on individual tank sludges as well as for groups of sludges that may be representative of different waste types. Spreadsheet results include the estimated mass and percentage of each element that would be removed with washing and leaching. Furthermore, estimated compositions are given of the final wash and leach streams and residual solids, in terms of both concentration and dry weight percent

  15. Co-conditioning and dewatering of chemical sludge and waste activated sludge.

    Science.gov (United States)

    Chang, G R; Liu, J C; Lee, D J

    2001-03-01

    The conditioning and dewatering behaviors of chemical and waste activated sludges from a tannery were studied. Capillary suction time (CST), specific resistance to filtration (SRF), and bound water content were used to evaluate the sludge dewatering behaviors. Zeta potentials were also measured. Experiments were conducted on each sludge conditioned and dewatered separately, and on the sludge mixed at various ratios. Results indicate that the chemical sludge was relatively difficult to be dewatered, even in the presence of polyelectrolyte. When the waste activated sludge was mixed with the chemical sludge at ratios of 1:1 and 2:1, respectively, the dewaterability of chemical sludge improved remarkably while the relatively better dewaterability of the waste activated sludge deteriorated only to a limited extent. As the mixing ratios became 4:1 and 8:1, the dewaterability of the mixed sludge was equal to that of the waste activated sludge. The optimal polyelectrolyte dosage for the mixed sludge was equal to or less than that of the waste activated sludge. It is proposed that the chemical sludges act as skeleton builders that reduce the compressibility of the mixed sludge whose dewaterability is enhanced. Bound water contents of sludge decreased at low polyelectrolyte dosage and were not significantly affected as polyelectrolyte dosage increased. Advantages and disadvantages of co-conditioning and dewatering chemical sludge and waste activated sludge were discussed.

  16. How efficient are municipalities in activating cash-help recipients in Denmark

    DEFF Research Database (Denmark)

    Weatherall, James; Beltov, Tor

    Previous studies do not analyse activation starts as the parameter of interest in evaluating labour market programs. In this paper we evaluate municipality ability to activate cash-help recipients, which helps recipients gain the necessary skills vital to future regular employment in Denmark...... policy (ALMP) practices and organisation can only determine activation participation to a certain extent because unemployed cash-help recipient ability affects participation in activation. Municipalities can improve activation efficiency levels in the future by emulating the efficient municipalities...

  17. Measurements for municipalities 2007

    NARCIS (Netherlands)

    B. Kuhry; J.J.J. Jonker; with participation of M. Ras

    2007-01-01

    Original title: Maten voor gemeenten 2007. Measurements for municipalities 2007 presents a national picture of the performance delivered by local authorities and the costs of doing so. The analyses relate to the period 2000-2005. This is the fifth time this quantitative and integrated picture

  18. Measurements for municipalities 2006

    NARCIS (Netherlands)

    B. Kuhry; J.J.J. Jonker; with cooperation of Bureau Zenc

    2006-01-01

    Original title: Maten voor gemeenten 2006. Measurements for municipalities 2006 (Maten voor gemeenten 2006) presents a national picture of the performance delivered by local authorities and the costs of doing so. The analyses relate to the period 1999-2004. This is the fourth time

  19. Measurements for municipalities 2012

    NARCIS (Netherlands)

    Evert Pommer; Ingrid Ooms; Ab van der Torre; Saskia Jansen

    2012-01-01

    Original title: Maten voor gemeenten 2012 Local authorities in the Netherlands are playing an ever more important role in the delivery of services to citizens, as more and more tasks are transferred from central to local government. Dutch municipalities spent a combined total of 56 billion

  20. The slag original from the process of sewage sludge incineration selected properties characteristic

    Science.gov (United States)

    Głowacka, Anna; Rucińska, Teresa; Kiper, Justyna

    2017-11-01

    This work characterizes the physical and chemical properties of slag from combustion of municipal sewage sludge in "Pomorzany" waste treatment plant in Szczecin. The technology of sludge management is based on drying the sludge in low-temperature belt driers, to a content level of at least 90%, dry mass., and then burning in a grate boiler with mobile grate. The research of the slag resulting from combustion of municipal sewage sludge was conducted using reference methods, presenting images from a scanning electron microscope. The tested waste contained from 16.300 to 23.150% P2O5 completely soluble in strong acids, pH 8.03, mineral substance 98.73% dry mass. The content of heavy metals did not exceed the permissible amount specified in the Regulation of the Minister of Agriculture and Rural Development of 18 June 2008 on the implementation of certain provisions of the Act on fertilizers and fertilization (Journal of Laws of 2008 No. 119, item. 765). The screening trials showed that 48.4% are fractions of 630 µm-1.25 mm. The results show that the waste code 19 01 12 may be used as: alternative source of phosphorus for direct application to soil treatment, for production of organic - mineral fertilizers and as construction aggregate for production of concrete mortars.

  1. Full-scale performance of selected starch-based biodegradable polymers in sludge dewatering and recommendation for applications.

    Science.gov (United States)

    Zhou, Kuangxin; Stüber, Johan; Schubert, Rabea-Luisa; Kabbe, Christian; Barjenbruch, Matthias

    2018-01-01

    Agricultural reuse of dewatered sludge is a valid route for sludge valorization for small and mid-size wastewater treatment plants (WWTPs) due to the direct utilization of nutrients. A more stringent of German fertilizer ordinance requires the degradation of 20% of the synthetic additives like polymeric substance within two years, which came into force on 1 January 2017. This study assessed the use of starch-based polymers for full-scale dewatering of municipal sewage sludge. The laboratory-scale and pilot-scale trials paved the way for full-scale trials at three WWTPs in Germany. The general feasibility of applying starch-based 'green' polymers in full-scale centrifugation was demonstrated. Depending on the sludge type and the process used, the substitution potential was up to 70%. Substitution of 20-30% of the polyacrylamide (PAM)-based polymer was shown to achieve similar total solids (TS) of the dewatered sludge. Optimization of operational parameters as well as machinery set up in WWTPs is recommended in order to improve the shear stability force of sludge flocs and to achieve higher substitution potential. This study suggests that starch-based biodegradable polymers have great potential as alternatives to synthetic polymers in sludge dewatering.

  2. Steam generator sludge removal apparatus

    International Nuclear Information System (INIS)

    Schafer, B.W.; Werner, C.E.; Klahn, F.C.

    1992-01-01

    The present invention relates to equipment for cleaning steam generators and in particular to a high pressure fluid lance for cleaning sludge off the steam generator tubes away from an open tube lane. 6 figs

  3. Processing method for radioactive sludge

    International Nuclear Information System (INIS)

    Shoji, Yuichi; Kaneko, Masaaki.

    1993-01-01

    The concentration of radioactive sludges contained in a storage tank is controlled, thereafter, a filter is charged into a processing vessel to continuously conduct dewatering. Then, the radioactive sludges and an oxidizer are mixed by stirring using a stirring impeller and by vibrations using a vibrator. At the same time, thermic rays are irradiated by using infrared ray lamps to heat and decompose them. Since thermic rays reach the center of the radioactive sludges by the infrared ray lamps, ion exchange resins are sufficiently decomposed and carbonized into inorganic material. Then, a filling hardener such as mortar cement having a good flowability is charged to solidify the wastes. With such procedures, radioactive sludges can be stored under a stable condition for a long period of time by decomposing organic materials into inorganic materials and solidifying them. Further, an operator's radiation exposure dose can remarkably be reduced by applying a predetermined and a stabilization treatment in an identical processing vessel. (N.H.)

  4. Enhanced sludge washing evaluation plan

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, R.D.

    1994-09-01

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

  5. Enhanced sludge washing evaluation plan

    International Nuclear Information System (INIS)

    Jensen, R.D.

    1994-09-01

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices

  6. 77 FR 14574 - Self-Regulatory Organizations; Municipal Securities Rulemaking Board; Notice of Filing of...

    Science.gov (United States)

    2012-03-12

    ... Consisting of Establishment of Historical Data Subscription from Submissions to the MSRB Electronic Municipal... historical documents and data obtained from submissions to the MSRB Electronic Municipal Market Access System... information available to the public, at no charge on a Web portal or by paid subscription feed. The text of...

  7. 78 FR 44607 - Self-Regulatory Organizations; Municipal Securities Rulemaking Board; Notice of Filing of a...

    Science.gov (United States)

    2013-07-24

    ... (collectively ``regulated entities''). It is governed by a 21- member board composed of eleven independent... directors in overseeing the municipal securities market, it is imperative that the board identify candidates... non- dealer municipal advisors. The public representatives must be independent of any regulated entity...

  8. Cost and value of pathogen reduction for land application of sludges

    International Nuclear Information System (INIS)

    Sivinski, H.D.; Morris, M.E.

    1978-03-01

    This paper discusses the general pressures that are forcing sewage sludge managers to reconsider land application of sludges where it is not already used; presents the cost of using gamma-radiation from the isotope cesium-137 for sludge disinfection; and documents the economic and social pressures that could compel a city such as Washington, D.C. to disinfect its compost before sale. Washington was chosen as an example because it is a city for which suitable compost marketing data are readily available. With these data it is reasonably straightforward to document the costs and benefits of radiation processing. The economic and social pressures that affect Washington are probably similar to those in many other areas where the radiation disinfection of dried sludge could provide the same disposal options

  9. Air Emission Reduction Benefits of Biogas Electricity Generation at Municipal Wastewater Treatment Plants.

    Science.gov (United States)

    Gingerich, Daniel B; Mauter, Meagan S

    2018-02-06

    Conventional processes for municipal wastewater treatment facilities are energy and materially intensive. This work quantifies the air emission implications of energy consumption, chemical use, and direct pollutant release at municipal wastewater treatment facilities across the U.S. and assesses the potential to avoid these damages by generating electricity and heat from the combustion of biogas produced during anaerobic sludge digestion. We find that embedded and on-site air emissions from municipal wastewater treatment imposed human health, environmental, and climate (HEC) damages on the order of $1.63 billion USD in 2012, with 85% of these damages attributed to the estimated consumption of 19 500 GWh of electricity by treatment processes annually, or 0.53% of the US electricity demand. An additional 11.8 million tons of biogenic CO 2 are directly emitted by wastewater treatment and sludge digestion processes currently installed at plants. Retrofitting existing wastewater treatment facilities with anaerobic sludge digestion for biogas production and biogas-fueled heat and electricity generation has the potential to reduce HEC damages by up to 24.9% relative to baseline emissions. Retrofitting only large plants (>5 MGD), where biogas generation is more likely to be economically viable, would generate HEC benefits of $254 annually. These findings reinforce the importance of accounting for use-phase embedded air emissions and spatially resolved marginal damage estimates when designing sustainable infrastructure systems.

  10. Municipal Solid Waste Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Municipal solid waste (MSW) is a source of biomass material that can be utilized for bioenergy production with minimal additional inputs. MSW resources include mixed commercial and residential garbage such as yard trimmings, paper and paperboard, plastics, rubber, leather, textiles, and food wastes. Waste resources such as landfill gas, mill residues, and waste grease are already being utilized for cost-effective renewable energy generation. MSW for bioenergy also represents an opportunity to divert greater volumes of residential and commercial waste from landfills.

  11. Mercado municipal Can Vidalet

    OpenAIRE

    Romero Francisco, Jorge

    2006-01-01

    La intención del nuevo mercado municipal de Can Vidalet es crear un escenario en sombra, envuelto por una piel permeable; una "cesta" dentro de la cual se produce una actividad comercial. La topografía del lugar permite establecer un esquema comercial en sección, situando el mercado tradicional en cota superior y el nuevo uso comercial en planta baja, a nivel de plaza pública.

  12. Near-bottom pelagic bacteria at a deep-water sewage sludge disposal site

    Energy Technology Data Exchange (ETDEWEB)

    Takizawa, M.; Straube, W.L.; Hill, R.T.; Colwell, R.R.

    1994-01-01

    The epibenthic bacterial community at deep-ocean sewage sludge disposal site DWD-106, located approximately 106 miles (ca. 196 km) off the coast of New Jersey, was assessed for changes associated with the introduction of large amounts of sewage sludge. Mixed cultures and bacterial isolates obtained from water overlying sediment core samples collected at the deep-water (2,500 m) municipal sewage disposal site were tested for the ability to grow under in situ conditions of temperature and pressure. The responses of cultures collected at a DWD-106 station heavily impacted by sewage sludge were compared with those of samples collected from a station at the same depth which was not contaminated by sewage sludge. Significant differences were observed in the ability of mixed bacterial cultures and isolates from the two sites to grow under deep-sea pressure and temperature conditions. The levels of sludge contamination were established by enumerating Clostridium perfringens, a sewage indicator bacterium, in sediment samples from the two sites. (Copyright (c) 1993, American Society for Microbiology.)

  13. Analysis of briquetting process of sewage sludge with coal to combustion process

    Directory of Open Access Journals (Sweden)

    Kosturkiewicz Bogdan

    2016-01-01

    Full Text Available Energy recovery from sewage sludge can be achieved by several thermal technologies, but before those processes sewage sludge requires special pretreatment. The paper presents the investigation of the sewage sludge with coal briquettes as a fuel for combustion process. Research is conducted at Department of Manufacturing Systems and Department of Thermal Engineering and Environmental Protection, AGH University of Science and Technology to develop a technology of briquette preparation. The obtained results showed possibility of briquetting of municipal sewage sludge with coal in roll presses, equipped with asymmetric thickening gravity feed system. The following properties were determined for the obtained briquettes: density, drop strength and compressive strength. Based on physical and chemical analysis of prepared briquettes it was confirmed that briquettes have good fuel properties to combustion process. Thermal behaviour of studied sewage sludge and prepared mixture was investigated by thermogravimetric analysis (TG. For the thermo gravimetric analysis (TG the samples were heated in an alumina crucible from an ambient temperature up to 1000 °C at a constant rates: 10 °C/min, 40 °C/min and 100 °C/min in a 40 ml/min flow of air.

  14. APPLICATION OF RESPIROMETRIC TESTS FOR ASSESSMENT OF METHANOGENIC BACTERIA ACTIVITY IN WASTEWATER SLUDGE PROCESSING

    Directory of Open Access Journals (Sweden)

    Małgorzata Cimochowicz-Rybicka

    2013-07-01

    Full Text Available Production of a methane-rich gas (‘biogas’ is contemporary popular sludges processing technology which allows to generate thermal and/or electric energy. Formal requirements issued by the European Union to promote so called renewable energy resources made these process more attractive leading to its application in WWTPs which were designed based on different sludge handling processes. Authors (as active design engineers noted that dimensioning sludge digestion chamber is usually based on SRT assessment without any emphasis on sludge characteristics. Bio-mass characteristics and the estimation of its activity with respect to methane production are of great importance, from both scientific and practical points of view, as anaerobic digestion appears to be one of crucial processes in municipal wastewater handling and disposal. The authors propose respirometric tests to estimate a biomass potential to produce ‘a biogas’ and several years’ laboratory and full scale experience proved its usefulness and reliability both as a measurement and a design tool applicable in sludge handling. Dimensioning method proposed by authors, allows to construct and optimize operation of digestion chambers based on a methanogenic activity.

  15. A comparison of aerobic granular sludge with conventional and compact biological treatment technologies.

    Science.gov (United States)

    Bengtsson, Simon; de Blois, Mark; Wilén, Britt-Marie; Gustavsson, David

    2018-03-20

    The aerobic granular sludge (AGS) technology is growing towards becoming a mature option for new municipal wastewater treatment plants and capacity extensions. A process based on AGS was compared to conventional activated sludge processes (with and without enhanced biological phosphorus removal), an integrated fixed-film activated sludge (IFAS) process and a membrane bioreactor (MBR) by estimating the land area demand (footprint), electricity demand and chemicals' consumption. The process alternatives compared included pre-settling, sludge digestion and necessary post-treatment to achieve effluent concentrations of 8 mg/L nitrogen and 0.2 mg/L phosphorus at 7°C. The alternative based on AGS was estimated to have a 40-50% smaller footprint and 23% less electricity requirement than conventional activated sludge. In relation to the other compact treatment options IFAS and MBR, the AGS process had an estimated electricity usage that was 35-70% lower. This suggests a favourable potential for processes based on AGS although more available experience of AGS operation and performance at full scale is desired.

  16. Renewable municipal waste barometer

    International Nuclear Information System (INIS)

    2014-01-01

    In the European Union the production of primary energy from the incineration of municipal waste increased by only 0.7% in 2013 and reached 8.7 million tep (tonnes of oil equivalent). Germany ranks first with the production of 2729 ktep followed by France with 1246 ktep. A positive point is that the sale of heat to heat networks has strongly increased in some countries which means that primary energy is better used. 2 tables give the production of electricity and heat from the incineration of municipal waste in the E.U. member states in 2012 and 2013. Germany ranks first in the 2 tables. The total production of electricity and heat from the incineration of municipal waste in E.U. in 2013 reached 18741 GWh and 2361 tep respectively. A list reviews the most significant companies working in Europe in the sector of waste incineration, 8 companies are listed, 2 are German: EEW, Remondis, 3 are French: SITA (Suez Environment, Veolia and TIRU (EDF), Urbaser is spanish, Gruppo Hera is Italian and AEB-Amsterdan is dutch. (A.C.)

  17. Heating value characteristics of sewage sludge: a comparative study of different sludge types

    International Nuclear Information System (INIS)

    Kim, Young-JU.; Kang, Hae-Ok.; Qureshi, T.I.

    2005-01-01

    Heating value characteristics of three different types of sludge, i.e. domestic sewage sludge, industrial sludge, and industrial + domestic sewage sludge were investigated. Industrial + domestic sewage sludge (thickened) showed the highest heating value (5040 kcal/kg) than other sludge types. This may be due to increased amount of organic matter presents in thickened sludge than de-watered sludge. A gradual increase in organic matter of the sludge was observed with the increase of the moisture contents. Heating value of the sludge having 60% moisture contents was found in the range between 924-1656 kcal/kg and this amount was higher than the minimum heating value (800 kcal/kg) required sustaining auto thermal combustion in sludge incineration process. Energy consumption requirement for pre drying sludge operations revealed that industrial sludge (de-watered) required the minimum cost (13 $/ton of sludge) to make it a sludge of fuel grade (60% W), while mixed sludge cost the highest amount for its pre-drying operations. (author)

  18. Pentachlorophenol (PCP) sludge recycling unit

    International Nuclear Information System (INIS)

    1994-08-01

    The Guelph Utility Pole Company treats utility poles by immersion in pentachlorophenol (PCP) or by pressure treatment with chromated copper arsenate (CCA). The PCP treatment process involves a number of steps, each producing a certain amount of sludge and other wastes. In a plant upgrading program to improve processing and treatment of poles and to reduce and recycle waste, a PCP recovery unit was developed, first as an experimental pilot-scale unit and then as a full-scale unit. The PCP recovery unit is modular in design and can be modified to suit different requirements. In a recycling operation, the sludge is pumped through a preheat system (preheated by waste heat) and suspended solids are removed by a strainer. The sludge is then heated in a tank and at a predetermined temperature it begins to separate into its component parts: oil, steam, and solids. The steam condenses to water containing low amounts of light oil, and this water is pumped through an oil/water separator. The recovered oil is reused in the wood treatment process and the water is used in the CCA plant. The oil remaining in the tank is reused in PCP treatment and the solid waste, which includes small stones and wood particles, is removed and stored. By the third quarter of operation, the recovery unit was operating as designed, processing ca 10,000 gal of sludge. This sludge yielded 6,500 gal of water, 3,500 gal of oil, and ca 30 gal of solids. Introduction of the PCP sludge recycling system has eliminated long-term storage of PCP sludge and minimized costs of hazardous waste disposal. 4 figs

  19. Sludge reduction by ozone: Insights and modeling of the dose-response effects.

    Science.gov (United States)

    Fall, C; Silva-Hernández, B C; Hooijmans, C M; Lopez-Vazquez, C M; Esparza-Soto, M; Lucero-Chávez, M; van Loosdrecht, M C M

    2018-01-15

    Applying ozone to the return flow in an activated sludge (AS) process is a way for reducing the residual solids production. To be able to extend the activated sludge models to the ozone-AS process, adequate prediction of the tri-atoms effects on the particulate COD fractions is needed. In this study, the biomass inactivation, COD mineralization, and solids dissolution were quantified in batch tests and dose-response models were developed as a function of the reacted ozone doses (ROD). Three kinds of model-sludge were used. S1 was a lab-cultivated synthetic sludge with two components (heterotrophs X H and X P ). S2 was a digestate of S1 almost made by the endogenous residues, X P . S3 was from a municipal activated sludge plant. The specific ozone uptake rate (SO 3 UR, mgO 3 /gCOD.h) was determined as a tool for characterizing the reactivity of the sludges. SO 3 UR increased with the X H fraction and decreased with more X P . Biomass inactivation was exponential (e -β.ROD ) as a function of the ROD doses. The percentage of solids reduction was predictable through a linear model (C Miner  + Y sol ROD), with a fixed part due to mineralization (C Miner ) and a variable part from the solubilization process. The parameters of the models, i.e. the inactivation and the dissolution yields (β, 0.008-0.029 (mgO 3 /mgCOD ini ) -1 vs Y sol , 0.5-2.8 mg COD sol /mgO 3 ) varied in magnitude, depending on the intensity of the scavenging reactions and potentially the compactness of the flocs for each sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The hydraulic transportation of thickened sludges

    African Journals Online (AJOL)

    driniev

    non-Newtonian sludges (Xu et al., 1993; Spinosa and Lotita, 2001; .... [11]. Analysis and typical applications. Laminar/turbulent transition. For most sewage sludges the ... on Transport and Sedimentation of Solid Particles - Ghent, September.

  1. Microbiological aspects of granular methanogenic sludge

    NARCIS (Netherlands)

    Dolfing, J.

    1987-01-01

    The settling characteristics of anaerobic sludge are enhanced by the formation of microbial conglomerates. Various types of conglomerates having different structures, were distinguished in the present study, viz. granules, pellets and flocs (chapter 1). Granular methanogenic sludge, often

  2. Biological sludge solubilisation for reduction of excess sludge production in wastewater treatment process.

    Science.gov (United States)

    Yamaguchi, T; Yao, Y; Kihara, Y

    2006-01-01

    A novel sludge disintegration system (JFE-SD system) was developed for the reduction of excess sludge production in wastewater treatment plants. Chemical and biological treatments were applied to disintegrate excess sludge. At the first step, to enhance biological disintegration, the sludge was pretreated with alkali. At the second step, the sludge was disintegrated by biological treatment. Many kinds of sludge degrading microorganisms integrated the sludge. The efficiency of the new sludge disintegration system was confirmed in a full-scale experiment. The JFE-SD system reduced excess sludge production by approximately 50% during the experimental period. The quality of effluent was kept at quite a good level. Economic analysis revealed that this system could significantly decrease the excess sludge treatment cost.

  3. The role and control of sludge age in biological nutrient removal activated sludge systems.

    Science.gov (United States)

    Ekama, G A

    2010-01-01

    The sludge age is the most fundamental and important parameter in the design, operation and control of biological nutrient removal (BNR) activated sludge (AS) systems. Generally, the better the effluent and waste sludge quality required from the system, the longer the sludge age, the larger the biological reactor and the more wastewater characteristics need to be known. Controlling the reactor concentration does not control sludge age, only the mass of sludge in the system. When nitrification is a requirement, sludge age control becomes a requirement and the secondary settling tanks can no longer serve the dual purpose of clarifier and waste activated sludge thickeners. The easiest and most practical way to control sludge age is with hydraulic control by wasting a defined proportion of the reactor volume daily. In AS plants with reactor concentration control, nitrification fails first. With hydraulic control of sludge age, nitrification will not fail, rather the plant fails by shedding solids over the secondary settling tank effluent weirs.

  4. Assessment and analysis of industrial liquid waste and sludge disposal at unlined landfill sites in arid climate

    International Nuclear Information System (INIS)

    Al Yaqout, Anwar F.

    2003-01-01

    Municipal solid waste disposal sites in arid countries such as Kuwait receive various types of waste materials like sewage sludge, chemical waste and other debris. Large amounts of leachate are expected to be generated due to the improper disposal of industrial wastewater, sewage sludge and chemical wastes with municipal solid waste at landfill sites even though the rainwater is scarce. Almost 95% of all solid waste generated in Kuwait during the last 10 years was dumped in five unlined landfills. The sites accepting liquid waste consist of old sand quarries that do not follow any specific engineering guidelines. With the current practice, contamination of the ground water table is possible due to the close location of the water table beneath the bottom of the waste disposal sites. This study determined the percentage of industrial liquid waste and sludge of the total waste dumped at the landfill sites, analyzed the chemical characteristics of liquid waste stream and contaminated water at disposal sites, and finally evaluated the possible risk posed by the continuous dumping of such wastes at the unlined landfills. Statistical analysis has been performed on the disposal and characterization of industrial wastewater and sludge at five active landfill sites. The chemical analysis shows that all the industrial wastes and sludge have high concentrations of COD, suspended solids, and heavy metals. Results show that from 1993 to 2000, 5.14±1.13 million t of total wastes were disposed per year in all active landfill sites in Kuwait. The share of industrial liquid and sludge waste was 1.85±0.19 million t representing 37.22±6.85% of total waste disposed in all landfill sites. Such wastes contribute to landfill leachate which pollutes groundwater and may enter the food chain causing adverse health effects. Lined evaporation ponds are suggested as an economical and safe solution for industrial wastewater and sludge disposal in the arid climate of Kuwait

  5. Analysis on carbon dioxide emission reduction during the anaerobic synergetic digestion technology of sludge and kitchen waste: Taking kitchen waste synergetic digestion project in Zhenjiang as an example.

    Science.gov (United States)

    Guo, Qia; Dai, Xiaohu

    2017-11-01

    With the popularization of municipal sewage treatment facilities, the improvement of sewage treatment efficiency and the deepening degree of sewage treatment, the sludge production of sewage plant has been sharply increased. Carbon emission during the process of municipal sewage treatment and disposal has become one of the important sources of greenhouse gases that cause greenhouse effect. How to reduce carbon dioxide emissions during sewage treatment and disposal process is of great significance for reducing air pollution. Kitchen waste and excess sludge, as two important organic wastes, once uses anaerobic synergetic digestion technology in the treatment process can on the one hand, avoid instability of sludge individual anaerobic digestion, improve sludge degradation rate and marsh gas production rate, and on the other hand, help increase the reduction of carbon dioxide emissions to a great extent. The paper uses material balance method, analyzes and calculates the carbon dioxide emissions from kitchen waste and sludge disposed by the anaerobic synergetic digestion technology, compares the anaerobic synergetic digestion technology with traditional sludge sanitary landfill technology and works out the carbon dioxide emission reductions after synergetic digestion. It takes the kitchen waste and sludge synergetic digestion engineering project of Zhenjiang city in Jiangsu province as an example, makes material balance analysis using concrete data and works out the carbon dioxide daily emission reductions. The paper analyzes the actual situation of emission reduction by comparing the data, and found that the synergetic digestion of kitchen waste and sludge can effectively reduce the carbon dioxide emission, and the reduction is obvious especially compared with that of sludge sanitary landfill, which has a certain effect on whether to promote the use of the technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Integral study of sewage sludges

    International Nuclear Information System (INIS)

    1994-01-01

    Sewage sludges are the by-product generated during the treatment process of waste water, and they are conformed by a solid phase which origin is the accumulation of pollutant materials which has been added to water during natural and anthropogenic activities. Its handling is one of the most serious problems faced by water treatment plants which involve the production, gathering, transportation, re utilization and final disposal of sewage sludges. The main purpose of this project is to perform a technical evaluation of the process of sewage sludge irradiation for its possible application as a choice for treatment and final disposal. Irradiation with gammas from Cobalt-60 shows effectiveness in disinfestation of sewage sludges, since they reduce six times the microbial population with a 7 KGy dose. In like manners with doses of 10 KGy is possible to bring down in 70 % the concentration of organic compounds, as well as to eliminate the presence of 6 to 22 organic compounds on samples of sewage sludges. The whole content of this work is presented in six sections: Introduction, Antecedents, Methodology, Conclusions, Suggestions and Bibliography. (Author)

  7. Excess sludge reduction in activated sludge processes by integrating ultrasound treatment

    International Nuclear Information System (INIS)

    Perez-Elvira, S.; Fdz-Polanco, M.; Plaza, F. I.; Garralon, G.; Fdz-Polanco, F.

    2009-01-01

    Biological sludge produced in the activated sludge process can be minimised modifying the water line, the sludge line or the final disposal strategy. Selecting the water line the general idea is to reduce the sludge producing the yield coefficient by means of the called lysis cryptic growth process. The main techniques referenced in literature are onization, chlorination and chemical and heat treatment. Ultrasounds are widely used to increase anaerobic biodegradability but are not reported as system to control excess sludge production. (Author)

  8. Application of the NDHA model to describe N2O dynamics in activated sludge mixed culture biomass

    DEFF Research Database (Denmark)

    Domingo-Felez, Carlos; Smets, Barth F.

    A pseudo-mechanistic model describing three biological nitric oxide (NO) and nitrous oxide (N2O) production pathways was calibrated for an activated sludge mixed culture biomass treating municipal wastewater with laboratory-scale experiments. The model (NDHA) comprehensively describes N2O produci...

  9. Pharmaceuticals and personal care products in untreated and treated sewage sludge: Occurrence and environmental risk in the case of application on soil - A critical review.

    Science.gov (United States)

    Verlicchi, P; Zambello, E

    2015-12-15

    This review is based on 59 papers published between 2002 and 2015, referring to about 450 treatment trains providing data regarding sludge concentrations for 169 compounds, specifically 152 pharmaceuticals and 17 personal care products, grouped into 28 different classes. The rationale of the study is to provide data to evaluate the environmental risk posed by the spreading of treated sludge in agriculture. Following discussion of the legislative scenario governing the final disposal of treated sludge in European countries and the USA, the study provides a snapshot of the occurrence of selected compounds in primary, secondary, mixed, digested, conditioned, composted and dried sludge originating in municipal wastewater treatment plants fed mainly with urban wastewater as well as in sludge-amended soil. Not only are measured values reported, but also predicted concentrations based on Kd values are reported. It emerges that in secondary sludge, the highest concentrations were found for fragrances, antiseptics and antibiotics and an attenuation in their concentrations occurs during treatment, in particular anaerobic digestion and composting. An in-depth literature survey of the (measured and predicted) Kd values for the different compounds and treated sludge are reported and an analysis of the influence of pH, redox conditions, sludge type was carried out. The data regarding measured and predicted concentrations of selected compounds in sludge-amended soil is then analyzed. Finally an environmental risk assessment posed by their occurrence in soil in the case of land application of sludge is examined, and the results obtained by different authors are compared. The most critical compounds found in the sludge-amended soil are estradiol, ciprofloxacin, ofloxacin, tetracycline, caffeine, triclosan and triclocarban. The study concludes with a focus on the main issues that should be further investigated in order to refine the environmental risk assessment. Copyright © 2015

  10. Supplementary information on K-Basin sludges

    International Nuclear Information System (INIS)

    MAKENAS, B.J.

    1999-01-01

    Three previous documents in this series have been published covering the analysis of: K East Basin Floor and Pit Sludge, K East Basin Canister Sludge, and K West Basin Canister Sludge. Since their publication, additional data have been acquired and analyses performed. It is the purpose of this volume to summarize the additional insights gained in the interim time period

  11. 40 CFR 61.54 - Sludge sampling.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Sludge sampling. 61.54 Section 61.54... sampling. (a) As an alternative means for demonstrating compliance with § 61.52(b), an owner or operator... days prior to a sludge sampling test, so that he may at his option observe the test. (c) Sludge shall...

  12. Heavy metals precipitation in sewage sludge

    NARCIS (Netherlands)

    Marchioretto, M.M.; Rulkens, W.H.; Bruning, H.

    2005-01-01

    There is a great need for heavy metal removal from strongly metal-polluted sewage sludges. One of the advantages of heavy metal removal from this type of sludge is the possibility of the sludge disposal to landfill with reduced risk of metals being leached to the surface and groundwater. Another

  13. Impact of fertilizing with raw or anaerobically digested sewage sludge on the abundance of antibiotic-resistant coliforms, antibiotic resistance genes, and pathogenic bacteria in soil and on vegetables at harvest.

    Science.gov (United States)

    Rahube, Teddie O; Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Duenk, Peter; Lapen, David R; Topp, Edward

    2014-11-01

    The consumption of crops fertilized with human waste represents a potential route of exposure to antibiotic-resistant fecal bacteria. The present study evaluated the abundance of bacteria and antibiotic resistance genes by using both culture-dependent and molecular methods. Various vegetables (lettuce, carrots, radish, and tomatoes) were sown into field plots fertilized inorganically or with class B biosolids or untreated municipal sewage sludge and harvested when of marketable quality. Analysis of viable pathogenic bacteria or antibiotic-resistant coliform bacteria by plate counts did not reveal significant treatment effects of fertilization with class B biosolids or untreated sewage sludge on the vegetables. Numerous targeted genes associated with antibiotic resistance and mobile genetic elements were detected by PCR in soil and on vegetables at harvest from plots that received no organic amendment. However, in the season of application, vegetables harvested from plots treated with either material carried gene targets not detected in the absence of amendment. Several gene targets evaluated by using quantitative PCR (qPCR) were considerably more abundant on vegetables harvested from sewage sludge-treated plots than on vegetables from control plots in the season of application, whereas vegetables harvested the following year revealed no treatment effect. Overall, the results of the present study suggest that producing vegetable crops in ground fertilized with human waste without appropriate delay or pretreatment will result in an additional burden of antibiotic resistance genes on harvested crops. Managing human exposure to antibiotic resistance genes carried in human waste must be undertaken through judicious agricultural practice. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Municipal recycling support program. Guide to applicants

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The Municipal Recycling Support Program stems from the Ontario Ministry of the Environment's policies and programs begun in 1980 aimed at encouraging the development of source separation projects in Ontario. To qualify for financial assistance, municipalities must play a central role in the implementation and ongoing development of recycling; applications will be supported only if there is adequate and reasonable commitment from markets for recovered materials; recycling systems must operate within the framework of a complete waste management system in which cost effectiveness is an important factor; multi-material projects are encouraged as much as possible; and the Ministry will share the costs of projects with the municipalities. The Ministry provides grants for up to 5 years per project to cover the net operating cost of a project up to a specified maximum percentage of eligible gross operating expenses. This manual provides guidelines for applying for such funding, including definitions of eligibility for operating and capital costs, the use of household bins, and guidelines for promotion and advertising, education, demonstration, and feasibility studies.

  15. Sewage sludge - arisings, composition, disposal capacities; Klaerschlamm - Mengen, Zusammensetzung, Entsorgungskapazitaeten

    Energy Technology Data Exchange (ETDEWEB)

    Faulstich, M.; Rabus, J. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl fuer Wasserguete- und Abfallwirtschaft; Urban, A.I.; Friedel, M. [Kassel Univ. (Gesamthochschule) (Germany). Fachgebiet Abfalltechnik

    1998-09-01

    One of the main disposal paths for sewage sludge in the past was landfilling. This option was severely restricted by the issue of the Technical Code on Household Waste in 1993. In its agricultural applications sewage sludge serves as a fertiliser and a soil improvement agent. Estimates on potential thermal treatment capacities have shown that there are enough public power plants to accommodate and provide thermal treatment for the total of sewage sludge arisings in Germany. As can be seen from the estimates presented in this paper, it would not even be necessary to restrict oneself to public power plant capacities. The paper points out possibilities of using plant capacities already existing in industrial firing plants and certain production sectors. It uses a comparison to show that sewage sludge would have to be dried in order to permit its thermal treatment in these private facilities. Aside from this, there are a number of new techniques entering the market which from the technical viewpoint also appear to be well suited for thermal sewage sludge treatment. [Deutsch] Ein wesentlicher Entsorgungsweg von Klaerschlamm war in der Vergangenheit die Verbringung auf eine Deponie. Diese Moeglichkeit ist durch die TA Siedlungsabfall von 1993 stark eingeschraenkt. Bei der landwirtschaftlichen Verwertung wird durch den Klaerschlamm eine Duengewirkung sowie eine Bodenverbesserung erreicht. Eine Abschaetzung der potentiellen thermischen Behandlungskapazitaeten zeigt, dass die gesamte bundesdeutsche Klaerschlammenge in oeffentlichen Kraftwerken unterzubringen und thermisch zu behandeln waere. Wie die hier dargestellten Abschaetzungen gezeigt haben, ist man durchaus nicht allein auf die Nutzung oeffentlicher Kraftwerkskapazitaeten angewiesen. Es wurden Moeglichkeiten zur Nutzung vorhandener Anlagenkapazitaeten in industriellen Feuerungsanlagen und in Produktionsbereichen aufgezeigt. Wie aus einem Vergleich erkennbar wird, ist allerdings eine Trocknung der Klaerschlaemme

  16. Innovation Management in Swedish Municipalities

    OpenAIRE

    Wihlman, Thomas; Hoppe, Magnus; Wihlman, Ulla; Sandmark, Hélène

    2016-01-01

    Research on public sector innovation is still limited, and increased knowledge of innovation processes is needed. This article is a based on a study of the implementation of innovation policies in Swedish municipalities, and gives a first-hand, empirical view of some of the complexities of innovation in the public sector. The study took place in four municipalities in central Sweden. The municipalities varied in size and organisational forms. Interviews and policy documents were used for data...

  17. Greening Public Buildings: ESCO-Contracting in Danish Municipalities

    Directory of Open Access Journals (Sweden)

    Jesper Rohr Hansen

    2013-05-01

    Full Text Available This paper presents current research on Danish municipalities’ use of Energy Service Companies (ESCO as a way to improve the standard of public buildings and to increase energy efficiency. In recent years more and more municipalities have used ESCO-contracts to retrofit existing public buildings, and to make them more energy efficient. At the moment 30 municipalities (of the 98 municipalities in Denmark are involved in, or preparing, ESCO contracts. Nevertheless, ESCO-contracting still faces many challenges on the Danish market, as there is a widespread skepticism towards the concept amongst many stakeholders. The purpose of this paper is to discuss the various experience gained so far by municipalities use of ESCO-contracting, the different approached to ESCO-contracting being used in practice, as well as the different viewpoints drivers and barriers behind the development. The strong growth in ESCO-contracts reflects that the ESCO-concept fits well with a number of present problems that municipalities are facing, as well as a flexible adaptation to the local context in different municipalities.

  18. Chemical modeling of waste sludges

    International Nuclear Information System (INIS)

    Weber, C.F.; Beahm, E.C.

    1996-10-01

    The processing of waste from underground storage tanks at the Oak Ridge National Laboratory (ORNL) and other facilities will require an understanding of the chemical interactions of the waste with process chemicals. Two aspects of sludge treatment should be well delineated and predictable: (1) the distribution of chemical species between aqueous solutions and solids, and (2) potential problems due to chemical interactions that could result in process difficulties or safety concerns. It is likely that the treatment of waste tank sludge will begin with washing, followed by basic or acidic leaching. The dissolved materials will be in a solution that has a high ionic strength where activity coefficients are far from unity. Activity coefficients are needed in order to calculate solubilities. Several techniques are available for calculating these values, and each technique has its advantages and disadvantages. The techniques adopted and described here is the Pitzer method. Like any of the methods, prudent use of this approach requires that it be applied within concentration ranges where the experimental data were fit, and its use in large systems should be preceded by evaluating subsystems. While much attention must be given to the development of activity coefficients, other factors such as coprecipitation of species and Ostwald ripening must also be considered when one aims to interpret results of sludge tests or to predict results of treatment strategies. An understanding of sludge treatment processes begins with the sludge tests themselves and proceeds to a general interpretation with the aid of modeling. One could stop with only data from the sludge tests, in which case the table of data would become an implicit model. However, this would be a perilous approach in situations where processing difficulties could be costly or result in concerns for the environment or health and safety

  19. Ecological and Economic Aspects of the Application of Sewage Sludge in Energetic Plant Plantations - A Swot Analysis

    Science.gov (United States)

    Wójcik, Marta; Stachowicz, Feliks; Masłoń, Adam

    2017-12-01

    Sewage sludge management in Poland is a relatively new field of waste management called "in statu nascendi", the standards of which have not been recognized yet. It also requires the implementation of new solutions in the field of sewage sludge. So far, the most popular method of sewage sludge utilization has been landfill disposal. In line with the restriction placed on landfill waste with a calorific value above 6 MJ/kg introduced on 1 January 2016, agricultural use and thermal methods are particularly applied. Municipal sewage sludge may be successfully used in the cultivation of energetic plant plantations. The aforementioned waste could be treated as an alternative to traditional mineral fertilizers, which in turn might successfully provide valuable nutrients for plants. This paper illustrates the SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) associated with the use of sewage sludge from Świlcza-Kamyszyn WTTP (Podkarpackie Province, Poland) for agricultural purposes. This analysis could be useful in evaluating the utility of sewage sludge in perennial plant plantations in order to determine the appropriate waste management strategies.

  20. Intersectoriality in Danish municipalities

    DEFF Research Database (Denmark)

    Heering Holt, Ditte; Frohlich, Katherine L; Tjørnhøj-Thomsen, Tine

    2017-01-01

    healthier practices into various settings, e.g. creating healthy school environments for increased physical activity and healthy eating. While other more overarching interventions on the health impacts of broader welfare policies (e.g. education policy) tend to be neglected. The interventions hereby neglect...... the intersectoral policy process legitimates certain practices in the setting of Danish municipal health promotion and the potential impact this can have for long-term, sustainable healthy public policy. Based on ethnographic fieldwork, we show how the intention of intersectoriality produces a strong concern...

  1. Critical operational parameters for zero sludge production in biological wastewater treatment processes combined with sludge disintegration.

    Science.gov (United States)

    Yoon, Seong-Hoon; Lee, Sangho

    2005-09-01

    Mathematical models were developed to elucidate the relationships among process control parameters and the effect of these parameters on the performance of anoxic/oxic biological wastewater processes combined with sludge disintegrators (A/O-SD). The model equations were also applied for analyses of activated sludge processes hybrid with sludge disintegrators (AS-SD). Solubilization ratio of sludge in the sludge disintegrator, alpha, hardly affected sludge reduction efficiencies if the biomass was completely destructed to smaller particulates. On the other hand, conversion efficiency of non-biodegradable particulates to biodegradable particulates, beta, significantly affected sludge reduction efficiencies because beta was directly related to the accumulation of non-biodegradable particulates in bioreactors. When 30% of sludge in the oxic tank was disintegrated everyday and beta was 0.5, sludge reduction was expected to be 78% and 69% for the A/O-SD and AS-SD processes, respectively. Under this condition, the sludge disintegration number (SDN), which is the amount of sludge disintegrated divided by the reduced sludge, was calculated to be around 4. Due to the sludge disintegration, live biomass concentration decreased while other non-biodegradable particulates concentration increased. As a consequence, the real F/M ratio was expected to be much higher than the apparent F/M. The effluent COD was maintained almost constant for the range of sludge disintegration rate considered in this study. Nitrogen removal efficiencies of the A/O-SD process was hardly affected by the sludge disintegration until daily sludge disintegration reaches 40% of sludge in the oxic tank. Above this level of sludge disintegration, autotrophic biomass concentration decreases overly and TKN in the effluent increases abruptly in both the A/O-SD and AS-SD processes. Overall, the trends of sludge reduction and effluent quality according to operation parameters matched well with experimental results

  2. Contamination of a municipal sewage system with polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) with precipitation. Phase 1 (1990-1992)

    International Nuclear Information System (INIS)

    McLachlan, M.S.; Reissinger, M.; Horstmann, M.; Kaune, A.; Buresch, H.; Hutzinger, O.

    1992-09-01

    The purpose of the project was to estimate and assess the contamination of a municipal sewerage with PCDD/F through precipitation. Potential sources such as the rainwash of rooves and roads were examined directly. The last stages in the sewage transport are waters or water purification plants. Primary sludge, the most important accumulating compartment for PCDD/F, was also examined. (BBR) [de

  3. Anaerobic digestion of industrial activated aerobic sludge

    International Nuclear Information System (INIS)

    Goodloe, J.G.; Roberts, R.S.

    1990-04-01

    The Tennessee Eastman Company manufactures a variety of organic chemicals, plastics and fibers at their Kingsport Tennessee Facility. The wastewater generated during the manufacture of these compounds is currently treated using an activated sludge process. The objective of the project is to evaluate the economic potential of an anaerobic digestion process to convert industrial sludge at the Tennessee Eastman Company into biogas. The evaluation will require collection and analysis of experimental data on the anaerobic digestion of industrial sludge obtained from Kingsport. Although the experiments will be conducted using Tennessee Eastman sludge, these results should be also generally applicable to similar industrial sludge

  4. Improvement of municipal wastewater pretreatment by direct membrane filtration.

    Science.gov (United States)

    Nascimento, Thiago A; Mejía, Fanny R; Fdz-Polanco, Fernando; Peña Miranda, Mar

    2017-10-01

    The high content of particulate matter in municipal wastewater hinders the conventional anaerobic treatments at psychrophilic temperatures. The hydrolysis of the particulate chemical oxygen demand (pCOD) could be the limiting step under these conditions. Therefore, new pretreatments or improved conventional pretreatments are needed in order to separate pCOD. In this work, direct membrane filtration of municipal wastewater, using an ultrafiltration membrane, was investigated. This intensive pretreatment, which aims to separate soluble chemical oxygen demand (sCOD) and to concentrate pCOD, together with anaerobic treatments of both streams at psychrophilic and mesophilic conditions respectively, could be an alternative to the conventional activated sludge process. The obtained results show a removal yield of 24.9% of the total solids (TS) and 45% of total chemical oxygen demand (tCOD), obtaining a permeate free of suspended solids. This physical removal implies the accumulation of solids inside the membrane tank, reaching the values of 45.4 and 4.4 g/L of TS in the sedimentation and filtration sections, respectively. The membrane operated with filtration, backwashing cycles and continuous gas sparging, with a permeate flux predominantly around 10 L/(m 2  h). The results show the viability of the technology to concentrate pCOD and so to improve energy recovery from municipal wastewater.

  5. Sludge cleaning in the steam generators: sludge Lancing e IBL

    International Nuclear Information System (INIS)

    Montoro, E.; Gonzalez, S.; Calderon, N.

    2013-01-01

    IBERDROLA Engineering and Construction has echoed the need for plants to remove oxide deposits (sludge) located on the secondary side, on the bottom plate and into the tube bundle steam steam generators. Therefore, and with its partner SAVAC SRA has developed a specific system consisting of applying a capillary water at very high pressure applied directly to the location of these oxides. (Author)

  6. Improved waste-activated sludge dewatering using sludge/oil ...

    African Journals Online (AJOL)

    2014-10-07

    Oct 7, 2014 ... 2Dept. of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seongdong-Gu, Seoul 133-791, ... conventional heating methods in chemical reactions is becom- ... the dewaterability of sludge and reduces the organic matter ..... It is unlikely that this technique will be applied in.

  7. GER values of recovered phosphorus. Chain analysis of struvite production from municipal wastewater and recovery of phosphorus from sludge incineration ash; GER-waarden van teruggewonnen fosfor. Ketenanalyse van struvietproductie uit communaal afvalwater en terugwinning van fosfor uit assen van slibverbranding

    Energy Technology Data Exchange (ETDEWEB)

    Croezen, H.; Bijleveld, M. [CE Delft, Delft (Netherlands); Mulder, M. [Mrabella Mulder Waste Water Management, Utrecht (Netherlands)

    2012-09-15

    Phosphorus recovery from wastewater is a topical issue and a process being applied increasingly in the Netherlands. As part of NL Agency's energy efficiency programme CE Delft has calculated the energy benefits of two alternative recovery options compared with conventional production routes. The Gross Energy Requirement (GER) was calculated for the following routes: struvite recovery from rejection water versus conventional fertilizer production and phosphorus recovery from sludge incineration ash at Thermphos versus phosphorus production from phosphate ore at Thermphos. Compared with the conventional routes, the two recovery routes yield energy gains. The project was carried out in cooperation with Mirabella Mulder Wastewater Management, with support from Thermphos [Dutch] Fosforterugwinning uit afvalwater is een onderwerp dat in de belangstelling staat en meer en meer in Nederland wordt toegepast. In het kader van het energie-efficiëntieprogramma van Agentschap NL heeft CE Delft berekend wat de energetische winst is van twee terugwinroutes ten opzichte van de huidige gangbare productieroutes. De Gross Energy Requirement is berekend voor de volgende routes: struvietwinning uit rejectiewater versus reguliere kunstmestproductie en winning van fosfor uit zuiveringsslibas bij Thermphos versus productie van fosfor uit fosfaaterts bij Thermphos. Vergeleken met de reguliere routes leveren beide terugwinroutes energiewinst op. Het project werd uitgevoerd in samenwerking met Mirabella Mulder Wastewater Management en met inbreng van Thermphos.

  8. Micropollutant degradation via extracted native enzymes from activated sludge.

    Science.gov (United States)

    Krah, Daniel; Ghattas, Ann-Kathrin; Wick, Arne; Bröder, Kathrin; Ternes, Thomas A

    2016-05-15

    A procedure was developed to assess the biodegradation of micropollutants in cell-free lysates produced from activated sludge of a municipal wastewater treatment plant (WWTP). This proof-of-principle provides the basis for further investigations of micropollutant biodegradation via native enzymes in a solution of reduced complexity, facilitating downstream protein analysis. Differently produced lysates, containing a variety of native enzymes, showed significant enzymatic activities of acid phosphatase, β-galactosidase and β-glucuronidase in conventional colorimetric enzyme assays, whereas heat-deactivated controls did not. To determine the enzymatic activity towards micropollutants, 20 compounds were spiked to the cell-free lysates under aerobic conditions and were monitored via LC-ESI-MS/MS. The micropollutants were selected to span a wide range of different biodegradabilities in conventional activated sludge treatment via distinct primary degradation reactions. Of the 20 spiked micropollutants, 18 could be degraded by intact sludge under assay conditions, while six showed reproducible degradation in the lysates compared to the heat-deactivated negative controls: acetaminophen, N-acetyl-sulfamethoxazole (acetyl-SMX), atenolol, bezafibrate, erythromycin and 10,11-dihydro-10-hydroxycarbamazepine (10-OH-CBZ). The primary biotransformation of the first four compounds can be attributed to amide hydrolysis. However, the observed biotransformations in the lysates were differently influenced by experimental parameters such as sludge pre-treatment and the addition of ammonium sulfate or peptidase inhibitors, suggesting that different hydrolase enzymes were involved in the primary degradation, among them possibly peptidases. Furthermore, the transformation of 10-OH-CBZ to 9-CA-ADIN was caused by a biologically-mediated oxidation, which indicates that in addition to hydrolases further enzyme classes (probably oxidoreductases) are present in the native lysates. Although the

  9. Filterability of membrane bioreactor (MBR) sludge: impacts of polyelectrolytes and mixing with conventional activated sludge.

    Science.gov (United States)

    Yigit, Nevzat O; Civelekoglu, Gokhan; Cinar, Ozer; Kitis, Mehmet

    2010-01-01

    The main objective of this work was to investigate the filterability of MBR sludge and its mixture with conventional activated sludge (CAS). In addition, the impacts of type and dose of various polyelectrolytes, filter type and sludge properties on the filterability of both MBR and Mixed sludges were determined. Specific cake resistance (SCR) measured by the Buchner funnel filtration test apparatus and the solids content of the resulting sludge cake were used to assess the dewaterability of tested sludges. The type of filter paper used in Buchner tests affected the results of filterability for MBR, CAS and Mixed sludges. SCR values and optimum polyelectrolyte doses increased with increasing MLSS concentrations in the MBR, which suggested that increase in MLSS concentrations accompanied by increases in EPS and SMP concentrations and a shift toward smaller particles caused poorer dewaterability of the MBR sludge. The significant differences observed among the filterability of CAS and MBR sludges suggested that MLSS alone is not a good predictor of sludge dewaterability. Combining CAS and MBR sludges at different proportions generally improved their dewaterability. Combining MBR sludges having typically high MLSS and EPS concentrations with CAS having much lower MLSS concentrations may be an option for full-scale treatment plants experiencing sludge dewaterability problems. Better filterability and higher cake dry solids were achieved with cationic polyelectrolytes compared to anionic and non-ionic ones for all sludge types tested.

  10. Electrodialytic removal of cadmium from wastewater sludge

    DEFF Research Database (Denmark)

    Jakobsen, M. R.; Fritt-Rasmussen, Janne; Nielsen, S.

    2004-01-01

    This paper presents for the first time laboratory results demonstrating electrodialytic removal of Cd from wastewater sludge, which is a method originally developed for soil remediation. During the remediation a stirred suspension of wastewater sludge was exposed to an electric dc field. The liquid....../solid (ml/g fresh sludge) ratio was between 1.4 and 2. Three experiments were performed where the sludge was suspended in distilled water, citric acid or HNO"3. The experimental conditions were otherwise identical. The Cd removal in the three experiments was 69, 70 and 67%, respectively, thus the removal...... was approximately the same. Chemical extraction experiments with acidic solutions showed that 5-10 times more Cd could be extracted from decomposed sludge than from fresh sludge. It is likely that the mobilization of Cd during decomposition of the sludge contributes to the efficient removal of Cd...

  11. Tracing pharmaceuticals in a municipal plant for integrated wastewater and organic solid waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    Jelic, Aleksandra [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Fatone, Francesco; Di Fabio, Silvia [Department of Biotechnology, University of Verona, Strada Le Grazie 15, I-37134, Verona (Italy); Interuniversity Consortium ' Chemistry for the Environment' (INCA), Via delle Industrie, I-30135, Marghera-Venice (Italy); Petrovic, Mira, E-mail: mpetrovic@icra.cat [Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluis Companys 23, 80010 Barcelona (Spain); Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, 101-E-17003 Girona (Spain); Cecchi, Franco [Department of Biotechnology, University of Verona, Strada Le Grazie 15, I-37134, Verona (Italy); Interuniversity Consortium ' Chemistry for the Environment' (INCA), Via delle Industrie, I-30135, Marghera-Venice (Italy); Barcelo, Damia [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, 101-E-17003 Girona (Spain)

    2012-09-01

    The occurrence and removal of 42 pharmaceuticals, belonging to different therapeutic groups (analgesics and anti-inflammatory drugs, anti-ulcer agent, psychiatric drugs, antiepileptic drug, antibiotics, ss-blockers, diuretics, lipid regulator and cholesterol lowering statin drugs and anti-histamines), were studied in the wastewater and sewage sludge trains of a full scale integrated treatment plant. The plant employs a biological nutrient removal (BNR) process for the treatment of municipal wastewater, and a single-stage mesophilic anaerobic co-digestion for the treatment of wasted activated sludge mixed with the organic fraction of municipal solid waste (OFMSW), followed by a short-cut nitrification-denitrification of the anaerobic supernatant in a sequential batch reactor. Influent and effluent wastewater, as well as thickened, digested and treated sludge were sampled and analyzed for the selected pharmaceuticals in order to study their presence and fate during the treatment. Twenty three compounds were detected in influent and effluent wastewater and eleven in sludge. Infiltration of groundwater in the sewer system led to a dilution of raw sewage, resulting in lower concentrations in wastewater (up to 0.7 {mu}g/L in influent) and sludge (70 ng/g d.w.). Due to the dilution, overall risk quotient for the mixture of pharmaceuticals detected in effluent wastewater was less than one, indicating no direct risk for the aquatic environment. A wide range of removal efficiencies during the treatment was observed, i.e. < 20% to 90%. The influent concentrations of the target pharmaceuticals, as polar compounds, were undoubtedly mostly affected by BNR process in the wastewater train, and less by anaerobic-co-digestion. Mass balance calculations showed that less than 2% of the total mass load of the studied pharmaceuticals was removed by sorption. Experimentally estimated distribution coefficients (< 500 L/kg) also indicated that the selected pharmaceuticals preferably remain

  12. Tracing pharmaceuticals in a municipal plant for integrated wastewater and organic solid waste treatment

    International Nuclear Information System (INIS)

    Jelic, Aleksandra; Fatone, Francesco; Di Fabio, Silvia; Petrovic, Mira; Cecchi, Franco; Barcelo, Damia

    2012-01-01

    The occurrence and removal of 42 pharmaceuticals, belonging to different therapeutic groups (analgesics and anti-inflammatory drugs, anti-ulcer agent, psychiatric drugs, antiepileptic drug, antibiotics, ß-blockers, diuretics, lipid regulator and cholesterol lowering statin drugs and anti-histamines), were studied in the wastewater and sewage sludge trains of a full scale integrated treatment plant. The plant employs a biological nutrient removal (BNR) process for the treatment of municipal wastewater, and a single-stage mesophilic anaerobic co-digestion for the treatment of wasted activated sludge mixed with the organic fraction of municipal solid waste (OFMSW), followed by a short-cut nitrification–denitrification of the anaerobic supernatant in a sequential batch reactor. Influent and effluent wastewater, as well as thickened, digested and treated sludge were sampled and analyzed for the selected pharmaceuticals in order to study their presence and fate during the treatment. Twenty three compounds were detected in influent and effluent wastewater and eleven in sludge. Infiltration of groundwater in the sewer system led to a dilution of raw sewage, resulting in lower concentrations in wastewater (up to 0.7 μg/L in influent) and sludge (70 ng/g d.w.). Due to the dilution, overall risk quotient for the mixture of pharmaceuticals detected in effluent wastewater was less than one, indicating no direct risk for the aquatic environment. A wide range of removal efficiencies during the treatment was observed, i.e. < 20% to 90%. The influent concentrations of the target pharmaceuticals, as polar compounds, were undoubtedly mostly affected by BNR process in the wastewater train, and less by anaerobic-co-digestion. Mass balance calculations showed that less than 2% of the total mass load of the studied pharmaceuticals was removed by sorption. Experimentally estimated distribution coefficients (< 500 L/kg) also indicated that the selected pharmaceuticals preferably remain

  13. Sewage sludge disposal-requirements, expense and acceptance; Klaerschlammentsorgung zwischen Anspruch, Aufwand und Akzeptanz

    Energy Technology Data Exchange (ETDEWEB)

    Gruenebaum, T. [Ruhrverband, Essen (Germany)

    1997-02-01

    Production of sewage sludges is unavoidable at wastewater treatment. Sewage sludges shall be used in agriculture. Although the content of hazardous substances in sewage sludges has obviously been minimized, the use of those sludges is limited because of the low acceptance in agriculture and food industry. Therefore it is necessary to build up methods of disposal which make possible and ensure a medium- or even longtime disposal. Incineration seems to be the solution since the requirements for landfill of sewage sludges have been renewed. The currently valid transitional regulation lead to remarkable reactions of the disposal market. The plans for sewage sludge disposal have to agree with the principles of environmental protection, safety, economic efficiency, good realization and operational handling. (orig.) [Deutsch] Bei der Abwasserreinigung faellt Klaerschlamm an. Dieser ist moeglichst in der Landwirtschaft zu verwerten. Obwohl die Schadstoffgehalte der Klaerschlaemme in den letzten 15 Jahren sehr deutlich gesunken sind, ist der Einsatz durch Akzeptanzprobleme in der Landwirtschaft und bei der Nahrungsmittelindustrie limitiert. Es gilt deshalb, Entsorgungspfade aufzubauen, die eine mittel- und langfristige Sicherung der Entsorgung ermoeglichen. Nach den neueren Anforderungen an eine Deponierung ist demnach immer eine Verbrennung vorzusehen. Die z.Z. noch geltende Uebergangsregelung hat zu massiven Reaktionen des Entsorgungsmarktes gefuehrt. Die Planungen zur Klaerschlammentsorgung muessen sich an den Grundsaetzen der Umsetzbarkeit und betrieblichen Handhabbarkeit ausrichten. (orig.)

  14. Soil and pasture P concentration in a Fraxinus excelsior L. silvopastoral system fertilised with different types of sewage sludge

    Science.gov (United States)

    Ferreiro-Domínguez, Nuria; Nair, Vimala; Rigueiro-Rodríguez, Antonio; Rosa Mosquera-Losada, María

    2015-04-01

    In Europe, sewage sludge should be stabilised before using as fertiliser in agriculture. Depending on the stabilisation process that is used, sewage sludge has different characteristics, nutrient contents and soil nutrient incorporation rates. Sewage sludge is usually applied on a plant-available N or total metal concentration basic, and therefore, P concentrations can be well above crop needs. Leaching of excess P can threaten surface and ground waters with eutrophication. In this context, recent studies have demonstrated that the implementation of agroforestry systems could reduce the P leaching risk compared with conventional agricultural systems due to the different localisation of tree and crop roots which enhance nutrient uptake. The aim of this study was to evaluate during three consecutive years the effect of municipal sewage sludge stabilised by anaerobic digestion, composting, and pelletisation on concentration of P in soil and pasture compared to control treatments (mineral and no fertilisation) in a silvopastoral system established under Fraxinus excelsior L. in Galicia (Spain). The results showed that at the beginning of the study, the fertilisation with mineral increased more the total and available P in soil than the fertilisation with sewage sludge probably because the sludge nutrient release rate is slower than those from mineral fertilisers. The increment of soil available P caused by the mineral fertiliser implied an improvement of the P concentration in the pasture. However, in the last year of the experiment it was observed a positive effect of the fertilisation with pelletised sludge on the concentration of P in pasture compared with the composted sludge and the mineral fertiliser probably due to the annual application of this type of sludge. Therefore, the establishment of silvopastoral systems and their fertilisation with pelletized sludge should be recommended because the pelletized sludge increases the concentration of P in the pasture and

  15. Solidification process for sludge residue

    International Nuclear Information System (INIS)

    Pearce, K.L.

    1998-01-01

    This report investigates the solidification process used at 100-N Basin to solidify the N Basin sediment and assesses the N Basin process for application to the K Basin sludge residue material. This report also includes a discussion of a solidification process for stabilizing filters. The solidified matrix must be compatible with the Environmental Remediation Disposal Facility acceptance criteria

  16. Sludge stabilization operability test report

    International Nuclear Information System (INIS)

    Lewis, W.S.

    1994-01-01

    Document provides the results of the Operability Test Procedure performed to test the operability of the HC-21C thermal stabilization process for sludge. The OTP assured all equipment functioned properly and established the baseline temperature profile for glovebox HC-21C

  17. Thermal analysis of kieselguhr sludge

    Directory of Open Access Journals (Sweden)

    S. T. Antipov

    2013-01-01

    Full Text Available It’s currently necessary to clarify the mechanisms of thermodynamic and mass transfer processes in capillary porous media. In this paper we obtain the thermogravimetric curves of evaporation drying kieselguhr sludge. It is also an analysis of the curves, allowing to choose the optimum conditions of drying.

  18. Fluidization of Dried Wastewater Sludge.

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Pohořelý, Michael; Trnka, Otakar

    2007-01-01

    Roč. 178, 3 (2007) , s. 166-172 ISSN 0032-5910 R&D Projects: GA AV ČR(CZ) IAA4072201 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidization characteristics * multiphase reactors * dried stabilized wastewater sludge Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.130, year: 2007

  19. Local democracy in large municipalities

    DEFF Research Database (Denmark)

    Thuesen, Annette Aagaard

    2017-01-01

    Municipal amalgamations in Denmark in 2007 led to concern for local rural democracy, as the number of politicians from rural areas dropped after the reform. To preserve rural democracy, local councils at the village level were established in some municipalities, and they have begun to prepare local...

  20. Adaptive Municipal e-forms

    NARCIS (Netherlands)

    Kuiper, P.M.; van Dijk, Elisabeth M.A.G.; Boerma, A.K.; Weibelzahl, S.; Cristea, A.

    2006-01-01

    Adaptation of electronic forms seems to be a step forward to reduce the burden for people who fill in forms. Municipalities more and more offer eforms online that can be used to request a municipal product or service. To create adaptive e-forms that satisfy the need of end-users, involvement of

  1. Study on Municipal Energy Companies

    International Nuclear Information System (INIS)

    2009-07-01

    This is a summarizing overview of the local, renewable energy initiatives that are grouped under the heading of 'municipal energy company'. A municipal energy company (or sustainable energy company) is a local energy company that initiates, coordinates and/or manages sustainable energy projects with the primary objective of realizing the climate objectives. [nl

  2. Fermentation and chemical treatment of pulp and paper mill sludge

    Science.gov (United States)

    Lee, Yoon Y; Wang, Wei; Kang, Li

    2014-12-02

    A method of chemically treating partially de-ashed pulp and/or paper mill sludge to obtain products of value comprising taking a sample of primary sludge from a Kraft paper mill process, partially de-ashing the primary sludge by physical means, and further treating the primary sludge to obtain the products of value, including further treating the resulting sludge and using the resulting sludge as a substrate to produce cellulase in an efficient manner using the resulting sludge as the only carbon source and mixtures of inorganic salts as the primary nitrogen source, and including further treating the resulting sludge and using the resulting sludge to produce ethanol.

  3. Environmental assessment of the Sibiu County, Romania: proposal for sewage sludge and OFMSW management

    Directory of Open Access Journals (Sweden)

    Trombin Gloria

    2017-01-01

    Full Text Available The aim of the work is to assess current solid waste management (SWM and wastewater treatment (WWT in the county of Sibiu, Romania. Sibiu is a region where industrialization and tourism are spreading constantly, while pollution monitoring and the introduction of circular economy (CE principles are still lacking. The environmental issues are mostly due to the absence of reliable sanitation systems, in particular for what concerns sewage sludge treatment. Moreover, Organic fraction from selective collection of municipal solid waste is still missing, since it is disposed of directly to landfill, increasing environmental pollution and contributing considerably to global warming. As a result, SWM and WWT should be improved at the same time, as sludge requires specific handlings in order to be safety disposed. The objective of the study is to investigate the introduction of affordable technological facilities able to treat sludge and the organic fraction of municipal solid waste, recovering, at least, the energy required for the working phase of the treatment plants. Anaerobic digestion resulted viable, but the organic fraction full stream collection seems to be the only way to have a significant energy recovery. From the financial point of view, the feasibility of this co-treatment option could count on specific opportunities that Romania has in the frame of the European Union context.

  4. Radiation disinfection of sewage sludge and composting of the irradiated sludge

    International Nuclear Information System (INIS)

    Hashimoto, Shoji; Nishimura, Koichi; Watanabe, Hiromasa; Kawakami, Waichiro

    1985-01-01

    In the radiation disinfected sewage sludge, its stabilization is necessary with the composting. In this disinfected sludge, there is no need of keeping it at high temperature at the cost of fermentation velocity. The fermentation velocity can thus be set to obtain its maximum value. In sewage sludge utilization of farm land, to prevent the contamination with pathogenic bacteria and the secondary pollution, the radiation disinfection of dehydrated sludge and the composting of the disinfected sludge have been studied. The disinfection effect when an electron accelerator is used for the radiation source is described. Then, the composting of the disinfected sludge is described in chemical kinetics of the microorganisms. (Mori, K.)

  5. Effects of Sludge-amendment on Mineralization of Pyrene and Microorganisms in Sludge and Soil

    DEFF Research Database (Denmark)

    Klinge, C; Gejlsbjerg, B; Ekelund, Flemming

    2001-01-01

    . Sludge-amendment enhanced the mineralization of pyrene in the soil compared to soil without sludge, and the most extensive mineralization was observed when the sludge was kept in a lump. The number of protozoa, heterotrophic bacteria and pyrene-mineralizing bacteria was much higher in the sludge compared...... to the soil. The amendment of sludge did not affect the number of protozoa and bacteria in the surrounding soil, which indicated that organic contaminants in the sludge had a little effect on the number of protozoa and bacteria in the surrounding soil...

  6. Assessment of heavy metal pollution with applications of sewage sludge and city compost for maximizing crop yields

    International Nuclear Information System (INIS)

    D'Souza, T.J.; Ramachandran, V.; Raghu, K.

    1997-01-01

    Land application of municipal sewage sludge and city compost as organic manures make it imperative to assess heavy-metal pollution in soils and crops. Greenhouse experiments, conducted on maize in a vertisol and an ultisol amended with various doses of dry sewage sludge and city compost from Mumbai, indicated significant increases in dry matter-yields only in the vertisol. Significantly higher concentrations of Zn, Cu, Co, Pb, Ni and Cd were obtained in plants grown in the amended ultisol, but not in the amended vertisol. As Cd is the most toxic, experiments were conducted with four contrasting soils amended with varying doses of Cd-enriched sewage sludge and city compost. Results showed significant reductions in dry-matter yields of maize shoots at the higher rates of sludge or compost in the ultisol and an alfisol, but with no significant effects in the vertisol or an entisol. The levels of Cd and Zn were significantly elevated in plants in all four soil types. There were negative residual effects from the sludge and compost amendments: dry-matter yields of a succeeding maize crop were decreased in the ultisol and alfisol. Experiments with soils amended with sludge enriched with either Cd or Zn at 80 mg kg -1 indicated significant reductions in dry matter in all soils with Cd, but not with Zn. The results demonstrate that sewage sludges and city composts may be effectively used for maximizing crop yields, especially in vertisols and entisols. However, caution has to be exercised when using sludges containing even relatively low levels of Cd, or high levels of Zn, depending upon soil type. (author)

  7. Hexavalent chromium removal using aerobic activated sludge batch ...

    African Journals Online (AJOL)

    The following Cr(VI) removal systems were tested: activated sludge alone; activated sludge with an external electron donor (5 g/. of lactose); activated sludge with PAC addition (4 g/.); activated sludge with both PAC and lactose; and PAC alone. The results reported here showed that activated sludges are capable of ...

  8. Treatment of old landfill leachate with high ammonium content using aerobic granular sludge.

    Science.gov (United States)

    Ren, Yanan; Ferraz, Fernanda; Kang, Abbass Jafari; Yuan, Qiuyan

    2017-01-01

    Aerobic granular sludge has become an attractive alternative to the conventional activated sludge due to its high settling velocity, compact structure, and higher tolerance to toxic substances and adverse conditions. Aerobic granular sludge process has been studied intensively in the treatment of municipal and industrial wastewater. However, information on leachate treatment using aerobic granular sludge is very limited. This study investigated the treatment performance of old landfill leachate with different levels of ammonium using two aerobic sequencing batch reactors (SBR): an activated sludge SBR (ASBR) and a granular sludge SBR (GSBR). Aerobic granules were successfully developed using old leachate with low ammonium concentration (136 mg L -1  NH 4 + -N). The GSBR obtained a stable chemical oxygen demand (COD) removal of 70% after 15 days of operation; while the ASBR required a start-up of at least 30 days and obtained unstable COD removal varying from 38 to 70%. Ammonium concentration was gradually increased in both reactors. Increasing influent ammonium concentration to 225 mg L -1  N, the GSBR removed 73 ± 8% of COD; while COD removal of the ASBR was 59 ± 9%. The GSBR was also more efficient than the ASBR for nitrogen removal. The granular sludge could adapt to the increasing concentrations of ammonium, achieving 95 ± 7% removal efficiency at a maximum influent concentration of 465 mg L -1  N. Ammonium removal of 96 ± 5% was obtained by the ASBR when it was fed with a maximum of 217 mg L -1  NH 4 + -N. However, the ASBR was partially inhibited by free-ammonia and nitrite accumulation rate increased up to 85%. Free-nitrous acid and the low biodegradability of organic carbon were likely the main factors affecting phosphorus removal. The results from this research suggested that aerobic granular sludge have advantage over activated sludge in leachate treatment.

  9. Effect of communities of ammonia-oxidizing bacteria on degradation of 17-alpha-ethynylestradiol by nitrifying activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Limpiyakorn, T.; Sermwaraphan, P.; Kurisu, F.

    2009-07-01

    An endocrine disrupting compound, 17-alpha-ethynylestradiol (EE2), is a synthetic estrogen used as a key ingredient in oral contraceptives pill. this persistent organic pollutant, no biodegradable by most microorganisms, is discharged via municipal waste streams to natural receiving waters. Recently, it was found that ammonia-oxidizing bacteria (AOB) in nitrifying activated sludge (NAS) enriched with high ammonium loads can degrade EE2 via co-metabolism during ammonia oxidation. (Author)

  10. Biosorption of Cd, Cr, Mn, and Pb from aqueous solutions by Bacillus sp strains isolated from industrial waste activate sludge

    OpenAIRE

    García, Rocío; Campos, Juan; Cruz, Julio Alfonso; Calderón, Ma. Elena; Raynal, Ma. Elena; Buitrón, Germán

    2016-01-01

    Abstract The microorganisms are capable of accumulating heavy metal ions from water as biosorbent agents, offering a potential alternative for the detoxification and recovery of toxic/precious metals in industrial wastewater. In the present work, metal-resistant bacterial strains were isolated and identified from activated sludge of a waste treatment plant in the Municipality of Santa Rosa Jauregui, Querétaro. To obtain bacteria tolerant to metals, 37 bacterial strains and two isolates were s...

  11. The fate of radionuclides in sewage sludge applied to land

    International Nuclear Information System (INIS)

    Boston, H.L.; Van Miegroet, H.; Larsen, I.L.; Walzer, A.E.; Carlton, J.E.

    1990-01-01

    Municipal sewage sludge containing up to 12 pCi/g 137 Cs, 20 pCi/g 60 Co, and 300 ppm U was injected in a pasture (43 Mg/ha) and sprayed over a young pine plantation (34 Mg/ha). In the pasture, radionuclides were largely retained in the upper 15 cm of the soil, and only about 15% moved below 15 cm. Sludge rapidly infiltrated the soil on the pine plantation. One year after application, at least 85% of the 137 Cs, 60 Co, and U were found in the upper 7 cm of the pine plantation, with only about 15% moving into the 7- to 15-cm strata. On-site total added radiation dose was 2 to 6 mrem/year. Radionuclides were not detected above background in soil solutions at ∼50 cm depth or in shallow down-gradient groundwater wells. Surface runoff from application areas did not have elevated radionuclide concentrations. Concentrations of these radionuclides increased slightly in vegetation on treated sites, and uranium was notably higher in earthworms. 9 refs., 2 tabs

  12. Sludge derived fuel technique of sewage sludge by oil vacuum evaporation drying

    International Nuclear Information System (INIS)

    Kim, Seokhwan; Lim, Byungran; Lee, Sookoo

    2010-01-01

    Sewage sludge contains high content of organic materials and its water content is also very high about 80% even after filtration process. Landfill as a sludge treatment methods can cause odor problem and leachate production which can derive the secondary contamination of soil and groundwater. The ocean dumping will be prohibited according to the London Convention and domestic stringent environmental regulation. Based on domestic agenda on organic sewage sludge treatment, the ocean disposal will be prohibited from 2012, thus alternative methods are demanded. Sludge derived fuel (SDF) technology can alleviate the emission of greenhouse gas and recover energy from sludge. For proper treatment and SDF production from sludge, the vacuum evaporation and immersion frying technology was adopted in this research. This technology dries moisture in sludge after mixing with oil such as Bunker C oil, waste oil or waste food oil etc. Mixing sludge and oil secures liquidity of organic sludge to facilitate handling throughout the drying process. The boiling temperature could be maintained low through vacuum condition in whole evaporation process. This study was performed to find the optimum operating temperature and pressure, the mixing ratio of sludge and oil. Finally, we could obtained SDF which moisture content was less than 5%, its heating value was over 4,500 kcal/ kg sludge. This heating value could satisfy the Korean Fuel Standard for the Recycle Products. Assessed from the perspective of energy balance and economic evaluation, this sludge drying system could be widely used for the effective sludge treatment and the production of SDF. (author)

  13. 40 CFR Appendix A to Part 503 - Procedure To Determine the Annual Whole Sludge Application Rate for a Sewage Sludge

    Science.gov (United States)

    2010-07-01

    ... Whole Sludge Application Rate for a Sewage Sludge A Appendix A to Part 503 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SEWAGE SLUDGE STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE Pt... a Sewage Sludge Section 503.13(a)(4)(ii) requires that the product of the concentration for each...

  14. Municipalities and energy efficiency in countries in transition

    International Nuclear Information System (INIS)

    Rezessy, Silvia; Dimitrov, Konstantin; Urge-Vorsatz, Diana; Baruch, Seth

    2006-01-01

    It is widely recognized that many cost-efficient opportunities to employ end-use energy efficiency measures exist in countries in transition (CITs) and that municipal authorities have an essential role to play in capturing these opportunities. The aim of this paper is to review the factors that determine the degree of involvement of local authorities in the market for energy services and energy efficient (EE) equipment in three CITs: Bulgaria, Hungary and the Former Yugoslav Republic of Macedonia (hereafter: Macedonia). We achieve this aim by examining the current status of local governments as the most powerful determinant of municipal market involvement. Two broad groups of factors are discussed: statutory obligations and powers of local governments, especially energy-related tasks, and finance. We explain how specific features within these two areas may influence the motivation of local authorities to improve energy efficiency and their capacity to do so. We argue that greater decentralization is the first step in augmenting the role of local authorities in the market for energy services and EE equipment. Based on the analysis we give recommendations on how to encourage municipal authorities to use market mechanisms more extensively to deliver energy efficiency

  15. Beneficial uses of nuclear waste/sewage sludge irradiation project. Progress report, April 1981-September 1981

    International Nuclear Information System (INIS)

    1982-05-01

    The objective is the further development and transfer of sludge irradiation technology to the municipal sector. At the conclusion of this project, a number of sludge irradiation demonstration plants will have been constructed and placed in operation by municipalities across the country. The following program elements have been established to ensure successful accomplishment of the program objectives: technology transfer by means of municipal demonstration plants; research support and data base development through operation of the SIDSS (Sandia Irradiator for Dried Sewage Solids) pilot plant; engineering support for the demonstration plants by SNL and LANL to include required support for NEPA/licensing activities, risk assessment, safety, and basic design engineering support to A and E firms; life sciences and agricultural R and D support by NMSU for base program activities and for demonstration plants; quality assurance activities to support licensing and other requirements; and program management. During the period covered by this report, the objectives of the BU/SSIP project have been expanded to include determination of an appropriate role for DOE and SNL in food irradiation. Progress on the program elements for the period April 1, 1981 through September 30, 1981, is discussed in detail

  16. Speciation evolution of zinc and copper during pyrolysis and hydrothermal carbonization treatments of sewage sludges.

    Science.gov (United States)

    Huang, Rixiang; Zhang, Bei; Saad, Emily M; Ingall, Ellery D; Tang, Yuanzhi

    2018-04-01

    Thermal and hydrothermal treatments are promising techniques for sewage sludge management that can potentially facilitate safe waste disposal, energy recovery, and nutrient recovery/recycling. Content and speciation of heavy metals in the treatment products affect the potential environmental risks upon sludge disposal and/or application of the treatment products. Therefore, it is important to study the speciation transformation of heavy metals and the effects of treatment conditions. By combining synchrotron X-ray spectroscopy/microscopy analysis and sequential chemical extraction, this study systematically characterized the speciation of Zn and Cu in municipal sewage sludges and their chars derived from pyrolysis (a representative thermal treatment technique) and hydrothermal carbonization (HTC; a representative hydrothermal treatment technique). Spectroscopy analysis revealed enhanced sulfidation of Zn and Cu by anaerobic digestion and HTC treatments, as compared to desulfidation by pyrolysis. Overall, changes in the chemical speciation and matrix properties led to reduced mobility of Zn and Cu in the treatment products. These results provide insights into the reaction mechanisms during pyrolysis and HTC treatments of sludges and can help evaluate the environmental/health risks associated with the metals in the treatment products. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Guidance for writing permits for the use or disposal of sewage sludge. Draft report

    Energy Technology Data Exchange (ETDEWEB)

    1993-03-01

    Section 405(d) of the Clean Water Act (CWA) directs the U.S. Environmental Protection Agency (EPA) to develop regulations containing guidelines for the use and disposal of sewage sludge. On February 19th, 1993, EPA published final regulations at 40 Code of Federal Regulations (CFR) Part 503 as the culmination of a major effort to develop technical standards in response to Section 405(d). These regulations govern three sewage sludge use and disposal practices: land application, surface disposal, and incineration. A key element in EPA's implementation of the Part 503 regulations is educating Agency and State personnel about these new requirements. Although the regulations are generally directly enforceable against all persons involved in the use and disposal of sewage sludge, they will also be implemented through permits issued to treatment works treating domestic sewage as defined in 40 CFR 122.22. Thus, the primary focus of the manual is to assist permit writers in incorporating the Part 503 requirements into permits; it serves as an update to the Guidance for Writing Case-by-Case Permit Conditions for Municipal Sewage Sludge (PB91-145508/HDM).

  18. Innovative reuse of drinking water sludge in geo-environmental applications.

    Science.gov (United States)

    Caniani, D; Masi, S; Mancini, I M; Trulli, E

    2013-06-01

    In recent years, the replacement of natural raw materials with new alternative materials, which acquire an economic, energetic and environmental value, has gained increasing importance. The considerable consumption of water has favoured the increase in the number of drinking water treatment plants and, consequently, the production of drinking water sludge. This paper proposes a protocol of analyses capable of evaluating chemical characteristics of drinking water sludge from surface water treatment plants. Thereby we are able to assess their possible beneficial use for geo-environmental applications, such as the construction of barrier layers for landfill and for the formation of "bio-soils", when mixed with the stabilized organic fraction of municipal solid waste. This paper reports the results of a study aimed at evaluating the quality and environmental aspects of reconstructed soils ("bio-soil"), which are used in much greater quantities than the usual standard, for "massive" applications in environmental actions such as the final cover of landfills. The granulometric, chemical and physical analyses of the sludge and the leaching test on the stabilized organic fraction showed the suitability of the proposed materials for reuse. The study proved that the reuse of drinking water sludge for the construction of barrier layers and the formation of "bio-soils" reduces the consumption of natural materials, the demand for landfill volumes, and offers numerous technological advantages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. [Distribution and removal of anaerobic antibiotic resistant bacteria during mesophilic anaerobic digestion of sewage sludge].

    Science.gov (United States)

    Tong, Juan; Wang, Yuan-Yue; Wei Yuan, Song

    2014-10-01

    Sewage sludge is one of the major sources that releasing antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARG) into the environment since it contains large amount of ARB, but there is little information about the fate of the anaerobic ARB in the anaerobic digestion of sewage sludge. Therefore, the distribution, removal and seasonal changes of tetracycline and β-lactam antibiotics resistant bacteria in the mesophilic egg-shaped digesters of a municipal wastewater treatment plant were investigated for one year in this study. Results showed that there were higher amounts of ARB and higher resistance rate of β-lactam antibiotics than that of tetracycline antibiotics in the sewage sludge. All ARB could be significantly reduced during the mesophilic anaerobic digestion process by 1.48-1.64 log unit (P anaerobic digestion by 12.0% and 14.3%, respectively (P bacteria, there were more ARB in the sewage sludge in cold season than in warm season (P < 0.05).

  20. Speciation evolution of zinc and copper during pyrolysis and hydrothermal carbonization treatments of sewage sludges

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Rixiang; Zhang, Bei; Saad, Emily M.; Ingall, Ellery D.; Tang, Yuanzhi

    2018-04-01

    Thermal and hydrothermal treatments are promising techniques for sewage sludge management that can potentially facilitate safe waste disposal, energy recovery, and nutrient recovery/recycling. Content and speciation of heavy metals in the treatment products affect the potential environmental risks upon sludge disposal and/or application of the treatment products. Therefore, it is important to study the speciation transformation of heavy metals and the effects of treatment conditions. By combining synchrotron X-ray spectroscopy/microscopy analysis and sequential chemical extraction, this study systematically characterized the speciation of Zn and Cu in municipal sewage sludges and their chars derived from pyrolysis (a representative thermal treatment technique) and hydrothermal carbonization (HTC; a representative hydrothermal treatment technique). Spectroscopy analysis revealed enhanced sulfidation of Zn and Cu by anaerobic digestion and HTC treatments, as compared to desulfidation by pyrolysis. Overall, changes in the chemical speciation and matrix properties led to reduced mobility of Zn and Cu in the treatment products. These results provide insights into the reaction mechanisms during pyrolysis and HTC treatments of sludges and can help evaluate the environmental/health risks associated with the metals in the treatment products.