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Sample records for aerobic landfill bioreactor

  1. Aerobic landfill bioreactor

    SciTech Connect

    Hudgins, Mark P; Bessette, Bernard J; March, John; McComb, Scott T.

    2000-01-01

    The present invention includes a method of decomposing municipal solid waste (MSW) within a landfill by converting the landfill to aerobic degradation in the following manner: (1) injecting air via the landfill leachate collection system (2) injecting air via vertical air injection wells installed within the waste mass; (3) applying leachate to the waste mass using a pressurized drip irrigation system; (4) allowing landfill gases to vent; and (5) adjusting air injection and recirculated leachate to achieve a 40% to 60% moisture level and a temperature between 120.degree. F. and 140.degree. F. in steady state.

  2. Aerobic landfill bioreactor

    SciTech Connect

    Hudgins, Mark P; Bessette, Bernard J; March, John C; McComb, Scott T.

    2002-01-01

    The present invention includes a system of decomposing municipal solid waste (MSW) within a landfill by converting the landfill to aerobic degradation in the following manner: (1) injecting air via the landfill leachate collection system (2) injecting air via vertical air injection wells installed within the waste mass; (3) applying leachate to the waste mass using a pressurized drip irrigation system; (4) allowing landfill gases to vent; and (5) adjusting air injection and recirculated leachate to achieve a 40% to 60% moisture level and a temperature between 120.degree. F. and 140.degree. F. in steady state.

  3. Aerobic landfill bioreactor

    SciTech Connect

    Hudgins, M.P.; Bessette, B.J.; March, J.; McComb, S.T.

    2000-02-15

    The present invention includes a method of decomposing municipal solid waste (MSW) within a landfill by converting the landfill to aerobic degradation in the following manner: (1) injecting air via the landfill leachate collection system (2) injecting air via vertical air injection wells installed within the waste mass; (3) applying leachate to the waste mass using a pressurized drip irrigation system; (4) allowing landfill gases to vent; and (5) adjusting air injection and recirculated leachate to achieve a 40% to 60% moisture level and a temperature between 120 F and 140 F in steady state.

  4. COMMERCIAL-SCALE AEROBIC-ANAEROBIC BIOREACTOR LANDFILL OPERATIONS

    EPA Science Inventory

    A sequential aerobic-anaerobic treatment system has been applied at a commercial scale (3,000 ton per day) municipal solid waste landfill in Kentucky, USA since 2001. In this system, the uppermost layer of landfilled waste is aerated and liquid waste including leachate, surface w...

  5. Monitoring operational and leachate characteristics of an aerobic simulated landfill bioreactor.

    PubMed

    Giannis, A; Makripodis, G; Simantiraki, F; Somara, M; Gidarakos, E

    2008-01-01

    Long-term biodegradation of MSW in an aerobic landfill bioreactor was monitored as a function of time during 510 days of operation. Operational characteristics such as air importation, temperature and leachate recirculation were monitored. The oxygen utilization rates and biodegradation of organic matter rates showed that aerobic biodegradation was feasible and appropriate to proceed in aerobic landfill bioreactor. Leachate analyses showed that the aerobic bioreactor could remove above 90% of chemical oxygen demand (COD) and close to 100% of biochemical oxygen demand (BOD5) from leachate. Ammonium (NH4+), nitrate (NO3-) and sulphate (SO4(2-)) concentrations of leachate samples were regularly measured. Results suggest that nitrification and denitrification occurred simultaneously, and the increase in nitrate did not reach the levels predicted stoichiometrically, suggesting that other processes were occurring. Leachate recirculation reduced the concentrations of heavy metals because of the effect of the high pH of the leachate, causing heavy metals to be retained by processes such as sorption on MSW, carbonate precipitation, and hydroxide precipitation. Furthermore, the compost derived from the aerobic biodegradation of the organic matter of MSW may be considered as soil improvement in the agricultural plant production. Bio-essays indicated that the ecotoxicity of leachate from the aerobic bioreactor was not toxic at the end of the experiment. Finally, after 510 days of degradation, waste settlement reached 26% mainly due to the compost of the organic matter.

  6. Simulation of municipal solid waste degradation in aerobic and anaerobic bioreactor landfills.

    PubMed

    Patil, Bhagwan Shamrao; C, Agnes Anto; Singh, Devendra Narain

    2017-03-01

    Municipal solid waste generation is huge in growing cities of developing nations such as India, owing to the rapid industrial and population growth. In addition to various methods for treatment and disposal of municipal solid waste (landfills, composting, bio-methanation, incineration and pyrolysis), aerobic/anaerobic bioreactor landfills are gaining popularity for economical and effective disposal of municipal solid waste. However, efficiency of municipal solid waste bioreactor landfills primarily depends on the municipal solid waste decomposition rate, which can be accelerated through monitoring moisture content and temperature by using the frequency domain reflectometry probe and thermocouples, respectively. The present study demonstrates that these landfill physical properties of the heterogeneous municipal solid waste mass can be monitored using these instruments, which facilitates proper scheduling of the leachate recirculation for accelerating the decomposition rate of municipal solid waste.

  7. Yolo County's Accelerated Anaerobic and Aerobic Composting (Full-Scale Controlled Landfill Bioreactor) Project

    NASA Astrophysics Data System (ADS)

    Yazdani, R.; Kieffer, J.; Akau, H.; Augenstein, D.

    2002-12-01

    Sanitary landfilling is the dominant method of solid waste disposal in the United States, accounting for about 217 million tons of waste annually (U.S. EPA, 1997) and has more than doubled since 1960. In spite of increasing rates of reuse and recycling, population and economic growth will continue to render landfilling as an important and necessary component of solid waste management. Yolo County Department of Planning and Public Works, Division of Integrated Waste Management is demonstrating a new landfill technology called Bioreactor Landfill to better manage solid waste. In a Bioreactor Landfill, controlled quantities of liquid (leachate, groundwater, gray-water, etc.) are added and recirculated to increase the moisture content of the waste and improve waste decomposition. As demonstrated in a small-scale demonstration project at the Yolo County Central Landfill in 1995, this process significantly increases the biodegradation rate of waste and thus decreases the waste stabilization and composting time (5 to 10 years) relative to what would occur within a conventional landfill (30 to 50 years or more). When waste decomposes anaerobically (in absence of oxygen), it produces landfill gas (biogas). Biogas is primarily a mixture of methane, a potent greenhouse gas, carbon dioxide, and small amounts of Volatile Organic Compounds (VOC's) which can be recovered for electricity or other uses. Other benefits of a bioreactor landfill composting operation include increased landfill waste settlement which increases in landfill capacity and life, improved leachate chemistry, possible reduction of landfill post-closure management time, opportunity to explore decomposed waste for landfill mining, and abatement of greenhouse gases through highly efficient methane capture over a much shorter period of time than is typical of waste management through conventional landfilling. This project also investigates the aerobic decomposition of waste of 13,000 tons of waste (2.5 acre) for

  8. Degradation of municipal solid waste in simulated landfill bioreactors under aerobic conditions.

    PubMed

    Slezak, Radoslaw; Krzystek, Liliana; Ledakowicz, Stanislaw

    2015-09-01

    In this study the municipal solid waste degradation processes in simulated landfill bioreactors under aerobic and anaerobic conditions is investigated. The effect of waste aeration on the dynamics of the aerobic degradation processes in lysimeters as well as during anaerobic processes after completion of aeration is presented. The results are compared with the anaerobic degradation process to determine the stabilization stage of waste in both experimental modes. The experiments in aerobic lysimeters were carried out at small aeration rate (4.41⋅10(-3)lmin(-1)kg(-1)) and for two recirculation rates (24.9 and 1.58lm(-3)d(-1)). The change of leachate and formed gases composition showed that the application of even a small aeration rate favored the degradation of organic matter. The amount of CO2 and CH4 released from anaerobic lysimeter was about 5 times lower than that from the aerobic lysimeters. Better stabilization of the waste was obtained in the aerobic lysimeter with small recirculation, from which the amount of CO2 produced was larger by about 19% in comparison with that from the aerobic lysimeter with large leachate recirculation.

  9. Start-up of the SHARON and ANAMMOX process in landfill bioreactors using aerobic and anaerobic ammonium oxidising biomass.

    PubMed

    Shalini, S Sri; Joseph, Kurian

    2013-12-01

    The main aim of this study is to analyse the feasibility to use aerobic ammonium oxidising bacteria (AOB) and anammox/AnAOB biomass enriched from mined municipal solid waste for in situ SHARON and ANAMMOX processes in laboratory scale landfill bioreactors (LFBR) for ammonia nitrogen removal. For this purpose, three LFBRs were operated as Control (without biomass seed), SHARON (with AOB biomass seed) and ANAMMOX (with anammox biomass seed) for 315 days. Results showed nitrogen loading rate of 1.0 kg N/d was effectively removed in SHARON and ANAMMOX LFBR. In SHARON LFBR, partial nitritation efficiency reached up to 98.5% with AOB population of MPN of 5.1 × 10(6)/mL obtained. ANAMMOX LFBR gave evolution of 95% of nitrogen gas as the end product confirmed the ANAMMOX process. Nitrogen transformations, biomass development and hydrazine and hydroxylamine formation authenticated the enriched AOB and anammox biomass activity in landfill bioreactors.

  10. BIOREACTOR LANDFILL DESIGN

    EPA Science Inventory

    Modern landfill design entails many elements including foundations, liner systems, leachate collection systems, stormwater control systems, slope stability considerations, leachate management systems, gas extraction systems, and capping and closure. The use of bioreactor technolo...

  11. Landfill bioreactor design and operation

    SciTech Connect

    Reinhart, D.R.; Townsend, T.

    1998-12-31

    Landfill Bioreactor Design and Operation covers the history and background of landfill technology, research studies of actual bioreactor landfills, expected leachate and gas yields, specific design criteria, operation guidelines, and reuse of landfill sites to avoid having to establish new sites. For anyone looking for an alternative to large, wasteful landfill sites, this book provides a practical alternative to the problem.

  12. Pilot aerobic membrane bioreactor and nanofiltration for municipal landfill leachate treatment.

    PubMed

    Amaral, Míriam C S; Moravia, Wagner G; Lange, Liséte C; Zico, Mariana R; Magalhães, Natalie C; Ricci, Bárbara C; Reis, Beatriz G

    2016-07-02

    The purpose of this article is to evaluate the integration of the air stripping, membrane bioreactor (MBR) and nanofiltration (NF) processes for the treatment of landfill leachate (LFL). Pretreatment by air stripping, without adjustment of pH, removed 65% of N-NH3 present in LFL. After pretreatment, the effluent was treated in MBR obtaining 44% of COD removal, and part of the N-NH3 was converted to nitrite and nitrate, which was later removed in the post-treatment. Nanofiltration was shown to be an effective process to improve the removal of organic compounds, the high toxicity present in LFL and nitrite and nitrate generated in the MBR. The system (air stripping + MBR + nanofiltration) obtained great efficiency of removal in most parameters analyzed, with overall removal of COD, ammonia, color and toxicity approximately 88, 95, 100 and 100%, respectively. By this route, treated landfill leachate may be reused at the landfill as water for dust arrestment and also as earth work on construction sites.

  13. Heavy metal leaching from aerobic and anaerobic landfill bioreactors of co-disposed municipal solid waste incineration bottom ash and shredded low-organic residues.

    PubMed

    Inanc, Bulent; Inoue, Yuzo; Yamada, Masato; Ono, Yusaku; Nagamori, Masanao

    2007-03-22

    In this study, heavy metal leaching from aerobic and anaerobic landfill bioreactor test cells for co-disposed municipal solid waste incineration (MSWI) bottom ash and shredded low-organic residues has been investigated. Test cells were operated for 1 year. Heavy metals which were comparatively higher in leachate of aerobic cell were copper (Cu), lead (Pb), boron (B), zinc (Zn), manganese (Mn) and iron (Fe), and those apparently lower were aluminum (Al), arsenic (As), molybdenum (Mo), and vanadium (V). However, no significant release of heavy metals under aerobic conditions was observed compared to anaerobic and control cells. Furthermore, there was no meaningful correlation between oxidation-reduction potential (ORP) and heavy metal concentrations in the leachates although some researchers speculate that aeration may result in excessive heavy metal leaching. No meaningful correlation between dissolved organic carbon (DOC) and leaching of Cu and Pb was another interesting observation. The only heavy metal that exceeded the state discharge limits (10mg/l, to be enforced after April 2005) in the aerobic cell leachate samples was boron and there was no correlation between boron leaching and ORP. Higher B levels in aerobic cell should be due to comparatively lower pH values in this cell. However, it is anticipated that this slightly increased concentrations of B (maximum 25mg/l) will not create a risk for bioreactor operation; rather it should be beneficial for long-term stability of the landfill through faster washout. It was concluded that aerobization of landfills of heavy metal rich MSWI bottom ash and shredded residues is possible with no dramatic increase in heavy metals in the leachate.

  14. An assessment of bioreactor landfill costs and benefits.

    PubMed

    Berge, Nicole D; Reinhart, Debra R; Batarseh, Eyad S

    2009-05-01

    Because effective operation of bioreactor landfills involves careful operation and construction of infrastructure beyond that necessary in traditional landfills, upfront capital and operating costs are greater than those associated with traditional landfills. Prior to investing in bioreactor landfills, landfill owners must be convinced that larger short-term expenses (e.g., liquid and/or air injection infrastructure) will be balanced by future economic benefits (e.g., extension of landfill life, reduced leachate treatment costs, etc.). The purpose of this paper is to describe an economic model developed to evaluate the impact of various operational (anaerobic, aerobic, or hybrid) and construction (retrofit and as-built) bioreactor landfill strategies on project economics. Model results indicate retrofit bioreactor landfills are more expensive than traditional landfills, while both the as-built and aerobic bioreactor landfills are less costly. Simulation results indicate the parameters that influence bioreactor economics most significantly are airspace recovery, gas recovery and subsequent use to generate electricity, and savings resulting from reduced leachate treatment costs.

  15. PRACTICE REVIEW OF FIVE BIOREACTOR/RECIRCULATION LANDFILLS

    EPA Science Inventory

    Six bioreactor landfills were analyzed to provide a perspective of current practice and technical issues that differentiate bioreactor landfills from conventional landfills. Five of the bioreactor landfills were anaerobic and one was aerated. In one case, nearly identical cells e...

  16. BIOREACTOR LANDFILLS, THEORETICAL ADVANTAGES AND RESEARCH CHALLENGES

    EPA Science Inventory

    Bioreactor landfills are municipal solid waste landfills that utilize bulk liquids in an effort to accelerate solid waste degradation. There are few potential benefits for operating a MSW landfill as a bioreactor. These include leachate treatment and management, increase in the s...

  17. LANDFILL BIOREACTOR PERFORMANCE, SECOND INTERIM REPORT

    EPA Science Inventory

    A bioreactor landfill is a landfill that is operated in a manner that is expected to increase the rate and extent of waste decomposition, gas generation, and settlement compared to a traditional landfill. This Second Interim Report was prepared to provide an interpretation of fie...

  18. BIOREACTOR DESIGN - OUTER LOOP LANDFILL, LOUISVILLE, KY

    EPA Science Inventory

    Bioreactor field demonstration projects are underway at the Outer Loop Landfill in Louisville, KY, USA. The research effort is a cooperative research effort between US EPA and Waste Management Inc. Two primary kinds of municipal waste bioreactors are under study at this site. ...

  19. MONITORING APPROACHES FOR BIOREACTOR LANDFILLS - Report

    EPA Science Inventory

    Experimental bioreactor landfill operations at operating Municipal Solid Waste (MSW) landfills can be approved under the research development and demonstration (RD&D) provisions of 30CFR 258.4. To provide a basis for consistent data collection for future decision-making in suppor...

  20. Evaluation Of Landfill Gas Decay Constant For Municipal Solid Waste Landfills Operated As Bioreactors

    EPA Science Inventory

    Prediction of the rate of gas production from bioreactor landfills is important to optimize energy recovery and to estimate greenhouse gas emissions. Landfill gas (LFG) composition and flow rate were monitored for four years for a conventional and two bioreactor landfill landfil...

  1. STATE OF THE PRACTICE FOR BIOREACTOR LANDFILLS - SUMMARY OF USEPA WORKSHOP ON BIOREACTOR LANDFILLS: SUMMARY

    EPA Science Inventory

    This is a summary of the Workshop on Landfill Bioreactors, held 9/6-7/2000 in Arlington, VA. The purpose of the workshop was to provide a forum to EPA, state and local governments, solid waste industry, and academic research representatives to exchange information and ideas on b...

  2. Bioreactor landfill technology in municipal solid waste treatment: an overview.

    PubMed

    Kumar, Sunil; Chiemchaisri, Chart; Mudhoo, Ackmez

    2011-03-01

    In recent years, due to an advance in knowledge of landfill behaviour and decomposition processes of municipal solid waste, there has been a strong thrust to upgrade existing landfill technologies for optimizing these degradation processes and thereafter harness a maximum of the useful bioavailable matter in the form of higher landfill gas generation rates. Operating landfills as bioreactors for enhancing the stabilization of wastes is one such technology option that has been recently investigated and has already been in use in many countries. A few full-scale implementations of this novel technology are gaining momentum in landfill research and development activities. The publication of bioreactor landfill research has resulted in a wide pool of knowledge and useful engineering data. This review covers leachate recirculation and stabilization, nitrogen transformation and corresponding extensive laboratory- and pilot-scale research, the bioreactor landfill concept, the benefits to be derived from this bioreactor landfill technology, and the design and operational issues and research trends that form the basis of applied landfill research.

  3. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-12-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Liquid addition has commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell and biofilter has been completed. The remaining task to be completed is to test the biofilter prior to operation, which is currently anticipated to begin in January 2004. The current project status and preliminary monitoring results are summarized in this report.

  4. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2002-04-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches while providing superior environmental protection. The overall objective is to manage landfill solid waste for rapid waste decomposition, maximum landfill gas generation and capture, and minimum long-term environmental consequences. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Construction is complete on the 3.5 acre anaerobic cell and liquid addition has commenced. Construction of the 2.5 acre aerobic cell is nearly complete with only the blower station and biofilter remaining. Waste placement and instrumentation installation is ongoing in the west-side 6-acre anaerobic cell. The current project status and preliminary monitoring results are summarized in this report.

  5. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-08-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Liquid addition has commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell is nearly complete with only the biofilter remaining and is scheduled to be complete by the end of August 2003. The current project status and preliminary monitoring results are summarized in this report.

  6. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2002-08-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Construction is complete on the 3.5-acre anaerobic cell and liquid addition has commenced. Construction of the 2.5 acre aerobic cell is nearly complete with only the blower station and biofilter remaining. Waste placement and instrumentation installation is ongoing in the west-side 6-acre anaerobic cell. The current project status and preliminary monitoring results are summarized in this report.

  7. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-05-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Construction is complete on the 3.5-acre anaerobic cell and liquid addition has commenced. Construction of the 2.5-acre aerobic cell is nearly complete with only the biofilter remaining and construction of the west-side 6-acre anaerobic cell is nearly complete with only the liquid addition system remaining. The current project status and preliminary monitoring results are summarized in this report.

  8. Full Scale Bioreactor Landfill for Carbon Sequestration and Greenhouse Emission Control

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Kathy Sananikone; Don Augenstein

    2005-03-30

    The Yolo County Department of Planning and Public Works constructed a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective was to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entailed the construction of a 12-acre module that contained a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells were highly instrumented to monitor bioreactor performance. Liquid addition commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell and biofilter has been completed. The current project status and preliminary monitoring results are summarized in this report.

  9. 40 CFR 258.41 - Project XL Bioreactor Landfill Projects.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Project XL Bioreactor Landfill Projects. 258.41 Section 258.41 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Design Criteria § 258.41 Project XL...

  10. Mill Seat Landfill Bioreactor Renewable Green Power (NY)

    SciTech Connect

    Barton & Loguidice, P.C.

    2010-01-07

    The project was implemented at the Mill Seat landfill located in the Town of Bergen, Monroe County, New York. The landfill was previously equipped with a landfill gas collection system to collect methane gas produced by the bioreactor landfill and transport it to a central location for end use. A landfill gas to energy facility was also previously constructed at the site, which utilized generator engines, designed to be powered with landfill methane gas, to produce electricity, to be utilized on site and to be sold to the utility grid. The landfill gas generation rate at the site had exceeded the capacity of the existing generators, and the excess landfill gas was therefore being burned at a candlestick flare for destruction. The funded project consisted of the procurement and installation of two (2) additional 800 KW Caterpillar 3516 generator engines, generator sets, switchgear and ancillary equipment.

  11. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2002-02-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches while providing superior environmental protection. The overall objective is to manage landfill solid waste for rapid waste decomposition, maximum landfill gas generation and capture, and minimum long-term environmental consequences. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. The current project status and preliminary monitoring results are summarized in this report.

  12. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    SciTech Connect

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2002-01-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches while providing superior environmental protection. The overall objective is to manage landfill solid waste for rapid waste decomposition, maximum landfill gas generation and capture, and minimum long-term environmental consequences. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. The current project status and preliminary monitoring results are summarized in this report.

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

    SciTech Connect

    Raga, Roberto; Cossu, Raffaello

    2013-04-15

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

  14. T2LBM Version 1.0: Landfill bioreactor model for TOUGH2

    SciTech Connect

    Oldenburg, Curtis M.

    2001-05-22

    The need to control gas and leachate production and minimize refuse volume in landfills has motivated the development of landfill simulation models that can be used by operators to predict and design optimal treatment processes. T2LBM is a module for the TOUGH2 simulator that implements a Landfill Bioreactor Model to provide simulation capability for the processes of aerobic or anaerobic biodegradation of municipal solid waste and the associated flow and transport of gas and liquid through the refuse mass. T2LBM incorporates a Monod kinetic rate law for the biodegradation of acetic acid in the aqueous phase by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. Acetic acid is considered a proxy for all biodegradable substrates in the refuse. Aerobic and anaerobic microbes are assumed to be immobile and not limited by nutrients in their growth. Methane and carbon dioxide generation due to biodegradation with corresponding thermal effects are modeled. The numerous parameters needed to specify biodegradation are input by the user in the SELEC block of the TOUGH2 input file. Test problems show that good matches to laboratory experiments of biodegradation can be obtained. A landfill test problem demonstrates the capabilities of T2LBM for a hypothetical two-dimensional landfill scenario with permeability heterogeneity and compaction.

  15. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    PubMed Central

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-01-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g−1 COD and methane percentages of 53–76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L−1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg−1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L−1 d−1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68–95 fmol N cell−1 d−1, which finally led to the stable operation of the system. PMID:27279481

  16. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    NASA Astrophysics Data System (ADS)

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-06-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g‑1 COD and methane percentages of 53–76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L‑1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg‑1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L‑1 d‑1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68–95 fmol N cell‑1 d‑1, which finally led to the stable operation of the system.

  17. Permitting of Landfill Bioreactor Operations: Ten Years after ...

    EPA Pesticide Factsheets

    Prior to promulgation of the Rule, there were approximately 20 full-scale bioreactor projects in North America, including one in Canada. Of these, six were permitted by EPA (four Project XL sites and two projects listed separately under a cooperative research agreement at the Outer Loop Landfill in Kentucky). In March 2014, there were about 40 bioreactor projects reported, including 30 active RD&D projects in 11 approved states and one project on tribal lands. Wisconsin features the largest number of projects at 13, due primarily to the fact that landfill owners in the state must either eliminate landfill disposal of biodegradable materials or to achieve the complete stabilization of deposited organic waste at MSW landfills within 40 years after closure. Most landfill operators have selected a bioreactor approach to attempt to achieve the latter goal. In summary, only 16 of 50 (32%) states have currently adopted the Rule, meaning that development of RD&D permitting procedures that are consistent with EPA’s requirements has generally not occurred. The predominant single reason cited for not adopting the Rule was lack of interest amongst landfill facilities in the state. Subtitle D and its state derivatives already allow leachate recirculation over prescriptive (i.e., minimum technology) liner systems, which is often the primary goal of site operators seeking to control leachate treatment costs. Other reasons related to concerns over increased time, cost

  18. Performance of bioreactor landfill with waste mined from a dumpsite.

    PubMed

    Karthikeyan, Obuli P; Swati, M; Nagendran, R; Joseph, Kurian

    2007-12-01

    Emissions from landfills via leachate and gas are influenced by state and stability of the organic matter in the solid waste and the environmental conditions within the landfill. This paper describes a modified, ecologically sound waste treatment technique, where municipal solid waste is anaerobically treated in a lysimeter-scale landfill bioreactor with leachate recirculation to enhance organic degradation. The results demonstrate a substantial decrease in organic matter (BOD 99%, COD 88% and TOC 81%) and a clear decrease in nutrient concentrations especially ammonia (85%) over a period of 1 year with leachate recirculation.

  19. Evaluation of landfill gas decay constant for municipal solid waste landfills operated as bioreactors.

    PubMed

    Tolaymat, Thabet M; Green, Roger B; Hater, Gary R; Barlaz, Morton A; Black, Paul; Bronson, Doug; Powell, Jon

    2010-01-01

    Prediction of the rate of gas production from bioreactor landfills is important for the optimization of energy recovery and for estimating greenhouse gas emissions. To improve the predictability of gas production, landfill gas (LFG) composition and flow rates were monitored for 4 yr from one conventional and two bioreactor landfill cells at the Outer Loop Landfill in Louisville, KY. The ultimate methane yield (L(o)) was estimated from the biochemical methane (CH4) potential of freshly buried refuse and the decay rate constant (k) was estimated from measured CH4 collection. The site-specific L(o) was estimated to be 48.4 m3-CH4 wet Mg(-1). The estimated decay rate in the conventional cell (0.06 yr(-1)) was comparable to the AP-42 default value of 0.04 yr(-1), whereas estimates for the two bioreactor cells were substantially higher (approximately 0.11 yr(-1)). The data document the ability of the bioreactor operation to enhance landfill CH4 generation, although the estimated decay rate is sensitive to the selected L(o). The more rapid decomposition in the bioreactor cells reduces the length of time over which gas will be produced and emphasizes the importance of having a LFG collection system operational once the waste receives added moisture.

  20. MEASUREMENT OF FUGITIVE EMISSIONS AT A BIOREACTOR LANDFILL

    EPA Science Inventory

    This report focuses on three field campaigns performed in 2002 and 2003 to measure fugitive emissions at a bioreactor landfill in Louisville, KY, using an open-path Fourier transform infrared spectrometer. The study uses optical remote sensing-radial plume mapping. The horizontal...

  1. Pilot-scale nitrogen removal from leachate by ex situ nitrification and in situ denitrification in a landfill bioreactor.

    PubMed

    Sun, Faqian; Sun, Bin; Li, Qian; Deng, Xiaoya; Hu, Jian; Wu, Weixiang

    2014-04-01

    A combined process consisting of ex situ nitrification and in situ denitrification in landfill refuse was studied in pilot scale for nitrogen removal from municipal landfill leachate. The results showed that above 80% of partial nitrification ratio and an average COD loading rate of 1.50 kg m(-3) d(-1) were steadily maintained under DO concentrations of 1.0-1.7 mg L(-1) in the aerobic reactor. Quantitative PCR results indicated that nitrite-oxidizing bacteria being sensitive to DO fluctuations lead to partial nitrification when free ammonia inhibition was weak. Nitrified landfill leachate could be denitrified in the landfill bioreactor with maximum total oxidizing nitrogen removal rate of 67.2 g N t(-1) TSwaste d(-1). Clone and sequencing analysis of denitrifying bacterial nirS gene inferred that heterotrophic denitrifier Azoarcus tolulyticu was the primary nitrogen converter in the landfill bioreactor. The obtained results will provide valuable information for optimizing the design and operation of a landfill bioreactor.

  2. Multiphase Modeling of Flow, Transport, and Biodegradation in a Mesoscale Landfill Bioreactor

    SciTech Connect

    Oldenburg, Curtis M.; Borglin, Sharon E.; Hazen, Terry C.

    2002-02-01

    The need to control gas and leachate production and minimize refuse volume in municipal solid waste landfills has motivated the development of landfill simulation models to predict and design optimal treatment processes. We have developed a multiphase and multicomponent nonisothermal module called T2LBM for the three-dimensional TOUGH2 flow and transport simulator. T2LBM can be used to simulate aerobic or anaerobic biodegradation of municipal solid waste and the associated flow and transport of gas and liquid through the refuse mass. Acetic acid is used as a proxy for all biodegradable substrates in the refuse. T2LBM incorporates a Monod kinetic rate law for the biodegradation of acetic acid by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. We have verified the model against published data, and applied it to our own mesoscale laboratory aerobic landfill bioreactor experiments. We observe spatial variability of flow and biodegradation consistent with permeability heterogeneity and the geometry of the radial grid. The model is capable of matching results of a shut-in test where the respiration of the system is measured over time.

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

    PubMed

    Raga, Roberto; Cossu, Raffaello

    2013-04-01

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

  4. Influence of temperature on carbon and nitrogen dynamics during in situ aeration of aged waste in simulated landfill bioreactors.

    PubMed

    Tong, Huanhuan; Yin, Ke; Giannis, Apostolos; Ge, Liya; Wang, Jing-Yuan

    2015-09-01

    The effect of temperature on carbon and nitrogen compounds during in situ aeration of aged waste was investigated in lab-scale simulated landfill bioreactors at 35, 45 and 55 °C, respectively. The bioreactor operated at 55 °C presented the highest carbon mineralization rate in the initial stage, suggesting accelerated biodegradation rates under thermophilic conditions. The nitrogen speciation study indicated that organic nitrogen was the dominant species of total N in aerobic bioreactors due to ammonia removal. Leachate organic nitrogen was further fractionated to elucidate the fate of individual constituent. Detailed investigation revealed the higher bioconversion rates of N-humic and N-fulvic compounds compared to hydrophilic compounds in thermophilic conditions. At the end, waste material in 55 °C bioreactor was richer in highly matured humic substances (HS) verifying the high bioconversion rates.

  5. Bioreactor Landfill Research and Demonstration Project Northern Oaks Landfill, Harrison, MI

    SciTech Connect

    Zhao, Xiando; Voice, Thomas; and Hashsham, Syed A.

    2006-08-29

    A bioreactor landfill cell with 1.2-acre footprint was constructed, filled, operated, and monitored at Northern Oaks Recycling and Disposal Facility (NORDF) at Harrison, MI. With a filled volume of 74,239 cubic yards, the cell contained approximately 35,317 tons of municipal solid waste (MSW) and 20,777 tons of cover soil. It was laid on the slope of an existing cell but separated by a geosynthetic membrane liner. After the cell reached a design height of 60 feet, it was covered with a geosynthetic membrane cap. A three-dimensional monitoring system to collect data at 48 different locations was designed and installed during the construction phase of the bioreactor cell. Each location had a cluster of monitoring devices consisting of a probe to monitor moisture and temperature, a leachate collection basin, and a gas sampling port. An increase in moisture content of the MSW in the bioreactor cell was achieved by pumping leachate collected on-site from various other cells, as well as recirculation of leachate from the bioreactor landfill cell itself. Three types of leachate injection systems were evaluated in this bioreactor cell for their efficacy to distribute pumped leachate uniformly: a leachate injection pipe buried in a 6-ft wide horizontal stone mound, a 15-ft wide geocomposite drainage layer, and a 60-ft wide geocomposite drainage layer. All leachate injection systems were installed on top of the compacted waste surface. The distribution of water and resulting MSW moisture content throughout the bioreactor cell was found to be similar for the three designs. Water coming into and leaving the cell (leachate pumped in, precipitation, snow, evaporation, and collected leachate) was monitored in order to carry out a water balance. Using a leachate injection rate of 26 – 30 gal/yard3, the average moisture content increased from 25% to 35% (wet based) over the period of this study. One of the key aspects of this bioreactor landfill study was to evaluate bioreactor

  6. Modeling of leachate recirculation using vertical wells in bioreactor landfills.

    PubMed

    Feng, Shi-Jin; Cao, Ben-Yi; Zhang, Xu; Xie, Hai-Jian

    2015-06-01

    Leachate recirculation (LR) in municipal solid waste (MSW) landfills operated as bioreactors offers significant economic and environmental benefits. The subsurface application method of vertical wells is one of the most common LR techniques. The objective of this study was to develop a novel two-dimensional model of leachate recirculation using vertical wells. This novel method can describe leachate flow considering the effects of MSW settlement while also accounting separately for leachate flow in saturated and unsaturated zones. In this paper, a settlement model for MSW when considering the effects of compression and biodegradation on the MSW porosity was adopted. A numerical model was proposed using new governing equations for the saturated and unsaturated zones of a landfill. The following design parameters were evaluated by simulating the recirculated leachate volume and the influence zones of waste under steady-state flow conditions: (1) the effect of MSW settlement, (2) the effect of the initial void ratio, (3) the effect of the injected head, (4) the effect of the unit weight, (5) the effect of the biodegradation rate, and (6) the effect of the compression coefficient. The influence zones of LR when considering the effect of MSW settlement are smaller than those when neglecting the effect. The influence zones and LR volume increased with an increase in the injection pressure head and initial void ratio of MSW. The proposed method and the calculation results can provide important insight into the hydrological behavior of bioreactor landfills.

  7. Use of aged refuse-based bioreactor/biofilter for landfill leachate treatment.

    PubMed

    Hassan, Muhammad; Xie, Bing

    2014-08-01

    Sanitary landfilling is a proven way for disposal of municipal solid waste (MSW) in developed countries in general and in developing countries in particular, owing to its low immediate costs. On the other hand, landfilling is a matter of concern due to its generation of heavily polluted leachate. Landfill leachate becomes more refractory with time and is very difficult to treat using conventional biological processes. The aged refuse-based bioreactor/biofilter (ARB) has been shown to be a promising technology for the removal of various pollutants from landfill leachate and validates the principle of waste control by waste. Based on different environmental and operational factors, many researchers have reported remarkable pollutant removal efficiencies using ARB. This paper gives an overview of various types of ARBs used; their efficiencies; and certain factors like temperatures, loading rates, and aerobic/anaerobic conditions which affect the performance of ARBs in eliminating pollutants from leachate. Treating leachate by ARBs has been proved to be more cost-efficient, environment friendly, and simple to operate than other traditional biological techniques. Finally, future research and developments are also discussed.

  8. THE ROLE OF QUALITY ASSURANCE IN THE EVALUTION OF TWO LANDFILL BIOREACTOR OPERATIONAL TECHNIQUES AT AN EXISTING LANDFILL

    EPA Science Inventory

    A Quality Assurance Project Plan (QAPP) was prepared to document the primary objectives and data collection and interpretation efforts for two landfill bioreactor studies at the Outer Loop Landfill in Louisville, KY, operated by Waste Management, Inc. WMI). The two multi-year stu...

  9. QUALITY ASSURANCE AND SYSTEMATIC PLANNING FOR THE EVALUATION OF TWO LANDFILL BIOREACTOR OPERATIONAL TECHNIQUES AT AN EXISTING LANDFILL

    EPA Science Inventory

    A Quality Assurance Project Plan (QAPP) was prepared to document the primary objectives and data collection and interpretation efforts for two landfill bioreactor studies at the Outer Loop Landfill in Louisville, KY, operated by Waste Management, Inc. WMI). The two multi-year stu...

  10. Effects of exogenous aerobic bacteria on methane production and biodegradation of municipal solid waste in bioreactors.

    PubMed

    Ge, Sai; Liu, Lei; Xue, Qiang; Yuan, Zhiming

    2016-09-01

    Landfill is the most common and efficient ways of municipal solid waste (MSW) disposal and the landfill biogas, mostly methane, is currently utilized to generate electricity and heat. The aim of this work is to study the effects and the role of exogenous aerobic bacteria mixture (EABM) on methane production and biodegradation of MSW in bioreactors. The results showed that the addition of EABM could effectively enhance hydrolysis and acidogenesis processes of MSW degradation, resulting in 63.95% reduction of volatile solid (VS), the highest methane production rate (89.83Lkg(-1) organic matter) ever recorded and a threefold increase in accumulative methane production (362.9L) than the control (127.1L). In addition, it is demonstrated that white-rot fungi (WRF) might further promote the methane production through highly decomposing lignin, but the lower pH value in leachate and longer acidogenesis duration may cause methane production reduced. The data demonstrated that methane production and biodegradation of MSW in bioreactors could be significantly enhanced by EABM via enhanced hydrolysis and acidogenesis processes, and the results are of great economic importance for the future design and management of landfill.

  11. Pilot-scale experiment on anaerobic bioreactor landfills in China

    SciTech Connect

    Jiang, Jianguo Yang, Guodong; Deng, Zhou; Huang, Yunfeng; Huang, Zhonglin; Feng, Xiangming; Zhou, Shengyong; Zhang, Chaoping

    2007-07-01

    Developing countries have begun to investigate bioreactor landfills for municipal solid waste management. This paper describes the impacts of leachate recirculation and recirculation loadings on waste stabilization, landfill gas (LFG) generation and leachate characteristics. Four simulated anaerobic columns, R1-R4, were each filled with about 30 tons of waste and recirculated weekly with 1.6, 0.8 and 0.2 m{sup 3} leachate and 0.1 m{sup 3} tap water. The results indicated that the chemical oxygen demand (COD) half-time of leachate from R1 was about 180 days, which was 8-14 weeks shorter than that of R2-R4. A large amount of LFG was first produced in R1, and its generation rate was positively correlated to the COD or volatile fatty acid concentrations of influent leachates after the 30th week. By the 50th week of recirculation, the waste in R1 was more stabilized, with 931.2 kg COD or 175.6 kg total organic carbon released and with the highest landfill gas production. However, this contributed mainly to washout by leachate, which also resulted in the reduction of LFG generation potential and accumulation of ammonia and/or phosphorus in the early stage. Therefore, the regimes of leachate recirculation should be adjusted to the phases of waste stabilization to enhance efficiency of energy recovery. Integrated with the strategy of in situ leachate management, extra pre-treatment or post-treatment methods to remove the nutrients are recommended.

  12. PERFORMANCE OF NORTH AMERICAN BIOREACTOR LANDFILLS: II. CHEMICAL AND BIOLOGICAL CHARACTERISTICS

    EPA Science Inventory

    The objective of this research was to examine the performance of five North American bioreactor landfills. This paper represents the second of a two part series and addresses biological and chemical aspects of bioreactor performance including gas production and management, and l...

  13. STEADY-STATE DESIGN OF VERTICAL WELLS FOR LIQUIDS ADDITION AT BIOREACTOR LANDFILLS

    EPA Science Inventory

    This paper presents design charts that a landfill engineer can use for the design of a vertical well system for liquids addition at bioreactor landfills. The flow rate and lateral and vertical zones of impact of a vertical well were estimated as a function of input variables su...

  14. Stripping/flocculation/membrane bioreactor/reverse osmosis treatment of municipal landfill leachate.

    PubMed

    Hasar, Halil; Unsal, Sezahat A; Ipek, Ubeyde; Karatas, Serdar; Cinar, Ozer; Yaman, Cevat; Kinaci, Cumali

    2009-11-15

    This study presents a configuration for the complete treatment of landfill leachate with high organic and ammonium concentrations. Ammonia stripping is performed to overcome the ammonia toxicity to aerobic microorganisms. By coagulation-flocculation process, COD and suspended solids (SS) were removed 36 and 46%, respectively. After pretreatment, an aerobic/anoxic membrane bioreactor (Aer/An MBR) accomplished the COD and total inorganic nitrogen (total-N(i)) removals above 90 and 92%, respectively, at SRT of 30 days. Concentrations of COD and total-N(i) (not considering organic nitrogen) in the Aer/An MBR effluent decreased to 450 and 40 mg/l, respectively, by significant organic oxidation and nitrification/denitrification processes. As an advanced treatment for the leachate, the reverse osmosis (RO) was applied to the collected Aer/An MBR effluents. Reverse osmosis provided high quality effluent by reducing the effluent COD from MBR to less than 4.0mg/l at SRT of 30 days.

  15. Heavy metals mobility in full-scale bioreactor landfill: initial stage.

    PubMed

    Qu, Xian; He, Pin-Jing; Shao, Li-Ming; Lee, Duu-Jong

    2008-01-01

    Selected heavy metals (HMs) including Cd, Cr, Cu, Ni, Pb and Zn initially released from a full-scale bioreactor landfill were monitored over the first 20 months of operation. At the initial landfill stage, the leachate exhibited high HMs release, high organic matter content (27000-43000gl(-1) of TOC) and low pH (5-6). By the fifth month of landfilling, the methanogenic stage had been established, and HMs release was reduced below the Chinese National Standards. Total released HMs accounted for less than 1% of landfill deposited during the investigated period. Most landfill HMs were inorganic. Fourier-transform infrared (FT-IR) spectra data and model calculations using Visual MINTEQ indicated that humic substances strongly affected the mobility of organic fractions of HMs in the methanogenic landfill. The initial rates of HMs release could be enhanced by recycling the leachate back to bioreactor landfill, but the total quantity released may be reduced by early establishment of methanogenic stage in bioreactor landfill.

  16. Field assessment of semi-aerobic condition and the methane correction factor for the semi-aerobic landfills provided by IPCC guidelines.

    PubMed

    Jeong, Sangjae; Nam, Anwoo; Yi, Seung-Muk; Kim, Jae Young

    2015-02-01

    According to IPCC guidelines, a semi-aerobic landfill site produces one-half of the amount of CH4 produced by an equally-sized anaerobic landfill site. Therefore categorizing the landfill type is important on greenhouse gas inventories. In order to assess semi-aerobic condition in the sites and the MCF value for semi-aerobic landfill, landfill gas has been measured from vent pipes in five semi-aerobically designed landfills in South Korea. All of the five sites satisfied requirements of semi-aerobic landfills in 2006 IPCC guidelines. However, the ends of leachate collection pipes which are main entrance of air in the semi-aerobic landfill were closed in all five sites. The CH4/CO2 ratio in landfill gas, indicator of aerobic and anaerobic decomposition, ranged from 1.08 to 1.46 which is higher than the values (0.3-1.0) reported for semi-aerobic landfill sites and is rather close to those (1.0-2.0) for anaerobic landfill sites. The low CH4+CO2% in landfill gas implied air intrusion into the landfill. However, there was no evidence that air intrusion has caused by semi-aerobic design and operation. Therefore, the landfills investigated in this study are difficult to be classified as semi-aerobic landfills. Also MCF of 0.5 may significantly underestimate methane emissions compared to other researches. According to the carbon mass balance analyses, the higher MCF needs to be proposed for semi-aerobic landfills. Consequently, methane emission estimate should be based on field evaluation for the semi-aerobically designed landfills.

  17. Removal of organic micro-pollutants from solid waste landfill leachate in membrane bioreactor operated without excess sludge discharge.

    PubMed

    Boonyaroj, V; Chiemchaisri, C; Chiemchaisri, W; Yamamoto, K

    2012-01-01

    Two-stage membrane bioreactor (MBR) system was applied to the treatment of landfill leachate from a solid waste disposal site in Thailand. The first stage anoxic reactor was equipped with an inclined tube module for sludge separation. It was followed by an aerobic stage with a hollow fiber membrane module for solid liquid separation. Mixed liquor sludge from the aerobic reactor was re-circulated back to anoxic reactor in order to maintain constant mixed liquor suspended solids (MLSS) concentration in the aerobic reactor. The removal of micro-pollutants from landfill leachate along the treatment period of 300 days was monitored. The results indicated that two-stage MBRs could remove biochemical oxygen demand (BOD), chemical oxygen demand (COD) and NH(4)(+) by 97, 87 and 91% at steady operating condition. Meanwhile organic micro-pollutant removals were 50-76%. The removal efficiencies varied according to the hydrophobic characteristic of compounds but they were improved during long-term MBR operation without sludge discharge.

  18. Field assessment of semi-aerobic condition and the methane correction factor for the semi-aerobic landfills provided by IPCC guidelines

    SciTech Connect

    Jeong, Sangjae; Nam, Anwoo; Yi, Seung-Muk; Kim, Jae Young

    2015-02-15

    Highlights: • CH{sub 4}/CO{sub 2} and CH{sub 4} + CO{sub 2}% are proposed as indices to evaluate semi-aerobic landfills. • A landfill which CH{sub 4}/CO{sub 2} > 1.0 is difficult to be categorized as semi-aerobic landfill. • Field conditions should be carefully investigated to determine landfill types. • The MCF default value for semi-aerobic landfills underestimates the methane emissions. - Abstract: According to IPCC guidelines, a semi-aerobic landfill site produces one-half of the amount of CH{sub 4} produced by an equally-sized anaerobic landfill site. Therefore categorizing the landfill type is important on greenhouse gas inventories. In order to assess semi-aerobic condition in the sites and the MCF value for semi-aerobic landfill, landfill gas has been measured from vent pipes in five semi-aerobically designed landfills in South Korea. All of the five sites satisfied requirements of semi-aerobic landfills in 2006 IPCC guidelines. However, the ends of leachate collection pipes which are main entrance of air in the semi-aerobic landfill were closed in all five sites. The CH{sub 4}/CO{sub 2} ratio in landfill gas, indicator of aerobic and anaerobic decomposition, ranged from 1.08 to 1.46 which is higher than the values (0.3–1.0) reported for semi-aerobic landfill sites and is rather close to those (1.0–2.0) for anaerobic landfill sites. The low CH{sub 4} + CO{sub 2}% in landfill gas implied air intrusion into the landfill. However, there was no evidence that air intrusion has caused by semi-aerobic design and operation. Therefore, the landfills investigated in this study are difficult to be classified as semi-aerobic landfills. Also MCF of 0.5 may significantly underestimate methane emissions compared to other researches. According to the carbon mass balance analyses, the higher MCF needs to be proposed for semi-aerobic landfills. Consequently, methane emission estimate should be based on field evaluation for the semi-aerobically designed landfills.

  19. Old landfill leachate treatment through multistage process: membrane adsorption bioreactor and nanofitration.

    PubMed

    Peyravi, Majid; Jahanshahi, Mohsen; Alimoradi, Mahsa; Ganjian, Etesam

    2016-12-01

    A bench-scale integrated process based on submerged aerobic powdered activated carbon-membrane bioreactor (PAC-MBR) has been utilized and established for the treatment of landfill leachate. The results showed that the submerged PAC-MBR system effectively removed biodegradable trace organic compounds by the average removal rate about 71 % at optimum food to microorganism (F/M) ratio of 0.4 gCOD/g day under a HRT of 24 h. Adding nanofiltration (NF) process increased the treatment efficiency up to 99 %. Further, adding powdered activated carbon to activated sludge (AS) resulted in a higher adsorption capacity in comparison with AS. Adsorption isotherms were investigated and fitted by the Langmuir and Freundlich isotherm models in which the Langmuir model performed better. The specific oxygen uptake rate (SOUR) showed that adding PAC reduces the effects of COD on microorganism activities. NH3-N, TKN and Heavy metals removal efficiency amounted to 97 ± 2, 96 ± 2, and 99 ± 2 %, respectively.

  20. Aerobic biological treatment of leachates from municipal solid waste landfill.

    PubMed

    Andrés, P; Gutierrez, F; Arrabal, C; Cortijo, M

    2004-01-01

    The main objective of the study was to improve chemical oxygen demand (COD) elimination by secondary biological treatment from leachate of municipal solid waste landfill. This effluent was a supernatant liquid obtained after physicochemical processes and coagulating with Al3+ followed by ammoniacal stripping. First, respirometric assays were carried out to determine the substrate biodegradability. Specific sludge respiration rate (R(s)) vs. concentration of substrate (S), showed an increasing specific rate of assimilation of substrate (Rs), which reached the highest value, when the substrate concentration (COD) was between 75 and 200 mg O2 L(-1). Second, continuous experiments were made in an aerobic digester to test the previous respirometric data and the results showed removal efficiency of COD between 83 and 69%, and a substrate assimilation rate between 1.3 and 3.1 g COD g(-1) volatile suspended solids d(-1).

  1. PERFORMANCE OF NORTH AMERICAN BIOREACTOR LANDFILLS: I. LEACHATE HYDROLOGY AND WASTE SETTLEMENT

    EPA Science Inventory

    An assessment of state-of-the-practice at five full-scale North American landfills operating as bioreactors is presented in this two-paper set. This paper focuses on effectiveness of liners and leachate collection systems, leachate generation rates, leachate recirculation practi...

  2. Full-scale leachate-recirculating MSW landfill bioreactor assessments

    SciTech Connect

    Carson, D.A.

    1995-10-01

    The integrated waste management hierarchy philosophy continues to develop as a useful tool to solve solid waste issues in an environmentally responsible manner. Recent statistics indicate that approximately two thirds of municipal solid waste in the United States is disposed in landfills. Current landfill operational technique involves the preparation of a waste containment facility, the filling of the waste unit, installation of the final cover, and the maintenance of the unit. This method of operation has proven to be reasonably effective in waste disposal, effectively minimizing risk by collecting the liquid that percolates through the waste, called leachates, at the bottom of the landfill, and controlling landfill gas with collection systems. Concerns over the longevity of containment systems components present questions that cannot be answered without substantial performance data. Landfills, as currently operated, serve to entomb dry waste. Therefore, the facility must be maintained in perpetuity, consuming funds and ultimately driving up waste collection costs. This presentation will describe a new form of solid waste landfill operation, it is a technique that involves controlled natural processes to break down landfilled waste, and further minimize risk to human health and the environment. A landfill operated in an active manner will encourage and control natural decomposition of landfilled waste. This can be accomplished by collecting leachate, and reinjecting it into the landfilled waste mass. Keeping the waste mass moist will lead to a largely anaerobic system with the capacity to rapidly stabilize the landfilled waste mass via physical, chemical and biological methods. The system has proven the ability to breakdown portions of the waste mass, and to degrade toxic materials at the laboratory scale.

  3. COD fractions of leachate from aerobic and anaerobic pilot scale landfill reactors.

    PubMed

    Bilgili, M Sinan; Demir, Ahmet; Akkaya, Ebru; Ozkaya, Bestamin

    2008-10-01

    One of the most important problems with designing and maintaining a landfill is managing leachate that generated when water passes through the waste. In this study, leachate samples taken from aerobic and anaerobic landfill reactors operated with and without leachate recirculation are investigated in terms of biodegradable and non-biodegradable fractions of COD. The operation time is 600 days for anaerobic reactors and 250 days for aerobic reactors. Results of this study show that while the values of soluble inert COD to total COD in the leachate of aerobic landfill with leachate recirculation and aerobic dry reactors are determined around 40%, this rate was found around 30% in the leachate of anaerobic landfill with leachate recirculation and traditional landfill reactors. The reason for this difference is that the aerobic reactors generated much more microbial products. Because of this condition, it can be concluded that total inert COD/total COD ratios of the aerobic reactors were 60%, whereas those of anaerobic reactors were 50%. This study is important for modeling, design, and operation of landfill leachate treatment systems and determination of discharge limits.

  4. MATHEMATICAL MODEL FOR METHANE PRODUCTION FROM LANDFILL BIOREACTOR - A DISCUSSION PAPER HTTP://OIPS.AIP.ORG/EEO/

    EPA Science Inventory

    This discussion explains the experimental results of a landfill bioreactor (LFBR) from a microbiological perspective and provides a feasible strategy to evaluate methane production performance, since suitable models are complicated and not sufficiently reliable for anaerobic-syst...

  5. Slope stability of bioreactor landfills during leachate injection: effects of heterogeneous and anisotropic municipal solid waste conditions.

    PubMed

    Giri, Rajiv K; Reddy, Krishna R

    2014-03-01

    In bioreactor landfills, leachate recirculation can significantly affect the stability of landfill slope due to generation and distribution of excessive pore fluid pressures near side slope. The current design and operation of leachate recirculation systems do not consider the effects of heterogeneous and anisotropic nature of municipal solid waste (MSW) and the increased pore gas pressures in landfilled waste caused due to leachate recirculation on the physical stability of landfill slope. In this study, a numerical two-phase flow model (landfill leachate and gas as immiscible phases) was used to investigate the effects of heterogeneous and anisotropic nature of MSW on moisture distribution and pore-water and capillary pressures and their resulting impacts on the stability of a simplified bioreactor landfill during leachate recirculation using horizontal trench system. The unsaturated hydraulic properties of MSW were considered based on the van Genuchten model. The strength reduction technique was used for slope stability analyses as it takes into account of the transient and spatially varying pore-water and gas pressures. It was concluded that heterogeneous and anisotropic MSW with varied unit weight and saturated hydraulic conductivity significantly influenced the moisture distribution and generation and distribution of pore fluid pressures in landfill and considerably reduced the stability of bioreactor landfill slope. It is recommended that heterogeneous and anisotropic MSW must be considered as it provides a more reliable approach for the design and leachate operations in bioreactor landfills.

  6. Compartment model of aerobic and anaerobic biodegradation in a municipal solid waste landfill.

    PubMed

    Kim, Sang-Yul; Tojo, Yasumasa; Matsuto, Toshihiko

    2007-12-01

    The mathematical formulations in a one-dimensional compartment model of the biodegradation of organic landfill components are described. The model is designed to switch between anaerobic and aerobic conditions, depending on the local oxygen concentration. The model also includes the effect of environmental factors, such as moisture content, pH, and temperature, on reaction rates. The model includes not only biodegradation processes for carbon compounds (acetate, CO2, CH4), but also for nitrogen compounds involved in nitrification and denitrification due to their significance in landfills. Two example runs to simulate anaerobic and aerobic waste were conducted for a single landfill unit cell by changing the organic content and diffusion coefficient.

  7. Effects of intermittent and continuous aeration on accelerative stabilization and microbial population dynamics in landfill bioreactors.

    PubMed

    Sang, Nguyen Nhu; Soda, Satoshi; Inoue, Daisuke; Sei, Kazunari; Ike, Michihiko

    2009-10-01

    Performance and microbial population dynamics in landfill bioreactors were investigated in laboratory experiments. Three reactors were operated without aeration (control reactor, CR), with cyclic 6-h aeration and 6-h non-aeration (intermittently aerated reactor, IAR), and with continuous aeration (continuously aerated reactor, CAR). Each reactor was loaded with high-organic solid waste. The performance of IAR was highest among the reactors up to day 90. The respective solid weight, organic matter content, and waste volume on day 90 in the CR, IAR, and CAR were 50.9, 39.1, and 47.5%; 46.5, 29.3 and 35.0%; and 69, 38, and 53% of the initial values. Organic carbon and nitrogen compounds in leachate in the IAR and the CAR showed significant decreases in comparison to those in the CR. The most probable number (MPN) values of fungal 18S rDNA in the CAR and the IAR were higher than those in the CR. Terminal restriction fragment length polymorphism analysis showed that unique and diverse eubacterial and archaeal communities were formed in the IAR. The intermittent aeration strategy was favorable for initiation of solubilization of organic matter by the aerobic fungal populations and the reduction of the acid formation phase. Then the anaerobic H(2)-producing bacteria Clostridium became dominant in the IAR. Sulfate-reducing bacteria, which cannot use acetate/sulfate but which instead use various organics/sulfate as the electron donor/acceptor were also dominant in the IAR. Consequently, Methanosarcinales, which are acetate-utilizing methanogens, became the dominant archaea in the IAR, where high methane production was observed.

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

    PubMed

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

    2004-01-01

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

  9. 40 CFR 258.41 - Project XL Bioreactor Landfill Projects.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... footprint of the landfill cell. (B) Water collected on the leak detection liner shall be monitored at least... carbon; (H) Nutrients, (including ammonia , total kjeldahl nitrogen , and total phosphorus ); (I) Common... Oxygen, Dissolved Solids, Biochemical Oxygen Demand, Chemical Oxygen Demand, Organic Carbon,...

  10. 40 CFR 258.41 - Project XL Bioreactor Landfill Projects.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... footprint of the landfill cell. (B) Water collected on the leak detection liner shall be monitored at least... carbon; (H) Nutrients, (including ammonia , total kjeldahl nitrogen , and total phosphorus ); (I) Common... Oxygen, Dissolved Solids, Biochemical Oxygen Demand, Chemical Oxygen Demand, Organic Carbon,...

  11. Pyrosequence analysis of bacterial communities in aerobic bioreactors treating polycyclic aromatic hydrocarbon-contaminated soil.

    PubMed

    Singleton, David R; Richardson, Stephen D; Aitken, Michael D

    2011-11-01

    Two aerobic, lab-scale, slurry-phase bioreactors were used to examine the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil and the associated bacterial communities. The two bioreactors were operated under semi-continuous (draw-and-fill) conditions at a residence time of 35 days, but one was fed weekly and the other monthly. Most of the quantified PAHs, including high-molecular-weight compounds, were removed to a greater extent in the weekly-fed bioreactor, which achieved total PAH removal of 76%. Molecular analyses, including pyrosequencing of 16S rRNA genes, revealed significant shifts in the soil bacterial communities after introduction to the bioreactors and differences in the abundance and types of bacteria in each of the bioreactors. The weekly-fed bioreactor displayed a more stable bacterial community with gradual changes over time, whereas the monthly-fed bioreactor community was less consistent and may have been more strongly influenced by the influx of untreated soil during feeding. Phylogenetic groups containing known PAH-degrading bacteria previously identified through stable-isotope probing of the untreated soil were differentially affected by bioreactor conditions. Sequences from members of the Acidovorax and Sphingomonas genera, as well as the uncultivated "Pyrene Group 2" were abundant in the bioreactors. However, the relative abundances of sequences from the Pseudomonas, Sphingobium, and Pseudoxanthomonas genera, as well as from a group of unclassified anthracene degraders, were much lower in the bioreactors compared to the untreated soil.

  12. Pyrosequence analysis of bacterial communities in aerobic bioreactors treating polycyclic aromatic hydrocarbon-contaminated soil

    PubMed Central

    Richardson, Stephen D.; Aitken, Michael D.

    2011-01-01

    Two aerobic, lab-scale, slurry-phase bioreactors were used to examine the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil and the associated bacterial communities. The two bioreactors were operated under semi-continuous (draw-and-fill) conditions at a residence time of 35 days, but one was fed weekly and the other monthly. Most of the quantified PAHs, including high-molecular-weight compounds, were removed to a greater extent in the weekly-fed bioreactor, which achieved total PAH removal of 76%. Molecular analyses, including pyrosequencing of 16S rRNA genes, revealed significant shifts in the soil bacterial communities after introduction to the bioreactors and differences in the abundance and types of bacteria in each of the bioreactors. The weekly-fed bioreactor displayed a more stable bacterial community with gradual changes over time, whereas the monthly-fed bioreactor community was less consistent and may have been more strongly influenced by the influx of untreated soil during feeding. Phylogenetic groups containing known PAH-degrading bacteria previously identified through stable-isotope probing of the untreated soil were differentially affected by bioreactor conditions. Sequences from members of the Acidovorax and Sphingomonas genera, as well as the uncultivated ‘‘Pyrene Group 2’’ were abundant in the bioreactors. However, the relative abundances of sequences from the Pseudomonas, Sphingobium, and Pseudoxanthomonas genera, as well as from a group of unclassified anthracene degraders, were much lower in the bioreactors compared to the untreated soil. PMID:21369833

  13. Influence of supplemental heat addition on performance of pilot-scale bioreactor landfills.

    PubMed

    Abdallah, Mohamed; Kennedy, Kevin; Narbaitz, Roberto; Warith, Mostafa; Sartaj, Majid

    2014-02-01

    Implementation of supplemental heat addition as a means of improving bioreactor landfill performance was investigated. The experimental work was conducted with two pilot-scale bioreactor setups (control cell and heated cell) operated for 280 days. Supplemental heat was introduced by recirculating leachate heated up to 35 °C compared to the control which used similar quantities of leachate at room temperature (21 ± 1 °C). The temporal and spatial effects of recirculating heated leachate on the landfill internal temperature were determined, and performance was assessed in terms of leachate parameters and biogas production. Recirculation of heated leachate helped establish balanced anaerobic microbial consortia that led to earlier (70 days) and greater (1.4-fold) organic matter degradation rates, as well as threefold higher methane production compared to the non-heated control. Despite the significant enhancements in performance resulting from supplemental heat addition, heated leachate recirculation did not significantly impact waste temperatures, and the effects were mainly restricted to short periods after recirculation and mostly at the upper layers of the waste. These findings suggest that improvements in bioreactor landfill performance may be achieved without increasing the temperature of the whole in-place waste, but rather more economically by raising the temperature at the leachate/waste interface which is also exposed to the maximum moisture levels within the waste matrix.

  14. A comparison of nanosilver and silver ion effects on bioreactor landfill operations and methanogenic population dynamics.

    PubMed

    Yang, Yu; Gajaraj, Shashikanth; Wall, Judy D; Hu, Zhiqiang

    2013-06-15

    Silver nanoparticles (AgNPs, nanosilver) and silver ions released from industry and various consumer products are eventually disposed in sanitary landfills. To compare the effects of these two forms of silver on landfill bioreactor operations with leachate recirculation, municipal solid waste (MSW) in six identical 9-L bioreactors was exposed to AgNPs (stabilized with 0.06% polyvinyl alcohol) or Ag(+) at a silver concentration of 10 mg/kg solids. The landfill anaerobic digestion was operated and monitored for more than 200 days. There was no significant difference in cumulative methane volume or methane production rate between the groups of control and 10 mg/kg Ag(+). However, MSW treated with 10 mg/kg AgNPs resulted in a reduced methane production (by up to 80%) and accumulation of volatile fatty acids in the leachates. This was accompanied by higher leachate Ag concentrations (an average of 3.7 ± 0.3 mg/L) after day 132 as compared to those in the groups of control and 10 mg/kg Ag(+) at 0.7 ± 0.4 and 1.1 ± 0.3 mg/L, respectively. Quantitative PCR targeting 16S rRNA genes of methanogens indicated reduced methanogenic growth in the bioreactors exposed to nanosilver. The peak values of total methanogens in leachates were (1.18 ± 0.09) × 10(10), (4.57 ± 2.67) × 10(10) and (7.72 ± 0.78) × 10(8) (cells/mL) for the groups of control, Ag(+) and AgNPs, respectively. The results suggest that silver ions have minimal impact on landfill methane production at the concentration of 10 mg/kg. However, nanosilver inhibits methanogenesis and is more toxic than its counterpart, likely due to slow and long-term Ag(+) release from nanosilver dissolution yielding more bioavailability in landfill leachates.

  15. Performance evaluation of the bioreactor landfill in treatment and stabilisation of mechanically biologically treated municipal solid waste.

    PubMed

    Lakshmikanthan, P; Sivakumar Babu, G L

    2017-03-01

    The potential of bioreactor landfills to treat mechanically biologically treated municipal solid waste is analysed in this study. Developing countries like India and China have begun to investigate bioreactor landfills for municipal solid waste management. This article describes the impacts of leachate recirculation on waste stabilisation, landfill gas generation, leachate characteristics and long-term waste settlement. A small-scale and large-scale anaerobic cell were filled with mechanically biologically treated municipal solid waste collected from a landfill site at the outskirts of Bangalore, India. Leachate collected from the same landfill site was recirculated at the rate of 2-5 times a month on a regular basis for 370 days. The total quantity of gas generated was around 416 L in the large-scale reactor and 21 L in the small-scale reactor, respectively. Differential settlements ranging from 20%-26% were observed at two different locations in the large reactor, whereas 30% of settlement was observed in the small reactor. The biological oxygen demand/chemical oxygen demand (COD) ratio indicated that the waste in the large reactor was stabilised at the end of 1 year. The performance of the bioreactor with respect to the reactor size, temperature, landfill gas and leachate quality was analysed and it was found that the bioreactor landfill is efficient in the treatment and stabilising of mechanically biologically treated municipal solid waste.

  16. LANDFILLS AS BIOREACTORS: RESEARH AT THE OUTER LOOP LANDFILL, LOUISVILLE, KENTUCKY; FIRST INTERIM REPORT

    EPA Science Inventory

    Interim report resulting from a cooperative research and development agreement (CRADA) between US EP A's Officeof Research and Development - National Risk Management Research Laboratory and a n ongoing field demonstration
    of municipal waste landfills being operated as bioreact...

  17. Quality and Quantity of Leachate in Aerobic Pilot-Scale Landfills

    NASA Astrophysics Data System (ADS)

    Bilgili, Memmet Sinan; Demir, Ahmet; Özkaya, Bestamin

    2006-08-01

    In this study, two pilot-scale aerobic landfill reactors with (A1) and without (A2) leachate recirculation are used to obtain detailed information on the quantity and quality of leachate in aerobic landfills. The observed parameters of leachate quality are pH, chloride (Cl-), chemical oxygen demand (COD), biological oxygen demand (BOD), total Kjeldahl nitrogen (TKN), ammonia nitrogen (NH3-N), and nitrate (NO3 --N). pH values of the leachate increased to 7 after 50 days in reactor A1 and after 70 days in reactor A2. Cl- concentrations increased rapidly to 6100 (A1) and 6900 (A2) mg/L after 80 days, from initial values of 3000 and 2800 mg/L, respectively. COD and BOD values decreased rapidly in the A1 landfill reactor, indicating the rapid oxidation of organic matter. The BOD/COD ratio indicates that leachate recirculation slightly increases the degradation of solid waste in aerobic landfills. NH3-N concentrations decreased as a result of the nitrification process. Denitrification occurred in parts of the reactors as a result of intermittent aeration; this process causes a decrease in NO3 - concentrations. There is a marked difference between the A1 and A2 reactors in terms of leachate quantity. Recirculated leachate made up 53.3% of the leachate generated from the A1 reactor during the experiment, while leachate quantity decreased by 47.3% with recirculation when compared with the aerobic dry landfill reactor.

  18. Treatment of phenolics, aromatic hydrocarbons, and cyanide-bearing wastewater in individual and combined anaerobic, aerobic, and anoxic bioreactors.

    PubMed

    Sharma, Naresh K; Philip, Ligy

    2015-01-01

    Studies were conducted on a mixture of pollutants commonly found in coke oven wastewater (CWW) to evaluate the biodegradation of various pollutants under anaerobic, aerobic, and anoxic conditions. The removal of the pollutants was monitored during individual bioreactor operation and using a combination of bioreactors operating in anaerobic-aerobic-anoxic sequence. While studying the performance of individual reactors, it was observed that cyanide removal (83.3 %) was predominant in the aerobic bioreactor, while much of the chemical oxygen demand (COD) (69 %) was consumed in the anoxic bioreactor. With the addition of cyanide, the COD removal efficiency was affected in all the bioreactors, and several intermediates were detected. While treating synthetic CWW using the combined bioreactor system, the overall COD removal efficiency was 86.79 % at an OLR of 2.4 g COD/L/day and an HRT of 96 h. The removal efficiency of 3,5-xylenol and cyanide, with inlet concentration of 150 and 10 mg/L, was found to be 91.8 and 93.6 % respectively. It was found that the impact of xylenol on the performance of the bioreactors was less than cyanide toxicity. Molecular analysis using T-RFLP revealed the dominance of strictly aerobic, mesophilic proteobacterium, Bosea minatitlanensis, in the aerobic bioreactor. The anoxic bioreactor was dominant with Rhodococcus pyridinivorans, known for its remarkable aromatic decomposing activity, while an unclassified Myxococcales bacterium was identified as the predominant bacterial species in the anaerobic bioreactor.

  19. Co-disposal of electronic waste with municipal solid waste in bioreactor landfills.

    PubMed

    Visvanathan, C; Visvanthan, C; Yin, Nang Htay; Karthikeyan, Obuli P

    2010-12-01

    Three pilot scale lysimeters were adopted to evaluate the stability pattern and leaching potential of heavy metals from MSW landfills under the E-waste co-disposed condition. One lysimeter served as control and solely filled with MSW, whereas the other two lysimeters were provided with 10% and 25% of E-waste scraps (% by weight), respectively. The reactors were monitored over a period of 280 days at ambient settings with continuous leachate recirculation. Stabilization pattern of carbon appears to be more than 50% in all the three lysimeters with irrespective of their operating conditions. Iron and zinc concentrations were high in leachate during bioreactor landfill operation and correlating with the TCLP leachability test results. In contrast, Pb concentration was around <0.6 mg/L, but which showed maximum leaching potential under TCLP test conditions. But, no heavy metal accumulation was found with leachate recirculation practices in lysimeters. Mobility of the metal content from the E-waste was found to be amplified with the long term disposal or stabilization within landfills. The results showed that the TCLP test cannot be completely reliable tool for measuring long-term leachability of toxic substances under landfill condition; rather landfill lysimeter studies are necessary to get the real scenario.

  20. Landfill leachate treatment by sequential membrane bioreactor and electro-oxidation processes.

    PubMed

    Zolfaghari, Mehdi; Jardak, Karama; Drogui, Patrick; Brar, Satinder Kaur; Buelna, Gerardo; Dubé, Rino

    2016-12-15

    Combination of high performance membrane bioreactor (MBR) equipped with ultrafiltration and electro-oxidation process (EOP) by boron-doped diamond electrode (BDD) was used to effectively treat highly contaminated old landfill leachate. MBR and EOP were optimized for raw and pretreated landfill leachate. Seasonal changes dramatically affected the both processes' performance, as the landfill leachate was ¾ more concentrated in winter. For MBR, organic load rate of 1.2 gCOD/L/day and sludge retention time of 80 days was considered as the optimum operating condition in which COD, TOC, NH4(+) and phosphorous removal efficiencies reached the average of 63, 35, 98 and 52%, respectively. The best performance of EOP was in current intensity of 3 A with treatment of time of 120 min. Effluent of electro-oxidation was more toxic due to the presence of radicals and organochlorinated compounds. These compounds were removed by stripping or assimilation of sludge if EOP was used as a pretreatment method. Furthermore, the energy consumption of EOP was decreased from 22 to 16 KWh/m(3) for biologically treated and raw landfill leachate, respectively.

  1. Liquid balance monitoring inside conventional, Retrofit, and bio-reactor landfill cells.

    PubMed

    Abichou, Tarek; Barlaz, Morton A; Green, Roger; Hater, Gary

    2013-10-01

    The Outer Loop landfill bioreactor (OLLB) in Louisville, KY, USA has been the site of a study to evaluate long-term bioreactor performance at a full-scale operational landfill. Three types of landfill units were studied including a conventional landfill (Control cell), a new landfill area that had an air addition and recirculation piping network installed as waste was being placed (As-Built cell), and a conventional landfill that was modified to allow for liquids recirculation (Retrofit cell). During the monitoring period, the Retrofit, Control, and As-Built cells received 48, 14, and 213LMg(-1) (liters of liquids per metric ton of waste), respectively. The leachate collection system yielded 60, 57 and 198LMg(-1) from the Retrofit, Control, and As-Built cells, respectively. The head on liner in all cells was below regulatory limits. In the Control and As-Built cells, leachate head on liner decreased once waste placement stopped. The measured moisture content of the waste samples was consistent with that calculated from the estimate of accumulated liquid by the liquid balance. Additionally, measurements on excavated solid waste samples revealed large spatial variability in waste moisture content. The degree of saturation in the Control cells decreased from 85% to 75%. The degree of saturation increased from 82% to 83% due to liquids addition in the Retrofit cells and decreased back to 80% once liquid addition stopped. In the As-Built cells, the degree of saturation increased from 87% to 97% during filling activities and then started to decrease soon after filling activities stopped to reach 92% at the end of the monitoring period. The measured leachate generation rates were used to estimate an in-place saturated hydraulic conductivity of the MSW in the range of 10(-8) to 10(-7)ms(-1) which is lower than previous reports. In the Control and Retrofit cells, the net loss in liquids, 43 and 12LMg(-1), respectively, was similar to the measured settlement of 15% and 5

  2. Seasonal and wastewater stream variation of trace organic compounds in a dairy processing plant aerobic bioreactor.

    PubMed

    Heaven, Michael W; Wild, Karl; Verheyen, Vincent; Cruickshank, Alicia; Watkins, Mark; Nash, David

    2011-09-01

    Bioreactors are often an integral part of dairy factory efforts to reduce the biological oxygen demand of their wastewater. In this study, infeed, mixed liquor and supernatant samples of an aerobic bioreactor used by a dairy factory in South-Eastern Australia were analyzed for nutrients and organic compounds using gas chromatography-mass spectrometry and physicochemical analyses. Despite different concentrations of organic inputs into the bioreactor, nutrients and trace organic compounds were reduced significantly (i.e. average concentration of trace organic compounds: infeed=1681 μg/L; mixed liquor=257 μg/L; supernatant=23 μg/L). However, during one sampling period the bioreactor was adversely affected by the organic loading. Trace organic compounds in the samples were predominantly fatty acids associated with animal products. The analyses suggest that it is possible to trace a disruptive input (i.e. infeed with high organic carbon concentrations) into an aerobic bioreactor by measuring concentrations of fatty acids or ammonia.

  3. [Application of cowl in semi-aerobic landfill and its influence in initial stage].

    PubMed

    Han, Dan; Zhao, You-cai; Xue, Bin-jie; Gao, Pin

    2009-10-15

    Enhancement of semi-aerobic landfill performance through a cowl installed on the gas ventilation pipeline using a simulated landfill box with 2 m x 1 m x 2 m in size was investigated, aiming at the maximum methane emission reduction. Influence of cowl on semi-aerobic environment formation was explored, and variety of methane and carbon dioxide concentrations at different wind speeds and mechanism of cowl operation were identified to provide information on design and improvement of semi-aerobic landfill. The results show that the cowl speeds up the semi-aerobic environment to shape, from over 50 days down to approximately 40 days, and reduces methane emission by promoting methane transformation to carbon dioxide. When the cowl is taken off suddenly during the normal operation, carbon dioxide concentration falls to 15.88% from the initial 16.67% immediately, and methane concentration increases to 16.12% from 6.14%. However, the carbon dioxide and methane concentration becomes 19.18% and 10.05%, respectively, as the cowl is taken on again. Additionally, methane emissions in the exhaust gas were monitored at different wind speeds of 2.0, 3.5, 5.0, 6.5, 8.0 m/s, and finds that the methane concentration reduces from the initial 15% to below 5% when the wind speed increases from 2 m/s to 8 m/s.

  4. Bioreactor treatment of municipal solid waste landfill leachates: characterization of organic fractions.

    PubMed

    Pelaez, Ana Isabel; Sanchez, Jesus; Almendros, Gonzalo

    2009-01-01

    Quantitative and qualitative changes in organic matter were studied at different stages of treatment in a bioreactor designed to process leachates from a municipal solid waste landfill. The particulate matter (PM) and macromolecular fractions of the dissolved organic matter with solubility properties comparable to humic (acid-insoluble) and fulvic (acid-soluble) acid fractions (AI, AS, respectively) from the incoming black liquid, the bioreactor content, and the final processed effluent were isolated, quantified, and characterized by visible and infrared (IR) spectroscopies. The macromolecular signature either aliphatic (glycopeptides, carbohydrates) or aromatic (coinciding with infrared patterns of lignin, tannins etc.) enabled us to characterize the different organic fractions during the course of microbial transformation. The results reveal significant changes in the nitrogen speciation patterns within the different organic fractions isolated from the wastewater. The final increase in the relative proportions of nitrogen in the least aromatic AS fraction during microbial transformation could be related to protein formation inside the bioreactor. After biological treatment and ultrafiltration, the amount of organic matter was reduced by approximately 70%, whereas aromaticity increased in all fractions, indicating preferential elimination of aliphatic wastewater compounds. Most of the remaining fractions at the end of the process consisted of a yellow residue rich in low molecular weight AS fractions.

  5. Monitoring extent of moisture variations due to leachate recirculation in an ELR/bioreactor landfill using resistivity imaging.

    PubMed

    Manzur, Shahed Rezwan; Hossain, Md Sahadat; Kemler, Vance; Khan, Mohammad Sadik

    2016-09-01

    Bioreactor or enhanced leachate recirculation (ELR) landfills are designed and operated for accelerated waste stabilization, accelerated decomposition, and an increased rate of gas generation. The major aspects of a bioreactor landfill are the addition of liquid and the recirculation of collected leachate back into the waste mass through the subsurface leachate recirculation system (LRS). The performance of the ELR landfill largely depends on the existing moisture content within the waste mass; therefore, it is of utmost importance to determine the moisture variations within the landfill. Traditionally, the moisture variation of the ELR landfill is determined by collecting samples through a bucket auger boring from the landfill, followed by laboratory investigation. Collecting the samples through a bucket auger boring is time consuming, labor intensive, and cost prohibitive. Moreover, it provides the information for a single point within the waste mass, but not for the moisture distribution within the landfill. Fortunately, 2D resistivity imaging (RI) can be performed to assess the moisture variations within the landfill and provide a continuous image of the subsurface, which can be utilized to evaluate the performance of the ELR landfill. During this study, the 2D resistivity imaging technique was utilized to determine the moisture distribution and moisture movement during the recirculation process of an ELR landfill in Denton, Texas, USA. A horizontal recirculation pipe was selected and monitored periodically for 2.5years, using the RI technique, to investigate the performance of the leachate recirculation. The RI profile indicated that the resistivity of the solid waste decreased as much as 80% with the addition of water/leachate through the recirculation pipe. In addition, the recirculated leachate traveled laterally between 11m and 16m. Based on the resistivity results, it was also observed that the leachate flow throughout the pipe was non-uniform. The non

  6. Sequential anaerobic and aerobic treatment of pulp and paper mill effluent in pilot scale bioreactor.

    PubMed

    Singh, Pratibha

    2007-01-01

    In the present study sequential anaerobic and aerobic treatment in two step bioreactor was performed for removal of colour in the pulp and paper mill effluent. In anaerobic treatment, colour 50%, lignin 62%, COD 29%, absordable organic halides (AOX) 25% and phenol 29% were reduced in eight days. The anaerobically treated effluent was separately applied in bioreactor in presence of fungal strain, Paecilomyces sp., and bacterial strain, Microbrevis luteum. Data of study indicated reduction in colour 80%, AOX 74%, lignin 81%, COD 93% and phenol 76 per cent by Paecilomyces sp. where as Microbrevis luteum showed removal in colour 59%, lignin 71%, COD 86%, AOX 84% and phenol 88% by day third when 7 days anaerobically treated effluent was further treated by aerobic microorganisms. Change in pH of the effluent and increase in biomass of microorganism's substantiated results of the study, which was concomitant to the treatment method.

  7. Influence of aeration modes on leachate characteristic of landfills that adopt the aerobic-anaerobic landfill method.

    PubMed

    Wu, Chuanfu; Shimaoka, Takayuki; Nakayama, Hirofumi; Komiya, Teppei; Chai, Xiaoli; Hao, Yongxia

    2014-01-01

    As far as the optimal design, operation, and field application of the Aerobic-Anaerobic Landfill Method (AALM) are concerned, it is very important to understand how aeration modes (different combinations of aeration depth and air injection rate) affect the biodegradation of organic carbon and the transformation of nitrogen in landfill solid waste. Pilot-scale lysimeter experiments were carried out under different aeration modes to obtain detailed information regarding the influence of aeration modes on leachate characteristics. Results from these lysimeter experiments revealed that aeration at the bottom layer was the most effective for decomposition of organic carbon when compared with aeration at the surface or middle layers. Moreover, the air injection rate led to different nitrogen transformation patterns, unlike the lesser influence it has on organic carbon decomposition. Effective simultaneous nitrification and denitrification were observed for the aeration mode with a higher air injection rate (=1.0 L/min). On the other hand, the phenomenon of sequenced nitrification and denitrification could be observed when a low air injection rate (=0.5L/min.) was employed. Finally, it is concluded that, for AALM, air injection with a higher air injection rate at the deepest layer near the leachate collection pipe tends to accelerate the stabilization of landfill waste as defined in terms of the enhancement of denitrification as well as organic carbon decomposition.

  8. Hydrogen sulfide (H2S) emission control by aerobic sulfate reduction in landfill

    NASA Astrophysics Data System (ADS)

    Long, Yuyang; Fang, Yuan; Shen, Dongsheng; Feng, Huajun; Chen, Ting

    2016-12-01

    H2S emissions from landfill sites resulting from sulfate reduction has become a serious human health and ecological safety issue. This study investigated H2S emission behavior and sulfate metabolism occurring in simulated landfills under different operating conditions. Under aerobic conditions, great attenuation of the original sulfate content (from around 6000 mg kg‑1 dropped to below 800 mg kg‑1) with corresponding accumulation of sulfides and elemental sulfur were observed, indicating that sulfate reduction processes were intense under such conditions. Analysis of the bacterial community in these landfills showed great abundance (1.10%) and diversity of sulfur reducing types, confirming their active involvement in this process. In particular, the total abundance of sulfate-reducing bacteria increased nearly 30 times under aerobic conditions, leading to the transformation of sulfate to sulfide and other reduced sulfur species. Although exposure to air promoted the accumulation of sulfide, it did not lead to an increase in H2S release in these landfills.

  9. Hydrogen sulfide (H2S) emission control by aerobic sulfate reduction in landfill

    PubMed Central

    Long, Yuyang; Fang, Yuan; Shen, Dongsheng; Feng, Huajun; Chen, Ting

    2016-01-01

    H2S emissions from landfill sites resulting from sulfate reduction has become a serious human health and ecological safety issue. This study investigated H2S emission behavior and sulfate metabolism occurring in simulated landfills under different operating conditions. Under aerobic conditions, great attenuation of the original sulfate content (from around 6000 mg kg−1 dropped to below 800 mg kg−1) with corresponding accumulation of sulfides and elemental sulfur were observed, indicating that sulfate reduction processes were intense under such conditions. Analysis of the bacterial community in these landfills showed great abundance (1.10%) and diversity of sulfur reducing types, confirming their active involvement in this process. In particular, the total abundance of sulfate-reducing bacteria increased nearly 30 times under aerobic conditions, leading to the transformation of sulfate to sulfide and other reduced sulfur species. Although exposure to air promoted the accumulation of sulfide, it did not lead to an increase in H2S release in these landfills. PMID:27909309

  10. Removal of N-nitrosamines by an aerobic membrane bioreactor.

    PubMed

    Wijekoon, Kaushalya C; Fujioka, Takahiro; McDonald, James A; Khan, Stuart J; Hai, Faisal I; Price, William E; Nghiem, Long D

    2013-08-01

    This study investigated the fate of eight N-nitrosamines during membrane bioreactor (MBR) treatment. The results suggest that biodegradation is mainly responsible for the removal of N-nitrosamines during MBR treatment. Other removal mechanisms were insignificant (e.g. adsorption to sludge) or not expected (e.g. photolysis and volatilization) given the experimental conditions and physicochemical properties of the N-nitrosamines studied here. N-nitrosamine removal efficiencies were from 24% to 94%, depending on their molecular properties. High removal of N-nitrosamines such as N-nitrosodimethylamine and N-nitrosodiethylamine could be explained by the presence of strong electron donating functional groups (EDG) in their structure. In contrast, N-nitrosomorpholine possessing the weak EDG morpholine was persistent to biodegradation. The removal efficiency of N-nitrosomorpholine was 24% and was the lowest amongst all N-nitrosamines investigated in this study.

  11. Release of non-methane organic compounds during simulated landfilling of aerobically pretreated municipal solid waste.

    PubMed

    Zhang, Yuanyuan; Yue, Dongbei; Liu, Jianguo; Lu, Peng; Wang, Ying; Liu, Jing; Nie, Yongfeng

    2012-06-30

    Characteristics of non-methane organic compounds (NMOCs) emissions during the anaerobic decomposition of untreated (APD-0) and four aerobically pretreated (APD-20, APD-39, APD-49, and APD-63) samples of municipal solid waste (MSW) were investigated in laboratory. The cumulative mass of the NMOCs of APD-20, APD-39, APD-49, and APD-63 accounted for 15%, 9%, 16%, and 15% of that of APD-0, respectively. The intensities of the NMOC emissions calculated by dividing the cumulative NMOC emissions by the quantities of organic matter removed (Q(VS)) decreased from 4.1 mg/kg Q(VS) for APD-0 to 0.8-3.4 mg/kg Q(VS) for aerobically pretreated MSW. The lipid and starch contents might have significant impact on the intensity of the NMOC emissions. Alkanes dominated the NMOCs released from the aerobically pretreated MSW, while oxygenated compounds were the chief component of the NMOCs generated from untreated MSW. Aerobic pretreatment of MSW prior to landfilling reduces the organic content of the waste and the intensity of the NMOC emissions, and increases the odor threshold, thereby reducing the environmental impact of landfills.

  12. Stable aerobic granules in continuous-flow bioreactor with self-forming dynamic membrane.

    PubMed

    Liu, Hongbo; Li, Yajie; Yang, Changzhu; Pu, Wenhong; He, Liu; Bo, Fu

    2012-10-01

    A novel continuous-flow bioreactor with aerobic granular sludge and self-forming dynamic membrane (CGSFDMBR) was developed for efficient wastewater treatment. Under continuous-flow operation, aerobic granular sludge was successfully cultivated and characterized with small particle size of about 0.1-1.0mm, low settling velocity of about 15-25 m/h, loose structure and high water content of about 96-98%. To maintain the stability of aerobic granular sludge, strategies based on the differences of settling velocity and particle-size between granular and flocculent sludge were implemented. Moreover, in CGSFDMBR, membrane fouling was greatly relieved. Dynamic membrane was just cleaned once in more than 45 days' operation. CGSFDMBR presented good performance in treating septic tank wastewater, obtaining average COD, NH(4)(+)-N, TN and TP removal rates of 83.3%, 73.3%, 67.3% and 60%, respectively, which was more efficient than conventional bioreactors since that carbon, nitrogen and phosphorus were simultaneously removed in a single aerobic reactor.

  13. Kinetics of phenolic and phthalic acid esters biodegradation in membrane bioreactor (MBR) treating municipal landfill leachate.

    PubMed

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

    2016-05-01

    The kinetic of phenolic and phthalic acid esters (PAEs) biodegradation in membrane bioreactor (MBR) treating municipal landfill leachate was investigated. Laboratory-scale MBR was fed with mixture of fresh and stabilized landfill leachate containing carbon to nitrogen (C/N) ratio of 10, 6, 3 and operated under different solid retention time (SRT) of 90, 15 and 5 d. Batch experiments using MBR sludge obtained from each steady-state operating condition revealed highest biodegradation rate constant (k) of 0.059-0.092 h(-1) of the phenolic and PAEs compounds at C/N of 6. Heterotrophic bacteria were the major group responsible for biodegradation of compounds whereas the presence of ammonia-oxidizing bacteria (AOB) helped accelerating their removals. Heterotrophic nitrifying bacteria found under high ammonia condition had an important role in enhancing the biodegradation of phenols and PAEs by releasing phenol hydroxylase (PH), esterase (EST) and phthalate dioxygenase (PDO) enzymes and the presence of AOB helped improving biodegradation of phenolic and PAEs compounds through their co-metabolism.

  14. Liquid balance monitoring inside conventional, Retrofit, and bio-reactor landfill cells

    SciTech Connect

    Abichou, Tarek; Barlaz, Morton A.; Green, Roger; Hater, Gary

    2013-10-15

    Highlights: • The Retrofit, Control, and As-Built cells received 48, 14, and 213 L Mg{sup −1} (liters of liquids per metric ton of waste). • The leachate collection system yielded 60, 57 and 198 L Mg{sup −1} from the Retrofit, Control, and As-Built cells. • The head on liner in all cells was below regulatory limits. • Measured moisture content of the waste samples was consistent with that calculated from accumulated liquid by balance. • The in-place saturated hydraulic conductivity of the MSW was calculated to be in the range of 10{sup −8} to 10{sup −7} m s{sup −1}. - Abstract: The Outer Loop landfill bioreactor (OLLB) in Louisville, KY, USA has been the site of a study to evaluate long-term bioreactor performance at a full-scale operational landfill. Three types of landfill units were studied including a conventional landfill (Control cell), a new landfill area that had an air addition and recirculation piping network installed as waste was being placed (As-Built cell), and a conventional landfill that was modified to allow for liquids recirculation (Retrofit cell). During the monitoring period, the Retrofit, Control, and As-Built cells received 48, 14, and 213 L Mg{sup −1} (liters of liquids per metric ton of waste), respectively. The leachate collection system yielded 60, 57 and 198 L Mg{sup −1} from the Retrofit, Control, and As-Built cells, respectively. The head on liner in all cells was below regulatory limits. In the Control and As-Built cells, leachate head on liner decreased once waste placement stopped. The measured moisture content of the waste samples was consistent with that calculated from the estimate of accumulated liquid by the liquid balance. Additionally, measurements on excavated solid waste samples revealed large spatial variability in waste moisture content. The degree of saturation in the Control cells decreased from 85% to 75%. The degree of saturation increased from 82% to 83% due to liquids addition in the Retrofit

  15. Influence of dynamic coupled hydro-bio-mechanical processes on response of municipal solid waste and liner system in bioreactor landfills.

    PubMed

    Reddy, Krishna R; Kumar, Girish; Giri, Rajiv K

    2017-01-03

    A two-dimensional (2-D) mathematical model is presented to predict the response of municipal solid waste (MSW) of conventional as well as bioreactor landfills undergoing coupled hydro-bio-mechanical processes. The newly developed and validated 2-D coupled mathematical modeling framework combines and simultaneously solves a two-phase flow model based on the unsaturated Richard's equation, a plain-strain formulation of Mohr-Coulomb mechanical model and first-order decay kinetics biodegradation model. The performance of both conventional and bioreactor landfill was investigated holistically, by evaluating the mechanical settlement, extent of waste degradation with subsequent changes in geotechnical properties, landfill slope stability, and in-plane shear behavior (shear stress-displacement) of composite liner system and final cover system. It is concluded that for the given specific conditions considered, bioreactor landfill attained an overall stabilization after a continuous leachate injection of 16years, whereas the stabilization was observed after around 50years of post-closure in conventional landfills, with a total vertical strain of 36% and 37% for bioreactor and conventional landfills, respectively. The significant changes in landfill settlement, the extent of MSW degradation, MSW geotechnical properties, along with their influence on the in-plane shear response of composite liner and final cover system, between the conventional and bioreactor landfills, observed using the mathematical model proposed in this study, corroborates the importance of considering coupled hydro-bio-mechanical processes while designing and predicting the performance of engineered bioreactor landfills. The study underscores the importance of considering the effect of coupled processes while examining the stability and integrity of the liner and cover systems, which form the integral components of a landfill. Moreover, the spatial and temporal variations in the landfill settlement, the

  16. Effects of Bioreactor Retention Time on Aerobic Microbial Decomposition of CELSS Crop Residues

    NASA Technical Reports Server (NTRS)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.

    1997-01-01

    The focus of resource recovery research at the KSC-CELSS Breadboard Project has been the evaluation of microbiologically mediated biodegradation of crop residues by manipulation of bioreactor process and environmental variables. We will present results from over 3 years of studies that used laboratory- and breadboard-scale (8 and 120 L working volumes, respectively) aerobic, fed-batch, continuous stirred tank reactors (CSTR) for recovery of carbon and minerals from breadboard grown wheat and white potato residues. The paper will focus on the effects of a key process variable, bioreactor retention time, on response variables indicative of bioreactor performance. The goal is to determine the shortest retention time that is feasible for processing CELSS crop residues, thereby reducing bioreactor volume and weight requirements. Pushing the lower limits of bioreactor retention times will provide useful data for engineers who need to compare biological and physicochemical components. Bioreactor retention times were manipulated to range between 0.25 and 48 days. Results indicate that increases in retention time lead to a 4-fold increase in crop residue biodegradation, as measured by both dry weight losses and CO2 production. A similar overall trend was also observed for crop residue fiber (cellulose and hemicellulose), with a noticeable jump in cellulose degradation between the 5.3 day and 10.7 day retention times. Water-soluble organic compounds (measured as soluble TOC) were appreciably reduced by more than 4-fold at all retention times tested. Results from a study of even shorter retention times (down to 0.25 days), in progress, will also be presented.

  17. Effects of bioreactor retention time on aerobic microbial decomposition of CELSS crop residues

    NASA Astrophysics Data System (ADS)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.

    1997-01-01

    The focus of resource recovery research at the KSC-CELSS Breadboard Project has been the evaluation of microbiologically mediated biodegradation of crop residues by manipulation of bioreactor process and environmental variables. We will present results from over 3 years of studies that used laboratory- and breadboard-scale (8 and 120 L working volumes, respectively) aerobic, fed-batch, continuous stirred tank reactors (CSTR) for recovery of carbon and minerals from breadboard grown wheat and white potato residues. The paper will focus on the effects of a key process variable--bioreactor retention time--on response variables indicative of bioreactor performance. The goal is to determine the shortest retention time that is feasible for processing CELSS crop residues, thereby reducing bioreactor volume and weight requirements. Pushing the lower limits of bioreactor retention times will provide useful data for engineers who need to compare biological and physicochemical components. Bioreactor retention times were manipulated to range between 0.25 and 48 days. Results indicate that increases in retention time lead to a 4-fold increase in crop residue biodegradation, as measured by both dry weight losses and CO_2 production. A similar overall trend was also observed for crop residue fiber (cellulose and hemicellulose), with a noticeable jump in cellulose degradation between the 5.3 day and 10.7 day retention times. Water-soluble organic compounds (measured as soluble TOC) were appreciably reduced by more than 4-fold at all retention times tested. Results from a study of even shorter retention times (down to 0.25 days), in progress, will also be presented.

  18. Development of an Intermediate-Scale Aerobic Bioreactor to Regenerate Nutrients from Inedible Crop Residues

    NASA Technical Reports Server (NTRS)

    Finger, Barry W.; Strayer, Richard F.

    1994-01-01

    Three Intermediate-Scale Aerobic Bioreactors were designed, fabricated, and operated. They utilized mixed microbial communities to bio-degrade plant residues. The continuously stirred tank reactors operated at a working volume of 8 L, and the average oxygen mass transfer coefficient, k(sub L)a, was 0.01 s(exp -1). Mixing time was 35 s. An experiment using inedible wheat residues, a replenishment rate of 0.125/day, and a solids loading rate of 20 gdw/day yielded a 48% reduction in biomass. Bioreactor effluent was successfully used to regenerate a wheat hydroponic nutrient solution. Over 80% of available potassium, calcium, and other minerals were recovered and recycled in the 76-day wheat growth experiment.

  19. [Variation characteristics of leachate quality in a semi-aerobic municipal solid waste landfill].

    PubMed

    Yang, Yufei; Huang, Qifei; Wang, Qi; Liu, Yuqiang; Dong, Lu

    2005-11-01

    A large-scale semi-aerobic landfill set (21 m x 3.8 m x 6.0 m) was constructed to study the variation characteristics of pollutants in the landfill leachate. The results showed that after 39 weeks, the concentrations of CODCr, BOD5 and NH3+-N in the leachate declined rapidly, which reached 173, 30 and 15 mg x L(-1) respectively, and the reducing rate of NH3+-N was 99.6%. The pH value was below 7 during the first 2 weeks, but became weak alkaline after three weeks. Based on the experimental data, the attenuation equations of pollutants in the leachate were built.

  20. Landfills

    EPA Pesticide Factsheets

    To provide information on landfills, including laws/regulations, and technical guidance on municipal solid waste, hazardous waste, industrial, PCBs, and construction and debris landfills. To provide resources for owners and operators of landfills.

  1. Organic micropollutants in aerobic and anaerobic membrane bioreactors: Changes in microbial communities and gene expression.

    PubMed

    Harb, Moustapha; Wei, Chun-Hai; Wang, Nan; Amy, Gary; Hong, Pei-Ying

    2016-10-01

    Organic micro-pollutants (OMPs) are contaminants of emerging concern in wastewater treatment due to the risk of their proliferation into the environment, but their impact on the biological treatment process is not well understood. The purpose of this study is to examine the effects of the presence of OMPs on the core microbial populations of wastewater treatment. Two nanofiltration-coupled membrane bioreactors (aerobic and anaerobic) were subjected to the same operating conditions while treating synthetic municipal wastewater spiked with OMPs. Microbial community dynamics, gene expression levels, and antibiotic resistance genes were analyzed using molecular-based approaches. Results showed that presence of OMPs in the wastewater feed had a clear effect on keystone bacterial populations in both the aerobic and anaerobic sludge while also significantly impacting biodegradation-associated gene expression levels. Finally, multiple antibiotic-type OMPs were found to have higher removal rates in the anaerobic MBR, while associated antibiotic resistance genes were lower.

  2. Onsite survey on the mechanism of passive aeration and air flow path in a semi-aerobic landfill.

    PubMed

    Matsuto, Toshihiko; Zhang, Xin; Matsuo, Takayuki; Yamada, Shuhei

    2015-02-01

    The semi-aerobic landfill is a widely accepted landfill concept in Japan because it promotes stabilization of leachates and waste via passive aeration without using any type of mechanical equipment. Ambient air is thought to be supplied to the landfill through a perforated pipe network made of leachate collection pipe laid along the bottom and a vertically erected gas vent. However, its underlying air flow path and driving forces are unclear because empirical data from real-world landfills is inadequate. The objective of this study is to establish scientific evidence about the aeration mechanisms and air flow path by an on-site survey of a full-scale, semi-aerobic landfill. First, all passive vents located in the landfill were monitored with respect to temperature level and gas velocity in different seasons. We found a linear correlation between the outflow rate and gas temperature, suggesting that air flow is driven by a buoyancy force caused by the temperature difference between waste in the landfill and the ambient temperature. Some vents located near the landfill bottom acted as air inflow vents. Second, we conducted a tracer test to determine the air flow path between two vents, by injecting tracer gas from an air sucking vent. The resulting slowly increasing gas concentration at the neighboring vent suggested that fresh air flow passes through the waste layer toward the gas vents from leachate collection pipes, as well as directly flowing through the pipe network. Third, we monitored the temperature of gas flowing out of a vent at night. Since the temperature drop of the gas was much smaller than that of the environment, the air collected at the gas vents was estimated to flow mostly through the waste layer, i.e., the semi-aerobic landfill has considerable aeration ability under the appropriate conditions.

  3. Enhanced biodegradation of phenolic compounds in landfill leachate by enriched nitrifying membrane bioreactor sludge.

    PubMed

    Boonyaroj, Varinthorn; Chiemchaisri, Chart; Chiemchaisri, Wilai; Yamamoto, Kazuo

    2017-02-05

    The role of autotrophic nitrification on the biodegradation of toxic organic micro-pollutants presented in landfill leachate was assessed. A two-stage MBR system consisting of an inclined tube incorporated anoxic reactor followed by aerobic submerged membrane reactor was operated under long sludge age condition in which nitrifying bacteria could be enriched. During the reactor operation, organic removal efficiencies were more than 90% whereas phenolic compounds including bisphenol A (BPA) and 4-methyl-2,6-di-tert-butylphenol (BHT) were removed by 65 and 70% mainly through biodegradation in the aerobic reactor even at high feed concentrations of 1000μg/L for both compounds. Batch experiments revealed that enriched nitrifying sludge with nitrifying activities could biodegraded 88 and 75% of BPA and BHT, largely improved from non-nitrifying sludge and enriched nitrifying sludge with the presence of inhibitor. The first-order kinetic rates of BHT and BPA removal were 0.0108 and 0.096h(-1), also enhanced by 44% from the non-nitrifying sludge.

  4. Recirculation of reverse osmosis concentrate in lab-scale anaerobic and aerobic landfill simulation reactors.

    PubMed

    Morello, Luca; Cossu, Raffaello; Raga, Roberto; Pivato, Alberto; Lavagnolo, Maria Cristina

    2016-10-01

    Leachate treatment is a major issue in the context of landfill management, particularly in view of the consistent changes manifested over time in the quality and quantity of leachate produced, linked to both waste and landfill characteristics, which renders the procedure technically difficult and expensive. Leachate recirculation may afford a series of potential advantages, including improvement of leachate quality, enhancement of gas production, acceleration of biochemical processes, control of moisture content, as well as nutrients and microbe migration within the landfill. Recirculation of the products of leachate treatment, such as reverse osmosis (RO) concentrate, is a less common practice, with widespread controversy relating to its suitability, potential impacts on landfill management and future gaseous and leachable emissions. Scientific literature provides the results of only a few full-scale applications of concentrate recirculation. In some cases, an increase of COD and ammonium nitrogen in leachate was observed, coupled with an increase of salinity; which, additionally, might negatively affect performance of the RO plant itself. In other cases, not only did leachate production not increase significantly but the characteristics of leachate extracted from the well closest to the re-injection point also remained unchanged. This paper presents the results of lab-scale tests conducted in landfill simulation reactors, in which the effects of injection of municipal solid waste (MSW) landfill leachate RO concentrate were evaluated. Six reactors were managed with different weekly concentrate inputs, under both anaerobic and aerobic conditions, with the aim of investigating the short and long-term effects of this practice on landfill emissions. Lab-scale tests resulted in a more reliable identification of compound accumulation and kinetic changes than full-scale applications, further enhancing the development of a mass balance in which gaseous emissions and waste

  5. Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell

    SciTech Connect

    Tallec, G.; Bureau, C.; Peu, P.; Benoist, J.C.; Lemunier, M.; Budka, A.; Presse, D.; Bouchez, T.

    2009-07-15

    This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N{sub 2}O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO{sub 2}, CH{sub 4} and N{sub 2}O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N{sub 2}O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N{sub 2}O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N{sub 2}O releases: 8.1 {+-} 0.16 mg m{sup -2} d{sup -1} (n = 384), 4.2 {+-} 0.14 mg m{sup -2} d{sup -1} (n = 132) and 1.9 {+-} 0.10 mg m{sup -2} d{sup -1} (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N{sub 2}O gaseous surface releases and recirculation events were evidenced. Estimated N{sub 2}O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection.

  6. Micropollutants removal in an anaerobic membrane bioreactor and in an aerobic conventional treatment plant.

    PubMed

    Abargues, M R; Robles, A; Bouzas, A; Seco, A

    2012-01-01

    The paper expresses an attempt to tackle the problem due to the presence of micropollutants in wastewater which may be able to disrupt the endocrine system of some organisms. These kinds of compounds are ubiquitously present in municipal wastewater treatment plant (WWTP) effluents. The aim of this paper is to compare the fate of the alkylphenols-APs (4-(tert-octyl)) phenol, t-nonylphenol and 4-p-nonylphenol and the hormones (estrone, 17β-estradiol and 17α-ethinylestradiol) in a submerged anaerobic membrane bioreactor (SAMBR) pilot plant and in a conventional activated sludge wastewater treatment plant (CTP). The obtained results are also compared with the results obtained in a previous study carried out in an aerobic MBR pilot plant. The results showed that the APs soluble concentrations in the SAMBR effluent were always significantly higher than the CTP ones. Moreover, the analyses of the suspended fraction revealed that the AP concentrations in the SAMBR reactor were usually higher than in the CTP reactor, indicating that under anaerobic conditions the APs were accumulated in the digested sludge. The aerobic conditions maintained both in the CTP system and in the aerobic MBR favoured the APs and hormones degradation, and gave rise to lower concentrations in the effluent and in the reactor of these systems. Furthermore, the results also indicated that the degradation of APs under aerobic conditions was enhanced working at high solid retention time (SRT) and hydraulic retention time (HRT) values.

  7. Organic and nitrogen removal from landfill leachate in aerobic granular sludge sequencing batch reactors

    SciTech Connect

    Wei Yanjie; Ji Min; Li Ruying; Qin Feifei

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Aerobic granular sludge SBR was used to treat real landfill leachate. Black-Right-Pointing-Pointer COD removal was analyzed kinetically using a modified model. Black-Right-Pointing-Pointer Characteristics of nitrogen removal at different ammonium inputs were explored. Black-Right-Pointing-Pointer DO variations were consistent with the GSBR performances at low ammonium inputs. - Abstract: Granule sequencing batch reactors (GSBR) were established for landfill leachate treatment, and the COD removal was analyzed kinetically using a modified model. Results showed that COD removal rate decreased as influent ammonium concentration increasing. Characteristics of nitrogen removal at different influent ammonium levels were also studied. When the ammonium concentration in the landfill leachate was 366 mg L{sup -1}, the dominant nitrogen removal process in the GSBR was simultaneous nitrification and denitrification (SND). Under the ammonium concentration of 788 mg L{sup -1}, nitrite accumulation occurred and the accumulated nitrite was reduced to nitrogen gas by the shortcut denitrification process. When the influent ammonium increased to a higher level of 1105 mg L{sup -1}, accumulation of nitrite and nitrate lasted in the whole cycle, and the removal efficiencies of total nitrogen and ammonium decreased to only 35.0% and 39.3%, respectively. Results also showed that DO was a useful process controlling parameter for the organics and nitrogen removal at low ammonium input.

  8. Characterization and treatment of Denizli landfill leachate using anaerobic hybrid/aerobic CSTR systems.

    PubMed

    Ağdağ, Osman Nuri

    2011-01-01

    Leachate generated in municipal solid waste landfill contains large amounts of organic and inorganic contaminants. In the scope of the study, characterization and anaerobic/aerobic treatability of leachate from Denizli (Turkey) Sanitary Landfill were investigated. Time-based fluctuations in characteristics of leachate were monitored during a one-year period. In characterization study; chemical oxygen demand (COD), biochemical oxygen demand (BOD) dissolved oxygen, temperature, pH, alkalinity, volatile fatty acids, total nitrogen, NH4-N, BOD5/COD ratio, suspended solid, inert COD, anaerobic toxicity assay and heavy metals concentrations in leachate were monitored. Average COD, BOD and NH4-N concentration in leachate were measured as 18034 mg/l, 11504 mg/l and 454 mg/l, respectively. Generally, pollution parameters in leachate were higher in summer and relatively lower in winter due to dilution by precipitation. For treatment of leachate, two different reactors, namely anaerobic hybrid and aerobic completely stirred tank reactor (CSTR) having effective volumes of 17.7 and 10.5 litres, respectively, were used. After 41 days of start-up period, leachate was loaded to hybrid reactor at 10 different organic loading rates (OLRs). OLR was increased by increasing COD concentrations. COD removal efficiency of hybrid reactor was carried out at a maximum of 91%. A percentage of 96% of residual COD was removed in the aerobic reactor. NH4-N removal rate in CSTR was quite high. In addition, high methane content was obtained as 64% in the hybrid reactor. At the end of the study, after 170 operation days, it can be said that the hybrid reactor and CSTR were very effective for leachate treatment.

  9. Effects of oxygen and carbon content on nitrogen removal capacities in landfill bioreactors and response of microbial dynamics.

    PubMed

    Xu, Weiqing; Wu, Dong; Wang, Jie; Huang, Xinghua; Xie, Bing

    2016-07-01

    In this study, landfill bioreactors were tested to treat the recalcitrant leachate-nitrogen and the impacts of relevant operational parameters on its conversion were comprehensively investigated. We found that the highly diverse microbial community in landfill bioreactors could be substantially affected by increasing biodegradable carbon and oxygen content, which led to the whole system's intrinsic nitrogen removal capacity increasing from 50 to 70 %, and meanwhile, the contribution of anammox was detected less than 20 %. The sequencing and q-PCR results showed that microbial community in bioreactor was dominated by Proteobacteria (∼35 %) and Acidobacteria (~20 %) during the whole experiment. The abundance of anammox functioning bacteria (Amx) kept at a stable level (-2.5 to -2.2 log (copies/16S rRNA)) and was not statistically correlated to the abundance of anammox bacteria. However, significant linear correlation (p < 0.05) was determined between the abundance of nirS and Proteobacteria; amoA and AOB. Redundancy analysis (RDA) suggested that although oxygen and biodegradable carbon can both impose effects on microbial community structure, only biodegradable carbon content is the determinant in the total nitrogen removal.

  10. Co-digestion of mixed industrial sludge with municipal solid wastes in anaerobic simulated landfilling bioreactors.

    PubMed

    Ağdağ, Osman Nuri; Sponza, Delia Teresa

    2007-02-09

    In this study, the feasibility of the anaerobic co-digestion of a mixed industrial sludge with municipal solid wastes (MSW) was investigated in three simulated anaerobic landfilling bioreactors during a 150-day period. All of the reactors were operated with leachate recirculation. One of them was loaded only with MSW (control reactor); the second reactor was loaded with mixed industrial sludge and MSW, the weight ratio of the MSW to mixed industrial sludge was 1:1 (based on dry solid) (Run 1); the third reactor was loaded with mixed industrial sludge and MSW, the weight ratio of the MSW to mixed industrial sludge was 1:2 (based on dry solid) (Run 2). The VFA concentrations decreased significantly in Run 1 and Run 2 reactors at the end of 150 days. The pH values were higher in Run 1 and Run 2 reactors compared to control reactor. The differences between leachate characteristics, the biodegradation and the bioefficiency of the reactors were compared. The NH(4)-N concentrations released to leachate from mixed sludge in Run 1 and Run 2 reactors were lower than that of control reactor. The BOD(5)/COD ratios in Run 1 and Run 2 reactors were lower than that of control reactor at the end of 150 days. Cumulative methane gas productions and methane percentages were higher in Run 1 and Run 2 reactors. Reductions in waste quantity, carbon percentage and settlement of the waste were better in Run 1 and Run 2 reactors compared to control reactor at the end of 150 days. Furthermore, TN and TP removals in waste were higher in reactors containing industrial sludge compared to control. The toxicity test results showed that toxicity was observed in reactors containing industrial mixed sludge.

  11. Comparative analysis of mixing distribution in aerobic stirred bioreactor for simulated yeasts and fungus broths.

    PubMed

    Cascaval, Dan; Galaction, Anca-Irina; Turnea, Marius

    2007-01-01

    The study on mixing distribution for an aerobic stirred bioreactor and simulated (solutions of carboxymethylcellulose sodium salt), yeasts (S. cerevisiae) and fungus (P. chrysogenum pellets and free mycelia) broths indicated the significant variation of mixing time on the bioreactor height. The experiments suggested the possibility to reach a uniform mixing in whole bulk of the real broths for a certain value of rotation speed or biomass concentration domain. For S. cerevisiae broths the optimum rotation speed increased to 500 rpm with the biomass accumulation from 40 to 150 g/l d.w. Irrespective of their morphology, for fungus cultures the existence of optimum rotation speed (500 rpm) has been recorded only for biomass concentration below 24 g/l d.w. The influence of aeration rate depends on the apparent viscosity/biomass concentration and on the impellers and sparger positions. By increasing the apparent viscosity for simulated broths, or biomass amount for real broths, the shape of the curves describing the mixing time variation is significantly changed for all the considered positions. The intensification of the aeration induced the increase of mixing time, which reached a maximum value, decreasing then, due to the flooding phenomena. This variation became more pronounced at higher viscosities for simulated broths, at higher yeasts concentration, and at lower pellets or filamentous fungus concentration, respectively. By means of the experimental data and using MATLAB software, some mathematical correlations for mixing time have been proposed for each broth and considered position inside the bioreactor. These equations offer a good agreement with the experiment, the maximum deviation being +/-7.3% for S. cerevisiae broths.

  12. Particulate organics degradation and sludge minimization in aerobic, complete SRT bioreactors.

    PubMed

    Amanatidou, Elisavet; Samiotis, Georgios; Trikoilidou, Eleni; Tsikritzis, Lazaros

    2016-05-01

    The study evaluates the assumption that in activated sludge processes and under specific operating conditions, the considered unbiodegradable particulate organic fractions of influent (XU) organic solids and biomass decay residues (cell debris, XE) are degraded. The evaluation was performed by comparing sludge observed yield (Yobs) evolution in two full scale, complete solids retention time (SRT), aerobic bioreactors, to the predictions of two activated sludge models. The results showed that in steady state operating conditions of complete solids retention AS processes very low solids accumulation occur. In these conditions, solids accumulation is slightly affected by kinetic coefficients and significantly affected by XU and XE degradation rates. High endogenous residues degradation rate values of 0.05 d(-1) and 0.02 d(-1) were estimated for the two bioreactors, resulting in low solids accumulation, calculated at 1.6 tons and 3.59 tons per year respectively, of which 1.37 and 0.87 tons were non volatile suspended solids. Depending on WWTP operating conditions the endogenous residues degradation rate is the limiting factor of solids accumulation and consequently for particulate organics degradation.

  13. Preparation of activated carbon from sugarcane bagasse by microwave assisted activation for the remediation of semi-aerobic landfill leachate.

    PubMed

    Foo, K Y; Lee, L K; Hameed, B H

    2013-04-01

    This study evaluates the sugarcane bagasse derived activated carbon (SBAC) prepared by microwave heating for the adsorptive removal of ammonical nitrogen and orthophosphate from the semi-aerobic landfill leachate. The physical and chemical properties of SBAC were examined by pore structural analysis, scanning electron microscopy, Fourier transform infrared spectroscopy and elemental analysis. The effects of adsorbent dosage, contact time and solution pH on the adsorption performance were investigated in a batch mode study at 30°C. Equilibrium data were favorably described by the Langmuir isotherm model, with a maximum monolayer adsorption capacity for ammonical nitrogen and orthophosphate of 138.46 and 12.81 mg/g, respectively, while the adsorption kinetic was best fitted to the pseudo-second-order kinetic model. The results illustrated the potential of sugarcane bagasse derived activated carbon for the adsorptive treatment of semi-aerobic landfill leachate.

  14. Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators

  15. Performance of aerobic granular sludge in a sequencing batch bioreactor exposed to ofloxacin, norfloxacin and ciprofloxacin.

    PubMed

    Amorim, Catarina L; Maia, Alexandra S; Mesquita, Raquel B R; Rangel, António O S S; van Loosdrecht, Mark C M; Tiritan, Maria Elizabeth; Castro, Paula M L

    2014-03-01

    A granular sludge sequencing batch reactor (SBR) was operated for 340 days for treating a synthetic wastewater containing fluoroquinolones (FQs), namely ofloxacin, norfloxacin and ciprofloxacin. The SBR was intermittently fed with FQs, at concentrations of 9 and 32 μM. No evidence of FQ biodegradation was observed but the pharmaceutical compounds adsorbed to the aerobic granular sludge, being gradually released into the medium in successive cycles after stopping the FQ feeding. Overall COD removal was not affected during the shock loadings. Activity of ammonia oxidizing bacteria and nitrite oxidizing bacteria did not seem to be inhibited by the presence of FQs (maximum of 0.03 and 0.01 mM for ammonium and nitrite in the effluent, respectively). However, during the FQs feeding, nitrate accumulation up to 1.7 mM was observed at the effluent suggesting that denitrification was inhibited. The activity of phosphate accumulating organisms was affected, as indicated by the decrease of P removal capacity during the aerobic phase. Exposure to the FQs also promoted disintegration of the granules leading to an increase of the effluent solid content, nevertheless the solid content at the bioreactor effluent returned to normal levels within ca. 1 month after removing the FQs in the feed allowing recovery of the bedvolume. Denaturing gradient gel electrophoresis revealed a dynamic bacterial community with gradual changes due to FQs exposure. Bacterial isolates retrieved from the granules predominantly belonged to α- and γ-branch of the Proteobacteria phylum. The capacity of the system to return to its initial conditions after withdrawal of the FQ compounds in the inlet stream, reinforced its robustness to deal with wastewaters containing organic pollutants.

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

    PubMed

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

    2014-08-01

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

  17. Stabilization of fine fraction from landfill mining in anaerobic and aerobic laboratory leach bed reactors.

    PubMed

    Mönkäre, Tiina J; Palmroth, Marja R T; Rintala, Jukka A

    2015-11-01

    Fine fraction (FF, <20 mm) from mined landfill was stabilized in four laboratory-scale leach bed reactors (LBR) over 180 days. The aim was to study feasibility of biotechnological methods to treat FF and if further stabilization of FF is possible. Four different stabilization methods were compared and their effects upon quality of FF were evaluated. Also during the stabilization experiment, leachate quality as well as gas composition and quantity were analyzed. The methods studied included three anaerobic LBRs (one without water addition, one with water addition, and one with leachate recirculation) and one aerobic LBR (with water addition). During the experiment, the most methane was produced in anaerobic LBR without water addition (18.0 L CH4/kg VS), while water addition and leachate recirculation depressed methane production slightly, to 16.1 and 16.4 L CH4/kg VS, respectively. Organic matter was also removed via the leachate and was measured as chemical oxygen demand (COD). Calculated removal of organic matter in gas and leachate was highest in LBR with water addition (59 g COD/kg VS), compared with LBR without water addition or with leachate recirculation (51 g COD/kg VS). Concentrations of COD, ammonium nitrogen and anions in leachate decreased during the experiment, indicating washout mechanism caused by water additions. Aeration increased sulfate and nitrate concentrations in leachate due to oxidized sulfide and ammonium. Molecular weight distributions of leachates showed that all the size categories decreased, especially low molecular weight compounds, which were reduced the most. Aerobic stabilization resulted in the lowest final VS/TS (13.1%), lowest respiration activity (0.9-1.2 mg O2/g TS), and lowest methane production after treatment (0.0-0.8 L CH4/kg VS), with 29% of VS being removed from FF. Anaerobic stabilization methods also reduced organic matter by 9-20% compared with the initial amount. Stabilization reduced the quantity of soluble nitrogen

  18. Treatment of paper mill effluent using an anaerobic/aerobic hybrid side-stream membrane bioreactor.

    PubMed

    Sheldon, M S; Zeelie, P J; Edwards, W

    2012-01-01

    This paper presents the design and operational performance data of an anaerobic/aerobic hybrid side-stream Membrane Bioreactor (MBR) process for treating paper mill effluent operated over a 6 month period. The paper mill effluent stream was characterized by a chemical oxygen demand (COD) range of between 1,600 and 4,400 mg/L and an average BOD of 2,400 mg/L. Despite large fluctuations in COD feed concentration, stable process performance was achieved. The anaerobic Expanded Granular Sludge Bed (EGSB) pre-treatment step effectively lowered the organic loading by 65 to 85%, thus lowering the MBR COD feed concentration to consistently below 750 mg/L. The overall MBR COD removal was consistent at an average of 96%, regardless of the effluent COD or changes in the hydraulic retention time (HRT) and organic loading rate (OLR). Combining a high-rate anaerobic pre-treatment EGSB with a Modified Ludzack-Ettinger (MLE) MBR process configuration produced a high quality permeate. Preliminary NF and RO results indicated an overall COD removal of around 97 and 98%, respectively.

  19. Protozoan indicators and extracellular polymeric substances alterations in an intermittently aerated membrane bioreactor treating mature landfill leachate.

    PubMed

    Remmas, Nikolaos; Melidis, Paraschos; Paschos, Georgios; Statiris, Evangelos; Ntougias, Spyridon

    2017-01-01

    A membrane bioreactor was operated under intermittent aeration and various organic loading rates (OLR: 0.070, 0.159 and 0.291 g COD L(-1) d(-1)) to remove carbon and nitrogen from mature landfill leachate, where external carbon source (glycerol) addition resulted in effective nitrate removal. A relative increase in soluble microbial product (SMP) over extracellular polymeric substances (EPS) was observed at the highest OLR and glycerol addition, whereas no membrane biofouling occurred. SMP (proteins and carbohydrates) and carbohydrate EPS correlated positively and negatively, respectively, with suspended solids and transmembrane pressure (TMP). Moreover, proteinous SMP significantly correlated with carbon and nitrogen load. Principal component analysis also revealed the influence of leachate organic and nitrogen content on biomass production, TMP and sessile ciliate densities. Although filamentous index (FI) was sustained at high levels (3-4), with Haliscomenobacter hydrossis being the main filamentous bacterium identified, no bulking phenomena occurred. High glycerol addition resulted in a rapid increase in sessile ciliate population. Increased Epistylis and Vorticella microstoma population was detected by microscopic examination during high glycerol addition, while a remarkable Rhogostoma population (supergroup Rhizaria) was identified by molecular techniques. The contribution of Rhizaria in nitrogen processes may lead to the dominance of Rhogostoma during landfill leachate treatment.

  20. Molecular weight distribution of a full-scale landfill leachate treatment by membrane bioreactor and nanofiltration membrane.

    PubMed

    Campagna, Marco; Cakmakcı, Mehmet; Yaman, F Büşra; Ozkaya, Bestamin

    2013-04-01

    In this study, Molecular weight (MW) distributions of a full-scale landfill leachate treatment plant consisting of membrane bioreactor (MBR) and nanofiltration (NF) membrane were investigated. The leachate was sampled from the equalization tank, and effluents of MBR and NF membrane in the landfill leachate treatment plant. Parameters of COD, TOC, TKN, NH4(+)-N and UV(254, 280 and 320) absorbance were analyzed to evaluate both the removal performance of the plant and MW distributions. MW distribution of samples were determined by ultrafiltration (UF) (100 kDa, 10 kDa, 5 kDa, 1 kDa and 500 Da) membranes. The results indicated that organic matter of one third percent is particulate or colloidal form and almost half of the organic fraction has a lower MW than 500 Da. In addition, organic matter had hydrophilic character. Most part of TKN was>500 Da with the corresponding rate of 92%. Further, UV absorbance of raw leachate (RW) decreased 85% after 500 Da.

  1. Permitting of Landfill Bioreactor Operations: Ten Years after the RD&D Rule

    EPA Science Inventory

    Prior to promulgation of the Rule, there were approximately 20 full-scale bioreactor projects in North America, including one in Canada. Of these, six were permitted by EPA (four Project XL sites and two projects listed separately under a cooperative research agreement at the Ou...

  2. Performance and kinetic evaluation of an integrated anaerobic-aerobic bioreactor in the treatment of palm oil mill effluent.

    PubMed

    Chan, Yi Jing; Chong, Mei Fong; Law, Chung Lim

    2017-04-01

    This work presents the evaluation of biokinetic coefficients for a novel integrated anaerobic-aerobic bioreactor (IAAB) at different organic loading rates (OLRs) (10.5-22.5 g COD/L per day) treating palm oil mill effluent. The overall efficiencies of the chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were more than 99% for OLR up to 19.5 g COD/L day with biogas production containing 48-64% of methane. The effluent quality remained stable (BOD < 80 mg/L) and satisfied with the discharge limit. Stover-Kincannon model was the most appropriate model to estimate the performance of anaerobic compartment of IAAB, while Monod model was best suited for describing the aerobic compartment.

  3. Sequential anaerobic-aerobic decolourization of a real textile wastewater in a two-phase partitioning bioreactor.

    PubMed

    Tomei, M Concetta; Mosca Angelucci, Domenica; Daugulis, Andrew J

    2016-12-15

    This work describes the application of a solid-liquid two-phase partitioning bioreactor (TPPB) for the removal of colour from a real textile wastewater containing reactive azo-dyes. Four polymers were tested over the pH range of 4-9 to select the most effective absorbant to be used as the partitioning phase in the TPPB. The best results were obtained with Hytrel 8206 at pH4 achieving ~70% colour removal, based on the dominant wavelength, in the first 5h of contact time, and 84% after 24h. Wastewater treatment was undertaken in a solid-liquid TPPB operated with Hytrel 8206 in sequential anaerobic-aerobic configuration. The reaction time of 23h was equally distributed between the anaerobic and aerobic phases and, to favour colour uptake, the pH was controlled at 4.5 in the first 4h of the anaerobic phase, and then increased to 7.5. Colour removal (for the dominant wavelength, 536nm) increased from 70 to 85% by modifying the bioreactor operation from single-phase to TPPB mode. Based on COD measurements nearly complete biodegradation of the intermediates produced in the anaerobic phase was obtained, both in the single-phase and two-phase mode, with better performance of the TPPB system reaching 75% CODDye removal.

  4. Antibiotic resistance of Escherichia coli in leachates from municipal solid waste landfills: comparison between semi-aerobic and anaerobic operations.

    PubMed

    Threedeach, Simanata; Chiemchaisri, Wilai; Watanabe, Toru; Chiemchaisri, Chart; Honda, Ryo; Yamamoto, Kazuo

    2012-06-01

    A bacterial susceptibility test to 31 antibiotics was conducted on the 80 isolated Escherichia coli from the leachates of the landfills in two different operations: semi-aerobic (SL) and anaerobic (AL) landfills. The average population of E. coli from SL and AL leachates were 2.2 × 10(4) and 9.4 × 10(3)CFU/100ml, respectively. Between 80.8% and 87.5% of the E. coli isolated from both leachates as resistant to the tested antibiotics and high resistances were found to doxycycline (53.8-68.8%), cephalothin (57.5-61.3%), tetracycline (51.3-67.5%) and minocycline (37.5-46.3%). The percentages of isolates resistant to most antibiotics were higher in the AL leachate. The exception was nitrofurantoin to which the isolates from the SL were highly resistant. E. coli from both sources showed similarly high susceptibilities (90-100%) to aminoglycosides, quinolones, chloramphenicol, sulfonamide and some new beta-lactams. The difference in available oxygen in landfills could affect E. coli susceptibility to antibiotics in leachates.

  5. Effect of organic fouling on micro-pollutant rejection in membrane bioreactor treating municipal solid waste landfill leachate.

    PubMed

    Sanguanpak, Samunya; Chiemchaisri, Chart; Chiemchaisri, Wilai; Yamamoto, Kazuo

    2015-01-01

    Effect of membrane fouling on the removal of micro-pollutants from municipal solid waste landfill leachate, i.e. 4-methyl-2,6-di-tert-butylphenol (BHT), bisphenol A (BPA), and bis(2-ethylhexyl)phthalate (DEHP), in membrane bioreactor (MBR) was investigated. Modifications of membrane surface properties were analyzed to determine their relationship with their removals. Membrane fouling was simulated with foulants of different particle sizes on cellulose acetate (CA) microfiltration membrane to investigate the effect of foulant characteristics on BHT, BPA, and DEHP retention in the filtration experiment. The rejection efficiencies of the organic micro-pollutants in the MBR were 82-97% by fouled membrane, and 70-90% by cleaned membrane. The fouled membrane provided higher rejection of micro-pollutants from about 5% for BPA and BHT to 19% for DEHP. These improvements were due to the modification of membrane surface characteristics in terms of surface morphology, and contact angle after membrane fouling. The degree of rejection was found to be dependent upon the characteristics of foulant deposited on CA membrane surface. Increasing foulant particle size and its density shifted the mechanism of micro-pollutant rejection from membrane pore narrowing to pore blocking and cake formation while increasing pollutant adsorption capacity onto the foulant layer.

  6. Removal of pharmaceuticals from synthetic wastewater in an aerobic granular sludge membrane bioreactor and determination of the bioreactor microbial diversity.

    PubMed

    Wang, Xiao-Chun; Shen, Ji-Min; Chen, Zhong-Lin; Zhao, Xia; Xu, Hao

    2016-09-01

    Five types of pharmaceuticals and personal care products (PPCPs) substances were selected as pollutants in this study. The effects of the removal of these pollutants and the microbial succession process in a granular sludge membrane bioreactor (GMBR) were investigated. Results showed that wastewater containing PPCPs influenced the performance of granular sludge. The removal of the five PPCPs from the GMBR had different effects. The removal rates of prednisolone, norfloxacin and naproxen reached 98.5, 87.8 and 84 %, respectively. The degradation effect in the GMBR system was relatively lower for sulphamethoxazole and ibuprofen, with removal efficiency rates of 79.8 and 63.3 %, respectively. Furthermore, the microbial community structure and diversity variation of the GMBR were analysed via high-throughput sequencing technology. The results indicated the structural and functional succession of the microbial community based on the GMBR process. The results indicate the key features of bacteria with an important role in drug degradation.

  7. Simultaneous removal of COD and ammonium from landfill leachate using an anaerobic-aerobic moving-bed biofilm reactor system.

    PubMed

    Chen, Sheng; Sun, Dezhi; Chung, Jong-Shik

    2008-01-01

    The performance of a moving-bed biofilm reactor (MBBR) system with an anaerobic-aerobic arrangement was investigated to treat landfill leachate for simultaneous removal of COD and ammonium. It was found that the anaerobic MBBR played a major role in COD removal due to methanogenesis, and the aerobic MBBR acted as COD-polishing and ammonium removal step. The contribution of the anaerobic MBBR to total COD removal efficiency reached 91% at an organic loading rate (OLR) of 4.08 kgCOD/(m3d), and gradually decreased to 86% when feed OLR was increased to 15.70 kgCOD/(m3d). Because of the complementary function of the aerobic reactor, the total COD removal efficiency of the system had a slight decrease from 94% to 92% even though the feed OLR was increased from 4.08 to 15.70 kgCOD/(m3d). Hydraulic retention time (HRT) had a significant effect on NH+4-N removal; more than 97% of the total NH+4-N removal efficiency could be achieved when the HRT of the aerobic MBBR was more than 1.25 days. The anaerobic-aerobic system had a strong tolerance to shock loading. A decrease in COD removal efficiency of only 7% was observed when the OLR was increased by four times and shock duration was 24 h, and the system could recover the original removal efficiency in 3 days. The average sludge yield of the anaerobic reactor was estimated to be 0.0538 gVSS/gCOD rem.

  8. Simultaneous nitrification/denitrification and trace organic contaminant (TrOC) removal by an anoxic-aerobic membrane bioreactor (MBR).

    PubMed

    Phan, Hop V; Hai, Faisal I; Kang, Jinguo; Dam, Hoa K; Zhang, Ren; Price, William E; Broeckmann, Andreas; Nghiem, Long D

    2014-08-01

    Simultaneous nitrification/denitrification and trace organic contaminant (TrOC) removal during wastewater treatment by an integrated anoxic-aerobic MBR was examined. A set of 30 compounds was selected to represent TrOCs that occur ubiquitously in domestic wastewater. The system achieved over 95% total organic carbon (TOC) and over 80% total nitrogen (TN) removal. In addition, 21 of the 30 TrOCs investigated here were removed by over 90%. Low oxidation reduction potential (i.e., anoxic/anaerobic) regimes were conducive to moderate to high (50% to 90%) removal of nine TrOCs. These included four pharmaceuticals and personal care products (primidone, metronidazole, triclosan, and amitriptyline), one steroid hormone (17β-estradiol-17-acetate), one industrial chemical (4-tert-octylphenol) and all three selected UV filters (benzophenone, oxybenzone, and octocrylene). Internal recirculation between the anoxic and aerobic bioreactors was essential for anoxic removal of remaining TrOCs. A major role of the aerobic MBR for TOC, TN, and TrOC removal was observed.

  9. Anaerobic-aerobic sequencing bioreactors improve energy efficiency for treatment of personal care product industry wastes.

    PubMed

    Ahammad, S Z; Bereslawski, J L; Dolfing, J; Mota, C; Graham, D W

    2013-07-01

    Personal care product (PCP) industry liquid wastes contain shampoo residues, which are usually treated by aerobic activated sludge (AS). Unfortunately, AS is expensive for PCP wastes because of high aeration and energy demands, whereas potentially energy-positive anaerobic designs cannot meet effluent targets. Therefore, combined anaerobic-aerobic systems may be the best solution. Seven treatment systems were assessed in terms of energy and treatment performance for shampoo wastes, including one aerobic, three anaerobic (HUASB, AHR and AnCSTR) and three anaerobic-aerobic reactor designs. COD removals were highest in the HUASB-aerobic (87.9 ± 0.4%) and AHR-aerobic (86.8±0.5%) systems, which used 69.2% and 62.5% less energy than aerobic AS. However, actual methane production rates were low relative to theoretical in the UASB and AHR units (∼10% methane/COD removed) compared with the AnCSTR unit (∼70%). Anaerobic-aerobic sequence reactors show promise for treating shampoo wastes, but optimal designs depend upon whether methane production or COD removal is most important to operations.

  10. Post-treatment of the permeate of a submerged anaerobic membrane bioreactor (SAMBR) treating landfill leachate.

    PubMed

    Trzcinski, Antoine P; Ofoegbu, Nkechi; Stuckey, David C

    2011-01-01

    In this study, various methods were compared to reduce the Chemical Oxygen Demand (COD) content of stabilised leachate from a Submerged Anaerobic Membrane Bioreactor (SAMBR). It was found that Powdered Activated Carbon (PAC) resulted in greater COD removals (84 %) than Granular Activated Carbon (GAC-80 %), an ultrafiltration membrane of 1kDa (75 %), coagulation-flocculation with FeCl(3) and polyelectrolyte (45 %), FeCl(3) alone (32 %), and polymeric adsorbents such as XAD7HP (46 %) and XAD4 (32 %). Results obtained on the <1 kDa fraction showed that PAC and GAC had a similar adsorption efficiency of about 60 % COD removal, followed by XAD7HP (48 %), XAD4 (27 %) and then FeCl(3) (23 %). The post-treatment sequence UF+GAC would result in a final effluent with less than 100 mg COD/L. Size Exclusion Chromatography (SEC) revealed that the extent of adsorption of low MW compounds onto PAC was limited due to low MW hydrophilic compounds, whereas the kinetics of PAC adsorption depended mainly on the adsorption of high MW aromatics.

  11. Mitigation of nitrous oxide (N2 O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers.

    PubMed

    Yamashita, Takahiro; Yamamoto-Ikemoto, Ryoko; Yokoyama, Hiroshi; Kawahara, Hirofumi; Ogino, Akifumi; Osada, Takashi

    2015-03-01

    Mitigation of nitrous oxide (N2 O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2 O emission and avoiding NOx (NO3  + NO2 ) accumulation. The N2 O emission factor was 0.0003 g N2 O-N/gTN-load in the CF bioreactor compared to 0.03 gN2 O-N/gTN-load in an activated sludge reactor (AS reactor). N2 O and CH4 emissions from the CF reactor were 42 g-CO2 eq/m(3) /day, while those from the AS reactor were 725 g-CO2 eq/m(3) /day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4 -N, and accumulated an average of 14 mg/L of the NO3 -N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4 -N and accumulated an average 183 mg/L of the NO3 -N. NO2 -N was almost undetectable in both reactors.

  12. Extraction and application of starch-based coagulants from sago trunk for semi-aerobic landfill leachate treatment.

    PubMed

    Aziz, Hamidi Abdul; Sobri, Nur Izzati Mohamad

    2015-11-01

    Malaysia is one of the highest starch producers. In this study, sago starch was utilized as a natural coagulant aid to reduce the dosage of aluminum-based coagulant in leachate treatment. The potential of native sago trunk starch (NSTS) and commercial sago starch (CSS) was evaluated as sole coagulant and coagulant aid in the presence of polyaluminum chloride (PACl) in the removal of color, suspended solids (SS), NH3-N, turbidity, chemical oxygen demand, organic UV254, Cd, and Ni. Leachate was sampled from Pulau Burung Landfill Site, one of the semi-aerobic landfills in Malaysia. The optimum dosage for PACl in the presence of NSTS or CSS as coagulant aid was reduced from 3100 to 2000 mg/L. In the presence of 2000 mg/L PACl with 6000 mg/L NSTS and 2000 mg/L PACl with 5000 mg/L CSS, the removal performance for color, SS, and turbidity are 94.7, 99.2, and 98.9%, respectively. Similar results were obtained with the use of 3100 mg/L PACl alone. Therefore, CSS and NSTS can be used as coagulant aid.

  13. The impact of nanoparticles on aerobic degradation of municipal solid waste.

    PubMed

    Yazici Guvenc, Senem; Alan, Burcu; Adar, Elanur; Bilgili, Mehmet Sinan

    2017-04-01

    The amount of nanoparticles released from industrial and consumer products has increased rapidly in the last decade. These products may enter landfills directly or indirectly after the end of their useful life. In order to determine the impact of TiO2 and Ag nanoparticles on aerobic landfilling processes, municipal solid waste was loaded to three pilot-scale aerobic landfill bioreactors (80 cm diameter and 350 cm height) and exposed to TiO2 (AT) and Ag (AA) nanoparticles at total concentrations of 100 mg kg(-1) of solid waste. Aerobic landfill bioreactors were operated under the conditions about 0.03 L min(-1) kg(-1) aeration rate for 250 days, during which the leachate, solid waste, and gas characteristics were measured. The results indicate that there was no significant difference in the leachate characteristics, gas constituents, solid quality parameters, and temperature variations, which are the most important indicators of landfill operations, and overall aerobic degradation performance between the reactors containing TiO2 and Ag nanoparticles, and control (AC) reactor. The data also indicate that the pH levels, ionic strength, and the complex formation capacity of nanoparticles with Cl(-) ions can reduce the toxicity effects of nanoparticles on aerobic degradation processes. The results suggest that TiO2 and Ag nanoparticles at concentrations of 100 mg kg(-1) of solid waste do not have significant impacts on aerobic biological processes and waste management systems.

  14. Targeted modification of organic components of municipal solid waste by short-term pre-aeration and its enhancement on anaerobic degradation in simulated landfill bioreactors.

    PubMed

    Ni, Zhe; Liu, Jianguo; Girotto, Francesca; Cossu, Raffaello; Qi, Guangxia

    2016-09-01

    Pre-aeration is effective on regulating subsequent anaerobic degradation of municipal solid waste (MSW) with high organic fractions during landfilling. The strength of pre-aeration should be optimized to intentionally remove some easily biodegradable fractions while conserve bio-methane potential as much as possible. This study investigates the evolution of organic components in MSW during 2-14days pre-aeration process and its impacts on subsequent anaerobic degradation in simulated landfill bioreactors. Results showed that a 6-day pre-aeration enabled to develop a thermophilic stage, which significantly accelerated biodegradation of organics except lignocelluloses, with removal rates of 42.8%, 76.7% and 25.1% for proteins, carbohydrates and lipids, respectively. Particularly, ammonia from accelerated ammonification in the thermophilic stage neutralized VFAs generated from anaerobic landfilling. As a result, the MSW with 6-day pre-aeration obtained the highest methane yield 123.4NL/kg dry matter. Therefore, it is recommended to interrupt pre-aeration before its cooling stage to switch to anaerobic landfilling.

  15. Performance evaluation of an anaerobic/aerobic landfill-based digester using yard waste for energy and compost production

    SciTech Connect

    Yazdani, Ramin; Barlaz, Morton A.; Augenstein, Don; Kayhanian, Masoud; Tchobanoglous, George

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Biochemical methane potential decreased by 83% during the two-stage operation. Black-Right-Pointing-Pointer Net energy produced was 84.3 MWh or 46 kWh per million metric tons (Mg). Black-Right-Pointing-Pointer The average removal efficiency of volatile organic compounds (VOCs) was 96-99%. Black-Right-Pointing-Pointer The average removal efficiency of non-methane organic compounds (NMOCs) was 68-99%. Black-Right-Pointing-Pointer The two-stage batch digester proved to be simple to operate and cost-effective. - Abstract: The objective of this study was to evaluate a new alternative for yard waste management by constructing, operating and monitoring a landfill-based two-stage batch digester (anaerobic/aerobic) with the recovery of energy and compost. The system was initially operated under anaerobic conditions for 366 days, after which the yard waste was aerated for an additional 191 days. Off gas generated from the aerobic stage was treated by biofilters. Net energy recovery was 84.3 MWh, or 46 kWh per million metric tons of wet waste (as received), and the biochemical methane potential of the treated waste decreased by 83% during the two-stage operation. The average removal efficiencies of volatile organic compounds and non-methane organic compounds in the biofilters were 96-99% and 68-99%, respectively.

  16. Pharmaceuticals and personal care products in the leachates from a typical landfill reservoir of municipal solid waste in Shanghai, China: Occurrence and removal by a full-scale membrane bioreactor.

    PubMed

    Sui, Qian; Zhao, Wentao; Cao, Xuqi; Lu, Shuguang; Qiu, Zhaofu; Gu, Xiaogang; Yu, Gang

    2017-02-05

    Knowledge on the pharmaceuticals and personal care products (PPCPs) in landfill leachates, which are an important source of PPCPs in the environment, was very limited. Hence, four sampling campaigns were conducted to determine eighteen PPCPs in the landfill leachates from a landfill reservoir in Shanghai. Five of the target PPCPs were first included in a landfill leachate study. Additionally, their removal from landfill leachates by a full-scale membrane bioreactor (MBR) was illustrated. The results showed fourteen out of eighteen PPCPs were detectable in at least one sampling campaign and achieved individual concentrations ranging from 0.39 to 349μg/L in the landfill leachates. Some PPCPs exhibited higher contamination levels than those reported in other countries. Good removal of PPCPs by MBR led to a largely reduced contamination level (landfill leachates, which was, however, still much higher than those in municipal wastewaters in Shanghai. To the best of our knowledge, this is the first report on the removal of PPCPs in landfill leachates. The findings emphasized the necessity to further study the PPCPs in the landfill leachates in China and the requirement to enhance their removal in the landfill leachates.

  17. Case study of an MBT plant producing SRF for cement kiln co-combustion, coupled with a bioreactor landfill for process residues.

    PubMed

    Grosso, Mario; Dellavedova, Stefano; Rigamonti, Lucia; Scotti, Sergio

    2016-01-01

    The paper describes the performances of the energy recovery pathway from the residual waste based on the production of a Solid Recovered Fuel (SRF) to be exploited via co-combustion in a cement kiln. The SRF is produced in a single stream Mechanical-Biological Treatment plant, where bio-drying of the waste is followed by mechanical refining in order to fulfil the quality requirements by the cement kilns. Peculiar of this MBT is the fact that sorting residues are disposed in a nearby landfill, managed according to a bioreactor approach, where landfill gas is collected for electric energy recovery. A detailed mass and energy balance of the system is presented based on one year operational data, followed by its Life Cycle Assessment. Results show that the system is energetically and environmentally effective, with most of the impacts being more than compensated by the savings of materials and energy. Major role in determining such outcome is the displacement of petcoke in the cement kiln, both in terms of its fossil CO2 emissions and of its life cycle impacts, including the trans-oceanic transport. To check the robustness of the results, two sensitivity analyses are performed on the landfill gas collection efficiency and on the avoided electric energy mix.

  18. Application of response surface methodology (RSM) for optimization of semi-aerobic landfill leachate treatment using ozone

    NASA Astrophysics Data System (ADS)

    Abu Amr, Salem S.; Aziz, Hamidi Abdul; Bashir, Mohammed J. K.

    2014-09-01

    The removal efficiencies for chemical oxygen demand (COD), ammoniacal nitrogen (NH3-N), and color, as well as ozone consumption (OC) from the Malaysian semi-aerobic landfill stabilized leachate using ozone reactor, were investigated. Central composite design with response surface methodology was applied to evaluate the interaction and relationship between operating variables (i.e., ozone dosage, COD concentration, and reaction time) and to develop the optimum operating condition. Based on statistical analysis, Quadratic models for the four responses (COD, NH3-N, color, and OC) proved to be significant with very low probability values (<0.0001). The obtained optimum conditions were 70 g/m3 ozone, 250 mg/l COD, and 60 min reaction time. The results obtained by the predicted model were 26.7, 7.1, and 92 % removal for COD, NH3-N, and color, respectively, with 9.42 (kgO3/kg COD) OC. The predicted results fitted well with the results of the laboratory experiment.

  19. Microbial community structure and pharmaceuticals and personal care products removal in a membrane bioreactor seeded with aerobic granular sludge.

    PubMed

    Xia, Zhao; Xiao-chun, Wang; Zhong-lin, Chen; Hao, Xu; Qing-fang, Zhang

    2015-01-01

    A process involving the use of membrane bioreactor seeded with aerobic granular sludge (GMBR) was applied to the treatment of sewage containing pharmaceuticals and personal care products (PPCPs). The removal effects of five kinds of medicines in the reactor were investigated, and the microbial communities were constructed by polymerase chain reaction and denaturing gradient gel electrophoresis. We also determined the effects of different sludge retention and hydraulic retention times (SRT and HRT, respectively) and influent organic loading on GMBR's efficiency in processing sewage containing PPCPs. The removal effects of the GMBR on five PPCPs varied. Using the GMBR, the removal rates of prednisolone, naproxen and norfloxacin were 98.56, 84.02 and 87.85%, respectively. The removal rates of sulfamethoxazole and ibuprofen were 77.83 and 63.32%, respectively. In the system, PPCP drugs had relatively less effect on microbial diversity. A certain succession was observed in the structural variation of microbial species in the GMBR. Microorganisms that can degrade PPCPs gradually accumulated, and antibiotic-resistant microorganisms, such as Firmicutes sp., Aeromonas sp. and Nitrospira sp., served a key function in the treatment of sewage containing antibiotics. Long SRT and HRT during the GMBR process can facilitate the removal of most PPCPs. The system efficiently removed PPCPs at high influent organic loading.

  20. Conventional and thermophilic aerobic treatability of high strength oily pet food wastewater using membrane-coupled bioreactors.

    PubMed

    Kurian, R; Acharya, C; Nakhla, G; Bassi, A

    2005-11-01

    Although thermophilic treatment systems have recently gained considerable interest, limited information exists on the comparative performances of membrane-coupled bioreactors (MBR) at thermophilic and conventional conditions. In this study aerobic MBRs operating at room temperature (20 degrees C) and at lower thermophilic range (45 degrees C) were investigated for the treatment of dissolved air flotation (DAF) pretreated pet food wastewater. The particular wastewater is characterized by oil and grease (O & G) concentrations as high as 6 g/L, COD of 51 g/L, BOD of 16 g/L and volatile fatty acid (VFA) of 8.3 g/L. The performances of the two systems in terms of COD, BOD and O & G removal at varying hydraulic retention time (HRT) are compared. COD removal efficiencies in the thermophilic MBR varied from 75% to 98% and remained constant at 94% in the conventional MBR. The O & G removal efficiencies were 66-86% and 98% in the thermophilic and conventional MBR, respectively. Interestingly, high concentrations of VFA were recorded, equivalent to 50-73% of total COD, in the thermophilic MBR effluent. The observed yield in the thermophilic MBR was 40% of that observed in the conventional MBR.

  1. Integrated thermophilic submerged aerobic membrane bioreactor and electrochemical oxidation for pulp and paper effluent treatment--towards system closure.

    PubMed

    Qu, X; Gao, W J; Han, M N; Chen, A; Liao, B Q

    2012-07-01

    A novel integrated thermophilic submerged aerobic membrane bioreactor (TSAMBR) and electrochemical oxidation (EO) technology was developed for thermomechanical pulping pressate treatment with the aim of system closure. The TSAMBR was able to achieve a chemical oxygen demand (COD) removal efficiency of 88.6 ± 1.9-92.3 ± 0.7% under the organic loading rate of 2.76 ± 0.13-3.98 ± 0.23 kg COD/(m(3) d). An optimal hydraulic retention time (HRT) of 1.1 ± 0.1d was identified for COD removal. Cake formation was identified as the dominant mechanism of membrane fouling. The EO of the TSAMBR permeate was performed using a Ti/SnO(2)-Sb(2)O(5)-IrO(2) electrode. After 6-h EO, a complete decolourization was achieved and the COD removal efficiency was increased to 96.2 ± 1.2-98.2 ± 0.3%. The high-quality effluent produced by the TSAMBR-EO system can be reused as process water for system closure in pulp and paper mill.

  2. Characterization of a joint recirculation of concentrated leachate and leachate to landfills with a microaerobic bioreactor for leachate treatment.

    PubMed

    He, Ruo; Wei, Xiao-Meng; Tian, Bao-Hu; Su, Yao; Lu, Yu-Lan

    2015-12-01

    With comparison of a traditional landfill, a joint recirculation of concentrated leachate and leachate to landfills with or without a microaerobic reactor for leachate treatment was investigated in this study. The results showed that the joint recirculation of concentrated leachate and leachate with a microaerobic reactor for leachate treatment could not only utilize the microaerobic reactor to buffer the fluctuation of quality and quantity of leachate during landfill stabilization, but also reduce the inhibitory effect of acidic pH and high concentrations of ammonium in recycled liquid on microorganisms and accelerate the degradation of landfilled waste. After 390 days of operation, the discharge of COD and total nitrogen (TN) from the landfill with leachate pretreatment by a microaerobic reactor was 7.4 and 0.9 g, respectively, which accounted for 0.7% and 2.6% of COD, 1.9% and 7.5% of the TN discharge from the landfills without recirculation and directly recirculated with leachate and concentrated leachate, respectively. The degradation of the organic matter and biodegradable matter (BDM) in the landfill reactors could fit well with the first-order kinetics. The highest degradation of the organic matter and BDM was observed in the joint recirculation system with a microaerobic reactor for leachate treatment with the degradation constant of the first-order kinetics of 0.001 and 0.002.

  3. Semi-aerobic stabilized landfill leachate treatment by ion exchange resin: isotherm and kinetic study

    NASA Astrophysics Data System (ADS)

    Zamri, Mohd Faiz Muaz Ahmad; Kamaruddin, Mohamad Anuar; Yusoff, Mohd Suffian; Aziz, Hamidi Abdul; Foo, Keng Yuen

    2015-03-01

    This study was carried out to investigate the treatability of ion exchange resin (Indion MB 6 SR) for the removal of chromium (VI), aluminium (III), zinc (II), copper (II), iron (II), and phosphate (PO4)3-, chemical oxygen demand (COD), ammonia nitrogen (NH3-N) and colour from semi-aerobic stabilized leachate by batch test. A range of ion exchange resin dosage was tested towards the removal efficiency of leachate parameters. It was observed that equilibrium data were best represented by the Langmuir model for metal ions and Freundlich was ideally fit for COD, NH3-N and colour. Intra particle diffusion model, pseudo first-order and pseudo second-order isotherm models were found ideally fit with correlation of the experimental data. The findings revealed that the models could describe the ion exchange kinetic behaviour efficiently, which further suggests comprehensive outlook for the future research in this field.

  4. Aerobic biological treatment of synthetic municipal wastewater in membrane-coupled bioreactors.

    PubMed

    Klatt, Christian G; LaPara, Timothy M

    2003-05-05

    Membrane-coupled bioreactors (MBRs) offer many benefits compared to conventional biological wastewater treatment systems; however, their performance characteristics are poorly understood. Laboratory-scale MBRs were used to study bacterial adaptations in physiology and community structure. MBRs were fed a mixture of starch, gelatin, and polyoxyethylene-sorbitan monooleate to simulate the polysaccharide, protein, and lipid components of municipal wastewater. Physiological adaptations were detected by measuring ectoenzyme activity while structural dynamics were studied by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments. As cell biomass accumulated in the MBRs, pollutant removal efficiency initially improved and then stabilized with respect to effluent concentrations of chemical oxygen demand, protein, and carbohydrate. Comparison of the MBR effluent to filtered reactor fluid indicated that a portion of the observed pollutant removal was due to filtration by the membrane rather than microbial activity. The rates of ectoenzyme-mediated polysaccharide (alpha-glucosidase) and protein (leucine aminopeptidase) hydrolysis became relatively constant once pollutant removal efficiency stabilized. However, the maximum rate of lipid hydrolysis (heptanoate esterase) concomitantly increased more than 10-fold. Similarly, alpha-glucosidase and leucine aminopeptidase ectoenzyme affinities were relatively constant, while the heptanoate esterase affinity increased more than 30-fold. Community analysis revealed that a substantial community shift occurred within the first 7 days of operation. A Flavobacterium-like bacterial population dominated the community (>50% of total band intensity) and continued to do so for the remainder of the experiment.

  5. Integration of aerobic granular sludge and mesh filter membrane bioreactor for cost-effective wastewater treatment.

    PubMed

    Li, Wen-Wei; Wang, Yun-Kun; Sheng, Guo-Ping; Gui, Yong-Xin; Yu, Lei; Xie, Tong-Qing; Yu, Han-Qing

    2012-10-01

    Conventional MBR has been mostly based on floc sludge and the use of costly microfiltration membranes. Here, a novel aerobic granule (AG)-mesh filter MBR (MMBR) process was developed for cost-effective wastewater treatment. During 32-day continuous operation, a predominance of granules was maintained in the system, and good filtration performance was achieved at a low trans-membrane pressure (TMP) of below 0.025 m. The granules showed a lower fouling propensity than sludge flocs, attributed to the formation of more porous biocake layer at mesh surface. A low-flux and low-TMP filtration favored a stable system operation. In addition, the reactor had high pollutant removal efficiencies, with a 91.4% chemical oxygen demand removal, 95.7% NH(4)(+) removal, and a low effluent turbidity of 4.1 NTU at the stable stage. This AG-MMBR process offers a promising technology for low-cost and efficient treatment of wastewaters.

  6. Influence of sludge retention time and temperature on the sludge removal in a submerged membrane bioreactor: comparative study between pure oxygen and air to supply aerobic conditions.

    PubMed

    Rodríguez, F A; Leyva-Díaz, J C; Reboleiro-Rivas, P; González-López, J; Hontoria, E; Poyatos, J M

    2014-01-01

    Performance of a bench-scale wastewater treatment plant, which consisted of a membrane bioreactor, was monitored daily using pure oxygen and air to supply aerobic conditions with the aim of studying the increases of the aeration and sludge removal efficiencies and the effect of the temperature. The results showed the capacity of membrane bioreactor systems for removing organic matter. The alpha-factors of the aeration were determined for six different MLSS concentrations in order to understand the system working when pure oxygen and air were used to supply aerobic conditions in the system. Aeration efficiency was increased between 30.7 and 45.9% when pure oxygen was used in the operation conditions (a hydraulic retention time of 12 h and MLSS concentrations between 4,018 and 11,192 mg/L). Sludge removal efficiency increased incrementally, from 0.2 to 1.5% when pure oxygen was used at low sludge retention time and from 1.5% to 15.4% at medium sludge retention time when temperature conditions were lower than 20°C. Moreover, the difference between calculated and experimental sludge retention time was lesser when pure oxygen was used to provide aerobic conditions, so the influence of the temperature decreased when the pure oxygen was used. These results showed the convenience of using pure oxygen due to the improvement in the performance of the system.

  7. Performances of anaerobic and aerobic membrane bioreactors for the treatment of synthetic textile wastewater.

    PubMed

    Yurtsever, Adem; Sahinkaya, Erkan; Aktaş, Özgür; Uçar, Deniz; Çınar, Özer; Wang, Zhiwei

    2015-09-01

    This study aims at comparatively evaluating anaerobic and aerobic MBRs for the treatment of azo-dye containing synthetic wastewater. Also, the filtration performances of AnMBR and AeMBR were compared under similar operating conditions. In both MBRs, high COD removal efficiencies were observed. Although almost complete color removal was observed in AnMBR, only partial (30-50%) color removal was achieved in AeMBR. AnMBR was successfully operated up to 9 L/(m(2)h) (LMH) and no chemical cleaning was required at 4.5 LMH for around 50 days. AeMBR was operated successfully up to 20 LMH. The filtration resistance of AnMBR was generally higher compared to AeMBR although reversible fouling rates were comparable. In both MBRs, offline chemical cleaning with NaOCl and sulfuric acid almost completely removed irreversible fouling and the resistances of chemically cleaned membranes were close to those of new membranes.

  8. Dynamic modeling of biodegradation and volatilization of hazardous aromatic substances in aerobic bioreactor.

    PubMed

    Mozo, I; Lesage, G; Yin, J; Bessiere, Y; Barna, L; Sperandio, M

    2012-10-15

    The aerobic biological process is one of the best technologies available for removing hazardous organic substances from industrial wastewaters. But in the case of volatile organic compounds (benzene, toluene, ethylbenzene, p-xylene, naphthalene), volatilization can contribute significantly to their removal from the liquid phase. One major issue is to predict the competition between volatilization and biodegradation in biological process depending on the target molecule. The aim of this study was to develop an integrated dynamic model to evaluate the influence of operating conditions, kinetic parameters and physical properties of the molecule on the main pathways (biodegradation and volatilization) for the removal of Volatile Organic Compounds (VOC). After a comparison with experimental data, sensitivity studies were carried out in order to optimize the aerated biological process. Acclimatized biomass growth is limited by volatilization, which reduces the bioavailability of the substrate. Moreover, the amount of biodegraded substrate is directly proportional to the amount of active biomass stabilized in the process. Model outputs predict that biodegradation is enhanced at high SRT for molecules with low H and with a high growth rate population. Air flow rate should be optimized to meet the oxygen demand and to minimize VOC stripping. Finally, the feeding strategy was found to be the most influential operating parameter that should be adjusted in order to enhance VOC biodegradation and to limit their volatilization in sequencing batch reactors (SBR).

  9. A two-stage aerobic/anaerobic denitrifying horizontal bioreactor designed for treating ammonium and H(2)S simultaneously.

    PubMed

    Chinalia, F A; Garbossa, L H P; Rodriguez, J A; Lapa, K R; Foresti, E

    2012-11-01

    A two-stage bioreactor was operated for a period of 140 days in order to develop a post-treatment process based on anaerobic bioxidation of sulfite. This process was designed for simultaneously treating the effluent and biogas of a full-scale UASB reactor, containing significant concentrations of NH(4) and H(2)S, respectively. The system comprised of two horizontal-flow bed-packed reactors operated with different oxygen concentrations. Ammonium present in the effluent was transformed into nitrates in the first aerobic stage. The second anaerobic stage combined the treatment of nitrates in the liquor with the hydrogen sulfide present in the UASB-reactor biogas. Nitrates were consumed with a significant production of sulfate, resulting in a nitrate removal rate of 0.43 kgNm(3)day(-1) and ≥92 % efficiency. Such a removal rate is comparable to those achieved by heterotrophic denitrifying systems. Polymeric forms of sulfur were not detected (elementary sulfur); sulfate was the main product of the sulfide-based denitrifying process. S-sulfate was produced at a rate of about 0.35 kgm(3)day(-1). Sulfur inputs as S-H(2)S were estimated at about 0.75 kgm(3)day(-1) and Chemical Oxygen Demand (COD) removal rates did not vary significantly during the process. DGGE profiling and 16S rRNA identified Halothiobacillus-like species as the key microorganism supporting this process; such a strain has not yet been previously associated with such bioengineered systems.

  10. [Impact of Salinity on Leachate Treatment and N2O Releases from Semi-aerobic Aged-refuse Bioreactor].

    PubMed

    Li, Wei-hua; Sun, Ying-jie; Liu, Zi-liang; Ma, Qiang; Yang, Qiang

    2016-02-15

    Semi-aerobic Aged-refuse Bioreactor (SAARB) has a good effect on nitrogen removal in leachate, but a strong greenhouse gas (N2O) was generated during the nitrification and denitrification process. The effect of salinity (7-30 g x L(-1)) on the leachate treatment and the N2O production from SAARB system was investigated. Experimental results showed that salinity ranging from 7 to 30 g x L(-1) had no significant effect on COD removal, and the removal efficiency was always more than 85%. On the contrary, it had a strong influence on the removal of nitrogen. The removal efficiencies of NH4+ -N and TN decreased from 98. 23% and 91.48% at 7 g x L(-1) salt to 31.75% and 34.24% at 30 g x L(-1) salt, respectively. Moreover, there was significant nitrite (NO2- -N) accumulation in the presence of 30 g x L(-1) salt. Meanwhile, salinity had different inhibition strength on nitrification and denitrification bacteria, and the order of inhibition strength was as follows: nitrification bacteria > denitrification bacteria. In addition, the N2O production increased with salinity concentration, and the highest N2O accumulation (1397 microg +/- 369.88 microg) was observed with addition of 30 g x L(-1) salt, which accounted for 8.87%o of the total nitrogen removal. Meanwhile, it was 6-117 times higher in the presence of 30 g x L(-1) salt than that in low salinity conditions (7-20 g x L(-1)). And the peak time of the N2O production showed a delayed trend. These results indicated that salinity recirculation in leachate had a negative effect on the nitrogen removal and N2O production. Overall, salinity seemed to be a key parameter during leachate recirculation.

  11. Complete degradation of the azo dye Acid Orange-7 and bioelectricity generation in an integrated microbial fuel cell, aerobic two-stage bioreactor system in continuous flow mode at ambient temperature.

    PubMed

    Fernando, Eustace; Keshavarz, Taj; Kyazze, Godfrey

    2014-03-01

    In this study, the commercially used model azo dye Acid Orange-7 (AO-7) was fully degraded into less toxic intermediates using an integrated microbial fuel cell (MFC) and aerobic bioreactor system. The integrated bioreactor system was operated at ambient temperature and continuous-flow mode. AO-7 loading rate was varied during experiments from 70gm(-3)day(-1) to 210gm(-3)day(-1). Colour and soluble COD removal rates reached>90% under all AO-7 loading rates. The MFC treatment stage prompted AO-7 to undergo reductive degradation into its constituent aromatic amines. HPLC-MS analysis of metabolite extracts from the aerobic stage of the bioreactor system indicated further oxidative degradation of the resulting aromatic amines into simpler compounds. Bioluminescence based Vibrio fischeri ecotoxicity testing demonstrated that aerobic stage effluent exhibited toxicity reductions of approximately fivefold and ten-fold respectively compared to the dye wastewater influent and MFC-stage effluent.

  12. Remediation of pharmaceuticals and personal care products using an aerobic granular sludge sequencing bioreactor and microbial community profiling using Solexa sequencing technology analysis.

    PubMed

    Zhao, Xia; Chen, Zhonglin; Wang, Xiaochun; Li, Jinchunzi; Shen, Jimin; Xu, Hao

    2015-03-01

    Recently, a new type of organic pollution derived from pharmaceuticals and personal care products (PPCPs) is gradually on the rise. Wastewater treatment to remove PPCPs was investigated using an aerobic granular sludge sequencing bioreactor (GSBR). After optimization of influent organic load, hydraulic shear stress, sludge settling time, etc., aerobic granular sludge was analyzed for its physiological and biochemical characteristics and tested for its efficacy to remove PPCPs wastewater. The granular sludge effectively removed some but not all of the PPCPs tested; removal correlated with the microbial profiles in the granules, as assessed using Solexa sequencing technology. Sequencing revealed the presence of five phylogenetic groups: Proteobacteria, Bacteroidetes, Betaproteobacteria, an unclassified genus, and Zoogloea. The results demonstrated changes in the microbial profiles with time in response to the presence of PPCPs. The effects of PPCPs on microbial communities in granular sludge process are discussed.

  13. Effects of high organic load on amoA and nirS gene diversity of an intermittently aerated and fed membrane bioreactor treating landfill leachate.

    PubMed

    Remmas, Nikolaos; Melidis, Paraschos; Katsioupi, Efthymia; Ntougias, Spyridon

    2016-11-01

    The effects of external carbon source addition on the nitrification and denitrification process were investigated in an intermittently aerated and fed membrane bioreactor treating landfill leachate by recording system performance, and amoA and nirS diversity dynamics using pyrosequencing. By adding 950mg/L glycerol, denitrification was optimized, resulting in total nitrogen removal efficiency of 81.0±2.4%. Under these conditions, amoA diversity was dominated by genotypes related to Nitrosomonas europaea, while increase in leachate's content and in glycerol addition by 50% led to irreversible inhibition of nitrification and enhanced ammonia accumulation, causing a severe suppression of Nitrosomonas and an increase in the relative abundance of Nitrosospira. However, this increase not only affected ammonia oxidizers, but also caused a massive shift in denitrifying community structure, resulting in the suppression of Arenimonas metalli-, Candidatus Accumulibacter- and Sulfuritalea hydrogenivorans-nirS related genotypes and the predominance of nirS-associated with Acidovorax and Thaurea sp.

  14. Biological wastewater treatment by a bioreactor with repeated coupling of aerobes and anaerobes aiming at on-site reduction of excess sludge.

    PubMed

    Yu, Anfeng; Feng, Quan; Liu, Zehua; Zhou, Yunan; Xing, Xin-Hui

    2006-01-01

    Activated sludge has been widely used in wastewater treatment throughout the world. However, the biggest disadvantage of this method is the by-production of excess sludge in a large amount, resulting in difficulties in operation and high costs for wastewater treatment. Technological innovations for wastewater treatment capable of reducing excess sludge have thus become research topics of interest in recent years. In our present research, we developed a new biological wastewater treatment process by repeated coupling of aerobes and anaerobes (rCAA) to reduce the excess sludge during the treatment of wastewater. During 460-day continuous running, COD (300-700 mg/L) and TOC (100-350 mg/L) were effectively removed, of which the removal rate was above 80 and 90%, respectively. SS in the effluent was 13 mg/L on average in the rCAA bioreactor without a settling tank. The on-site reduction of the excess sludge in the rCAA might be contributed by several mechanisms. The degradation of the grown aerobes after moving into the anaerobic regions was considered to be one of the most important factors. Besides, the repeatedly coupling of aerobes and anaerobes could also result in a complex microbial community with more metazoans and decoupling of the microbial anabolism and catabolism.

  15. Enhanced poly(γ-glutamic acid) fermentation by Bacillus subtilis NX-2 immobilized in an aerobic plant fibrous-bed bioreactor.

    PubMed

    Xu, Zongqi; Feng, Xiaohai; Zhang, Dan; Tang, Bao; Lei, Peng; Liang, Jinfeng; Xu, Hong

    2014-03-01

    To enhance poly(γ-glutamic acid) (PGA) production, a novel aerobic plant fibrous-bed bioreactor (APFB) was constructed for immobilized fermentation. Based on the analysis of the kinetics of immobilized-cell fermentation using the APFB and conventional free-cell fermentation, immobilized-cell fermentation exhibited more efficient PGA production. Furthermore, repeated fed-batch cultures for PGA production were conducted to evaluate the stability of the APFB system. Average final PGA concentration and productivity of 71.21±0.83g/L and 1.246±0.008g/L/h were respectively achieved by cells immobilized in bagasse during APFB, which was reused eight times over a period of 457±18h. Analysis of the membrane phospholipids and the key enzyme activities indicated that APFB-adapted cells had better productivity than original cells. Thus, this study demonstrated the significant potential of the APFB culture system in future industrial applications.

  16. CFD Study of Full-Scale Aerobic Bioreactors: Evaluation of Dynamic O2 Distribution, Gas-Liquid Mass Transfer and Reaction

    SciTech Connect

    Humbird, David; Sitaraman, Hariswaran; Stickel, Jonathan; Sprague, Michael A.; McMillan, Jim

    2016-11-18

    If advanced biofuels are to measurably displace fossil fuels in the near term, they will have to operate at levels of scale, efficiency, and margin unprecedented in the current biotech industry. For aerobically-grown products in particular, scale-up is complex and the practical size, cost, and operability of extremely large reactors is not well understood. Put simply, the problem of how to attain fuel-class production scales comes down to cost-effective delivery of oxygen at high mass transfer rates and low capital and operating costs. To that end, very large reactor vessels (>500 m3) are proposed in order to achieve favorable economies of scale. Additionally, techno-economic evaluation indicates that bubble-column reactors are more cost-effective than stirred-tank reactors in many low-viscosity cultures. In order to advance the design of extremely large aerobic bioreactors, we have performed computational fluid dynamics (CFD) simulations of bubble-column reactors. A multiphase Euler-Euler model is used to explicitly account for the spatial distribution of air (i.e., gas bubbles) in the reactor. Expanding on the existing bioreactor CFD literature (typically focused on the hydrodynamics of bubbly flows), our simulations include interphase mass transfer of oxygen and a simple phenomenological reaction representing the uptake and consumption of dissolved oxygen by submerged cells. The simulations reproduce the expected flow profiles, with net upward flow in the center of column and downward flow near the wall. At high simulated oxygen uptake rates (OUR), oxygen-depleted regions can be observed in the reactor. By increasing the gas flow to enhance mixing and eliminate depleted areas, a maximum oxygen transfer (OTR) rate is obtained as a function of superficial velocity. These insights regarding minimum superficial velocity and maximum reactor size are incorporated into NREL's larger techno-economic models to supplement standard reactor design equations.

  17. A comparative study of leachate quality and biogas generation in simulated anaerobic and hybrid bioreactors.

    PubMed

    Xu, Qiyong; Tian, Ying; Wang, Shen; Ko, Jae Hac

    2015-07-01

    Research has been conducted to compare leachate characterization and biogas generation in simulated anaerobic and hybrid bioreactor landfills with typical Chinese municipal solid waste (MSW). Three laboratory-scale reactors, an anaerobic (A1) and two hybrid bioreactors (C1 and C2), were constructed and operated for about 10months. The hybrid bioreactors were operated in an aerobic-anaerobic mode with different aeration frequencies by providing air into the upper layer of waste. Results showed that the temporary aeration into the upper layer aided methane generation by shortening the initial acidogenic phase because of volatile fatty acids (VFAs) reduction and pH increase. Chemical oxygen demand (COD) decreased faster in the hybrid bioreactors, but the concentrations of ammonia-nitrogen in the hybrid bioreactors were greater than those in the anaerobic control. Methanogenic conditions were established within 75d and 60d in C1 and C2, respectively. However, high aeration frequency led to the consumption of organic matters by aerobic degradation and resulted in reducing accumulative methane volume. The temporary aeration enhanced waste settlement and the settlement increased with increasing the frequency of aeration. Methane production was inhibited in the anaerobic control; however, the total methane generations from hybrid bioreactors were 133.4L/kgvs and 113.2L/kgvs. As for MSW with high content of food waste, leachate recirculation right after aeration stopped was not recommended due to VFA inhibition for methanogens.

  18. Design of top covers supporting aerobic in situ stabilization of old landfills - An experimental simulation in lysimeters

    SciTech Connect

    Hrad, Marlies; Huber-Humer, Marion; Wimmer, Bernhard; Reichenauer, Thomas G.

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Tested engineered covers as surrogate to gas extraction during and after in situ aeration. Black-Right-Pointing-Pointer Examined how covers influence gas emissions, water balance and leachate generation. Black-Right-Pointing-Pointer Investigated effect of top covers on air-distribution in waste mass during aeration. Black-Right-Pointing-Pointer We suggest criteria and cover design to meet the demands during and after aeration. Black-Right-Pointing-Pointer Such cover systems may offer greenhouse gas emission reduction also after active aeration. - Abstract: Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 Multiplication-Sign 2 Multiplication-Sign 3 m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH{sub 4} loadings up to 300 l CH{sub 4}/m{sup 2} d. In addition, the compost material provided high air permeability

  19. The dependence of the methylation of mercury on the landfill stabilization process and implications for the landfill management.

    PubMed

    Chai, Xiaoli; Hao, Yongxia; Li, Zhonggen; Zhu, Wei; Zhao, Wentao

    2015-01-01

    Mercury species and other chemical characteristics of the leachate from anaerobic and semi-aerobic landfills were analyzed to investigate the factors that control mercury methylation during the landfill stabilization process. At the early landfill stage, the total mercury (THg) and the monomethyl mercury (MMHg) released rapidly and significantly, the THg concentration of the semi-aerobic landfill leachate was obviously higher than that of the anaerobic landfill leachate, while compared with the semi-aerobic landfill, the MMHg concentration in the anaerobic landfill was higher. As the landfill time increased, both of THg and MMHg concentration decreased quickly, the THg concentration in the anaerobic landfill was much higher than that in semi-aerobic landfill, while the MMHg concentration in the anaerobic landfill was lower than that in the semi-aerobic landfill. Generally, the concentrations of dimethyl mercury (DMHg) in the anaerobic landfill leachate were slightly higher than in the semi-aerobic landfill leachate during the stabilization process. A significant positive correlation was found between the DMHg concentrations and the pH value in anaerobic landfill leachate, but this correlation was opposite in the semi-aerobic landfill. The oxidative-reductive potential (ORP) condition was found to be the controlling factor of the methylation process during the early stage. However, the chemical characteristics, especially the TOC concentration, appeared to be the dominant factor affecting the methylation process as the landfill time increased.

  20. MOLECULAR AND CULTURAL METHODOLOGIES FOR ENUMERATING BACTERIA IN LANDFILL LEACHATES

    EPA Science Inventory

    Landfill bioreactor technology has been under investigation in the field for its potential economic and waste treatment benefits over conventional landfill systems. A better understanding of biological influences on the stabilization process is needed for incorporation into the e...

  1. Fluctuation of dissolved heavy metal concentrations in the leachate from anaerobic digestion of municipal solid waste in commercial scale landfill bioreactors: The effect of pH and associated mechanisms.

    PubMed

    Xie, S; Ma, Y; Strong, P J; Clarke, W P

    2015-12-15

    Heavy metals present in landfill leachate have infrequently been related to complete anaerobic degradation municipal solid waste (MSW) due to discrete ages of deposited MSW layers and leachate channelling in landfills. In this study, anaerobic digestion of MSW was performed in two enclosed 1000 tonne bioreactors using a unique flood and drain process. Leachates were characterised in terms of pH, soluble chemical oxygen demand, volatile fatty acids (VFAs), ammonium nitrogen and heavy metals over the entire course of digestion. All parameters, including pH, fluctuated during acidogenesis, acetogenesis and methanogenesis, which strongly impacted on the dynamics of dissolved heavy metal concentrations. The simulation of dissolution and precipitation processes indicated that metal sulphide precipitation was not a factor as metal concentrations exceeded solubility limits. The correlation of pH and dissolved heavy metal concentrations indicated that other, mechanisms were involved in the homogenised conditions within the bioreactors. Beside dissolution and precipitation, the main processes most likely involved in metal distributions were adsorption (Zn, Cu, Ni, Pb and Cd), complexation (Cr) or combinations of both process (As and Co).

  2. Microbial community structure and dynamics in a pilot-scale submerged membrane bioreactor aerobically treating domestic wastewater under real operation conditions.

    PubMed

    Molina-Muñoz, M; Poyatos, J M; Sánchez-Peinado, M; Hontoria, E; González-López, J; Rodelas, B

    2009-06-15

    A pilot scale submerged ultra-filtration membrane bioreactor (MBR) was used for the aerobic treatment of domestic wastewater over 9 months of year 2006 (28th March to 21st December). The MBR was installed at a municipal wastewater facility (EMASAGRA, Granada, Spain) and was fed with real wastewater. The experimental work was divided in 4 stages run under different sets of operation conditions. Operation parameters (total and volatile suspended solids, dissolved oxygen concentration) and environmental variables (temperature, pH, COD and BOD(5) of influent water) were daily monitored. In all the experiments conducted, the MBR generated an effluent of optimal quality complying with the requirements of the European Law (91/271/CEE 1991). A cultivation-independent approach (polymerase chain reaction-temperature gradient gel electrophoresis, PCR-TGGE) was used to analyze changes in the structure of the bacterial communities in the sludge. Cluster analysis of TGGE profiles demonstrated significant differences in community structure related to variations of the operation parameters and environmental factors. Canonical correspondence analysis (CCA) suggested that temperature, hydraulic retention time and concentration of volatile suspended solids were the factors mostly influencing community structure. 23 prominent TGGE bands were successfully reamplified and sequenced, allowing gaining insight into the identities of predominantly present bacterial populations in the sludge. Retrieved partial 16S-rRNA gene sequences were mostly related to the alpha-Proteobacteria, beta-Proteobacteria and gamma-Proteobacteria classes. The community established in the MBR in each of the four stages of operation significantly differed in species composition and the sludge generated displayed dissimilar rates of mineralization, but these differences did not influence the performance of the bioreactor (quality of the permeate). These data indicate that the flexibility of the bacterial community

  3. Landfill Gas Effects on Evapotranspirative Landfill Covers

    NASA Astrophysics Data System (ADS)

    Plummer, M. A.; Mattson, E.; Ankeny, M.; Kelsey, J.

    2005-05-01

    The performance of an evapotranspirative landfill cover can be adversely affected by transport of landfill gases to the plant root zone. Healthy plant communities are critical to the success and effectiveness of these vegetated landfill covers. Poor vegetative cover can result in reduced transpiration, increased percolation, and increased erosion regardless of the thickness of the cover. Visual inspections of landfill covers indicate that vegetation-free areas are not uncommon at municipal waste landfills. Data from soil profiles beneath these areas suggest that anaerobic conditions in the plant-rooting zone are controlling plant distribution. On the same landfill, aerobic conditions exist at similar depths beneath well-vegetated areas. The movement of methane and carbon dioxide, generated by degradation of organic wastes, into the overlying soil cover displaces oxygen in the root zone. Monitoring data from landfills in semi-arid areas indicate that barometric pumping can result in hours of anaerobic conditions in the root zone. Microbial consumption of oxygen in the root zone reduces the amount of oxygen available for plant root respiration but consumption of oxygen and methane also produce water as a reaction byproduct. This biogenic water production can be on the order of centimeters of water per year which, while increasing water availability, also has a negative feedback on transport of landfill gases through the cover. Accounting for these processes can improve evapotranspirative landfill cover design at other sites.

  4. Modeling microbiological and chemical processes in municipal solid waste bioreactor, Part I: Development of a three-phase numerical model BIOKEMOD-3P.

    PubMed

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

    2010-02-01

    The numerical computer models that simulate municipal solid waste (MSW) bioreactor landfills have mainly two components--a biodegradation process module and a multi-phase flow module. The biodegradation model describes the chemical and microbiological processes. The models available to date include predefined solid waste biodegradation reactions and participating species. Some of these models allow changing the basic composition of solid waste. In a bioreactor landfill several processes like anaerobic and aerobic solids biodegradation, nitrogen and sulfate related processes, precipitation and dissolution of metals, and adsorption and gasification of various anthropogenic organic compounds occur simultaneously. These processes may involve reactions of several species and the available biochemical models for solid waste biodegradation do not provide users with the flexibility to simulate these processes by choice. This paper presents the development of a generalized biochemical process model BIOKEMOD-3P which can accommodate a large number of species and process reactions. This model is able to simulate bioreactor landfill operation in a completely mixed condition, when coupled with a multi-phase model it will be able to simulate a full-scale bioreactor landfill. This generalized biochemical model can simulate laboratory and pilot-scale operations in order to determine biochemical parameters important for simulation of full-scale operations.

  5. Aerobic co-treatment of landfill leachate and domestic wastewater - are slowly biodegradable organics removed or simply diluted?

    PubMed

    Campos, R; Ferraz, F M; Vieira, E M; Povinelli, J

    2014-01-01

    This study investigated the co-treatment of landfill leachate/domestic wastewater in bench-scale activated sludge (AS) reactors to determine whether the slowly biodegradable organic matter (SBOM) was removed rather than diluted. The AS reactors were loaded with mixtures of raw leachate and leachate that was pretreated by air stripping. The tested volumetric ratios were 0%, 0.2%, 2% and 5%. For all of the tested conditions, the reactors performed better when pretreated leachate was used rather than raw leachate, and the best volumetric ratio was 2%. The following removals were obtained: 97% for the biochemical oxygen demand (BOD5,20), 79% for total suspended solids, 77% for dissolved organic carbon and 84% for soluble chemical oxygen demand. Most of the pretreated leachate SBOM (65%) was removed rather than diluted or adsorbed into the sludge, as confirmed by Fourier transform infrared (FTIR) spectroscopy analyses.

  6. Data Pre-Processing Method to Remove Interference of Gas Bubbles and Cell Clusters During Anaerobic and Aerobic Yeast Fermentations in a Stirred Tank Bioreactor

    NASA Astrophysics Data System (ADS)

    Princz, S.; Wenzel, U.; Miller, R.; Hessling, M.

    2014-11-01

    One aerobic and four anaerobic batch fermentations of the yeast Saccharomyces cerevisiae were conducted in a stirred bioreactor and monitored inline by NIR spectroscopy and a transflectance dip probe. From the acquired NIR spectra, chemometric partial least squares regression (PLSR) models for predicting biomass, glucose and ethanol were constructed. The spectra were directly measured in the fermentation broth and successfully inspected for adulteration using our novel data pre-processing method. These adulterations manifested as strong fluctuations in the shape and offset of the absorption spectra. They resulted from cells, cell clusters, or gas bubbles intercepting the optical path of the dip probe. In the proposed data pre-processing method, adulterated signals are removed by passing the time-scanned non-averaged spectra through two filter algorithms with a 5% quantile cutoff. The filtered spectra containing meaningful data are then averaged. A second step checks whether the whole time scan is analyzable. If true, the average is calculated and used to prepare the PLSR models. This new method distinctly improved the prediction results. To dissociate possible correlations between analyte concentrations, such as glucose and ethanol, the feeding analytes were alternately supplied at different concentrations (spiking) at the end of the four anaerobic fermentations. This procedure yielded low-error (anaerobic) PLSR models for predicting analyte concentrations of 0.31 g/l for biomass, 3.41 g/l for glucose, and 2.17 g/l for ethanol. The maximum concentrations were 14 g/l biomass, 167 g/l glucose, and 80 g/l ethanol. Data from the aerobic fermentation, carried out under high agitation and high aeration, were incorporated to realize combined PLSR models, which have not been previously reported to our knowledge.

  7. Kinetic study and oxygen transfer efficiency evaluation using respirometric methods in a submerged membrane bioreactor using pure oxygen to supply the aerobic conditions.

    PubMed

    Rodríguez, Francisco A; Poyatos, José M; Reboleiro-Rivas, Patricia; Osorio, Francisco; González-López, Jesús; Hontoria, Ernesto

    2011-05-01

    The performance of a wastewater bench-scale ultrafiltration membrane bioreactor (MBR) treatment plant using pure oxygen to supply the aerobic conditions for 95 days was studied. The results showed the capacity of the MBR systems to remove organic material under a hydraulic retention time of 12h and a sludge retention time of 39.91 days. Aeration represents its major power input; this is why the alpha-factor of the aeration and kinetic parameters (design parameters) were determined when the mixed liquid suspended solids (MLSS) was increased from 3420 to 12,600 mg/l in order to understand the system. An alpha-factor in the range 0.462-0.022 and the kinetic parameters measured with the respirometric method (K(M) of 73.954-3.647 mg/l, k(d) of 0.0142-0.104 day(-1), k(H) of 0.1266-0.655 day(-1), and the yield mean coefficient of 0.941) were obtained. Our study suggested significant changes in the behaviour of the biological system when the concentration of MLSS was increased.

  8. Characterisation of microbial floras and functional gene levels in an anaerobic/aerobic bio-reactor for the degradation of carboxymethyl cellulose.

    PubMed

    Ji, Guodong; Wang, Chen; Guo, Feng

    2013-04-01

    The current study determined the carboxymethyl cellulose (CMC) degradation efficiency, dominant microbial flora, eubacteria and archaebacteria characteristics, and expression levels of genes cel5A, cel6B, and bglC in an anaerobic/aerobic bio-reactor consisting of two-stage UASB (U1 and U2) and two-stage BAF (B1 and B2). The results showed that under three CMC loads, the CMC degradation efficiency of the UASB-BAF system was 91.25%, 80.44%, and 78.73%, respectively. At higher CMC loads, the degradation of cellulose and transformation to cellobiose in U1 was higher, while the transformation to glucose was lower. The results of DGGE and real-time PCR indicated that cellulose degradation bacteria are dominant in U1, cellulose degradation bacteria and cellulose degradation symbiosis bacteria are dominant in B1, and non-cellulose degradation symbiosis bacteria are dominant in both U2 and B2. The rate-limiting enzyme gene of cellulose degradation in U1, B1, and B2 is cel6B, but it is cel5A in U2.

  9. Metagenomic characterization of 'Candidatus Defluviicoccus tetraformis strain TFO71', a tetrad-forming organism, predominant in an anaerobic-aerobic membrane bioreactor with deteriorated biological phosphorus removal.

    PubMed

    Nobu, Masaru K; Tamaki, Hideyuki; Kubota, Kengo; Liu, Wen-Tso

    2014-09-01

    In an acetate-fed anaerobic-aerobic membrane bioreactor with deteriorated enhanced biological phosphorus removal (EBPR), Defluviicoccus-related tetrad-forming organisms (DTFO) were observed to predominate in the microbial community. Using metagenomics, a partial genome of the predominant DTFO, 'Candidatus Defluviicoccus tetraformis strain TFO71', was successfully constructed and characterized. Examining the genome confirmed the presence of genes related to the synthesis and degradation of glycogen and polyhydroxyalkanoate (PHA), which function as energy and carbon storage compounds. TFO71 and 'Candidatus Accumulibacter phosphatis' (CAP) UW-1 and CAP UW-2, representative polyphosphate-accumulating organisms (PAO), have PHA metabolism-related genes with high homology, but TFO71 has unique genes for PHA synthesis, gene regulation and granule management. We further discovered genes encoding DTFO polyphosphate (polyP) synthesis, suggesting that TFO71 may synthesize polyP under untested conditions. However, TFO71 may not activate these genes under EBPR conditions because the retrieved genome does not contain all inorganic phosphate transporters that are characteristic of PAOs (CAP UW-1, CAP UW-2, Microlunatus phosphovorus NM-1 and Tetrasphaera species). As a first step in characterizing EBPR-associated DTFO metabolism, this study identifies important differences between DTFO and PAO that may contribute to EBPR community competition and deterioration.

  10. Effects of ion exchange resins in different mobile ion forms on semi-aerobic landfill leachate treatment.

    PubMed

    Bashir, Mohammed J K; Aziz, Hamidi Abdul; Yusoff, Mohd Suffian; Huqe, A A M; Mohajeri, Soraya

    2010-01-01

    Landfill leachate is one of the major contamination sources. In this study, the ability of synthetic ion exchange resins which carry different mobile ion for removing color, chemical oxygen demand (COD), and ammonia nitrogen (NH(3)-N) from stabilized leachate was investigated. The synthetic resin INDION 225 Na as a cationic exchanger and INDION FFIP MB as an anionic exchanger were used in this study. INDION 225 Na was used in hydrogen form (H(+)) and in sodium form (Na(+)), while INDION FFIP MB resin was used in hydroxide form (OH(-)) and in calcium form (Cl(-)) form. The results indicated better removal of color, COD and NH(3)-N by using INDION 225 Na in H(+) as compared with Na(+) form, while no performance differences were observed by using INDION FFIP MB in OH(-) or Cl(-) form. Applying cationic resin followed by anionic resin achieved 97, 88 and 94, percent removal of color, COD and NH(3)-N. The residual amounts were 160 Pt-Co, 290 mg/L and 110 mg/L of color, COD and NH(3)-N respectively.

  11. Environmental assessment of solid waste landfilling technologies by means of LCA-modeling.

    PubMed

    Manfredi, Simone; Christensen, Thomas H

    2009-01-01

    By using life cycle assessment (LCA) modeling, this paper compares the environmental performance of six landfilling technologies (open dump, conventional landfill with flares, conventional landfill with energy recovery, standard bioreactor landfill, flushing bioreactor landfill and semi-aerobic landfill) and assesses the influence of the active operations practiced on these performances. The environmental assessments have been performed by means of the LCA-based tool EASEWASTE, whereby the functional unit utilized for the LCA is "landfilling of 1ton of wet household waste in a 10m deep landfill for 100 years". The assessment criteria include standard categories (global warming, nutrient enrichment, ozone depletion, photo-chemical ozone formation and acidification), toxicity-related categories (human toxicity and ecotoxicity) and impact on spoiled groundwater resources. Results demonstrate that it is crucially important to ensure the highest collection efficiency of landfill gas and leachate since a poor capture compromises the overall environmental performance. Once gas and leachate are collected and treated, the potential impacts in the standard environmental categories and on spoiled groundwater resources significantly decrease, although at the same time specific emissions from gas treatment lead to increased impact potentials in the toxicity-related categories. Gas utilization for energy recovery leads to saved emissions and avoided impact potentials in several environmental categories. Measures should be taken to prevent leachate infiltration to groundwater and it is essential to collect and treat the generated leachate. The bioreactor technologies recirculate the collected leachate to enhance the waste degradation process. This allows the gas collection period to be reduced from 40 to 15 years, although it does not lead to noticeable environmental benefits when considering a 100 years LCA-perspective. In order to more comprehensively understand the influence

  12. Sustainability Gaps in Municipal Solid Waste Management: The Case of Landfills

    DTIC Science & Technology

    2006-02-01

    disposal technologies , bioreactor and dry tomb landfills, in a 600-year time-horizon using two different discounting techniques: Constant conventional...Abstract: Our paper compares external effects of two municipal solid waste disposal technologies , bioreactor and dry tomb landfills, in a 600-year time...different types of landfills, i.e., the dry tomb technology and the bioreactor type for municipal solid waste disposal (section 2). This is followed

  13. A comparative study of leachate quality and biogas generation in simulated anaerobic and hybrid bioreactors

    SciTech Connect

    Xu, Qiyong; Tian, Ying; Wang, Shen; Ko, Jae Hac

    2015-07-15

    Highlights: • Temporary aeration shortened the initial acid inhibition phase for methanogens. • COD decreased faster in the hybrid bioreactor than that in the anaerobic control. • Methane generations from hybrid bioreactors were 133.4 L/kg{sub vs} and 113.2 L/kg{sub vs}. • MSW settlement increased with increasing the frequency of intermittent aeration. - Abstract: Research has been conducted to compare leachate characterization and biogas generation in simulated anaerobic and hybrid bioreactor landfills with typical Chinese municipal solid waste (MSW). Three laboratory-scale reactors, an anaerobic (A1) and two hybrid bioreactors (C1 and C2), were constructed and operated for about 10 months. The hybrid bioreactors were operated in an aerobic–anaerobic mode with different aeration frequencies by providing air into the upper layer of waste. Results showed that the temporary aeration into the upper layer aided methane generation by shortening the initial acidogenic phase because of volatile fatty acids (VFAs) reduction and pH increase. Chemical oxygen demand (COD) decreased faster in the hybrid bioreactors, but the concentrations of ammonia–nitrogen in the hybrid bioreactors were greater than those in the anaerobic control. Methanogenic conditions were established within 75 d and 60 d in C1 and C2, respectively. However, high aeration frequency led to the consumption of organic matters by aerobic degradation and resulted in reducing accumulative methane volume. The temporary aeration enhanced waste settlement and the settlement increased with increasing the frequency of aeration. Methane production was inhibited in the anaerobic control; however, the total methane generations from hybrid bioreactors were 133.4 L/kg{sub vs} and 113.2 L/kg{sub vs}. As for MSW with high content of food waste, leachate recirculation right after aeration stopped was not recommended due to VFA inhibition for methanogens.

  14. MEASUREMENT OF FUGITIVE EMISSIONS AT A LANDFILL PRACTICING LEACHATE RECIRCULATION AND AIR INJECTION

    EPA Science Inventory

    Recently research has begun on operating bioreactor landfills. The bioreactor process involves the injection of liquid into the waste mass to accelerate waste degradation. Arcadis and EPA conducted a fugitive emissions characterization study at the Three Rivers Solid Waste Techno...

  15. A COMPARISON OF MOLECULAR AND CULTURAL METHODOLOGIES FOR ENUMERATING BACTERIA IN LANDFILL LEACHATES

    EPA Science Inventory

    Landfill bioreactor technology has been under investigation in the field for its potential economic and waste treatment benefits over conventional landfill systems. A better understanding of biological influences on the stabilization process is needed for incorporation into the e...

  16. Effects of ZnO nanoparticle exposure on wastewater treatment and soluble microbial products (SMPs) in an anoxic-aerobic membrane bioreactor.

    PubMed

    Zhang, Dong Qing; Eng, Chin Yee; Stuckey, David C; Zhou, Yan

    2017-03-01

    The effect of zinc oxide nanoparticles (ZnO NPs) on the performance of an anoxic-aerobic submerged membrane bioreactor (MBR), and the characterization of the soluble microbial products (SMPs) produced in the presence of ZnO NPs was evaluated. Continuous operation over 144 days showed that ZnO NPs at concentrations of 10 and 50 mg/L exerted a negative impact on chemical oxygen demand (COD) and nitrogen removal, although ZnO NPs were efficiently removed in the MBR (>92%). 10 and 50 mg/L ZnO NPs decreased COD removal substantially from 93.1± 0.6% to 90.1± 0.8% (<0.05) and 86.3± 2.3% (<0.05), respectively. Similarly, with 10 and 50 mg L ZnO NPs, the decreased in NH4N removal was 8.1% and 21.1%, respectively. Exposure to 1, 10 and 50 mg/L ZnO NPs increased SMP concentrations by 12.8%, 42.4% and 51.5%, respecti. High performance size exclusion chromatograph (HP-SEC) analysis revealed that the presence of ZnO NPs caused a significant increase in high-molecular weight (MW) (583 kDa) SMPs at 1 and 10 mg/L ZnO NP concentration. A substantial decrease in the concentration of high-MW compounds in the MBR effluent was observed at the end of the experiment. Excitation emission matrix (EEM) fluorescence contours revealed that SMPs were dominated by amino acid-, tryptophan protein-, polyaromatic-, and polycarboxylate-type substances. The presence of ZnO NPs enhanced the production of amino acid-like (7.5-25.1%) and tryptophan protein-like compounds (31.7-38.1%), compared to the control (6.0-20.2% for amino acid-like compounds; and 28.5-36.7% for tryptophan protein-like compounds). In contrast, the fulvic and humic acid-like compounds decreased with exposure to ZnO NPs. This work may help better understanding the effect of nanoparticle exposure on wastewater treatment performance and SMP characteristics.

  17. MICROBIAL AND BIOCHEMICAL CHARACTERISTICS OF FRESHLY LANDFILLED WASTE: COMPARISONS TO LANDFILLED WASTES OF DIFFERENT AGES

    EPA Science Inventory

    A cooperative research and development agreement was initiated between U.S. EPA and Waste Management Inc. for a multi-year study of landfill bioreactors at the Outer Loop Landfill in Louisville, KY. As part of the agreement a research project is underway to study the microbiolog...

  18. Degradability of Chlorinated Solvents in Landfill Environment

    NASA Astrophysics Data System (ADS)

    Wang, J. Y.; Litman, M.

    2002-12-01

    The use of landfills as an in situ remediation system represents a cost-effective alternative for groundwater remediation in the source area. This research was conducted to investigate the intrinsic bioattenuation capacity of the landfill ecosystem for chlorinated aliphatic hydrocarbons (CAHs). This research, using excavated refuse samples, studied how the reductive dechlorination of CAHs is linked to the decomposition of solid waste in landfills. Most research effort in groundwater remediation has focused on the contaminant plumes beneath and downgradient from landfills, while the source area remediation has received increasing attention. Bioreactor landfill and leachate recirculation projects have been planned and implemented by the USEPA and some states. However, the use of bioreactor landfill has primarily been considered only to expedite refuse decomposition. This research provides an understanding of the biological fate of CAHs in landfills, an understanding that can lead to the bioreactor landfill system designed to promote the degradation of pollutants right at the source. The research was conducted in two complementary systems: simulated landfill bioreactors and batch degradation experiment in serum bottles. Refuse samples were excavated from a municipal solid waste landfill located in Wayland, Massachusetts, USA. Bioreactors were designed and operated to facilitate refuse decomposition under landfilling conditions. For each reactor, leachate was collected and recirculated back to the reactor and gas was collected into a gas bag and the methane production rate was monitored. Target CAHs, tetrachloroethene (PCE) and trichloroethene (TCE), were added to selected reactors and maintained at about 20 uM each in leachate. The design is to study the effect of long-term exposure of refuse microorganisms to CAHs on the degradation potential of these chemicals in landfills. Changes of biochemical conditions in bioreactors, including leachate pH, leachate COD, and

  19. Leaky Landfills.

    ERIC Educational Resources Information Center

    Jones, Linda L. Cronin

    1992-01-01

    Provides background information on landfills and describes an activity where students learn how a modern landfill is constructed and develop an understanding of the reasons for several regulations regarding modern landfill construction. Students design and construct working models of three types of landfills. (PR)

  20. The influence of hydrolysis induced biopolymers from recycled aerobic sludge on specific methanogenic activity and sludge filterability in an anaerobic membrane bioreactor.

    PubMed

    Buntner, D; Spanjers, H; van Lier, J B

    2014-03-15

    The objective of the present study was to evaluate the impact of excess aerobic sludge on the specific methanogenic activity (SMA), in order to establish the maximum allowable aerobic sludge loading. In batch tests, different ratios of aerobic sludge to anaerobic inoculum were used, i.e. 0.03, 0.05, 0.10 and 0.15, showing that low ratios led to an increased SMA. However, the ratio 0.15 caused more than 20% SMA decrease. In addition to the SMA tests, the potential influence of biopolymers and extracellular substances, that are generated as a result of excess aerobic sludge hydrolysis, on membrane performance was determined by assessing the fouling potential of the liquid broth, taking into account parameters such as specific resistance to filtration (SRF) and supernatant filterability (SF). Addition of aerobic sludge to the anaerobic biomass resulted in a high membrane fouling potential. The increase in biopolymers could be ascribed to aerobic sludge hydrolysis. A clear positive correlation between the concentration of the colloidal fraction of biopolymer clusters (cBPC) and the SRF was observed and a negative correlation between the cBPC and the SF measured at the end of the above described SMA tests. The latter implies that sludge filtration resistance increases when more aerobic sludge is hydrolyzed, and thus more cBPC is released. During AnMBR operation, proteins significantly contributed to sludge filterability decrease expressed as SRF and SF, whereas the carbohydrate fraction of SMP was of less importance due to low concentrations. On the contrary, carbohydrates seemed to improve filterability and diminish SRF of the sludge. Albeit, cBPC increase caused an increase in mean TMP during the AnMBR operation, confirming that cBPC is positively correlated to membrane fouling.

  1. Landfill Methane

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Landfill methane (CH4) accounts for approximately 1.3% (0.6 Gt) of global anthropogenic greenhouse gas emissions relative to total emissions from all sectors of about 49 Gt CO2-eq yr-1. For countries with a history of controlled landfilling, landfills can be one of the larger national sources of ant...

  2. Characteristics and biological treatment of leachates from a domestic landfill

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Waste material from urban areas is a major environmental concern and landfill application is a frequent method for waste disposal. The leachate from landfills can, however, negatively affect the surrounding environment. A bioreactor cascade containing submerged biofilms was used to treat newly forme...

  3. Landfill aeration for emission control before and during landfill mining.

    PubMed

    Raga, Roberto; Cossu, Raffaello; Heerenklage, Joern; Pivato, Alberto; Ritzkowski, Marco

    2015-12-01

    The landfill of Modena, in northern Italy, is now crossed by the new high velocity railway line connecting Milan and Bologna. Waste was completely removed from a part of the landfill and a trench for the train line was built. With the aim of facilitating excavation and further disposal of the material extracted, suitable measures were defined. In order to prevent undesired emissions into the excavation area, the aerobic in situ stabilisation by means of the Airflow technology took place before and during the Landfill Mining. Specific project features involved the pneumatic leachate extraction from the aeration wells (to keep the leachate table low inside the landfill and increase the volume of waste available for air migration) and the controlled moisture addition into a limited zone, for a preliminary evaluation of the effects on process enhancement. Waste and leachate were periodically sampled in the landfill during the aeration before the excavation, for quality assessment over time; the evolution of biogas composition in the landfill body and in the extraction system for different plant set-ups during the project was monitored, with specific focus on uncontrolled migration into the excavation area. Waste biological stability significantly increased during the aeration (waste respiration index dropped to 33% of the initial value after six months). Leachate head decreased from 4 to 1.5m; leachate recirculation tests proved the beneficial effects of moisture addition on temperature control, without hampering waste aerobization. Proper management of the aeration plant enabled the minimization of uncontrolled biogas emissions into the excavation area.

  4. 454-Pyrosequencing analysis of highly adapted azo dye-degrading microbial communities in a two-stage anaerobic-aerobic bioreactor treating textile effluent.

    PubMed

    Köchling, Thorsten; Ferraz, Antônio Djalma Nunes; Florencio, Lourdinha; Kato, Mario Takayuki; Gavazza, Sávia

    2017-03-01

    Azo dyes, which are widely used in the textile industry, exhibit significant toxic characteristics for the environment and the human population. Sequential anaerobic-aerobic reactor systems are efficient for the degradation of dyes and the mineralization of intermediate compounds; however, little is known about the composition of the microbial communities responsible for dye degradation in these systems. 454-Pyrosequencing of the 16S rRNA gene was employed to assess the bacterial biodiversity and composition of a two-stage (anaerobic-aerobic) pilot-scale reactor that treats effluent from a denim factory. The anaerobic reactor was inoculated with anaerobic sludge from a domestic sewage treatment plant. Due to the selective composition of the textile wastewater, after 210 days of operation, the anaerobic reactor was dominated by the single genus Clostridium, affiliated with the Firmicutes phylum. The aerobic biofilter harbored a diverse bacterial community. The most abundant phylum in the aerobic biofilter was Proteobacteria, which was primarily represented by the Gamma, Delta and Epsilon classes followed by Firmicutes and other phyla. Several bacterial genera were identified that most likely played an essential role in azo dye degradation in the investigated system.

  5. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Laptop computer sits atop the Experiment Control Computer for a NASA Bioreactor. The flight crew can change operating conditions in the Bioreactor by using the graphical interface on the laptop. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  6. Intelligent Bioreactor Management Information System (IBM-IS) for Mitigation of Greenhouse Gas Emissions

    SciTech Connect

    Paul Imhoff; Ramin Yazdani; Don Augenstein; Harold Bentley; Pei Chiu

    2010-04-30

    Methane is an important contributor to global warming with a total climate forcing estimated to be close to 20% that of carbon dioxide (CO2) over the past two decades. The largest anthropogenic source of methane in the US is 'conventional' landfills, which account for over 30% of anthropogenic emissions. While controlling greenhouse gas emissions must necessarily focus on large CO2 sources, attention to reducing CH4 emissions from landfills can result in significant reductions in greenhouse gas emissions at low cost. For example, the use of 'controlled' or bioreactor landfilling has been estimated to reduce annual US greenhouse emissions by about 15-30 million tons of CO2 carbon (equivalent) at costs between $3-13/ton carbon. In this project we developed or advanced new management approaches, landfill designs, and landfill operating procedures for bioreactor landfills. These advances are needed to address lingering concerns about bioreactor landfills (e.g., efficient collection of increased CH4 generation) in the waste management industry, concerns that hamper bioreactor implementation and the consequent reductions in CH4 emissions. Collectively, the advances described in this report should result in better control of bioreactor landfills and reductions in CH4 emissions. Several advances are important components of an Intelligent Bioreactor Management Information System (IBM-IS).

  7. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at center) to control fluid flow. A fresh nutrient bag is installed at top; a flattened waste bag behind it will fill as the nutrients are consumed during the course of operation. The drive chain and gears for the rotating wall vessel are visible at bottom center center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  8. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Close-up view of the interior of a NASA Bioreactor shows the plastic plumbing and valves (cylinders at right center) to control fluid flow. The rotating wall vessel is at top center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  9. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Electronics control module for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  10. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Interior of a Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  11. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  12. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Interior view of the gas supply for the NASA Bioreactor. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  13. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Biotechnology Refrigerator that preserves samples for use in (or after culturing in) the NASA Bioreactor. The unit is shown extracted from a middeck locker shell and with thermal blankets partially removed. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  14. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Exterior view of the NASA Bioreactor Engineering Development Unit flown on Mir. The rotating wall vessel is behind the window on the face of the large module. Control electronics are in the module at left; gas supply and cooling fans are in the module at back. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  15. Advanced treatment of landfill leachate using anaerobic-aerobic process: organic removal by simultaneous denitritation and methanogenesis and nitrogen removal via nitrite.

    PubMed

    Sun, Hongwei; Peng, Yongzhen; Shi, Xiaoning

    2015-02-01

    A novel biological system coupling an UASB and a SBR was established to treat landfill leachate. In order to enhance organics and nitrogen removal, simultaneous denitritation and methanogenesis (SDM) was performed in the UASB. Free ammonia (FA) inhibition on nitrite-oxidizing bacteria (NOB) and process control was used to achieve nitrite pathway in the SBR. Results over 623 days showed that the maximum organic removal rate in the UASB and the maximum ammonium oxidization rate in the SBR was 12.7 kgCOD/m(3) d and 0.96 kgN/m(3) d, respectively. The system achieved COD, TN, and NH4(+)-N removal efficiencies of 93.5%, 99.5%, and 99.1%, respectively. By using FA inhibition coupled with process control, the nitrite pathway was started-up in the SBR at low temperatures (14.0-18.2°C) and was maintained for 142 days at temperatures below 15°C (the lowest level was 9.0°C). The predominant ammonia-oxidizing bacteria (AOB) explains essentially stable nitritation obtained.

  16. Rotating Bioreactor

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues currently being cultured in rotating bioreactors by investigators.

  17. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Astronaut John Blaha replaces an exhausted media bag and filled waste bag with fresh bags to continue a bioreactor experiment aboard space station Mir in 1996. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. This image is from a video downlink. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  18. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The heart of the bioreactor is the rotating wall vessel, shown without its support equipment. Volume is about 125 mL. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  19. Bioreactor principles

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Cells cultured on Earth (left) typically settle quickly on the bottom of culture vessels due to gravity. In microgravity (right), cells remain suspended and aggregate to form three-dimensional tissue. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. WASTE STABILIZATION FUNDAMENTALS FOR BIOREACTOR LANDFILLS

    EPA Science Inventory

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

  1. 40 CFR 63.1947 - When do I have to comply with this subpart if I own or operate a bioreactor?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... subpart if I own or operate a bioreactor? 63.1947 Section 63.1947 Protection of Environment ENVIRONMENTAL... or operate a bioreactor? You must comply with this subpart by the dates specified in § 63.1945(a) or (b) of this subpart. If you own or operate a bioreactor located at a landfill that is not...

  2. 40 CFR 63.1947 - When do I have to comply with this subpart if I own or operate a bioreactor?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... subpart if I own or operate a bioreactor? 63.1947 Section 63.1947 Protection of Environment ENVIRONMENTAL... or operate a bioreactor? You must comply with this subpart by the dates specified in § 63.1945(a) or (b) of this subpart. If you own or operate a bioreactor located at a landfill that is not...

  3. 40 CFR 63.1947 - When do I have to comply with this subpart if I own or operate a bioreactor?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... subpart if I own or operate a bioreactor? 63.1947 Section 63.1947 Protection of Environment ENVIRONMENTAL... subpart if I own or operate a bioreactor? You must comply with this subpart by the dates specified in § 63.1945(a) or (b) of this subpart. If you own or operate a bioreactor located at a landfill that is...

  4. 40 CFR 63.1947 - When do I have to comply with this subpart if I own or operate a bioreactor?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... subpart if I own or operate a bioreactor? 63.1947 Section 63.1947 Protection of Environment ENVIRONMENTAL... subpart if I own or operate a bioreactor? You must comply with this subpart by the dates specified in § 63.1945(a) or (b) of this subpart. If you own or operate a bioreactor located at a landfill that is...

  5. 40 CFR 63.1947 - When do I have to comply with this subpart if I own or operate a bioreactor?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... subpart if I own or operate a bioreactor? 63.1947 Section 63.1947 Protection of Environment ENVIRONMENTAL... subpart if I own or operate a bioreactor? You must comply with this subpart by the dates specified in § 63.1945(a) or (b) of this subpart. If you own or operate a bioreactor located at a landfill that is...

  6. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101824 for a version with labels, and No. 0103180 for an operational schematic.

  7. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 degreesC (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  8. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101823 for a version without labels, and No. 0103180 for an operational schematic.

  9. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 deg. C (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  10. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101816 for a version without labels, and No. 0103180 for an operational schematic.

  11. NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101825 for a version with major elements labeled, and No. 0103180 for an operational schematic. 0101816

  12. IN SITU BIOREMEDIATION IN A LANDFILL: LEACHATE CHEMICAL AND MICROBIAL PARAMETERS

    EPA Science Inventory

    In recent years the conversion of landfills to landfill bioreactors has received increased attention owing to potential economic and waste treatment benefits. The U.S. EPA has entered into a Cooperative Research and Development Agreement (CRADA), with Waste Management Inc., testi...

  13. Multimembrane Bioreactor

    NASA Technical Reports Server (NTRS)

    Cho, Toohyon; Shuler, Michael L.

    1989-01-01

    Set of hydrophilic and hydrophobic membranes in bioreactor allows product of reaction to be separated, while nutrients fed to reacting cells and byproducts removed from them. Separation process requires no externally supplied energy; free energy of reaction sufficient. Membranes greatly increase productivity of metabolizing cells by continuously removing product and byproducts, which might otherwise inhibit reaction, and by continuously adding oxygen and organic nutrients.

  14. In situ treatment of landfill leachate using bioventing

    SciTech Connect

    Barr, K.D.; O`Flanagan, B.D.; Newman, W.A.; Julik, J.K.; Wetzstein, D.W.

    1997-01-01

    The effectiveness of in situ, aerobic biodegradation of landfill leachate has been tested by applying bioventing at a closed municipal solid waste landfill in Minnesota. A pilot test was conducted with air injection into a field of six bioventing wells for a six-month period, creating an aerobic biotreatment zone for leachate as it migrates to groundwater. Results show that an effective aerobic treatment zone can be established and maintained with organic compounds actively biodegraded, and dissolved inorganic compounds, such as metals, oxidized and immobilized. Groundwater contaminants also showed decreasing concentrations during the pilot test. This approach may, ultimately, obliterate the need for groundwater removal and treatment.

  15. Migration behavior of Cu and Zn in landfill with different operation modes.

    PubMed

    Long, Yu-Yang; Shen, Dong-Sheng; Wang, Hong-Tao; Lu, Wen-Jing

    2010-07-15

    Cu and Zn were chosen to study the heavy metal migration behavior and mechanism in three simulated landfills with different operation modes, namely conventional landfill (CL), leachate directly recirculated landfill (RL) and leachate pre-treated bioreactor landfill (BL). It showed that Cu and Zn in refuse experienced periodic migration and retention gradually during decomposition, and the variation of Cu(II) and Zn(II) in leachate correspondingly reflected the releasing behavior of Cu and Zn in landfill refuse at different stabilization stages. Except for their accumulated leaching amounts, Cu(II) and Zn(II) concentrations in leachate from landfills with different operation modes had no significant difference. The accumulated leaching amounts of Cu and Zn from CL showed exponential increase, while those of RL and BL showed exponential decay. The operation of bioreactor landfill with leachate recirculation can obviously attenuate the heavy metal leaching than conventional operation. The introduction of methanogenic reactor (MR) in bioreactor landfill can further promote the immobilization of heavy metal in refuse than leachate recirculation directly.

  16. Cleaner Landfills

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Osmotek, Inc. developed the Direct Osmosis treatment system through SBIR funding from Ames Research Center. Using technology originally developed for flight aboard the Space Station, the company brought it to their commercial water purification treatment system, Direct Osmosis. This water purification system uses a direct osmosis process followed by a reverse osmosis treatment. Because the product extracts water from a waste product, Osmotek is marketing the unit for use in landfills. The system can treat leachate (toxic chemicals leached into a water source), by filtering the water and leaving behind the leahcate. The leachate then becomes solidified into substance that can not seep into water.

  17. Tracing landfill gas migration using chlorofluorocarbons

    NASA Astrophysics Data System (ADS)

    Archbold, M.; Elliot, T. E.; Redeker, K.; Boshoff, G.

    2003-04-01

    Typical landfill gas (LFG) compositions include a wide range of trace-level Volatile Organic Compounds (VOCs). The most mobile VOCs are chlorofluorocarbons (CFCs), and their presence around landfills may reflect the initial flushing out of VOCs during the early aerobic stage when landfills are most active reaching high temperatures, driving off VOCs, and injecting LFG into the surrounding environment. CFCs are aerobically stable and therefore, may prove a useful means of characterising the environmental impact of landfill gas in the unsaturated zone around landfills. Moreover, as a possible pathfinder environmental tracer of LFG impacts in the environment, any subsequent changes in the CFCs concentrations after injection potentially reflect natural attenuation (NA) processes, which can also affect other VOCs. Thus tracing the CFCs around a landfill may provide an analogue indicator/proxy for other VOCs transport and fate. To assess the feasibility of using chlorofluorocarbons (CFC-11, CFC-12, CFC-113) as proxy tracers, it is imperative to characterise the effects of possible NA processes on both CFC abundances and their overall systematics. In this research, anaerobic biodegradation microcosm studies, which mimic the unsaturated zone of a LFG plume, are conducted using methanogenic soil samples. Results are discussed in terms of the potential effects on CFCs signatures due to anaerobic biodegradation in the unsaturated zone and will also explore ways of characterising NA processes by identifying the effects of diffusion on transport processes, and degradation products of CFCs. The discussion will also include how stable carbon isotopic signatures may be used to enhance our assessments of biodegradation of CFCs in the unsaturated zone around landfills.

  18. Controls on landfill gas collection efficiency: instantaneous and lifetime performance.

    PubMed

    Barlaz, Morton A; Chanton, Jeff P; Green, Roger B

    2009-12-01

    Estimates of landfill gas (LFG) collection efficiency are required to estimate methane emissions and the environmental performance of a solid waste landfill. The gas collection efficiency varies with time on the basis of the manner in which landfills are designed, operated, and regulated. The literature supports instantaneous collection efficiencies varying between 50% and near 100%, dependent on the cover type and the coverage of the LFG collection system. The authors suggest that the temporally weighted gas collection efficiency, which considers total gas production and collection over the landfill life, is the appropriate way to report collection efficiency. This value was calculated for a range of decay rates representative of refuse buried in arid and wet areas (i.e., >63.5 cm precipitation) and for bioreactor landfills. Temporally weighted collection efficiencies ranging from 67 to 91%, 62 to 86%, and 55 to 78% were calculated at decay rates of 0.02, 0.04, and 0.07 yr(-1), respectively. With aggressive gas collection, as would be implemented for a bioreactor landfill, estimated gas collection efficiency ranged from 84 to 67% at decay rates of 0.04 to 0.15 yr(-1), respectively.

  19. The potential for aeration of MSW landfills to accelerate completion

    SciTech Connect

    Rich, Charlotte; Gronow, Jan; Voulvoulis, Nikolaos

    2008-07-01

    Landfilling is a popular waste disposal method, but, as it is practised currently, it is fundamentally unsustainable. The low short-term financial costs belie the potential long-term environmental costs, and traditional landfill sites require long-term management in order to mitigate any possible environmental damage. Old landfill sites might require aftercare for decades or even centuries, and in some cases remediation may be necessary. Biological stabilisation of a landfill is the key issue; completion criteria provide a yardstick by which the success of any new technology may be measured. In order for a site to achieve completion it must pose no risk to human health or the environment, meaning that attenuation of any emissions from the site must occur within the local environment without causing harm. Remediation of old landfill sites by aerating the waste has been undertaken in Germany, the United States, Italy and The Netherlands, with considerable success. At a pilot scale, aeration has also been used in newly emplaced waste to accelerate stabilisation. This paper reviews the use of aerobic landfill worldwide, and assesses the ways in which the use of aerobic landfill techniques can decrease the risks associated with current landfill practices, making landfill a more sustainable waste disposal option. It focuses on assessing ways to utilise aeration to enhance stabilisation. The results demonstrated that aeration of old landfill sites may be an efficient and cost-effective method of remediation and allow the date of completion to be brought forward by decades. Similarly, aeration of newly emplaced waste can be effective in enhancing degradation, assisting with completion and reducing environmental risks. However, further research is required to establish what procedure for adding air to a landfill would be most suitable for the UK and to investigate new risks that may arise, such as the possible emission of non-methane organic compounds.

  20. Chromium detoxification by fixed-film bioreactors

    SciTech Connect

    Chirwa, E.M.N.; Wang, Y.T.

    1996-11-01

    In this study, completely mixed, continuous flow bioreactors were utilized to detoxify chromium. Glass beads were incorporated as a support medium for two strains of bacteria, Bacillus sp. and Pseudomonas fluorescens LB300 (LB300), growing aerobically in two separate reactors. Aerobic conditions were maintained in the reactors by continuously supplying fresh air to the liquid through gas exchange chambers installed on the recycle line of the bioreactors. Results obtained showed that near complete removal of chromate was possible for influent concentrations up to 200 mg/L for Bacillus sp., and up to 100 mg/L for LB300 at 24 hours liquid detention time. Similar results were obtained for corresponding loading rates at 12 hours and 6 hours liquid detention time.

  1. Bioreactors Addressing Diabetes Mellitus

    PubMed Central

    Minteer, Danielle M.; Gerlach, Jorg C.

    2014-01-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies. PMID:25160666

  2. Bioreactors addressing diabetes mellitus.

    PubMed

    Minteer, Danielle M; Gerlach, Jorg C; Marra, Kacey G

    2014-11-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies.

  3. Diversity and activity of methanotrophs in landfill cover soils with and without landfill gas recovery systems.

    PubMed

    Su, Yao; Zhang, Xuan; Xia, Fang-Fang; Zhang, Qi-Qi; Kong, Jiao-Yan; Wang, Jing; He, Ruo

    2014-05-01

    Aerobic CH4 oxidation plays an important role in mitigating CH4 release from landfills to the atmosphere. Therefore, in this study, oxidation activity and community of methanotrophs were investigated in a subtropical landfill. Among the three sites investigated, the highest CH4 concentration was detected in the landfill cover soil of the site (A) without a landfill gas (LFG) recovery system, although the refuse in the site had been deposited for a longer time (∼14-15 years) compared to the other two sites (∼6-11 years) where a LFG recovery system was applied. In April and September, the higher CH4 flux was detected in site A with 72.4 and 51.7gm(-2)d(-1), respectively, compared to the other sites. The abundance of methanotrophs assessed by quantification of pmoA varied with location and season. A linear relationship was observed between the abundance of methanotrophs and CH4 concentrations in the landfill cover soils (R=0.827, P<0.001). The key factors influencing the methanotrophic diversity in the landfill cover soils were pH, the water content and the CH4 concentration in the soil, of which pH was the most important factor. Type I methanotrophs, including Methylococcus, Methylosarcina, Methylomicrobium and Methylobacter, and type II methanotrophs (Methylocystis) were all detected in the landfill cover soils, with Methylocystis and Methylosarcina being the dominant genera. Methylocystis was abundant in the slightly acidic landfill cover soil, especially in September, and represented more than 89% of the total terminal-restriction fragment abundance. These findings indicated that the LFG recovery system, as well as physical and chemical parameters, affected the diversity and activity of methanotrophs in landfill cover soils.

  4. Perpetual landfilling through aeration of the waste mass; lessons from test cells in Georgia (USA).

    PubMed

    Read, A D; Hudgins, M; Phillips, P

    2001-01-01

    Municipal solid waste (MSW) landfills worldwide are experiencing the consequences of conventional landfilling techniques, whereby anaerobic conditions are created within the landfilled waste. Under anaerobic conditions within a landfill site slow stabilization of the waste mass occurs, producing methane, (an explosive 'green house' gas) and leachate (which can pollute groundwater) over long periods of time. As a potential solution, it was demonstrated that the aerobic degradation of MSW within a landfill can significantly increase the rate of waste decomposition and settlement, decrease the methane production and leachate leaving the system, and potentially increase the operational life of the site. Readily integrated into the existing landfill infrastructure, this approach can safely and cost-effectively convert a MSW landfill from anaerobic to aerobic degradation processes, thereby effectively composting much of the organic portions (one of the potentially polluting elements in a conventional landfill site) of the waste. This paper summarizes the successful results of two separate aerobic landfill projects located in Georgia (USA) and discusses the potential economic and environmental impacts to worldwide solid waste management practices.

  5. Landfill Gas Energy

    EPA Pesticide Factsheets

    This guide describes how local governments and communities can achieve energy, environmental, health, and economic benefits by using landfill gas (LFG) recovered from municipal solid waste landfills as a source of renewable energy.

  6. Learning from Landfills.

    ERIC Educational Resources Information Center

    Galus, Pamela

    2000-01-01

    Describes a project in which students developed an all-class laboratory activity called "The Decomposition of Organic and Inorganic Substances in a Landfill". Explores what conditions are necessary to facilitate decomposition in a landfill. (SAH)

  7. [Nitrous oxide emissions from municipal solid waste landfills and its measuring methodology: a review].

    PubMed

    Jia, Ming-Sheng; Wang, Xiao-Jun; Chen, Shao-Hua

    2014-06-01

    Nitrous oxide (N2O) is one of three major greenhouse gases and the dominant ozone-depleting substance. Landfilling is the major approach for the treatment and disposal of municipal solid waste (MSW), while MSW landfills can be an important anthropogenic source for N2O emissions. Measurements at lab-scale and full-scale landfills have demonstrated that N2O can be emitted in substantial amounts in MSW landfills; however, a large variation in reported emission values exists. Currently, the mechanisms of N2O production and emission in landfills and its contribution to global warming are still lack of sufficient studies. Meanwhile, obtaining reliable N2O fluxes data in landfills remains a question with existing in-situ measurement techniques. This paper summarized relevant literature data on this issue and analyzed the potential production and emission mechanisms of N2O in traditional anaerobic sanitary landfill by dividing it into the MSW buried and the cover soil. The corresponding mechanisms in nitrogen removal bioreactor landfills were analyzed. Finally, the applicability of existing in-situ approaches measuring N2O fluxes in landfills, such as chamber and micrometeorological methods, was discussed and areas in which further research concerning N2O emissions in landfills was urgently required were proposed as well.

  8. In-situ treatment of landfill leachate and wastes using bioventing technology

    SciTech Connect

    Barr, K.D.; O`Flanagan, B.D.; Newman, W.A.

    1995-12-31

    The effectiveness of in-situ, aerobic biodegradation of landfill leachate has been tested by applying bioventing at a closed municipal solid waste landfill in Minnesota. A pilot test was conducted with air injection into a field of six bioventing wells for a six month period, creating an aerobic biotreatment zone for leachate as it migrates to groundwater. Results show that an effective aerobic treatment zone can be established and maintained with organic compounds actively biodegraded and dissolved inorganic compounds, such as metals, oxidized and immobilized. Groundwater contaminants also showed decreasing concentrations during the pilot test. This approach may, ultimately, obviate the need for groundwater removal and treatment.

  9. In-situ treatment of landfill leachate and wastes using bioventing technology

    SciTech Connect

    Barr, K.D.; O`Flanagan, B.D.; Newman, W.A.; Julik, J.K.; Wetzstein, D.W.

    1995-12-31

    The effectiveness of in-situ, aerobic biodegradation of landfill leachate has been tested by applying bioventing at a closed municipal solid waste landfill in Minnesota. A pilot test was conducted with air injection into a field of six bioventing wells for a six month period, creating an aerobic biotreatment zone for leachate as it migrates to ground water. Results show that an effective aerobic treatment zone can be established and maintained with organic compounds actively biodegraded and dissolved inorganic compounds, such as metals, oxidized and immobilized. Groundwater contaminants also showed decreasing concentrations during the pilot test. This approach may, ultimately, obviate the need for groundwater removal and treatment.

  10. Dynamic global sensitivity analysis in bioreactor networks for bioethanol production.

    PubMed

    Ochoa, M P; Estrada, V; Di Maggio, J; Hoch, P M

    2016-01-01

    Dynamic global sensitivity analysis (GSA) was performed for three different dynamic bioreactor models of increasing complexity: a fermenter for bioethanol production, a bioreactors network, where two types of bioreactors were considered: aerobic for biomass production and anaerobic for bioethanol production and a co-fermenter bioreactor, to identify the parameters that most contribute to uncertainty in model outputs. Sobol's method was used to calculate time profiles for sensitivity indices. Numerical results have shown the time-variant influence of uncertain parameters on model variables. Most influential model parameters have been determined. For the model of the bioethanol fermenter, μmax (maximum growth rate) and Ks (half-saturation constant) are the parameters with largest contribution to model variables uncertainty; in the bioreactors network, the most influential parameter is μmax,1 (maximum growth rate in bioreactor 1); whereas λ (glucose-to-total sugars concentration ratio in the feed) is the most influential parameter over all model variables in the co-fermentation bioreactor.

  11. Landfill disposal systems

    PubMed Central

    Slimak, Karen M.

    1978-01-01

    The current status of landfill disposal of hazardous wastes in the United States is indicated by presenting descriptions of six operating landfills. These landfills illustrate the variety of techniques that exist in landfill disposal of hazardous wastes. Although some landfills more effectively isolate hazardous waste than others, all landfills must deal with the following problems. Leachate from hazardous waste landfills is generally highly polluted. Most landfills attempt to contain leachate at the site and prevent its discharge to surface or groundwaters. To retain leachate within a disposal area, subsurface barriers of materials such as concrete, asphalt, butyl rubber, vinyl, and clay are used. It is difficult to assure that these materials can seal a landfill indefinitely. When a subsurface barrier fails, the leachate enters the groundwater in a concentrated, narrow band which may bypass monitoring wells. Once a subsurface barrier has failed, repairs are time-consuming and costly, since the waste above the repair site may have to be removed. The central problem in landfill disposal is leachate control. Recent emphasis has been on developing subsurface barriers to contain the wastes and any leachate. Future emphasis should also be on techniques for removing water from hazardous wastes before they are placed in landfills, and on methods for preventing contact of the wastes with water during and after disposal operations. When leachate is eliminated, the problems of monitoring, and subsurface barrier failure and repair can be addressed, and a waste can be effectively isolated. A surface seal landfill design is recommended for maintaining the dry state of solid hazardous wastes and for controlling leachate. Any impervious liner is utilized over the top of the landfill to prevent surface water from seeping into the waste. The surface barrier is also the site where monitoring and maintenance activities are focused. Barrier failure can be detected by visual

  12. Minimizing N2O fluxes from full-scale municipal solid waste landfill with properly selected cover soil.

    PubMed

    Zhang, Houhu; He, Pinjing; Shao, Liming; Qu, Xian; Lee, Duujong

    2008-01-01

    Municipal solid waste landfills emit nitrous oxide (N2O) gas. Assuming that the soil cover is the primary N2O source from landfills, this study tested, during a four-year project, the hypothesis that the proper use of chosen soils with fine texture minimizes N2O emissions. A full-scale sanitary landfill, a full-scale bioreactor landfill and a cell planted with Nerium indicum or Festuca arundinacea Schreb, at the Hangzhou Tianziling landfill in Hangzhou City were the test sites. The N2O emission rates from all test sites were considerably lower than those reported in the published reports. Specifically, the N2O emission rate was dependent on soil water content and nitrate concentrations in the cover soil. The effects of leachate recirculation and irrigation were minimal. Properly chosen cover soils applied to the landfills reduced N2O flux.

  13. NASA Bioreactor Demonstration System

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  14. Aerobic Tennis.

    ERIC Educational Resources Information Center

    Stewart, Michael J.; Ahlschwede, Robert

    1989-01-01

    Increasing the aerobic nature of tennis drills in the physical education class may be necessary if tennis is to remain a part of the public school curriculum. This article gives two examples of drills that can be modified by teachers to increase activity level. (IAH)

  15. Mining landfills for recyclables

    SciTech Connect

    Spencer, R.

    1991-02-01

    The New York State Energy Research and Development Authority (NYSERDA) and the Department of Environmental Conservation (DEC) began a landfill reclamation experiment in Edinburgh, NY, a rural community in the Adirondack Park. According to NYSERDA's Fact Sheet about the project, landfill reclamation is a process of excavating a landfill using conventional surface mining technology to recover metals, glass, plastics and combustibles, soils, and the land resource itself. The recovered site can then be either upgraded into a state-of-the-art landfill, if appropriate, closed or redeveloped for some other suitable purpose. As an energy-related public benefit corporation, NYSERDA is particularly interested in the potential energy value of combustible material reclaimed from landfills. With an energy content of over 11 million BTUs per ton, this translates to the energy equivalent of 275 million barrels of oil.

  16. The impact of landfilling and composting on greenhouse gas emissions--a review.

    PubMed

    Lou, X F; Nair, J

    2009-08-01

    Municipal solid waste is a significant contributor to greenhouse gas emissions through decomposition and life-cycle activities processes. The majority of these emissions are a result of landfilling, which remains the primary waste disposal strategy internationally. As a result, countries have been incorporating alternative forms of waste management strategies such as energy recovery from landfill gas capture, aerobic landfilling (aerox landfills), pre-composting of waste prior to landfilling, landfill capping and composting of the organic fraction of municipal solid waste. As the changing global climate has been one of the major environmental challenges facing the world today, there is an increasing need to understand the impact of waste management on greenhouse gas emissions. This review paper serves to provide an overview on the impact of landfilling (and its various alternatives) and composting on greenhouse gas emissions taking into account streamlined life cycle activities and the decomposition process. The review suggests greenhouse gas emissions from waste decomposition are considerably higher for landfills than composting. However, mixed results were found for greenhouse gas emissions for landfill and composting operational activities. Nonetheless, in general, net greenhouse gas emissions for landfills tend to be higher than that for composting facilities.

  17. A Coupling Kinetics Model for Pollutant Release and Transport in the Process of Landfill Settlement

    PubMed Central

    Zhao, Ying; Xue, Qiang; Liu, Lei

    2012-01-01

    A coupling kinetics model is developed to simulate the release and transport of landfill leachate pollutants in a deformable municipal solid waste landfill by taking into account of landfill settlement, seepage of leachate water, hydrolyse of insoluble and degradable organic pollutants in solid phase, biodegradation of soluble and degradable organic pollutants in solid phase and aqueous one, growth of aerobic and anaerobic microorganism, and consumption of dissolved oxygen. The release and transport of organic pollutants and microorganisms in landfills in the process of landfill settlement was simulated by considering no hydraulic effect. Simulation results demonstrated that the interaction between landfill settlement and the release, transport and biodegradation of landfill leachate pollutants was significant. Porosity and saturated hydraulic conductivity were not constants because of the landfill settlement, which affected the release, transport and biodegradation of landfill leachate pollutants, and furthermore acted on the landfill settlement. The simulation results accorded with the practical situation, which preliminarily verified the reliability of the mathematical model and the numerical program in this paper. PMID:23202755

  18. A coupling kinetics model for pollutant release and transport in the process of landfill settlement.

    PubMed

    Zhao, Ying; Xue, Qiang; Liu, Lei

    2012-09-27

    A coupling kinetics model is developed to simulate the release and transport of landfill leachate pollutants in a deformable municipal solid waste landfill by taking into account of landfill settlement, seepage of leachate water, hydrolyse of insoluble and degradable organic pollutants in solid phase, biodegradation of soluble and degradable organic pollutants in solid phase and aqueous one, growth of aerobic and anaerobic microorganism, and consumption of dissolved oxygen. The release and transport of organic pollutants and microorganisms in landfills in the process of landfill settlement was simulated by considering no hydraulic effect. Simulation results demonstrated that the interaction between landfill settlement and the release, transport and biodegradation of landfill leachate pollutants was significant. Porosity and saturated hydraulic conductivity were not constants because of the landfill settlement, which affected the release, transport and biodegradation of landfill leachate pollutants, and furthermore acted on the landfill settlement. The simulation results accorded with the practical situation, which preliminarily verified the reliability of the mathematical model and the numerical program in this paper.

  19. Evaluation of Partitioning Gas Tracer Tests for Measuring Water in Landfills

    NASA Astrophysics Data System (ADS)

    Imhoff, P. T.; Han, B.; Jafarpour, Y.; Gallagher, V. N.; Chiu, P. C.; Fluman, D. A.; Vasuki, N. C.; Yazdani, R.; Augenstein, D.; Cohen, K. K.

    2003-12-01

    Methane is an important greenhouse gas, and landfills are the largest anthropogenic source in many developed countries. Bioreactor landfills have been proposed as one means of abating greenhouse gas emissions from landfills. Here, the decomposition of organic wastes is enhanced by the controlled addition of water or leachate to maintain optimal conditions for waste decomposition. Greenhouse gas abatement is accomplished by sequestration of photosynthetically derived carbon in wastes, CO2 offsets from energy use of waste derived gas, and mitigation of methane emission from the wastes. An important issue in the operation of bioreactor landfills is knowing how much water to add and where to add it. Accurate methods for measuring the amount of water in landfills would be valuable aids for implementing leachate recirculation systems. Current methods for measuring water are inadequate, though, since they provide point measurements and are frequently affected by heterogeneity of the solid waste composition and solid waste compaction. The value of point measurements is significantly reduced in systems where water flows preferentially, such as in landfills. Here, spatially integrated measurements might be of greater value. We are evaluating a promising technology, the partitioning gas tracer test, to measure the water saturation within landfills, the amount of free water in solid waste divided by the volume of the voids. The partitioning gas tracer test was recently developed by researchers working in the vadose zone. We report the results from laboratory and field tests designed to evaluate the partitioning gas tracer test within an anaerobic landfill operated by the Delaware Solid Waste Authority. Vertical wells were installed within the landfill to inject and extract tracer gases. Gas flow and tracer gas movement in the solid waste were controlled by the landfill's existing gas collection system, which included vertical wells installed throughout the landfill through

  20. Bioreactor rotating wall vessel

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  1. Bio-tarp alternative daily cover prototypes for methane oxidation atop open landfill cells.

    PubMed

    Adams, Bryn L; Besnard, Fabien; Bogner, Jean; Hilger, Helene

    2011-05-01

    Final landfill covers are highly engineered to prevent methane release into the atmosphere. However, methane production begins soon after waste placement and is an unaddressed source of emissions. The methane oxidation capacity of methanotrophs embedded in a "bio-tarp" was investigated as a means to mitigate methane release from open landfill cells. The bio-tarp would also serve as an alternative daily cover during routine landfill operation. Evaluations of nine synthetic geotextiles identified two that would likely be suitable bio-tarp components. Pilot tarp prototypes were tested in continuous flow systems simulating landfill gas conditions. Multilayered bio-tarp prototypes consisting of alternating layers of the two geotextiles were found to remove 16% of the methane flowing through the bio-tarp. The addition of landfill cover soil, compost, or shale amendments to the bio-tarp increased the methane removal up to 32%. With evidence of methane removal in a laboratory bioreactor, prototypes were evaluated at a local landfill using flux chambers installed atop intermediate cover at a landfill. The multilayered bio-tarp and amended bio-tarp configurations were all found to decrease landfill methane flux; however, the performance efficacy of bio-tarps was not significantly different from controls without methanotrophs. Because highly variable methane fluxes at the field site likely confounded the test results, repeat field testing is recommended under more controlled flux conditions.

  2. Evaluation of Biodegradability of Waste Before and After Aerobic Treatment

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  3. Bioreactors and fermentation. June 1978-January 1990 (A Bibliography from the Life Sciences Collection data base). Report for June 1978-January 1990

    SciTech Connect

    Not Available

    1990-04-01

    This bibliography contains citations concerning the use of bioreactors in fermentation processes. References cover aerobic and anaerobic technologies involving yeasts, microorganisms, and enzymes as bioreactors. These technologies are useful in the production of ethanol, methanol (methane), butanol, organic acids, protein enhancers, and nitrogen enhancers in the dairy, agricultural, food, beverage processing, and medical industries. (Contains 206 citations fully indexed and including a title list.)

  4. 40 CFR 258.41 - Project XL Bioreactor Landfill Projects.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ions; (J) Heavy metals; (K) Organic priority pollutants; and (L) Flow rate; (viii) Quantity of leachate... (ammonia, total kjeldahl nitrogen, total phosphorus), Common Ions, Heavy Metals and Organic...

  5. 40 CFR 258.41 - Project XL Bioreactor Landfill Projects.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ions; (J) Heavy metals; (K) Organic priority pollutants; and (L) Flow rate; (viii) Quantity of leachate... (ammonia, total kjeldahl nitrogen, total phosphorus), Common Ions, Heavy Metals and Organic...

  6. Bondad Landfill NPDES Permit

    EPA Pesticide Factsheets

    Under National Pollutant Discharge Elimination System permit number CO-R050005, Transit Waste, LLC is authorized to discharge from the Bondad Landfill facility in La Plata County, Colorado, to an unnamed tributary of the Animas River.

  7. Lancaster Landfill Solar Facility

    SciTech Connect

    Pacheco, Orlando

    2014-06-12

    The Town of Lancaster constructed a 500KWH Solar Array on our landfill parcel, that using other financial mechanisms in the deregulated Massachusetts Electric Market would allow the Town to obtain free electricity.

  8. Tapered bed bioreactor

    DOEpatents

    Scott, Charles D.; Hancher, Charles W.

    1977-01-01

    A vertically oriented conically shaped column is used as a fluidized bed bioreactor wherein biologically catalyzed reactions are conducted in a continuous manner. The column utilizes a packing material a support having attached thereto a biologically active catalytic material.

  9. Space Bioreactor Science Workshop

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Editor)

    1987-01-01

    The first space bioreactor has been designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and a slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small (500 ml) bioreactor is being constructed for flight experiments in the Shuttle middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption, and control of low shear stress on cells. Applications of microcarrier cultures, development of the first space bioreactor flight system, shear and mixing effects on cells, process control, and methods to monitor cell metabolism and nutrient requirements are among the topics covered.

  10. Bioreactor design concepts

    NASA Technical Reports Server (NTRS)

    Bowie, William

    1987-01-01

    Two parallel lines of work are underway in the bioreactor laboratory. One of the efforts is devoted to the continued development and utilization of a laboratory research system. That system's design is intended to be fluid and dynamic. The sole purpose of such a device is to allow testing and development of equipment concepts and procedures. Some of the results of those processes are discussed. A second effort is designed to produce a flight-like bioreactor contained in a double middeck locker. The result of that effort has been to freeze a particular bioreactor design in order to allow fabrication of the custom parts. The system is expected to be ready for flight in early 1988. However, continued use of the laboratory system will lead to improvements in the space bioreactor. Those improvements can only be integrated after the initial flight series.

  11. Water balance comparison between a dry and a wet landfill — a full-scale experiment

    NASA Astrophysics Data System (ADS)

    Yuen, S. T. S.; Wang, Q. J.; Styles, J. R.; McMahon, T. A.

    2001-09-01

    This paper describes a water balance study conducted in a full-scale experimental municipal solid waste landfill in Melbourne, Australia. The investigation identified the significance of various hydrological components of a 'dry' landfill (represented by half of the experimental cell as a control section) and a 'wet' landfill (represented by other half of the cell allowing leachate recirculation and working as a bioreactor). The information obtained is important and useful in terms of leachate management for both dry and wet cell operations, especially for landfills located in a similar climate region. The study also determined the in situ field capacity of the waste and compared it to published data. The implication of using this field capacity value in water balance study is discussed.

  12. The Outer Loop bioreactor: a case study of settlement monitoring and solids decomposition.

    PubMed

    Abichou, Tarek; Barlaz, Morton A; Green, Roger; Hater, Gary

    2013-10-01

    The Outer Loop landfill bioreactor (OLLB) located in Louisville, KY, USA has been in operation since 2000 and represents an opportunity to evaluate long-term bioreactor monitoring data at a full-scale operational landfill. Three types of landfill units were studied including a Control cell, a new landfill area that had a piping network installed as waste was being placed to support leachate recirculation (As-Built cell), and a conventional landfill that was modified to allow for liquid recirculation (Retrofit cell). The objective of this study is to summarize the results of settlement data and assess how these data relate to solids decomposition monitoring at the OLLB. The Retrofit cells started to settle as soon as liquids were introduced. The cumulative settlement during the 8years of monitoring varied from 60 to 100cm. These results suggest that liquid recirculation in the Retrofit cells caused a 5-8% reduction in the thickness of the waste column. The average long-term settlement in the As-Built and Control Cells was about 37% and 19%, respectively. The modified compression index (Cα(')) was 0.17 for the Control cells and 0.2-0.48 for the As-Built cells. While the As-Built cells exhibited greater settlement than the Control cells, the data do not support biodegradation as the only explanation. The increased settlement in the As-Built bioreactor cell appeared to be associated with liquid movement and not with biodegradation because both chemical (biochemical methane potential) and physical (moisture content) indicators of decomposition were similar in the Control and As-Built cells. The solids data are consistent with the concept that bioreactor operations accelerate the rate of decomposition, but not necessarily the cumulative loss of anaerobically degradable solids.

  13. Leachate recirculation between alternating aged refuse bioreactors and its effect on refuse decomposition.

    PubMed

    Sun, Xiaojie; Sun, Yingjie; Zhao, Youcai; Wang, Ya-Nan

    2014-01-01

    In a sequencing batch bioreactor landfill system which combined a fresh and an aged refuse bioreactor, blockage occurred frequently in the aged refuse bioreactor during the treatment of leachate from the fresh refuse bioreactor. To overcome this problem, another aged refuse bioreactor was added, when blockage occurred, the two aged refuse bioreactor operated alternatively. A fresh refuse bioreactor F combined with two alternating aged refuse bioreactors A1 and A2 was called alternate recirculation process (ARP) in this study. The bioreactor system was operated in three stages, and the three bioreactors were exposed to air to facilitate surface re-aeration. The effect of the ARP on the accelerated degradation of fresh refuse was compared before and after blockage occurs in A1. The results indicated that ARP can improve the leachate production rate. The average daily net production rates of leachate in Stages 2 and 3 were approximately 2.1 and 1.6 mL (kgrefuse d)(-1), respectively, which exceeded that of Stage 1 (1.3 mL (kg refuse d)(-1)). The chemical oxygen demand and NH3-N concentrations of the leachate from Stage 1 are 1000 and 25mgL(-1) after 2.1 and 2.7 y, respectively. For Stages 2 and 3, these concentrations reach approximately after 0.877 and 1.3 y. Faster refuse settlement was observed in Stages 2 and 3, with an average daily settlement of approximately 0.11%, as compared with Stage 1 (approximately 0.099%). ARP can accelerate the biodegradation of the fresh refuse and overcome the problem of the blockage in the aged refuse reactor.

  14. Numerical simulation of landfill gas pressure distribution in landfills.

    PubMed

    Xi, Yonghui; Xiong, Hao

    2013-11-01

    Landfill gas emissions are recognized as one of the three major concerns in municipal solid waste landfills. There are many factors that affect the generation of landfill gas when the landfill is capped. In this article, a model has been developed based on the theory of porous media flow. The model could predict the pressure distribution of landfill gas in landfill, coupling the effect of landfill settlement. According to the simulation analysis of landfill, it was found that: (a) the landfill gas pressure would reach a peak after 1.5 years, then begin to decline, and the rate of decay would slow down after 10 years; (b) the influence radius of the gas wells is limited; (c) the peak value of landfill gas pressure is larger, it appears later and the rate of decay is slower when the landfill settlement is considered in the model; (d) the calculation of excess gas pressure in landfill under different negative pressures of the extraction well is compared between this model and another model, and the results show that the relative pressure distribution form and range are almost the same.

  15. Effect of nano-ZnO on biogas generation from simulated landfills.

    PubMed

    Temizel, İlknur; Emadian, S Mehdi; Di Addario, Martina; Onay, Turgut T; Demirel, Burak; Copty, Nadim K; Karanfil, Tanju

    2017-01-23

    Extensive use of nanomaterials in commercial consumer products and industrial applications eventually leads to their release to the waste streams and the environment. Nano-ZnO is one of the most widely-used nanomaterials (NMs) due to its unique properties. It is also known to impact biological processes adversely. In this study, the effect of nano-ZnO on biogas generation from sanitary landfills was investigated. Two conventional and two bioreactor landfills were operated using real MSW samples at mesophilic temperature (35°C) for a period of about 1year. 100mg nano-ZnO/kg of dry waste was added to the simulated landfill reactors. Daily gas production, gas composition and leachate Zn concentrations were regularly monitored. A model describing the fate of the nano-ZnO was also developed. The results obtained indicated that as much as 99% of the nano-ZnO was retained within the waste matrix for both reactor operation modes. Waste stabilization was faster in simulated landfill bioreactors with and without the addition of nano-ZnO. Moreover, the presence of the nano-ZnO within the waste led to a decrease in biogas production of about 15%, suggesting that the nano-ZnO might have some inhibitory effects on waste stabilization. This reduction can have potentially significant implications on waste stabilization and the use of biogas from landfills as a renewable energy source.

  16. Municipal landfill leachate management

    SciTech Connect

    Kusterer, T.; Willson, R.; Bruce, S.C.; Tissue, E. Lou, P.J.

    1998-12-31

    From 1995 to 1997, the Montgomery County Leachate Pretreatment Facility (MCLPF) has successfully pretreated in excess of 18,000,000 gallons of leachate generated by the county`s municipal solid waste landfill. The collection system directs leachate from the original landfill. The collection system directs leachate from the original landfill, the new lined section, and the ash cell to the leachate pump station. The leachate, prior to being pumped to the leachate pretreatment system, is equalized in two storage lagoons with a combined capacity of more than 5,000,000 gallons. The innovative leachate treatment system, incorporating a biological reactor system equipped with a submerged fixed-film reactor using a patented Matrix Biological Film (MBF) media, continues to provide excellent pretreatment results for the leachate generated at the Oaks Landfill in Montgomery County, Maryland. In 1995 and 1996, the system responded to the substantial challenges imposed by the changing characteristics of the material being landfilled and by the significant amounts of incinerator ash, received in 1995 from the county`s resource recovery facility (RRF), which influenced the influent leachate characteristics.

  17. NASA Bioreactor Schematic

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The schematic depicts the major elements and flow patterns inside the NASA Bioreactor system. Waste and fresh medium are contained in plastic bags placed side-by-side so the waste bag fills as the fresh medium bag is depleted. The compliance vessel contains a bladder to accommodate pressure transients that might damage the system. A peristolic pump moves fluid by squeezing the plastic tubing, thus avoiding potential contamination. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  18. NASA Classroom Bioreactor

    NASA Technical Reports Server (NTRS)

    Scully, Robert

    2004-01-01

    Exploration of space provides a compelling need for cell-based research into the basic mechanisms that underlie the profound changes that occur in terrestrial life that is transitioned to low gravity environments. Toward that end, NASA developed a rotating bioreactor in which cells are cultured while continuously suspended in a cylinder in which the culture medium rotates with the cylinder. The randomization of the gravity vector accomplished by the continuous rotation, in a low shear environment, provides an analog of microgravity. Because cultures grown in bioreactors develop structures and functions that are much closer to those exhibited by native tissue than can be achieved with traditional culture methods, bioreactors have contributed substantially to advancing research in the fields of cancer, diabetes, infectious disease modeling for vaccine production, drug efficacy, and tissue engineering. NASA has developed a Classroom Bioreactor (CB) that is built from parts that are easily obtained and assembled, user-friendly and versatile. It can be easily used in simple school settings to examine the effect cultures of seeds or cells. An educational brief provides assembly instructions and lesson plans that describes activities in science, math and technology that explore free fall, microgravity, orbits, bioreactors, structure-function relationships and the scientific method.

  19. Baghdad Municipal Solid Waste Landfill

    DTIC Science & Technology

    2006-10-19

    SOLID WASTE LANDFILL SIGIR PA... Solid Waste Landfill 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT...Municipal Solid Waste Landfill , Baghdad, Iraq (Report Number SIGIR-PA-06-067) We are providing this project assessment report for your information

  20. Stable isotope signatures for characterising the biological stability of landfilled municipal solid waste

    SciTech Connect

    Wimmer, Bernhard; Hrad, Marlies; Huber-Humer, Marion; Watzinger, Andrea; Wyhlidal, Stefan; Reichenauer, Thomas G.

    2013-10-15

    Highlights: ► The isotopic signature of δ{sup 13}C-DIC of leachates is linked to the reactivity of MSW. ► Isotopic signatures of leachates depend on aerobic/anaerobic conditions in landfills. ► In situ aeration of landfills can be monitored by isotope analysis in leachate. ► The isotopic analysis of leachates can be used for assessing the stability of MSW. ► δ{sup 13}C-DIC of leachates helps to define the duration of landfill aftercare. - Abstract: Stable isotopic signatures of landfill leachates are influenced by processes within municipal solid waste (MSW) landfills mainly depending on the aerobic/anaerobic phase of the landfill. We investigated the isotopic signatures of δ{sup 13}C, δ{sup 2}H and δ{sup 18}O of different leachates from lab-scale experiments, lysimeter experiments and a landfill under in situ aeration. In the laboratory, columns filled with MSW of different age and reactivity were percolated under aerobic and anaerobic conditions. In landfill simulation reactors, waste of a 25 year old landfill was kept under aerobic and anaerobic conditions. The lysimeter facility was filled with mechanically shredded fresh waste. After starting of the methane production the waste in the lysimeter containments was aerated in situ. Leachate and gas composition were monitored continuously. In addition the seepage water of an old landfill was collected and analysed periodically before and during an in situ aeration. We found significant differences in the δ{sup 13}C-value of the dissolved inorganic carbon (δ{sup 13}C-DIC) of the leachate between aerobic and anaerobic waste material. During aerobic degradation, the signature of δ{sup 13}C-DIC was mainly dependent on the isotopic composition of the organic matter in the waste, resulting in a δ{sup 13}C-DIC of −20‰ to −25‰. The production of methane under anaerobic conditions caused an increase in δ{sup 13}C-DIC up to values of +10‰ and higher depending on the actual reactivity of the MSW

  1. Bioreactors and fermentation. (Latest citations from the Life Sciences Collection database). Published Search

    SciTech Connect

    Not Available

    1994-02-01

    The bibliography contains citations concerning the use of bioreactors in fermentation processes. Topics include aerobic and anaerobic technologies involving yeasts, microorganisms, and enzymes. These technologies are useful in the production of ethanol, methanol (methane), butanol, organic acids, protein enhancers, and nitrogen enhancers in the dairy, agricultural, food, beverage processing, and medical industries. (Contains 250 citations and includes a subject term index and title list.)

  2. Potential application of a bioreactor for removing nitrate from nursery runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A bacterial-based bioreactor containing Kaldness media as a substrate for bacteria to grow on was established at a commercial nursery. During the media loading stage, redox potential was poised between +100 and +300 mv, indicating relatively aerobic conditions. Redox potential was highly variabl...

  3. MTBE BIODEGRADATION IN A GRAVITY FLOW, HIGH-BIOMASS RETAINING BIOREACTOR

    EPA Science Inventory

    The aerobic biodegradation of methyl tert-butyl ether (MtBE), a widely used fuel oxygenate, was investigated using a pilot-scale biomass-retaining bioreactor called a Biomass Concentrator Reactor (BCR). The reactor was operated for a year at a flow rate of 2500 L/d on Ci...

  4. Landfill aeration in the framework of a reclamation project in Northern Italy.

    PubMed

    Raga, Roberto; Cossu, Raffaello

    2014-03-01

    In situ aeration by means of the Airflow technology was proposed for landfill conditioning before landfill mining in the framework of a reclamation project in Northern Italy. A 1-year aeration project was carried out on part of the landfill with the objective of evaluating the effectiveness of the Airflow technology for landfill aerobization, the evolution of waste biological stability during aeration and the effects on leachate and biogas quality and emissions. The main outcomes of the 1-year aeration project are presented in the paper. The beneficial effect of the aeration on waste biological stability was clear (63% reduction of the respiration index); however, the effectiveness of aeration on the lower part of the landfill is questionable, due to the limited potential for air migration into the leachate saturated layers. During the 1-year in situ aeration project approx. 275 MgC were discharged from the landfill body with the extracted gas, corresponding to 4.6 gC/kgDM. However, due to the presence of anaerobic niches in the aerated landfill, approx. 46% of this amount was extracted as CH4, which is higher than reported in other aeration projects. The O2 conversion quota was lower than reported in other similar projects, mainly due to the higher air flow rates applied. The results obtained enabled valuable recommendations to be made for the subsequent application of the Airflow technology to the whole landfill.

  5. Energy potential of modern landfills

    SciTech Connect

    Bogner, J.E.

    1990-01-01

    Methane produced by refuse decomposition in a sanitary landfill can be recovered for commercial use. Landfill methane is currently under-utilized, with commercial recovery at only a small percentage of US landfills. New federal regulations mandating control of landfill gas migration and atmospheric emissions are providing impetus to methane recovery schemes as a means of recovering costs for increased environmental control. The benefits of landfill methane recovery include utilization of an inexpensive renewable energy resource, removal of explosive gas mixtures from the subsurface, and mitigation of observed historic increases in atmospheric methane. Increased commercial interest in landfill methane recovery is dependent on the final form of Clean Air Act amendments pertaining to gaseous emissions from landfills; market shifts in natural gas prices; financial incentives for development of renewable energy resources; and support for applied research and development to develop techniques for increased control of the gas generation process in situ. This paper will discuss the controls on methane generation in landfills. In addition, it will address how landfill regulations affect landfill design and site management practices which, in turn, influence decomposition rates. Finally, future trends in landfilling, and their relationship to gas production, will be examined. 19 refs., 2 figs., 3 tabs.

  6. Modelling gas generation for landfill.

    PubMed

    Chakma, Sumedha; Mathur, Shashi

    2016-09-27

    A methodology was developed to predict the optimum long-term spatial and temporal generation of landfill gases such as methane, carbon dioxide, ammonia, and hydrogen sulphide on post-closure landfill. The model incorporated the chemical and the biochemical processes responsible for the degradation of the municipal solid waste. The developed model also takes into account the effects of heterogeneity with different layers as observed at the site of landfills' morphology. The important parameters for gas generation due to biodegradation such as temperature, pH, and moisture content were incorporated. The maximum and the minimum generations of methane and hydrogen sulphide were observed. The rate of gas generation was found almost same throughout the depth after 30 years of landfill closure. The proposed model would be very useful for landfill engineering in the mining landfill gas and proper design for landfill gas management systems.

  7. ENGINEERING BULLETIN: LANDFILL COVERS

    EPA Science Inventory

    Landfill covers are used at Superfund sites to minimize surface water infiltration and control gas migration. In many cases covers are used in conjunction with other waste treatment technologies, such as slurry walls, ground water pump-and-treat systems, and gas collection. This ...

  8. NASA Bioreactor tissue culture

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  9. Indirect measurements of field-scale hydraulic conductivity of waste from two landfill sites.

    PubMed

    Fleming, I R

    2011-12-01

    Management and prediction of the movement and distribution of fluids in large landfills is important for various reasons. Bioreactor landfill technology shows promise, but in arid or semi-arid regions, the natural content of landfilled waste may be low, thus requiring addition of significant volumes of water. In more humid locations, landfills can become saturated, flooding gas collection systems and causing sideslope leachate seeps or other undesirable occurrences. This paper compares results from two different approaches to monitoring water in waste. At the Brock West Landfill in eastern Canada, positive pore pressures were measured at various depths in saturated waste. The downward seepage flux through the waste is known, thus the vertical saturated hydraulic conductivity of the waste at this landfill was determined to be 3 × 10(-7)cm/s. By comparison, the Spadina Landfill in western Canada is predominantly unsaturated. The infiltration of moisture into the waste was measured using moisture sensors installed in boreholes which determined arrival time for moisture fronts resulting from major precipitation events as well as longer-term change in moisture content resulting from unsaturated drainage during winter when frozen ground prevented infiltration. The unsaturated hydraulic conductivity calculated from these data ranged from approximately 10(-6)cm/s for the slow winter drainage in the absence of significant recharge to 10(-2)cm/s or higher for shallow waste subject to high infiltration through apparent preferential pathways. These two very different approaches to field-scale measurements of vertical hydraulic conductivity provide insight into the nature of fluid movement in saturated and unsaturated waste masses. It is suggested that the principles of unsaturated seepage apply reasonably well for landfilled waste and that the hydraulic behavior of waste is profoundly influenced by the nature and size of voids and by the degree of saturation prevailing in the

  10. Mathematical modelling of landfill gas migration in MSW sanitary landfills.

    PubMed

    Martín, S; Marañón, E; Sastre, H

    2001-10-01

    The laws that govern the displacement of landfill gas in a sanitary landfill are analysed. Subsequently, a 2-D finite difference flow model of a fluid in a steady state in a porous medium with infinite sources of landfill gas is proposed. The fact that landfill gas is continuously generated throughout the entire mass of the landfill differentiates this model from others extensively described in the literature and used in a variety of different applications, such as oil recovery, groundwater flow, etc. Preliminary results are then presented of the application of the model. Finally, the results obtained employing data from the literature and experimental assays carried out at the La Zoreda sanitary landfill (Asturias, Spain) are discussed and future lines of research are proposed.

  11. Development of a Zero-Headspace Aerobic Suspended Growth Bioreactor

    DTIC Science & Technology

    1994-08-01

    are metabolized via enzymatic -based oxidation reac- tions that use molecular oxygen as the electron acceptor. During the metabolic degradation of...biotreatment of contaminated soils (Zappi et al. 1993). DO is released from hydrogen peroxide because of its hydrolysis , which is mediated by metals...found in the soil matrix or through enzymatic -based degradation via catalases and peroxidases produced by microorganisms (Bajpai and Zappi 1994). These

  12. Effects of sulfur-metabolizing bacterial community diversity on H2S emission behavior in landfills with different operation modes.

    PubMed

    Fang, Yuan; Du, Yao; Hu, Lifang; Xu, Jing; Long, Yuyang; Shen, Dongsheng

    2016-11-01

    Hydrogen sulfide (H2S) is one of the major contributors to offensive odors from landfills, and its concentration differs under different operation modes. This study examined the distribution of H2S emission from different landfill depths under different operation modes (anaerobic, semi-aerobic, semi-aerobic transformation, and the three operation modes with additional leachate recirculation). The microbial community (especially the sulfur-metabolizing bacterial community) was investigated using high-throughput sequencing technology. The results showed that the semi-aerobic mode could substantially lower the risks of H2S pollution in landfills, which might be because of the difference in biological processes related to sulfur metabolism driven by functional microbes. A myriad of factors are responsible for mutually shaping the sulfur-metabolizing bacterial community composition in landfills that might subsequently affect the behavior of H2S emission in landfills. The differences in abundance of the genera Acinetobacter and Paracoccus (phylum Proteobacteria) caused by environmental factors might explain the differences in H2S emission. H2S odor control could be realized if the related functional microbe diversity can be influenced by adjustments to landfill operation.

  13. Effects of concentrated leachate injection modes on stabilization of landfilled waste.

    PubMed

    He, Ruo; Wei, Xiao-Meng; Chen, Min; Su, Yao; Tian, Bao-Hu

    2016-02-01

    Injection of concentrated leachate to landfills is a simple and cost-effective technology for concentrated leachate treatment. In this study, the effects of injection mode of concentrated leachate and its hydraulic loading rate on the stabilization of landfilled waste were investigated. Compared with the injection of concentrated leachate, the joint injection of leachate and concentrated leachate (1:1, v/v) was more beneficial to the degradation of landfilled waste and mitigated the discharge amount of pollutants at the hydraulic loading rate of 5.9 L m(-2) day(-1). As the hydraulic loading rate of the joint injection of leachate and concentrated leachate was increased from 5.9 to 17.6 L m(-2) day(-1), the organic matter, biologically degradable matter, and total nitrogen of landfilled waste were degraded more rapidly, with the degradation constant of the first-order kinetics of 0.005, 0.004, and 0.003, respectively. Additionally, NO2(-)-N and NO3(-)-N in the concentrated leachate could be well removed in the landfill bioreactors. These results showed that a joint injection of concentrated leachate and raw leachate might be a good way to relieve the inhibitory effect of high concentrations of toxic pollutants in the concentrated leachate and accelerate the stabilization of landfilled waste.

  14. Nitrogen removal pathway of anaerobic ammonium oxidation in on-site aged refuse bioreactor.

    PubMed

    Wang, Chao; Zhao, Youcai; Xie, Bing; Peng, Qing; Hassan, Muhammad; Wang, Xiaoyuan

    2014-05-01

    The nitrogen removal pathways and nitrogen-related functional genes in on-site three-stage aged refuse bioreactor (ARB) treating landfill leachate were investigated. It was found that on average 90.0% of CODCr, 97.6% of BOD5, 99.3% of NH4(+)-N, and 81.0% of TN were removed with initial CODCr, BOD5, NH4(+)-N, and TN concentrations ranging from 2323 to 2754, 277 to 362, 1237 to 1506, and 1251 to 1580 mg/L, respectively. Meanwhile, the functional genes amoA, nirS and anammox 16S rRNA gene were found to coexist in every bioreactor, and their relative proportions in each bioreactor were closely related to the pollutant removal performance of the corresponding bioreactor, which indicated the coexistence of multiple nitrogen removal pathways in the ARB. Detection of anammox expression proved the presence of the anammox nitrogen removal pathway during the process of recirculating mature leachate to the on-site ARB, which provides important information for nitrogen management in landfills.

  15. Claymax landfill cap

    SciTech Connect

    Selby, C.L.

    1989-12-15

    A commercial product called Claymax'' consisting of one-quarter inch of bentonite clay between two geotextile sheets is a candidate landfill cap to replace kaolin caps. A permeability apparatus incorporating a 20 foot water head was operated for 56 days to estimate a Claymax permeability of 2 {times} 10{sup {minus}9} cm/sec compared with 10{sup {minus}8}, the EPA max for a burial site cap. 1 fig.

  16. Landfills in karst terrains

    SciTech Connect

    Hughes, T.H. ); Memon, B.A.; LaMoreaux, P.E. )

    1994-06-01

    State and Federal regulations have established restrictions for location of hazardous waste and municipal, solid waste landfills. Regulations require owners/operators to demonstrate that the hydrogeology has been completely characterized at proposed landfills, and that locations for monitoring wells have been properly selected. Owners/operators are also required to demonstrate that engineering measures have been incorporated in the design of the municipal solid waste landfills, so that the site is not subject to destabilizing events, as a result of location in unstable areas, such as karst terrains. Karst terrains are typically underlain by limestone or dolomite, and may contain a broad continuum of karst features and karst activity. Preliminary investigation of candidate sites will allow ranking of the sites, rejection of some unsuitable sites, and selection of a few sites for additional studies. The complexity of hydrogeologic systems, in karst terrains, mandates thorough hydrogeologic studies to determine whether a specific site is, or can be rendered, suitable for a land disposal facility. Important components of hydrogeologic studies are: field mapping of structural and stratigraphic units; interpretation of sequential aerial photographs; test drilling and geophysical analyses; fracture analyses; seasonal variation in water-levels; spatial variation of hydraulic characteristics of the aquifer and aquiclude; velocity and direction of movement of ground water within aquifers; determination of control for recharge, discharge, and local base level; and evaluation of the effects of man's activities, such as pumping, dewatering and construction.

  17. Phytoremediation of landfill leachate

    SciTech Connect

    Jones, D.L. . E-mail: d.jones@bangor.ac.uk; Williamson, K.L.; Owen, A.G.

    2006-07-01

    Leachate emissions from landfill sites are of concern, primarily due to their toxic impact when released unchecked into the environment, and the potential for landfill sites to generate leachate for many hundreds of years following closure. Consequently, economically and environmentally sustainable disposal options are a priority in waste management. One potential option is the use of soil-plant based remediation schemes. In many cases, using either trees (including short rotation coppice) or grassland, phytoremediation of leachate has been successful. However, there are a significant number of examples where phytoremediation has failed. Typically, this failure can be ascribed to excessive leachate application and poor management due to a fundamental lack of understanding of the plant-soil system. On balance, with careful management, phytoremediation can be viewed as a sustainable, cost effective and environmentally sound option which is capable of treating 250 m{sup 3} ha{sup -1} yr{sup -1}. However, these schemes have a requirement for large land areas and must be capable of responding to changes in leachate quality and quantity, problems of scheme establishment and maintenance, continual environmental monitoring and seasonal patterns of plant growth. Although the fundamental underpinning science is well understood, further work is required to create long-term predictive remediation models, full environmental impact assessments, a complete life-cycle analysis and economic analyses for a wide range of landfill scenarios.

  18. Clinostats and bioreactors.

    PubMed

    Klaus, D M

    2001-06-01

    The environment created on Earth within a clinostat or Rotating Wall Vessel (RWV) bioreactor is often referred to as "simulated microgravity". Both devices utilize constant reorientation to effectively nullify cumulative sedimentation of particles. Neither, however, can fully reproduce the concurrent lack of structural deformation, displacement of intercellular components and/or reduced mass transfer in the extracellular fluid that occur in actual weightlessness. Parameters including density, viscosity, and even container geometry must each be considered to determine the overall gravity-dependent effects produced by either a clinostat or the RWV bioreactor; in addition, the intended application of these two devices differs considerably. A state of particle "motionlessness" relative to the surrounding bulk fluid, which is nearly analogous to the extracellular environment encountered under weightless conditions, can theoretically be achieved through clinorotation. The RWV bioreactor, on the other hand, while similarly maintaining cells in suspension as they continually "fall" through the medium under 1 g conditions, can also purposefully induce a perfusion of nutrients to and waste from the culture. A clinostat, therefore, is typically used in an attempt to reproduce the quiescent, unstirred fluid conditions achievable on orbit; while the RWV bioreactor ideally creates a low shear, but necessarily mixed, fluid environment that is optimized for suspension culture and tissue growth. Other techniques for exploring altered inertial environments, such as freefall, neutral buoyancy and electromagnetic levitation, can also provide unique insight into how gravity affects biological systems. Ultimately, all underlying biophysical principles thought to give rise to gravity-dependent physiological responses must be identified and thoroughly examined in order to accurately interpret data from flight experiments or ground-based microgravity analogs.

  19. Potential application of biocover soils to landfills for mitigating toluene emission.

    PubMed

    Su, Yao; Pei, Junshen; Tian, Baohu; Fan, Fengxi; Tang, Mengling; Li, Wei; He, Ruo

    2015-12-15

    Biocover soils have been demonstrated to be a good alternative cover material to mitigate CH4 emission from landfills. To evaluate the potential of biocover soil in mitigating emissions of non-methane volatile organic compounds (NMVOCs) from landfills, simulated cover soil columns with the influx of toluene (chosen as typical of NMVOCs) concentrations of 102-1336 mg m(-3) in the presence or absence of the major landfill gas components (i.e., CH4 and CO2) were conducted in this study. In the two experimental materials (waste biocover soils (WBS) and landfill cover soils (LCS)), higher toluene reduction was observed in WBS with respect to LCS. After the introduction of landfill gas, an increase of microbial diversity and relative abundance of toluene-degrading bacteria and methanotrophs occurred in WBS. To illustrate the role of toluene-degrading activity in mitigating toluene emissions through landfill covers, an analytical model was developed by incorporating the steady-state vapor transport with the first-order kinetics of aerobic biodegradation limited by O2 availability. This study demonstrated that biocover soils have great potential in applying to landfills for mitigating toluene emission to the atmosphere.

  20. Treatment of textile wastewater with membrane bioreactor: A critical review.

    PubMed

    Jegatheesan, Veeriah; Pramanik, Biplob Kumar; Chen, Jingyu; Navaratna, Dimuth; Chang, Chia-Yuan; Shu, Li

    2016-03-01

    Membrane bioreactor (MBR) technology has been used widely for various industrial wastewater treatments due to its distinct advantages over conventional bioreactors. Treatment of textile wastewater using MBR has been investigated as a simple, reliable and cost-effective process with a significant removal of contaminants. However, a major drawback in the operation of MBR is membrane fouling, which leads to the decline in permeate flux and therefore requires membrane cleaning. This eventually decreases the lifespan of the membrane. In this paper, the application of aerobic and anaerobic MBR for textile wastewater treatment as well as fouling and control of fouling in MBR processes have been reviewed. It has been found that long sludge retention time increases the degradation of pollutants by allowing slow growing microorganisms to establish but also contributes to membrane fouling. Further research aspects of MBR for textile wastewater treatment are also considered for sustainable operations of the process.

  1. Teaching Aerobic Fitness Concepts.

    ERIC Educational Resources Information Center

    Sander, Allan N.; Ratliffe, Tom

    2002-01-01

    Discusses how to teach aerobic fitness concepts to elementary students. Some of the K-2 activities include location, size, and purpose of the heart and lungs; the exercise pulse; respiration rate; and activities to measure aerobic endurance. Some of the 3-6 activities include: definition of aerobic endurance; heart disease risk factors;…

  2. Microbial Bioreactor Development in the ALS NSCORT

    NASA Astrophysics Data System (ADS)

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

    The NASA Specialized Center of Research and Training in Advanced Life Support (the ALS NSCORT), a partnership of Alabama A & M, Howard, and Purdue Universities, was established by NASA in 2002 to develop technologies that will reduce the Equivalent System Mass (ESM) of regenerative processes within future space life-support systems. A key focus area of NSCORT research has been the development of efficient microbial bioreactors for treatment of human, crop, and food-process wastes while enabling resource recovery. The approach emphasizes optimizing the energy-saving advantages of hydrolytic enzymes for biomass degradation, with focus on treatment of solid wastes including crop residue, paper, food, and human metabolic wastes, treatment of greywater, cabin air, off-gases from other treatment systems, and habitat condensate. This summary includes important findings from those projects, status of technology development, and recommendations for next steps. The Plant-based Anaerobic-Aerobic Bioreactor-Linked Operation (PAABLO) system was developed to reduce crop residue while generating energy and/or food. Plant residues initially were added directly to the bioreactor, and recalcitrant residue was used as a substrate for growing plants or mushrooms. Subsequently, crop residue was first pretreated with fungi to hydrolyze polymers recalcitrant to bacteria, and leachate from the fungal beds was directed to the anaerobic digester. Exoenzymes from the fungi pre-soften fibrous plant materials, improving recovery of materials that are more easily biodegraded to methane that can be used for energy reclamation. An Autothermal Thermophilic Aerobic Digestion (ATAD) system was developed for biodegradable solid wastes. Objectives were to increase water and nutrient recovery, reduce waste volume, and inactivate pathogens. Operational parameters of the reactor were optimized for degradation and resource recovery while minimizing system requirements and footprint. The start-up behavior

  3. Landfill Gas Energy Project Data and Landfill Technical Data

    EPA Pesticide Factsheets

    This page provides data from the LMOP Database for U.S. landfills and LFG energy projects in Excel files, a map of project and candidate landfill counts by state, project profiles for a select group of projects, and information about Project Expo sites.

  4. Oscillating Cell Culture Bioreactor

    NASA Technical Reports Server (NTRS)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  5. Research on leachate recirculation from different types of landfills

    SciTech Connect

    Wang Qi . E-mail: wangqi@craes.org.cn; Matsufuji, Yasushi; Dong Lu; Huang Qifei; Hirano, Fumiaki; Tanaka, Ayako

    2006-07-01

    Landfills can produce a great amount of leachate containing highly concentrated organic matter. This is especially true for the initial leachate from landfilled municipal solid wastes (MSW) that generally has concentrations of COD{sub Cr} and BOD{sub 5} up to 80,000 and 50,000 mg/L, respectively. The leachate could be disposed by means of recirculating technique, which decomposes the organics through the action of proliferating microorganisms and thereby purifies the leachate, and simultaneously accelerates organic decomposition through water saturation control. Data from experimental results indicated that leachate recirculating could reduce the organic concentration considerably, with a maximum reduction rate of COD{sub Cr} over 95%; and, using a semi-aerobic process, NH{sub 3}-N concentration of treated leachate could be under 10 mg/L. In addition, the organic concentration in MSW decreased greatly.

  6. Toxicological characterization of a novel wastewater treatment process using EDTA-Na2Zn as draw solution (DS) for the efficient treatment of MBR-treated landfill leachate.

    PubMed

    Niu, Aping; Ren, Yi-Wei; Yang, Li; Xie, Shao-Lin; Jia, Pan-Pan; Zhang, Jing-Hui; Wang, Xiao; Li, Jing; Pei, De-Sheng

    2016-07-01

    Landfill leachate has become an important source of environmental pollution in past decades, due to the increase of waste volume. Acute toxic and genotoxic hazards to organisms can be caused by landfill leachate. Thus, how to efficiently recover water from landfill leachate and effectively eliminate combined toxicity of landfill leachate are the most pressing issues in waste management. In this study, EDTA-Na2Zn as draw solution (DS) was used to remove the toxicity of membrane bioreactor-treated landfill leachate (MBR-treated landfill leachate) in forward osmosis (FO) process, and nanofiltration (NF) was designed for recovering the diluted DS. Zebrafish and human cells were used for toxicity assay after the novel wastewater treatment process using EDTA-Na2Zn as DS. Results showed that the water recovery rate of MBR-treated landfill leachate (M-LL) in FO membrane system could achieve 66.5% and 71.2% in the PRO and FO mode respectively, and the diluted DS could be efficiently recovered by NF. Toxicity tests performed by using zebrafish and human cells showed that M-LL treated by EDTA-Na2Zn had no toxicity effect on zebrafish larvae and human cells, but it had very slight effect on zebrafish embryos. In conclusion, all results indicated that EDTA-Na2Zn as DS can effectively eliminate toxicity of landfill leachate and this method is economical and eco-friendly for treatment of different types of landfill leachate.

  7. A comparative examination of MBR and SBR performance for the treatment of high-strength landfill leachate.

    PubMed

    El-Fadel, M; Hashisho, J

    2014-09-01

    The management of landfill leachate is challenging, with relatively limited work targeting high-strength leachate. In this study, the performance of the membrane bioreactor (MBR) and sequencing batch reactor (SBR) technologies are compared in treating high-strength landfill leachate. The MBR exhibited a superior performance with removal efficiencies exceeding 95% for BOD5, TN, and NH3 and an improvement on SBR efficiencies ranging between 21 and 34%. The coupled experimental results contribute in filling a gap toward improving the management of high-strength landfill leachate and providing comparative guidelines or selection criteria and limitations for MBR and SBR applications. Implications: While the sequencing batch reactor (SBR) technology offers some flexibility in terms of cycle time and sequence, its performance is constrained when considering landfill leachate associated with significant variations in quality and quantity. Combining membrane separation and biodegradation processes or the membrane bioreactor (MBR) technology improved removal efficiencies significantly. In the context of leachate management using the MBR technology, more efforts have targeted low-strength leachate with limited attempts at moderate to high strength leachate. In this study, the SBR and MBR technologies were tested under different operating conditions to compare and evaluate their feasibility for the management of high-strength leachate from a full-scale operating landfill. Such a comparison has not been reported for high-strength leachate.

  8. Design challenges for space bioreactors

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Petersen, G. R.

    1989-01-01

    The design of bioreactors for operation under conditions of microgravity presents problems and challenges. Absence of a significant body force such as gravity can have profound consequences for interfacial phenomena. Marangoni convection can no longer be overlooked. Many speculations on the advantages and benefits of microgravity can be found in the literature. Initial bioreactor research considerations for space applications had little regard for the suitability of the designs for conditions of microgravity. Bioreactors can be classified in terms of their function and type of operation. The complex interaction of parameters leading to optimal design and operation of a bioreactor is illustrated by the JSC mammalian cell culture system. The design of a bioreactor is strongly dependent upon its intended use as a production unit for cell mass and/or biologicals or as a research reactor for the study of cell growth and function. Therefore a variety of bioreactor configurations are presented in rapid summary. Following this, a rationale is presented for not attempting to derive key design parameters such as the oxygen transfer coefficient from ground-based data. A set of themes/objectives for flight experiments to develop the expertise for design of space bioreactors is then proposed for discussion. These experiments, carried out systematically, will provide a database from which engineering tools for space bioreactor design will be derived.

  9. Changing face of the landfill

    SciTech Connect

    1995-10-01

    Integrated approach at Oregon landfill diverts wood and yard trimmings, while turning methane into power for 1,800 homes. Opened in the 1940`s as an open burn dump, Coffin Butte has evolved over the years into a sophisticated waste management facility incorporating ambitious recovery programs. While some of this change has been driven by regulatory demands, many of Valley Landfill`s innovations have come in response to market opportunities. Valley Landfill`s Processing and Recovery Center (PRC) is located a half mile down the road from the landfill site. Opened in 1990, the facility recycles urban wood waste, yard trimmings and street sweepings. The heart of this operation is a 500 hp horizontal feed, fixed-hammer grinder. Although this machine is typically used only for wood grinding, PRC was able to adapt it to handle both wood and yard trimmings by installing special feed roll assembly to compress green waste passing over the infeed belt. The facility handles approximately 40,000 cubic yards of loose green material and produces 15,000 to 18,000 yards of compost. The finished product is run through a trommel with a 5/8 inch mesh screen. Most of the compost is sold in bulk to area garden centers. A portion is processed through a 3/8 inch shaker screen and sold to a local company for use in bagged soil products. Valley Landfill is a partner in an ambitious project to generate electricity from landfill biogas.

  10. Stabilizing Waste Materials for Landfills

    ERIC Educational Resources Information Center

    Environmental Science and Technology, 1977

    1977-01-01

    The test procedures used to evaluate the suitability of landfilled materials of varying stability and to determine the leachate from such materials are reviewed. A process for stabilizing a mixture of sulfur dioxide sludge, fly ash, and bottom ash with lime and other additives for deposition in landfills is detailed. (BT)

  11. Landfill to Learning Facility

    NASA Astrophysics Data System (ADS)

    Venner, L.; Lewicki, S.

    2008-11-01

    Engaging ``K-to-Gray'' audiences (children, families, and older adults) in scientific exploration and discovery is the main goal of the New Jersey Meadowlands Commission (NJMC) Center for Environmental and Scientific Education (CESE) and the William D. McDowell Observatory located in Lyndhurst, NJ and operated by Ramapo College of New Jersey. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED--certified building (certification pending) and William D. McDowell observatory brings hands-on scientific experiences to the ˜25,000 students and ˜15,000 visitors that come to our site from the NY/NJ region each year.

  12. The decay of wood in landfills in contrasting climates in Australia

    SciTech Connect

    Ximenes, Fabiano; Björdal, Charlotte; Cowie, Annette; Barlaz, Morton

    2015-07-15

    Highlights: • We examine decay in wood from landfills in contrasting environments in Australia. • Analysis is based on changes in chemical composition and microscopy. • Climate did not influence levels of decay observed. • Microscopy of retrieved samples revealed most of the decay was aerobic in nature. • Current default factors for wood decay in landfills overestimate methane emissions. - Abstract: Wood products in landfill are commonly assumed to decay within several decades, returning the carbon contained therein to the atmosphere, with about half the carbon released as methane. However, the rate and extent of decay is not well known, as very few studies have examined the decay of wood products in landfills. This study reports on the findings from landfill excavations conducted in the Australian cities of Sydney and Cairns located in temperate and tropical environments, respectively. The objective of this study was to determine whether burial of the wood in warmer, more tropical conditions in Cairns would result in greater levels of decay than occurs in the temperate environment of Sydney. Wood samples recovered after 16–44 years in landfill were examined through physical, chemical and microscopic analyses, and compared with control samples to determine the carbon loss. There was typically little or no decay in the wood samples analysed from the landfill in Sydney. Although there was significant decay in rainforest wood species excavated from Cairns, decay levels for wood types that were common to both Cairns and Sydney landfills were similar. The current Intergovernmental Panel on Climate Change (IPCC, 2006) default decay factor for organic materials in landfills is 50%. In contrast, the carbon loss determined for Pinus radiata recovered from Sydney and Cairns landfills was 7.9% and 4.4%, respectively, and 0% for Agathis sp. This suggests that climate did not influence decay, and that the more extensive levels of decay observed for some wood samples

  13. The decay of wood in landfills in contrasting climates in Australia.

    PubMed

    Ximenes, Fabiano; Björdal, Charlotte; Cowie, Annette; Barlaz, Morton

    2015-07-01

    Wood products in landfill are commonly assumed to decay within several decades, returning the carbon contained therein to the atmosphere, with about half the carbon released as methane. However, the rate and extent of decay is not well known, as very few studies have examined the decay of wood products in landfills. This study reports on the findings from landfill excavations conducted in the Australian cities of Sydney and Cairns located in temperate and tropical environments, respectively. The objective of this study was to determine whether burial of the wood in warmer, more tropical conditions in Cairns would result in greater levels of decay than occurs in the temperate environment of Sydney. Wood samples recovered after 16-44years in landfill were examined through physical, chemical and microscopic analyses, and compared with control samples to determine the carbon loss. There was typically little or no decay in the wood samples analysed from the landfill in Sydney. Although there was significant decay in rainforest wood species excavated from Cairns, decay levels for wood types that were common to both Cairns and Sydney landfills were similar. The current Intergovernmental Panel on Climate Change (IPCC, 2006) default decay factor for organic materials in landfills is 50%. In contrast, the carbon loss determined for Pinus radiata recovered from Sydney and Cairns landfills was 7.9% and 4.4%, respectively, and 0% for Agathis sp. This suggests that climate did not influence decay, and that the more extensive levels of decay observed for some wood samples from Cairns indicates that those wood types were more susceptible to biodegradation. Microscopic analyses revealed that most decay patterns observed in samples analysed from Sydney were consistent with aerobic fungal decay. Only a minor portion of the microbial decay was due to erosion bacteria active in anaerobic/near anaerobic environments. The findings of this study strongly suggest that models that adopt

  14. Aerobic and anaerobic cellulase production by Cellulomonas uda.

    PubMed

    Poulsen, Henrik Vestergaard; Willink, Fillip Wolfgang; Ingvorsen, Kjeld

    2016-10-01

    Cellulomonas uda (DSM 20108/ATCC 21399) is one of the few described cellulolytic facultative anaerobes. Based on these characteristics, we initiated a physiological study of C. uda with the aim to exploit it for cellulase production in simple bioreactors with no or sporadic aeration. Growth, cellulase activity and fermentation product formation were evaluated in different media under both aerobic and anaerobic conditions and in experiments where C. uda was exposed to alternating aerobic/anaerobic growth conditions. Here we show that C. uda behaves as a true facultative anaerobe when cultivated on soluble substrates such as glucose and cellobiose, but for reasons unknown cellulase activity is only induced under aerobic conditions on insoluble cellulosic substrates and not under anaerobic conditions. These findings enhance knowledge on the limited number of described facultative cellulolytic anaerobes, and in addition it greatly limits the utility of C. uda as an 'easy to handle' cellulase producer with low aeration demands.

  15. Proof-of-concept of a novel micro-bioreactor for fast development of industrial bioprocesses.

    PubMed

    Reis, N; Gonçalves, C N; Vicente, A A; Teixeira, J A

    2006-11-05

    The experimental performance of a novel micro-bioreactor envisaged for parallel screening and development of industrial bioprocesses has been tested in this work. The micro-bioreactor with an internal volume of 4.5 mL is operated under oscillatory flow mixing (OFM), where a controllable mixing and mass transfer rates are achieved under batch or continuous laminar flow conditions. Several batch fermentations with a flocculent Saccharomyces cerevisiae strain were carried out at initial glucose concentrations (S(0)) range of approximately 5-20 g/L and compared to yeast growth kinetics in a stirred tank (ST) bioreactor. Aerobic fermentations were monitored ex situ in terms of pH, DO, glucose consumption, and biomass and ethanol production (wherever applicable). An average biomass production increase of 83% was obtained in the micro-bioreactor when compared with the ST, with less 93.6% air requirements. It also corresponded to a 214% increase on biomass production when compared with growth in a shaken flask (SF) at S(0) = 20 g/L. Further anaerobic fermentations at the same initial glucose concentration ranges gave the opportunity to use state-of-the-art fiber optics technology for on-line and real-time monitoring of this bioprocess. Time profiles of biomass concentration (measured as optical density (OD)) were very similar in the ST bioreactor and in the micro-bioreactor, with a highly reproducible yeast growth in these two scale-down platforms.

  16. Methane emissions from MBT landfills

    SciTech Connect

    Heyer, K.-U. Hupe, K.; Stegmann, R.

    2013-09-15

    Highlights: • Compilation of methane generation potential of mechanical biological treated (MBT) municipal solid waste. • Impacts and kinetics of landfill gas production of MBT landfills, approach with differentiated half-lives. • Methane oxidation in the waste itself and in soil covers. • Estimation of methane emissions from MBT landfills in Germany. - Abstract: Within the scope of an investigation for the German Federal Environment Agency (“Umweltbundesamt”), the basics for the estimation of the methane emissions from the landfilling of mechanically and biologically treated waste (MBT) were developed. For this purpose, topical research including monitoring results regarding the gas balance at MBT landfills was evaluated. For waste treated to the required German standards, a methane formation potential of approximately 18–24 m{sup 3} CH{sub 4}/t of total dry solids may be expected. Monitoring results from MBT landfills show that a three-phase model with differentiated half-lives describes the degradation kinetics in the best way. This is due to the fact that during the first years of disposal, the anaerobic degradation processes still proceed relatively intensively. In addition in the long term (decades), a residual gas production at a low level is still to be expected. Most of the soils used in recultivation layer systems at German landfills show a relatively high methane oxidation capacity up to 5 l CH{sub 4}/(m{sup 2} h). However, measurements at MBT disposal sites indicate that the majority of the landfill gas (in particular at non-covered areas), leaves the landfill body via preferred gas emission zones (hot spots) without significant methane oxidation. Therefore, rather low methane oxidation factors are recommended for open and temporarily covered MBT landfills. Higher methane oxidation rates can be achieved when the soil/recultivation layer is adequately designed and operated. Based on the elaborated default values, the First Order Decay (FOD

  17. Methane production from food waste leachate in laboratory-scale simulated landfill.

    PubMed

    Behera, Shishir Kumar; Park, Jun Mo; Kim, Kyeong Ho; Park, Hung-Suck

    2010-01-01

    Due to the prohibition of food waste landfilling in Korea from 2005 and the subsequent ban on the marine disposal of organic sludge, including leachate generated from food waste recycling facilities from 2012, it is urgent to develop an innovative and sustainable disposal strategy that is eco-friendly, yet economically beneficial. In this study, methane production from food waste leachate (FWL) in landfill sites with landfill gas recovery facilities was evaluated in simulated landfill reactors (lysimeters) for a period of 90 d with four different inoculum-substrate ratios (ISRs) on volatile solid (VS) basis. Simultaneous biochemical methane potential batch experiments were also conducted at the same ISRs for 30 d to compare CH(4) yield obtained from lysimeter studies. Under the experimental conditions, a maximum CH(4) yield of 0.272 and 0.294 L/g VS was obtained in the batch and lysimeter studies, respectively, at ISR of 1:1. The biodegradability of FWL in batch and lysimeter experiments at ISR of 1:1 was 64% and 69%, respectively. The calculated data using the modified Gompertz equation for the cumulative CH(4) production showed good agreement with the experimental result obtained from lysimeter study. Based on the results obtained from this study, field-scale pilot test is required to re-evaluate the existing sanitary landfills with efficient leachate collection and gas recovery facilities as engineered bioreactors to treat non-hazardous liquid organic wastes for energy recovery with optimum utilization of facilities.

  18. Microtechnology in space bioreactors.

    PubMed

    Walther, I; van der Schoot, B; Boillat, M; Muller, O; Cogoli, A

    1999-03-01

    Space biology is a young and rapidly developing discipline comprising basic research and biotechnology. In the next decades it will play a prominent role in the International Space Station (ISS). Therefore, there is an increasing demand for sophisticated instrumentation to satisfy the requirements of the future projects in space biology. Bioreactors will be needed to supply fresh living material (cells and tissues) either to study still obscure basic biological mechanisms or to develop profitable bioprocesses which will take advantage of the peculiar microgravity conditions. Since more than twenty years, the Space Biology Group of the ETHZ is carrying out research projects in space (Space Shuttle/Spacelab, MIR Station, satellites, and sounding rockets) that involve also the development of space-qualified instrumentation. In the last ten years we have developed, in collaboration with Mecanex SA, Nyon, and the Institute of Microtechnology of the University of Neuchatel, a space bioreactor for the continuous culture of yeast cells under controlled conditions. Sensors, pH control, nutrients pump and fluid flowmeter are based on state-of-the-art silicon technology. After two successful space flights, a further improved version is presently prepared for a flight in the year 2000.

  19. Sensing in tissue bioreactors

    NASA Astrophysics Data System (ADS)

    Rolfe, P.

    2006-03-01

    Specialized sensing and measurement instruments are under development to aid the controlled culture of cells in bioreactors for the fabrication of biological tissues. Precisely defined physical and chemical conditions are needed for the correct culture of the many cell-tissue types now being studied, including chondrocytes (cartilage), vascular endothelial cells and smooth muscle cells (blood vessels), fibroblasts, hepatocytes (liver) and receptor neurones. Cell and tissue culture processes are dynamic and therefore, optimal control requires monitoring of the key process variables. Chemical and physical sensing is approached in this paper with the aim of enabling automatic optimal control, based on classical cell growth models, to be achieved. Non-invasive sensing is performed via the bioreactor wall, invasive sensing with probes placed inside the cell culture chamber and indirect monitoring using analysis within a shunt or a sampling chamber. Electroanalytical and photonics-based systems are described. Chemical sensing for gases, ions, metabolites, certain hormones and proteins, is under development. Spectroscopic analysis of the culture medium is used for measurement of glucose and for proteins that are markers of cell biosynthetic behaviour. Optical interrogation of cells and tissues is also investigated for structural analysis based on scatter.

  20. Sour landfill gas problem solved

    SciTech Connect

    Nagl, G.; Cantrall, R.

    1996-05-01

    In Broward County, Fla., near Pompano Beach, Waste Management of North America (WMNA, a subsidiary of WMX Technologies, Oak Brook, IL) operates the Central Sanitary Landfill and Recycling Center, which includes the country`s largest landfill gas-to-energy plant. The landfill consists of three collection sites: one site is closed, one is currently receiving garbage, and one will open in the future. Approximately 9 million standard cubic feet (scf) per day of landfill gas is collected from approximately 300 wells spread over the 250-acre landfill. With a dramatic increase of sulfur-containing waste coming to a South Florida landfill following Hurricane Andrew, odors related to hydrogen sulfide became a serious problem. However, in a matter of weeks, an innovative desulfurization unit helped calm the landfill operator`s fears. These very high H{sub 2}S concentrations caused severe odor problems in the surrounding residential area, corrosion problems in the compressors, and sulfur dioxide (SO{sub 2}) emission problems in the exhaust gas from the turbine generators.

  1. Cells growing in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. Shown here, clusters of cells slowly spin inside a bioreactor. On Earth, the cells continually fall through the buffer medium and never hit bottom. In space, they are naturally suspended. Rotation ensures gentle stirring so waste is removed and fresh nutrient and oxygen are supplied. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  2. Metal loss from treated wood products in contact with municipal solid waste landfill leachate.

    PubMed

    Dubey, Brajesh; Townsend, Timothy; Solo-Gabriele, Helena

    2010-03-15

    The research presented in this paper evaluates the potential impact of municipal solid waste (MSW) landfill leachate quality on the loss of metals from discarded treated wood during disposal. The loss of arsenic (As), chromium (Cr), copper (Cu), and boron (B) from several types of pressure-treated wood (CCA: chromated copper arsenate, ACQ: alkaline copper quaternary, CBA: copper boron azole, and DOT: disodium octaborate tetrahydrate) using leachate collected from 26 MSW landfills in Florida was examined. The toxicity characteristic leaching procedure (TCLP), the synthetic precipitation leaching procedure (SPLP), and California's waste extraction test (WET) were also performed. The results suggested that loss of preservative components was influenced by leachate chemistry. Copper loss from CCA-, ACQ- and CBA-treated wood was similar in magnitude when in contact with landfill leachates compared to synthetic TCLP and SPLP solutions. Ammonia was found as one of the major parameters influencing the leaching of Cu from treated wood when leached with MSW landfill leachates. The results suggest that disposal of ACQ- and CBA-treated wood in substantial quantity in MSW landfills may elevate the Cu concentration in the leachate; this could be of potential concern, especially for a bioreactor MSW landfill in which relatively higher ammonia concentrations in leachate have been reported in recent literature. For the As, Cr and B the concentrations observed with the landfill leachate as the leaching solutions were over a range from some sample showing the concentrations below and some showing above the observed value from corresponding SPLP and TCLP tests. In general the WET test showed the highest concentrations.

  3. Greenhouse gas emissions from landfill leachate treatment plants: a comparison of young and aged landfill.

    PubMed

    Wang, Xiaojun; Jia, Mingsheng; Chen, Xiaohai; Xu, Ying; Lin, Xiangyu; Kao, Chih Ming; Chen, Shaohua

    2014-07-01

    With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH4 emissions were observed from the fresh leachate storage pond, with the fluxes values (2219-26,489 mg Cm(-2)h(-1)) extremely higher than those of N2O (0.028-0.41 mg Nm(-2)h(-1)). In contrast, the emission values for both CH4 and N2O were low for the aged leachate tank. N2O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8-12% of the removal of N-species gases. Per capita, the N2O emission based on both leachate treatment systems was estimated to be 7.99 g N2O-N capita(-1)yr(-1). An increase of 80% in N2O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO2, with a small portion as CH4 (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO(2) eq yr(-1), respectively, for a total that could be transformed to 9.09 kg CO(2) eq capita(-1)yr(-1).

  4. Astronomy on a Landfill

    NASA Astrophysics Data System (ADS)

    Venner, L.

    2008-11-01

    Engaging ``K-to-Gray'' audiences (children, families, and older adults) in astronomical activities is one of the main goals of the New Jersey Meadowlands Commission Center for Environmental and Scientific Education (CESE) and the William D. McDowell Observatory located in Lyndhurst, NJ, operated by Ramapo College of New Jersey. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED--certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of the International Year of Astronomy 2009 (IYA2009) to the ˜25,000 students and ˜15,000 visitors that visit our site from the NY/NJ region each year.

  5. Sanitary landfill groundwater monitoring report

    SciTech Connect

    Not Available

    1993-02-01

    The Sanitary Landfill at the Savannah River Site (SRS) is composed of the original 32-acre landfill, plus expansion areas to the north and south that added 16 and 22 acres, respectively, to the facility. The landfill is subject to the requirements of the Resource Conservation and Recovery Act and currently operates under South Carolina Department of Health and Environmental Control (SCDHEC) Domestic Waste Permit 87A. Fifty-seven wells of the LFW series monitor the groundwater quality in Steed Pond Aquifer (formerly Aquifer Zone I/IIC[sub 2]) (Water Table) beneath the Sanitary Landfill. These wells are sampled quarterly for certain indicator parameters, inorganics, metals, radionuclides, volatile organics, and other constituents as part of the SRS Groundwater Monitoring Program and to comply with the SCDHEC domestic waste permit. This report reviews the 1992 activities of the SRS Groundwater Monitoring Program.

  6. Landfill Gas Energy Benefits Calculator

    EPA Pesticide Factsheets

    This page contains the LFG Energy Benefits Calculator to estimate direct, avoided, and total greenhouse gas reductions, as well as environmental and energy benefits, for a landfill gas energy project.

  7. Where Should the Landfill Go?

    ERIC Educational Resources Information Center

    Fazio, Rosario P.; McFaden, Dennis

    1993-01-01

    Describes a project where students were involved in finding the most suitable site for a landfill in their community. This two-month project was conducted using team teaching. Two twelfth grade geoscience classes were involved. (PR)

  8. Spiral vane bioreactor

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor)

    1991-01-01

    A spiral vane bioreactor of a perfusion type is described in which a vertical chamber, intended for use in a microgravity condition, has a central rotating filter assembly and has flexible membranes disposed to rotate annularly about the filter assembly. The flexible members have end portions disposed angularly with respect to one another. A fluid replenishment medium is input from a closed loop liquid system to a completely liquid filled chamber containing microcarrier beads, cells and a fluid medium. Output of spent medium is to the closed loop. In the closed loop, the output and input parameters are sensed by sensors. A manifold permits recharging of the nutrients and pH adjustment. Oxygen is supplied and carbon dioxide and bubbles are removed and the system is monitored and controlled by a microprocessor.

  9. Controlled-Turbulence Bioreactors

    NASA Technical Reports Server (NTRS)

    Wolf, David A.; Schwartz, Ray; Trinh, Tinh

    1989-01-01

    Two versions of bioreactor vessel provide steady supplies of oxygen and nutrients with little turbulence. Suspends cells in environment needed for sustenance and growth, while inflicting less damage from agitation and bubbling than do propeller-stirred reactors. Gentle environments in new reactors well suited to delicate mammalian cells. One reactor kept human kidney cells alive for as long as 11 days. Cells grow on carrier beads suspended in liquid culture medium that fills cylindrical housing. Rotating vanes - inside vessel but outside filter - gently circulates nutrient medium. Vessel stationary; magnetic clutch drives filter cylinder and vanes. Another reactor creates even less turbulence. Oxygen-permeable tubing wrapped around rod extending along central axis. Small external pump feeds oxygen to tubing through rotary coupling, and oxygen diffuses into liquid medium.

  10. Membrane Bioreactor With Pressure Cycle

    NASA Technical Reports Server (NTRS)

    Efthymiou, George S.; Shuler, Michael L.

    1991-01-01

    Improved class of multilayer membrane bioreactors uses convention forced by differences in pressure to overcome some of diffusional limitations of prior bioreactors. In reactor of new class, flow of nutrient solution reduces adverse gradients of concentration, keeps cells supplied with fresh nutrient, and sweeps away products faster than diffusion alone. As result, overall yield and rate of reaction increased. Pressures in sweeping gas and nutrient alternated to force nutrient liquid into and out of biocatalyst layer through hyrophilic membrane.

  11. Bioreactors and fermentation. (Latest citations from the Life Sciences Collection datab base). Published Search

    SciTech Connect

    Not Available

    1992-05-01

    The bibliography contains citations concerning the use of bioreactors in fermentation processes. Topics include aerobic and anaerobic technologies involving yeasts, microorganisms, and enzymes. These technologies are useful in the production of ethanol, methanol (methane), butanol, organic acids, protein enhancers, and nitrogen enhancers in the dairy, agricultural, food, beverage processing, and medical industries. (Contains a minimum of 230 citations and includes a subject term index and title list.)

  12. Numerical simulation of landfill aeration using computational fluid dynamics.

    PubMed

    Fytanidis, Dimitrios K; Voudrias, Evangelos A

    2014-04-01

    The present study is an application of Computational Fluid Dynamics (CFD) to the numerical simulation of landfill aeration systems. Specifically, the CFD algorithms provided by the commercial solver ANSYS Fluent 14.0, combined with an in-house source code developed to modify the main solver, were used. The unsaturated multiphase flow of air and liquid phases and the biochemical processes for aerobic biodegradation of the organic fraction of municipal solid waste were simulated taking into consideration their temporal and spatial evolution, as well as complex effects, such as oxygen mass transfer across phases, unsaturated flow effects (capillary suction and unsaturated hydraulic conductivity), temperature variations due to biochemical processes and environmental correction factors for the applied kinetics (Monod and 1st order kinetics). The developed model results were compared with literature experimental data. Also, pilot scale simulations and sensitivity analysis were implemented. Moreover, simulation results of a hypothetical single aeration well were shown, while its zone of influence was estimated using both the pressure and oxygen distribution. Finally, a case study was simulated for a hypothetical landfill aeration system. Both a static (steadily positive or negative relative pressure with time) and a hybrid (following a square wave pattern of positive and negative values of relative pressure with time) scenarios for the aeration wells were examined. The results showed that the present model is capable of simulating landfill aeration and the obtained results were in good agreement with corresponding previous experimental and numerical investigations.

  13. Modelling of transport and biogeochemical processes in pollution plumes: Vejen landfill, Denmark

    NASA Astrophysics Data System (ADS)

    Brun, Adam; Engesgaard, Peter; Christensen, Thomas H.; Rosbjerg, Dan

    2002-01-01

    A biogeochemical transport code is used to simulate leachate attenuation, biogeochemical processes, and development of redox zones in a pollution plume downstream of the Vejen landfill in Denmark. Calibration of the degradation parameters resulted in a good agreement with the observed distribution in the plume of a number of species, such as dissolved organic carbon (DOC), Fe 2+, NO 3-, HCO 3-, SO 42-, CH 4, and pH. The simulated redox zones agree with observations confirming that the Fe-reducing zone played an important role in the attenuation of the DOC plume. Effective first-order rate constants for every redox zone were determined giving DOC half-lives ranging from 100 to 1-2 days going from the methanogenic to the aerobic zone. The order of decrease in DOC half-lives from the anaerobic to the aerobic zone corresponds to findings at other landfills.

  14. Nitrogen removal by Providencia rettgeri strain YL with heterotrophic nitrification and aerobic denitrification.

    PubMed

    Ye, Jun; Zhao, Bin; An, Qiang; Huang, Yuan-Sheng

    2016-09-01

    Providencia rettgeri strain YL shows the capability of nitrogen removal under sole aerobic conditions. By using isotope ratio mass spectrometry, (15)N-labelled N2O and N2 were detected in aerobic batch cultures containing [Formula: see text], [Formula: see text] or [Formula: see text]. Strain YL converted [Formula: see text], [Formula: see text] and [Formula: see text] to produce more N2O than N2 in the presence of [Formula: see text]. An (15)N isotope tracing experiment confirmed that the nitrogen removal pathway of strain YL was heterotrophic nitrification-aerobic denitrification. The optimal treatment conditions for nitrogen removal were pH of 8, C/N ratio of 12, temperature of 25°C and shaking speed of 105 rpm. A continuous aerobic bioreactor inoculated with strain YL was developed. With an influent [Formula: see text] concentration of 90-200 mg/L, the [Formula: see text] removal efficiency ranged from 80% to 97% and the total nitrogen removal efficiency ranged from 72% to 95%. The nitrogen balance in the continuous bioreactor revealed that approximately 35-52% of influent [Formula: see text] was denitrified aerobically to form gaseous nitrogen. These findings show that the P. rettgeri strain YL has potential application in wastewater treatment for nitrogen removal under sole aerobic conditions.

  15. Methane emissions from MBT landfills.

    PubMed

    Heyer, K-U; Hupe, K; Stegmann, R

    2013-09-01

    Within the scope of an investigation for the German Federal Environment Agency ("Umweltbundesamt"), the basics for the estimation of the methane emissions from the landfilling of mechanically and biologically treated waste (MBT) were developed. For this purpose, topical research including monitoring results regarding the gas balance at MBT landfills was evaluated. For waste treated to the required German standards, a methane formation potential of approximately 18-24 m(3)CH(4)/t of total dry solids may be expected. Monitoring results from MBT landfills show that a three-phase model with differentiated half-lives describes the degradation kinetics in the best way. This is due to the fact that during the first years of disposal, the anaerobic degradation processes still proceed relatively intensively. In addition in the long term (decades), a residual gas production at a low level is still to be expected. Most of the soils used in recultivation layer systems at German landfills show a relatively high methane oxidation capacity up to 5 l CH(4)/(m(2)h). However, measurements at MBT disposal sites indicate that the majority of the landfill gas (in particular at non-covered areas), leaves the landfill body via preferred gas emission zones (hot spots) without significant methane oxidation. Therefore, rather low methane oxidation factors are recommended for open and temporarily covered MBT landfills. Higher methane oxidation rates can be achieved when the soil/recultivation layer is adequately designed and operated. Based on the elaborated default values, the First Order Decay (FOD) model of the IPCC Guidelines for National Greenhouse Gas Inventories, 2006, was used to estimate the methane emissions from MBT landfills. Due to the calculation made by the authors emissions in the range of 60,000-135,000 t CO(2-eq.)/a for all German MBT landfills can be expected. This wide range shows the uncertainties when the here used procedure and the limited available data are applied

  16. Microbial nitrogen transformation potential in surface run-off leachate from a tropical landfill

    SciTech Connect

    Mangimbulude, Jubhar C.; Straalen, Nico M. van; Roeling, Wilfred F.M.

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Microbial nitrogen transformations can alleviate toxic ammonium discharge. Black-Right-Pointing-Pointer Aerobic ammonium oxidation was rate-limiting in Indonesian landfill leachate. Black-Right-Pointing-Pointer Organic nitrogen ammonification was most dominant. Black-Right-Pointing-Pointer Anaerobic nitrate reduction and ammonium oxidation potential were also high. Black-Right-Pointing-Pointer A two-stage aerobic-anaerobic nitrogen removal system needs to be implemented. - Abstract: Ammonium is one of the major toxic compounds and a critical long-term pollutant in landfill leachate. Leachate from the Jatibarang landfill in Semarang, Indonesia, contains ammonium in concentrations ranging from 376 to 929 mg N L{sup -1}. The objective of this study was to determine seasonal variation in the potential for organic nitrogen ammonification, aerobic nitrification, anaerobic nitrate reduction and anaerobic ammonium oxidation (anammox) at this landfilling site. Seasonal samples from leachate collection treatment ponds were used as an inoculum to feed synthetic media to determine potential rates of nitrogen transformations. Aerobic ammonium oxidation potential (<0.06 mg N L{sup -1} h{sup -1}) was more than a hundred times lower than the anaerobic nitrogen transformation processes and organic nitrogen ammonification, which were of the same order of magnitude. Anaerobic nitrate oxidation did not proceed beyond nitrite; isolates grown with nitrate as electron acceptor did not degrade nitrite further. Effects of season were only observed for aerobic nitrification and anammox, and were relatively minor: rates were up to three times higher in the dry season. To completely remove the excess ammonium from the leachate, we propose a two-stage treatment system to be implemented. Aeration in the first leachate pond would strongly contribute to aerobic ammonium oxidation to nitrate by providing the currently missing oxygen in the anaerobic

  17. Recycling of aged refuse from a closed landfill.

    PubMed

    Zhao, Youcai; Song, Liyan; Huang, Renhua; Song, Lijie; Li, Xiong

    2007-04-01

    In this study, refuse excavated from a typical refuse landfill in Shanghai after 8-10 years of placement was characterized in terms of particle size, total nitrogen, total phosphorus, and biodegradable matter. The refuse contained a large and diverse population of micro-organisms with a high capacity for decomposing refractory organic matter present in some wastewaters, including leachate. It was found that the aged refuse was quite stable after about a decade of decomposition in the warm, humid climate of southern China. The fine fractions resembled and had the properties of black soil, a medium that is suitable for green construction, organic fertilizer, or as bioreactor media for biological treatment of organic wastewaters. Excavation of the aged refuse would make about 50% of the space available for fresh refuse. The plastics, glass, textiles, and cans can be readily mechanically separated and recycled after cleaning. It is estimated that at least 200 millions tonnes of such aged refuse are available in China alone, and at least 10 times that much is buried worldwide. Hence, the evaluation of mined landfill waste and consideration of its potential uses is of great significance.

  18. Town of Edinburg landfill reclamation demonstration project

    SciTech Connect

    Not Available

    1992-05-15

    Landfill reclamation is the process of excavating a solid waste landfill to recover materials, reduce environmental impacts, restore the land resource, and, in some cases, extend landfill life. Using conventional surface mining techniques and specialized separation equipment, a landfill may be separated into recyclable material, combustible material, a soil/compost fraction and residual waste. A landfill reclamation demonstration project was hosted at the Town of Edinburg municipal landfill in northwest Saratoga County. The report examines various separation techniques employed at the site and appropriate uses for reclaimed materials. Specifications regarding engineered work plans, health and safety monitoring, and contingency preparedness are discussed. Major potential applications and benefits of using landfill reclamation technology at existing landfills are identified and discussed. The research and development aspect of the report also examines optimal screening technologies, site selection protocol and the results of a test burn of reclaimed waste at a waste-to-energy facility. Landfill reclamation costs are developed, and economic comparisons are made between reclamation costs and conventional landfill closure costs, with key criteria identified. The results indicate that, although dependent on site-specific conditions and economic factors, landfill reclamation can be a technically and economically feasible alternative or companion to conventional landfill closure under a range of favorable conditions. Feasibility can be determined only after an investigation of the variety of landfill conditions and reclamation options.

  19. Landfill to Learning Facility

    NASA Astrophysics Data System (ADS)

    Venner, Laura

    2008-05-01

    Engaging "K-to-Gray” audiences (children, families, and older adults) in scientific exploration and discovery is the main goal of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will bring hands-on scientific experiences to the 25,000 students and 3,000 adults that visit our site from the NY/NJ region each year. Our programs adhere to the New Jersey Core Curriculum Content Standards and are modified for accessibility for the underserved communities that visit us, specifically those individuals that have mobility, sensory, and/or cognitive ability differences. The programs are conducted in a classroom setting and are designed to nourish the individual's inquisitive nature and provide an opportunity to function as a scientist by, making observations, performing experiments and recording data. We have an $850,000, three year NSF grant that targets adults with disabilities and older adults with age related limitations in vision, hearing, cognition and/or mobility. From dip netting in the marsh to astronomical investigation of the cosmos, the MEC/CESE remains committed to reaching the largest audience possible and leaving them with a truly exceptional scientific experience that serves to educate and inspire.

  20. Biodegradation of trichloroethylene in continuous-recycle expanded-bed bioreactors

    SciTech Connect

    Phelps, T.J.; Niedzielski, J.J.; Schram, R.M. ); Herbes, S.E.; White, D.C. )

    1990-06-01

    Experimental bioreactors operated as recirculated closed systems were inoculated with bacterial cultures that utilized methane, propane, and tryptone-yeast extract as aerobic carbon and energy sources and degraded trichloroethylene (TCE). Up to 95% removal of TCE was observed after 5 days of incubation. Uninoculated bioreactors inhibited with 0.5% Formalin and 0.2% sodium azide retained greater than 95% of their TCE after 20 days. Each bioreactor consisted of an expanded-bed column through which the liquid phase was recirculated and a gas recharge column which allowed direct headspace sampling. Pulses of TCE (20 mg/liter) were added to bioreactors, and gas chromatography was used to monitor TCE, propane, methane, and carbon dioxide. Pulsed feeding of methane and propane with air resulted in 1 mol of TCE degraded per 55 mol of substrate utilized. Perturbation studies revealed the pH shifts from 7.2 to 7.5 decreased TCE degradation by 85%. The bioreactors recovered to baseline activities within 1 day after the pH returned to neutrality.

  1. Effect of enhanced leachate recirculated (ELR) landfill operation and gas extraction on greenhouse gas emissions

    NASA Astrophysics Data System (ADS)

    Samir, Sonia

    The bioreactor/ enhanced leachate recirculated (ELR) landfill operation with the addition of moisture/ leachate to the landfill, accelerate the process of landfill waste decomposition; and increase the generation of LFG over a shorter period of time. Since emissions from the landfills are directly related to the gas generation, the increase in gas generation might also increase the emission from the landfill. On the contrary, the presence of gas extraction is suggested to mitigate the fugitive emissions from the landfills. Therefore, the motivation of the current study was to evaluate the effect of ELR operation as well as the gas extraction on the greenhouse gas emissions from the landfill. The current study was conducted in the City of Denton Landfill, Texas. Methane emission was investigated using a portable FID and static flux chamber technique from the landfill surface. Emission was measured from an ELR operated cell (cell 2) as well as a conventional cell (cell 0) in the City of Denton Landfill. Methane emission for cell 2 varied from 9544.3 ppm to 0 ppm while for cell 0, it varied from 0 ppm to 47 ppm. High spatial variations were observed during monitoring from both cells 0 and cell 2 which could be recognized as the variation of gas generation below the cover soil. The comparison between emissions from the slope and surface of the landfill showed that more methane emission occurred from the slopes than the top surface. In addition, the average landfill emission showed an increasing trend with increase in temperature and decreasing trend with increasing precipitation. The effect of ELR operation near the recirculation pipes showed a lag period between the recirculation and the maximum emission near the pipe. The emission near the pipe decreased after 1 day of recirculation and after the initial decrease, the emission started to increase and continued to increase up to 7 days after the recirculation. However, approximately after 10 days of recirculation, the

  2. On-line removal of volatile fatty acids from CELSS anaerobic bioreactor via nanofiltration

    NASA Technical Reports Server (NTRS)

    Colon, Guillermo

    1995-01-01

    The CELSS (controlled ecological life support system) resource recovery system, which is a waste processing system, uses aerobic and anaerobic bioreactors to recover plants nutrients and secondary foods from the inedible biomass. The anaerobic degradation of the inedible biomass by means of culture of rumen bacteria,generates organic compounds such as volatile fatty acids (acetic, propionic, butyric, VFA) and ammonia. The presence of VFA in the bioreactor medium at fairly low concentrations decreases the microbial population's metabolic reactions due to end-product inhibition. Technologies to remove VFA continuously from the bioreactor are of high interest. Several candidate technologies were analyzed, such as organic solvent liquid-liquid extraction, adsorption and/or ion exchange, dialysis, electrodialysis, and pressure driven membrane separation processes. The proposed technique for the on-line removal of VFA from the anaerobic bioreactor was a nanofiltration membrane recycle bioreactor. In order to establish the nanofiltration process performance variables before coupling it to the bioreactor, a series of experiments were carried out using a 10,000 MWCO tubular ceramic membrane module. The variables studied were the bioreactor slurry permeation characteristics, such as, the permeate flux, VFA and the nutrient removal rates as a function of applied transmembrane pressure, fluid recirculation velocity, suspended matter concentration, and process operating time. Results indicate that the permeate flux, VFA and nutrients removal rates are directly proportional to the fluid recirculation velocity in the range between 0.6 to 1.0 m/s, applied pressure when these are low than 1.5 bar, and inversely proportional to the total suspended solids concentration in the range between 23,466 to 34,880. At applied pressure higher than 1.5 bar the flux is not more linearly dependent due to concentration polarization and fouling effects over the membrange surface. It was also found

  3. Landfill mining: Giving garbage a second chance

    SciTech Connect

    Cobb, C.C.; Ruckstuhl, K. )

    1988-08-01

    Some communities face the problems of lack of landfill space and lack of landfill cover dirt. In some cases, existing landfills may be mined to reclaim dirt for use as cover material and to recover space for reuse. Such mining also has the potential of recovering recyclables and incinerator fuels. Machinery to reclaim refuse deposits, and their heterogeneous composted ingredients, was successfully tested at two Florida landfills in June 1987. One of the Florida mining tests, at the Collier County landfill near the city of Naples, had goals of demonstrating an economical mechanical system to separate the depository's ingredients into usable or redisposable components, and to see if the method could enable the county to avoid the expenses associated with permanent closure of a full landfill. This paper describes the history of the Collier County landfill, the equipment and feasibility test, economics, the monitoring of odors, landfill gas, and heavy metals, and results of the test.

  4. Landfill mining for resource recovery

    SciTech Connect

    Reith, C.C.

    1997-12-31

    Landfills are repositories of subeconomic resources. Landfill mining is an important enterprise that will someday return these resources to productive use, closing the loop on finite resources and stimulating economic development in communities near landfills. Secondary development of interred resources (landfill waste) will become economically viable as the environmental externalities of primary resource development -- e.g., the destruction of pristine habitat -- are more fully accounted for in programs of ecological design and design for environment. It is important to take an integrated and holistic approach to this new endeavor, which will be a complex assemblage of disciplines. Component disciplines include: resource economics, characterization, and excavation; contaminant control, and protection of environmental safety and health; material sorting, blending, and pretreatment; resource conversion, recovery, storage, and distribution; and reclamation for long-term land use. These technical elements must be addressed in close combination with compelling social issues such as environmental justice that may be especially critical in economically depressed communities surrounding today`s landfills.

  5. Perfluorinated alkyl substances (PFASs) in northern Spain municipal solid waste landfill leachates.

    PubMed

    Fuertes, I; Gómez-Lavín, S; Elizalde, M P; Urtiaga, A

    2017-02-01

    Landfill leachates have been recognized as significant secondary sources of poly- and perfluoroalkyl substances (PFASs). This study presents data on the occurrence and concentration of 11 perfluoroalkyl carboxylates (PFCAs) and 5 perfluoroalkyl sulfonates (PFSAs) in leachates from 4 municipal solid waste landfill sites located across northern Spain. To the best of our knowledge, this is the first report of the presence of PFASs in Spanish landfill leachates. Two of the landfill sites applied on-site treatment using membrane bioreactors (MBR), and its effect on PFASs occurrence is also reported. Total PFASs (∑PFASs) in raw leachates reached 1378.9 ng/L, while in treated samples ∑PFASs was approximately two-fold (3162.3 ng/L). PFCAs accounted for the majority of the detected PFASs and perfluorooctanoic acid (PFOA) was the dominant compound in raw leachates (42.6%), followed by shorter chain PFHxA (30.1%), PFPeA and PFBA. The age of the sites might explain the PFASs pattern found in raw leachates as all of them were stabilized leachates. However, PFASs profile was different in treated samples where the most abundant compound was PFHxA (26.5%), followed by linear perfluorobutane sulfonate (L-PFBS) (18.7%) and PFOA (17.7%). The overall increase of the PFASs content as well as the change in the PFASs profile after the MBR treatment, could be explained by the possible degradation of PFASs precursors such as fluorotelomer alcohols or fluorotelomer sulfonates. Using the volume of leachates generated in the landfill sites, that served 1.8 million people, the discharge of 16 ∑PFASs contained in the landfill leachates was estimated as 1209 g/year.

  6. Degradation of toxaphene in water during anaerobic and aerobic conditions.

    PubMed

    LacayoR, M; van Bavel, B; Mattiasson, B

    2004-08-01

    The degradation of technical toxaphene in water with two kinds of bioreactors operating in sequence was studied. One packed bed reactor was filled with Poraver (foam glass particles) running at anaerobic conditions and one suspended carrier biofilm reactor working aerobically. Chemical oxygen demand (COD), chloride, sulphate, pH, dissolved oxygen, total toxaphene and specific toxaphene isomers were measured. After 6 weeks approx. 87% of the total toxaphene was degraded reaching 98% by week 39. The majority of the conversion took place in the anaerobic reactor. The concentrations of toxaphene isomers with more chlorine substituents decreased more rapidly than for isomers with less chlorine substituents.

  7. Exploring the potential of membrane bioreactors to enhance metals removal from wastewater: pilot experiences.

    PubMed

    Fatone, F; Eusebi, A L; Pavan, P; Battistoni, P

    2008-01-01

    The potential of membrane bioreactors to enhance the removal of selected metals from low loaded sewages has been explored. A 1400 litre pilot plant, equipped with an industrial submerged module of hollow fibre membranes, has been used in three different configurations: membrane bioreactor, operating in sequencing batch modality, for the treatment of real mixed municipal/industrial wastewater; membrane-assisted biosorption reactor, for the treatment of real leachate from municipal landfills; continuously fed membrane bioreactor, for the treatment of water charged with cadmium and nickel ions. The results show that: (a) in treating wastewaters with low levels of heavy metals (< one milligram per litre concentration), operating high sludge ages is not an effective strategy to significantly enhance the metals removal; (b) Hg and Cd are effectively removed already in conventional systems with gravitational final clarifiers, while Cu, Cr, Ni can rely on a additional performance in membrane bioreactors; (c) the further membrane effect is remarkable for Cu and Cr, while it is less significant for Ni. Basically, similar membrane effects recur in three different experimental applications that let us estimate the potential of membrane system to retain selected metal complexes. The future development of the research will investigate the relations between the membrane effect and the manipulable filtration parameters (i.e., permeate flux, solids content, filtration cycle).

  8. What Is Aerobic Dancing?

    MedlinePlus

    ... aerobics can reach up to six times the force of gravity, which is transmitted to each of the 26 bones in the foot. Because of the many side-to-side motions, shoes need an arch design that will compensate ...

  9. APPROACH FOR ESTIMATING GLOBAL LANDFILL METHANE EMISSIONS

    EPA Science Inventory

    The report is an overview of available country-specific data and modeling approaches for estimating global landfill methane. Current estimates of global landfill methane indicate that landfills account for between 4 and 15% of the global methane budget. The report describes an ap...

  10. Mining landfills for space and fuel

    SciTech Connect

    Flosdorf, H.W.; Alexieff, S.

    1993-03-01

    Lancaster County, Pennsylvania`s experiments with landfill reclamation are helping the county remain self-sufficient in managing its solid waste stream. Landfill mining is proving to be a worthwhile approach to extending landfill life and obtaining fuel for the county`s waste-to-energy plant.

  11. METHANE PHYTOREMEDIATION BY VEGETATIVE LANDFILL COVER SYSTEMS

    EPA Science Inventory

    Landfill gas, consisting of methane and other gases, is produced from organic compounds degrading in landfills, contributes to global climate change, is toxic to various types of vegetation, and may pose a combustion hazard at higher concentrations. New landfills are required to ...

  12. Treatment of landfill leachate using ASBR combined with zeolite adsorption technology.

    PubMed

    Lim, Chi Kim; Seow, Ta Wee; Neoh, Chin Hong; Md Nor, Muhamad Hanif; Ibrahim, Zaharah; Ware, Ismail; Mat Sarip, Siti Hajar

    2016-12-01

    Sanitary landfilling is the most common way to dispose solid urban waste; however, improper landfill management may pose serious environmental threats through discharge of high strength polluted wastewater also known as leachate. The treatment of landfill leachate to fully reduce the negative impact on the environment, is nowadays a challenge. In this study, an aerobic sequencing batch reactor (ASBR) was proposed for the treatment of locally obtained real landfill leachate with initial ammoniacal nitrogen and chemical oxygen demand (COD) concentration of 1800 and 3200 mg/L, respectively. ASBR could remove 65 % of ammoniacal nitrogen and 30 % of COD during seven days of treatment time. Thereafter, an effective adsorbent, i.e., zeolite was used as a secondary treatment step for polishing the ammoniacal nitrogen and COD content that is present in leachate. The results obtained are promising where the adsorption of leachate by zeolite further enhanced the removal of ammoniacal nitrogen and COD up to 96 and 43 %, respectively. Furthermore, this combined biological-physical treatment system was able to remove heavy metals, i.e. aluminium, vanadium, chromium, magnesium, cuprum and plumbum significantly. These results demonstrate that combined ASBR and zeolite adsorption is a feasible technique for the treatment of landfill leachate, even considering this effluent's high resistance to treatment.

  13. Evaluation of the Treatment Process of Landfill Leachate Using the Toxicity Assessment Method

    PubMed Central

    Qiu, Aifeng; Cai, Qiang; Zhao, Yuan; Guo, Yingqing; Zhao, Liqian

    2016-01-01

    Landfill leachate is composed of a complex composition with strong biological toxicity. The combined treatment process of coagulation and sedimentation, anaerobics, electrolysis, and aerobics was set up to treat landfill leachate. This paper explores the effect of different operational parameters of coagulation and sedimentation tanks and electrolytic cells, while investigating the combined process for the removal efficiency of physicochemical indices after processing the landfill leachate. Meanwhile, a battery of toxicity tests with Vibrio fischeri, zebrafish larvae, and embryos were conducted to evaluate acute toxicity and calculated the toxicity reduction efficiency after each treatment process. The combined treatment process resulted in a 100% removal efficiency of Cu, Cd and Zn, and a 93.50% and an 87.44% removal efficiency of Ni and Cr, respectively. The overall removal efficiency of chemical oxygen demand (COD), ammonium nitrogen (NH4+-N), and total nitrogen (TN) were 93.57%, 97.46% and 73.60%, respectively. In addition, toxicity test results showed that the acute toxicity of landfill leachate had also been reduced significantly: toxicity units (TU) decreased from 84.75 to 12.00 for zebrafish larvae, from 82.64 to 10.55 for zebrafish embryos, and from 3.41 to 0.63 for Vibrio fischeri. The combined treatment process was proved to be an efficient treatment method to remove heavy metals, COD, NH4+-N, and acute bio-toxicity of landfill leachate. PMID:28009808

  14. Astronomy on a Landfill

    NASA Astrophysics Data System (ADS)

    Venner, Laura

    2008-09-01

    Engaging "K-to-Gray” audiences (children, families, and older adults) in astronomical activities is one of the main goals of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of IYA 2009 to the approximately 25,000 students and 15,000 adults that visit our site from the NY/NJ region each year. Diversifying our traditional environmental science offerings, we have incorporated astronomy into our repertoire with "The Sun Through Time” module, which includes storytelling, cultural astronomy, telescope anatomy, and other activities that are based on the electromagnetic spectrum and our current knowledge of the sun. These lessons have also been modified to bring astronomy to underserved communities, specifically those individuals that have dexterity or cognitive ability differences. The program is conducted in a classroom setting and is designed to meet New Jersey Core Curriculum Content Standards. With the installation of our new 20” telescope, students and amateur astronomers will be given the opportunity to perform rudimentary research. In addition, a program is in development that will allow individuals to measure local sky brightness and understand the effects of light pollution on astronomical viewing. Teaching astronomy in an urban setting presents many challenges. All individuals, regardless of ability level or location, should be given the opportunity to be exposed to the wonders of the universe and the MEC/CESE has been successful in providing those opportunities.

  15. Astronomy on a Landfill

    NASA Astrophysics Data System (ADS)

    Venner, Laura

    2008-05-01

    Engaging "K-to-Gray” audiences (children, families, and older adults) in astronomical activities is one of the main goals of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of IYA 2009 to the approximately 25,000 students and 3,000 adults that visit our site from the NY/NJ region each year. Diversifying our traditional environmental science offerings, we have incorporated astronomy into our repertoire with "The Sun Through Time” module, which includes storytelling, cultural astronomy, telescope anatomy, and other activities that are based on the electromagnetic spectrum and our current knowledge of the sun. These lessons have also been modified to bring astronomy to underserved communities, specifically those individuals that have dexterity or cognitive ability differences. The program is conducted in a classroom setting and is designed to meet New Jersey Core Curriculum Content Standards. With the installation of our new 20” telescope, students and amateur astronomers will be given the opportunity to perform rudimentary research. In addition, a program is in development that will allow individuals to measure local sky brightness and understand the effects of light pollution on astronomical viewing. Teaching astronomy in an urban setting presents many challenges. All individuals, regardless of ability level or location, should be given the opportunity to be exposed to the wonders of the universe and the MEC/CESE has been successful in providing those opportunities.

  16. Geosynthetics conquer the landfill law

    SciTech Connect

    Derian, L.; Gharios, K.M. . Solid Waste Management Div.); Kavazanjian, E. Jr.; Snow, M.S. )

    1993-12-01

    Los Angeles' last operating landfill is undergoing a 4 million m[sup 3] expansion using innovative materials in the liner system to overcome difficult site conditions. The design represents the first approved alternative in California -- and perhaps in the nation -- to the Resource Conservation and Recovery Act's Subtitle D regulations for liner systems. This article examines the regulatory journey that led to approval and the liner's design and construction. Steep slopes at Los Angeles' only operating municipal solid-waste landfill (MSW) forced designers to use an innovative geosynthetic liner and leachate collection system. Its use sets a precedent for alternatives to the prescriptive regulations for liner systems present in Subtitle D of the Resource and Conservation Recovery Act (RCRA). To provide uninterrupted service at the landfill, design and construction proceeded concurrently with regulatory approval.

  17. Sustainable treatment of landfill leachate

    NASA Astrophysics Data System (ADS)

    Kamaruddin, Mohamad Anuar; Yusoff, Mohd. Suffian; Aziz, Hamidi Abdul; Hung, Yung-Tse

    2015-06-01

    Landfill leachate is a complex liquid that contains excessive concentrations of biodegradable and non-biodegradable products including organic matter, phenols, ammonia nitrogen, phosphate, heavy metals, and sulfide. If not properly treated and safely disposed, landfill leachate could be an impending source to surface and ground water contamination as it may percolate throughout soils and subsoils, causing adverse impacts to receiving waters. Lately, various types of treatment methods have been proposed to alleviate the risks of untreated leachate. However, some of the available techniques remain complicated, expensive and generally require definite adaptation during process. In this article, a review of literature reported from 2008 to 2012 on sustainable landfill leachate treatment technologies is discussed which includes biological and physical-chemical techniques, respectively.

  18. Leaching of brominated flame retardants from mixed wastes in lysimeters under conditions simulating landfills in developing countries.

    PubMed

    Kajiwara, Natsuko; Hirata, Osamu; Takigami, Hidetaka; Noma, Yukio; Tachifuji, Ayako; Matsufuji, Yasushi

    2014-12-01

    In developing countries, wastes are usually not separated before being disposed of in solid-waste landfills, most of which are open dumps without adequate measures to prevent environmental pollution. To understand the leaching behavior of brominated flame retardants (BFRs) from waste consumer products in landfills, we have been conducting a long-term landfill lysimeter experiment since 2006 under conditions designed to mimic three types of landfill conditions in developing countries: aerobic, semi-aerobic, and anaerobic. Pilot-scale lysimeters (60-cm i.d.) were filled with a 400-cm layer of mixed wastes consisting of 35 wt% food, 20 wt% paper, 20 wt% paper pulp, 13 wt% plastic, 10 wt% wood chips, 1 wt% glass, and 1 wt% metals, proportions that are typical of unsorted municipal solid waste in Asian developing countries. In the present study, we determined the concentrations of polybrominated diphenyl ethers, tetrabromobisphenol A, tribromophenols, and hexabromocyclododecanes in leachate samples collected from the lysimeters during the first 3.5 years of the experiment, to evaluate BFR elution behavior in early-stage landfills. Under all three conditions, BFR elution started at the beginning of the experiment. The BFR concentrations in the leachates from the aerobic lysimeter tended to be lower than those from the anaerobic lysimeter, suggesting that the presence of air inside landfills considerably reduces BFR elution to the surrounding environment. During the 3.5-year experiment, BFR outflow from the lysimeters was only 0.001-0.58% of the total BFRs in the loaded waste; that is, most of the BFRs in the waste remained in the lysimeters.

  19. Tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Cells from kidneys lose some of their special features in conventional culture but form spheres replete with specialized cell microvilli (hair) and synthesize hormones that may be clinically useful. Ground-based research studies have demonstrated that both normal and neoplastic cells and tissues recreate many of the characteristics in the NASA bioreactor that they display in vivo. Proximal kidney tubule cells that normally have rich apically oriented microvilli with intercellular clefts in the kidney do not form any of these structures in conventional two-dimensional monolayer culture. However, when normal proximal renal tubule cells are cultured in three-dimensions in the bioreactor, both the microvilli and the intercellular clefts form. This is important because, when the morphology is recreated, the function is more likely also to be rejuvenated. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  20. Photoacoustic infrared spectroscopy for conducting gas tracer tests and measuring water saturations in landfills

    SciTech Connect

    Jung, Yoojin; Han, Byunghyun; Mostafid, M. Erfan; Chiu, Pei; Yazdani, Ramin; Imhoff, Paul T.

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Photoacoustic infrared spectroscopy tested for measuring tracer gas in landfills. Black-Right-Pointing-Pointer Measurement errors for tracer gases were 1-3% in landfill gas. Black-Right-Pointing-Pointer Background signals from landfill gas result in elevated limits of detection. Black-Right-Pointing-Pointer Technique is much less expensive and easier to use than GC. - Abstract: Gas tracer tests can be used to determine gas flow patterns within landfills, quantify volatile contaminant residence time, and measure water within refuse. While gas chromatography (GC) has been traditionally used to analyze gas tracers in refuse, photoacoustic spectroscopy (PAS) might allow real-time measurements with reduced personnel costs and greater mobility and ease of use. Laboratory and field experiments were conducted to evaluate the efficacy of PAS for conducting gas tracer tests in landfills. Two tracer gases, difluoromethane (DFM) and sulfur hexafluoride (SF{sub 6}), were measured with a commercial PAS instrument. Relative measurement errors were invariant with tracer concentration but influenced by background gas: errors were 1-3% in landfill gas but 4-5% in air. Two partitioning gas tracer tests were conducted in an aerobic landfill, and limits of detection (LODs) were 3-4 times larger for DFM with PAS versus GC due to temporal changes in background signals. While higher LODs can be compensated by injecting larger tracer mass, changes in background signals increased the uncertainty in measured water saturations by up to 25% over comparable GC methods. PAS has distinct advantages over GC with respect to personnel costs and ease of use, although for field applications GC analyses of select samples are recommended to quantify instrument interferences.

  1. Acclimation of aerobic-activated sludge degrading benzene derivatives and co-metabolic degradation activities of trichloroethylene by benzene derivative-grown aerobic sludge.

    PubMed

    Wang, Shizong; Yang, Qi; Bai, Zhiyong; Wang, Shidong; Wang, Yeyao; Nowak, Karolina M

    2015-01-01

    The acclimation of aerobic-activated sludge for degradation of benzene derivatives was investigated in batch experiments. Phenol, benzoic acid, toluene, aniline and chlorobenzene were concurrently added to five different bioreactors which contained the aerobic-activated sludge. After the acclimation process ended, the acclimated phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic-activated sludge were used to explore the co-metabolic degradation activities of trichloroethylene (TCE). Monod equation was employed to simulate the kinetics of co-metabolic degradation of TCE by benzene derivative-grown sludge. At the end of experiments, the mixed microbial communities grown under different conditions were identified. The results showed that the acclimation periods of microorganisms for different benzene derivatives varied. The maximum degradation rates of TCE for phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic sludge were 0.020, 0.017, 0.016, 0.0089 and 0.0047 mg g SS(-1) h(-1), respectively. The kinetic of TCE degradation in the absence of benzene derivative followed Monod equation well. Also, eight phyla were observed in the acclimated benzene derivative-grown aerobic sludge. Each of benzene derivative-grown aerobic sludge had different microbial community composition. This study can hopefully add new knowledge to the area of TCE co-metabolic by mixed microbial communities, and further the understanding on the function and applicability of aerobic-activated sludge.

  2. Landfill Liners and Covers: Properties and Application to Army Landfills.

    DTIC Science & Technology

    1984-06-01

    sands and gravels were used for cover material. Several moni- toring points placed through and around the landfill defined the area of groundwater ... pollution . 2 1H. Dratfield and L. Mavtone, personal communication. 53 0 O GAS VENT 2’ FINAL COVER TREATMENT NEW- LAGOON W LT WAT _ LEACHATE COLLECTION

  3. Comparison of biomass from integrated fixed-film activated sludge (IFAS), moving bed biofilm reactor (MBBR) and membrane bioreactor (MBR) treating recalcitrant organics: Importance of attached biomass.

    PubMed

    Huang, Chunkai; Shi, Yijing; Xue, Jinkai; Zhang, Yanyan; Gamal El-Din, Mohamed; Liu, Yang

    2017-03-15

    This study compared microbial characteristics and oil sands process-affected water (OSPW) treatment performance of five types of microbial biomass (MBBR-biofilm, IFAS-biofilm, IFAS-floc, MBR-aerobic-floc, and MBR-anoxic-floc) cultivated from three types of bioreactors (MBBR, IFAS, and MBR) in batch experiments. Chemical oxygen demand (COD), ammonium, acid extractable fraction (AEF), and naphthenic acids (NAs) removals efficiencies were distinctly different between suspended and attached bacterial aggregates and between aerobic and anoxic suspended flocs. MBR-aerobic-floc and MBR-anoxic-floc demonstrated COD removal efficiencies higher than microbial aggregates obtained from MBBR and IFAS, MBBR and IFAS biofilm had higher AEF removal efficiencies than those obtained using flocs. MBBR-biofilm demonstrated the most efficient NAs removal from OSPW. NAs degradation efficiency was highly dependent on the carbon number and NA cyclization number according to UPLC/HRMS analysis. Mono- and di-oxidized NAs were the dominant oxy-NA species in OSPW samples. Microbial analysis with quantitative polymerase chain reaction (q-PCR) indicated that the bacterial 16S rRNA gene abundance was significantly higher in the batch bioreactors with suspended flocs than in those with biofilm, the NSR gene abundance in the MBR-anoxic bioreactor was significantly lower than that in aerobic batch bioreactors, and denitrifiers were more abundant in the suspended phase of the activated sludge flocs.

  4. Landfill gas cleanup for fuel cells

    SciTech Connect

    1995-08-01

    EPRI is to test the feasibility of using a carbonate fuel cell to generate electricity from landfill gas. Landfills produce a substantial quantity of methane gas, a natural by-product of decaying organic wastes. Landfill gas, however, contains sulfur and halogen compounds, which are known contaminants to fuel cells and their fuel processing equipment. The objective of this project is to clean the landfill gas well enough to be used by the fuel cell without making the process prohibitively expensive. The cleanup system tested in this effort could also be adapted for use with other fuel cells (e.g., solid oxide, phosphoric acid) running on landfill gas.

  5. Landfill reclamation attracts attention and questions

    SciTech Connect

    Aquino, J.T.

    1994-12-01

    Landfill mining or reclamation has fit neatly into the recycling/reuse mindset. In heralding the first California landfill reclamation project at the Caspar Landfill municipal solid waste (MSW) site in May 1994, a California state official described it as ''win-win. Nobody loses''. Speaking at a session at the annual meeting of the Solid Waste Management Association of North America (SWANA), held August 2--6, 1994, Joanne R. Guerriero, senior project engineer, Malcolm Pirnie, Inc. (White Plains, NY), said landfill reclamation--the excavation of a landfill using conventional mining technology to recover and reuse resources--can: extend the life of existing landfill sites and reduce the need for siting new landfills; decrease the area requiring closure; remediate an environmental concern by removing a contaminant source; reclaim marketable recyclables; and capture energy through waste combustion.

  6. Monitoring Methanotrophic Bacteria in Hybrid Anaerobic-Aerobic Reactors with PCR and a Catabolic Gene Probe

    PubMed Central

    Miguez, Carlos B.; Shen, Chun F.; Bourque, Denis; Guiot, Serge R.; Groleau, Denis

    1999-01-01

    We attempted to mimic in small upflow anaerobic sludge bed (UASB) bioreactors the metabolic association found in nature between methanogens and methanotrophs. UASB bioreactors were inoculated with pure cultures of methanotrophs, and the bioreactors were operated by using continuous low-level oxygenation in order to favor growth and/or survival of methanotrophs. Unlike the reactors in other similar studies, the hybrid anaerobic-aerobic bioreactors which we used were operated synchronously, not sequentially. Here, emphasis was placed on monitoring various methanotrophic populations by using classical methods and also a PCR amplification assay based on the mmoX gene fragment of the soluble methane monooxygenase (sMMO). The following results were obtained: (i) under the conditions used, Methylosinus sporium appeared to survive better than Methylosinus trichosporium; (ii) the PCR method which we used could detect as few as about 2,000 sMMO gene-containing methanotrophs per g (wet weight) of granular sludge; (iii) inoculation of the bioreactors with pure cultures of methanotrophs contributed greatly to increases in the sMMO-containing population (although the sMMO-containing population decreased gradually with time, at the end of an experiment it was always at least 2 logs larger than the initial population before inoculation); (iv) in general, there was a good correlation between populations with the sMMO gene and populations that exhibited sMMO activity; and (v) inoculation with sMMO-positive cultures helped increase significantly the proportion of sMMO-positive methanotrophs in reactors, even after several weeks of operation under various regimes. At some point, anaerobic-aerobic bioreactors like those described here might be used for biodegradation of various chlorinated pollutants. PMID:9925557

  7. Identification of Cellulose Breaking Bacteria in Landfill Samples for Organic Waste Management

    NASA Astrophysics Data System (ADS)

    Chan, P. M.; Leung, F. C.

    2015-12-01

    According to the Hong Kong Environmental Protection Department, the citizens of Hong Kong disposes 13,500 tonnes of waste to the landfill everyday. Out of the 13,500 tonnes, 3600 tonnes consist of organic waste. Furthermore, due to the limited supply of land for landfills in Hong Kong, it is estimated that landfills will be full by about 2020. Currently, organic wastes at landfills undergo anaerobic respiration, where methane gas, one of the most harmful green house gases, will be released. The management of such waste is a pressing issue, as possible solutions must be presented in this crucial period of time. The Independent Schools Foundation Academy introduced their very own method to manage the waste produced by the students. With an approximate of 1500 students on campus, the school produces 27 metric tonnes of food waste each academic year. The installation of the rocket food composter provides an alternate method of disposable of organic waste the school produces, for the aerobic environment allows for different by-products to be produced, namely compost that can be used for organic farming by the primary school students and subsequently carbon dioxide, a less harmful greenhouse gas. This research is an extension on the current work, as another natural factor is considered. It evaluates the microorganism community present in leachate samples collected from the North East New Territories Landfill, for the bacteria in the area exhibits special characteristics in the process of decomposition. Through the sequencing and analysis of the genome of the bacteria, the identification of the bacteria might lead to a break through on the current issue. Some bacteria demonstrate the ability to degrade lignin cellulose, or assist in the production of methane gas in aerobic respirations. These characteristics can hopefully be utilized in the future in waste managements across the globe.

  8. Attenuation of Landfill Leachate In Unsaturated Sandstone

    NASA Astrophysics Data System (ADS)

    Butler, A. P.; Brook, C.; Godley, A.; Lewin, K.; Young, C. P.

    aerobic. This change appears to be related to the introduction of a landfill gas extraction system at the site, which has resulted in atmospheric oxygen being drawn into the underlying environment. Although the sandstone is relatively inert (CEC around 2 meq.100g-1), a clear retardation of the ammoniacal nitrogen is evident. The retardation coefficient is about 4 giving a linear equilibrium partition factor Kd of 0.15 cm3.g-1 (which is substantially lower than batch laboratory values of 1.2 ­ 2.0 cm3g-1). In addition, model simulations indicate a degree of attenuation of in ammonium concentrations, although the exact nature of this mechanism is still under investigation. Therefore, an analysis of the most recent results at the Burntstump site, set in the context of the historic data, indicates that the amount of attenuation present in 30 m of unsaturated sandstone is sufficient to mitigate most of the impact of MSW leachate emanating from a moderately wet landfill on the underlying groundwater. This has important implications both in terms of groundwater protection and the environmental liabilities for waste operators/site holders at similar sites.

  9. Greenhouse gas emissions from landfill leachate treatment plants: A comparison of young and aged landfill

    SciTech Connect

    Wang, Xiaojun; Jia, Mingsheng; Chen, Xiaohai; Xu, Ying; Lin, Xiangyu; Kao, Chih Ming; Chen, Shaohua

    2014-07-15

    Highlights: • Young and aged leachate works accounted for 89.1% and 10.9% of 33.35 Gg CO{sub 2} yr{sup −1}. • Fresh leachate owned extremely low ORP and high organic matter content. • Strong CH{sub 4} emissions occurred in the fresh leachate ponds, but small in the aged. • N{sub 2}O emissions became dominant in the treatment units of both systems. • 8.45–11.9% of nitrogen was removed as the form of N{sub 2}O under steady-state. - Abstract: With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH{sub 4} emissions were observed from the fresh leachate storage pond, with the fluxes values (2219–26,489 mg C m{sup −2} h{sup −1}) extremely higher than those of N{sub 2}O (0.028–0.41 mg N m{sup −2} h{sup −1}). In contrast, the emission values for both CH{sub 4} and N{sub 2}O were low for the aged leachate tank. N{sub 2}O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8–12% of the removal of N-species gases. Per capita, the N{sub 2}O emission based on both leachate treatment systems was estimated to be 7.99 g N{sub 2}O–N capita{sup −1} yr{sup −1}. An increase of 80% in N{sub 2}O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO{sub 2}, with a small portion as CH{sub 4} (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO{sub 2} eq yr{sup −1}, respectively, for a total that could be transformed to 9.09 kg CO{sub 2} eq capita{sup −1} yr{sup −1}.

  10. Is biodegradability a desirable attribute for discarded solid waste? Perspectives from a national landfill greenhouse gas inventory model.

    PubMed

    Levis, James W; Barlaz, Morton A

    2011-07-01

    There is increasing interest in the use of biodegradable materials because they are believed to be "greener". In a landfill, these materials degrade anaerobically to form methane and carbon dioxide. The fraction of the methane that is collected can be utilized as an energy source and the fraction of the biogenic carbon that does not decompose is stored in the landfill. A landfill life-cycle model was developed to represent the behavior of MSW components and new materials disposed in a landfill representative of the U.S. average with respect to gas collection and utilization over a range of environmental conditions (i.e., arid, moderate wet, and bioreactor). The behavior of materials that biodegrade at relatively fast (food waste), medium (biodegradable polymer) and slow (newsprint and office paper) rates was studied. Poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) (PHBO) was selected as illustrative for an emerging biodegradable polymer. Global warming potentials (GWP) of 26, 720, -1000, 990, and 1300 kg CO(2)e wet Mg(-1) were estimated for MSW, food waste, newsprint, office paper, and PHBO, respectively in a national average landfill. In a state-of-the-art landfill with gas collection and electricity generation, GWP's of -250, 330, -1400, -96, and -420 kg CO(2)e wet Mg(-1) were estimated for MSW, food waste, newsprint, office paper and PHBO, respectively. Additional simulations showed that for a hypothetical material, a slower biodegradation rate and a lower extent of biodegradation improve the environmental performance of a material in a landfill representative of national average conditions.

  11. Energy conservation and production in a packed-bed anaerobic bioreactor

    SciTech Connect

    Pit, W.W. Jr.; Genung, R.K.

    1980-01-01

    Oak Ridge National Laboratory (ORNL) is developing an energy-conserving/ producing wastewater treatment system based on a fixed-film anaerobic bioreactor. The treatment process is based on passing wastewaters upward through the bioreactor for continuous treatment by gravitational settling, biophysical filtration and biological decomposition. A two-year pilot-plant project using a bioreactor designed to treat 5000 gpd has been conducted using raw wastewater on a municipal site in Oak Ridge, Tennessee. Data obtained for the performance of the bioreactor during this project have been analyzed by ORNL and Associated Water and Air Resources Engineers (AWARE), Inc. of Nashville, Tennessee. From these analyses it was estimated that hydraulic loading rates of 0.25 gpm/ft/sup 2/ and hydraulic residence times of 10 hours could be used in designing such bioreactors for the secondary treatment of municipal wastewaters. Conceptual designs for total treatment systems processing up to one million gallons of wastewater per day were developed based on the performance of the pilot plant bioreactor. These systems were compared to activated sludge treatment systems also operating under secondary treatment requirements and were found to consume as little as 30% of the energy required by the activated sludge systems. Economic advantages of the process result from the elimination of operating energy requirements associated with the aeration of aerobic-based processes and with the significant decrease of sludge-handling costs required with conventional activated sludge treatment systems.Furthermore, methane produced by anaerobic fermentation processes occurring during the biological decomposition of carbonaceous wastes also represented a significant and recoverable energy production. For dilute municipal wastewaters this would completely offset the remaining energy required for treatment, while for concentrated industrial wastewater would result in a net production of energy.

  12. A PRELIMINARY EXPERIMENT ON DENITRIFICATION OF WASTE LANDFILL LEACHATE

    NASA Astrophysics Data System (ADS)

    Wada, Nariaki; Nakamichi, Tamihiro; Yagi, Masahiro; Matsumoto, Toshihide; Kugimiya, Akikazu; Michioku, Kohji

    A laboratory experiment on denitrification was carried out in order to reduce nitrogen load from municipal landfill leachate. Nitrogen was efficiently removed by feeding sludge of the leachate pond into the tanks, which could activate denitrification bacteria. Although inorganic reducing agent such as iron powder was not able to make the whole water mass anoxic, denitrification took place by supplying organic matters such as methanol, hydrogen feeding agent, etc.. It is considered that small amount of anoxic water film produced on surfaces of container and carriers might contribute to denitrification, although the bulk water is kept aerobic. It is found that organic matters contained in the leachate is so insufficient that nitrification liquid circulation does not work well for denitrification.

  13. Improvement of biological nitrogen removal with nitrate-dependent Fe(II) oxidation bacterium Aquabacterium parvum B6 in an up-flow bioreactor for wastewater treatment.

    PubMed

    Zhang, Xiaoxin; Li, Ang; Szewzyk, Ulrich; Ma, Fang

    2016-11-01

    Aquabacterium parvum strain B6 exhibited efficient nitrate-dependent Fe(II) oxidation ability using nitrate as an electron acceptor. A continuous up-flow bioreactor that included an aerobic and an anoxic section was constructed, and strain B6 was added to the bioreactor as inocula to explore the application of microbial nitrate-dependent Fe(II) oxidizing (NDFO) efficiency in wastewater treatment. The maximum NRE (anoxic section) and TNRE of 46.9% and 79.7%, respectively, could be obtained at a C/N ratio of 5.3:1 in the influent with HRT of 17. Meanwhile, the taxonomy composition of the reactor was assessed, as well. The NDFO metabolism of strain B6 could be expected because of its relatively dominant position in the anoxic section, whereas potential heterotrophic nitrification and aerobic denitrification developed into the prevailing status in the aerobic section after 50days of continuous operation.

  14. Landfill reduction experience in The Netherlands.

    PubMed

    Scharff, Heijo

    2014-11-01

    Modern waste legislation aims at resource efficiency and landfill reduction. This paper analyses more than 20 years of landfill reduction in the Netherlands. The combination of landfill regulations, landfill tax and landfill bans resulted in the desired landfill reduction, but also had negative effects. A fierce competition developed over the remaining waste to be landfilled. In 2013 the Dutch landfill industry generated €40 million of annual revenue, had €58 million annual costs and therefore incurred an annual loss of €18 million. It is not an attractive option to prematurely end business. There is a risk that Dutch landfill operators will not be able to fulfil the financial obligations for closure and aftercare. Contrary to the polluter pays principle the burden may end up with society. EU regulations prohibiting export of waste for disposal are in place. Strong differentials in landfill tax rate between nations have nevertheless resulted in transboundary shipment of waste and in non-compliance with the self-sufficiency and proximity principles. During the transformation from a disposal society to a recycling society, it is important to carefully plan required capacity and to guide the reorganisation of the landfill sector. At some point, it is no longer profitable to provide landfill services. It may be necessary for public organisations or the state to take responsibility for the continued operation of a 'safety net' in waste management. Regulations have created a financial incentive to pass on the burden of monitoring and controlling the impact of waste to future generations. To prevent this, it is necessary to revise regulations on aftercare and create incentives to actively stabilise landfills.

  15. Dance--Aerobic and Anaerobic.

    ERIC Educational Resources Information Center

    Cohen, Arlette

    1984-01-01

    This article defines and explains aerobic exercise and its effects on the cardiovascular system. Various studies on dancers are cited indicating that dance is an anaerobic activity with some small degree of aerobic benefit. (DF)

  16. Construction and evaluation of simulated pilot scale landfill lysimeter in Bangladesh.

    PubMed

    Rafizul, Islam M; Howlader, Milon Kanti; Alamgir, Muhammed

    2012-11-01

    This research concentrates the design, construction and evaluation of simulated pilot scale landfill lysimeter at KUET campus, Khulna, Bangladesh. Both the aerobic and anaerobic conditions having a base liner and two different types of cap liner were simulated. After the design of a reference cell, the construction of landfill lysimeter was started in January 2008 and completed in July 2008. In all construction process locally available civil construction materials were used. The municipal solid waste (MSW) of 2800-2985 kg having the total volume of 2.80 m(3) (height 1.6 m) and moisture content of 65% was deposited in each lysimeter by applying required compaction energy. In contrast, both the composition in terms of methane (CH(4)), carbon dioxide (CO(2)) and oxygen (O(2)) as well as the flow rate of landfill gas (LFG) generated from MSW in landfill lysimeter were measured and varied significantly in relation to the variation of lysimeter operational condition. Moreover, anaerobic lysimeter-C shows the highest composition of LFG in compare to the anaerobic lysimeter-B due to the providing of lower compaction of cap liner in anaerobic lysimeter-C. Here, it is interesting to note that in absence of compacted clay liner (CCL) and hence percolation of rainwater that facilitates rapid degradation of MSW in aerobic lysimeter-A has resulted in the highest settlement than that of anaerobic landfill lysimeter-B and C. Moreover, in case of anaerobic lysimeter-B and C, the leachate generation was lower than that of aerobic lysimeter-A due to the providing of cap liner in anaerobic lysimeter-B and C, played an important role to reduce the percolation of rainwater. The study also reveals that the leachate pollution index (LPI) has decreased in relation to the increasing of elapsed period as well as the LPI for collection system of aerobic lysimeter-A was higher than that of the collection system of anaerobic lysimeter-B and C. Finally, it can be depicted that LPI for lysimeter

  17. Characterization of organic membrane foulants in a forward osmosis membrane bioreactor treating anaerobic membrane bioreactor effluent.

    PubMed

    Ding, Yi; Tian, Yu; Li, Zhipeng; Liu, Feng; You, Hong

    2014-09-01

    In this study, two aerobic forward osmosis (FO) membrane bioreactors (MBR) were utilized to treat the effluent of mesophilic (35°C) and atmospheric (25°C) anaerobic MBRs, respectively. The results showed that the FO membrane process could significantly improve the removal efficiencies of N and P. Meanwhile, the flux decline of the FOMBR treating effluent of mesophilic AnMBR (M-FOMBR) was higher than that treating effluent of atmospheric AnMBR (P-FOMBR). The organic membrane foulants in the two FOMBRs were analyzed to understand the membrane fouling behavior in FO processes. It was found that the slightly increased accumulation of protein-like substances into external foulants did not cause faster flux decline in P-FOMBR than that in M-FOMBR. However, the quantity of organic matter tended to deposit or adsorb into FO membrane pores in P-FOMBR was less than that in M-FOMBR, which was accordance with the tendency of membrane fouling indicated by flux decline.

  18. Surface emission of landfill gas from solid waste landfill

    NASA Astrophysics Data System (ADS)

    Park, Jin-Won; Shin, Ho-Chul

    The surface emission of landfill gas (LFG) was studied to estimate the amount of LFG efflux from solid waste landfills using an air flux chamber. LFG efflux increased as atmospheric temperature increased during the day, and the same pattern for the surface emission was observed for the change of seasons. LFG efflux rate decreased from summer through winter. The average LFG efflux rates of winter, spring and summer were 0.1584, 0.3013 and 0.8597 m 3 m -2 h -1 respectively. The total amount of surface emission was calculated based on the seasonal LFG efflux rate and the landfill surface area. From the estimates of LFG generation, it is expected that about 30% of the generated LFG may be released through the surface without extraction process. As forced extraction with a blower proceeded, the extraction well pressure decreased from 1100 to -100 mm H 2O, and the LFG surface efflux decreased markedly above 80%. Thus, the utilization of LFG by forced extraction would be the good solution for global warming and air pollution by LFG.

  19. Flux measurements of benzene and toluene from landfill cover soils.

    PubMed

    Tassi, Franco; Montegrossi, Giordano; Vaselli, Orlando; Morandi, Andrea; Capecchiacci, Francesco; Nisi, Barbara

    2011-01-01

    Carbon dioxide and CH(4), C(6)H(6) and C(7)H(8) fluxes from the soil cover of Case Passerini landfill site (Florence, Italy) were measured using the accumulation and static closed chamber methods, respectively. Results show that the CH(4)/CO(2), CH(4)/C(6)H(6) and CH(4)/C(7)H(8) ratios of the flux values are relatively low when compared with those of the 'pristine' biogas produced by degradation processes acting on the solid waste material disposed in the landfill. This suggests that when biogas transits through the cover soil, CH(4) is affected by degradation processes activated by oxidizing bacteria at higher extent than both CO(2) and mono-aromatics. Among the investigated hydrocarbons, C(6)H(6) has shown the highest stability in a wide range of redox conditions. Toluene behaviour only partially resembles that of C(6)H(6), possibly because de-methylation processes require less energy than that necessary for the degradation of C(6)H(6), the latter likely occurring via benzoate at anaerobic conditions and/or through various aerobic metabolic pathways at relatively shallow depth in the cover soil where free oxygen is present. According to these considerations, aromatics are likely to play an important role in the environmental impact of biogas released into the atmosphere from such anthropogenic emission sites, usually only ascribed to CO(2) and CH(4). In this regard, flux measurements using accumulation and static closed chamber methods coupled with gas chromatography and gas chromatography-mass spectrometry analysis may properly be used to obtain a dataset for the estimation of the amount of volatile organic compounds dispersed from landfills.

  20. Effect of Spatial Variations in Temperature, Permeability, and Water Saturation on Partitioning Gas Tracer Tests to Quantify Water in the Vadose Zone and in Landfills

    NASA Astrophysics Data System (ADS)

    Li, L.; Imhoff, P. T.

    2006-12-01

    The measurement of water saturation is important in the vadose zone and in the unsaturated porous media (refuse) in bioreactor landfills. The partitioning gas tracer test (PGTT) has been successfully used to measure water saturations in soils and landfills. However, the effectiveness of the this technique for obtaining average water saturations may depend on spatial variations in temperature (landfills), which result in spatially varying Henry's law constants, as well as spatial variability in water saturations and gas permeability. Investigations of the performance of PGTTs in heterogeneous porous media are needed to assess the utility of this measurement technique in such systems. A two dimensional modeling approach was used to investigate PGTT performance in soils and landfills with spatially varying properties. Temperature, permeability and water saturations were varied spatially to examine their effect on the accuracy of water saturation measurements. The influence of tracer diffusion on PGTT results was also examined. These simulations provide guidelines for applying PGTTs in soils and landfills where spatial variability of properties is significant. Keywords: water saturation, gas tracers, spatial heterogeneity, landfills

  1. Landfill reduction experience in The Netherlands

    SciTech Connect

    Scharff, Heijo

    2014-11-15

    Highlights: • ‘Zero waste’ initiatives never consider risks, side effects or experience of achieved low levels of landfill. • This paper provides insight into what works and what not. • Where strong gradients in regulations and tax occur between countries, waste will find its way to landfills across borders. • Strong landfill reduction can create a fierce competition over the remaining waste to be landfilled resulting in losses. • At some point a public organisation should take responsibility for the operation of a ‘safety net’ in waste management. - Abstract: Modern waste legislation aims at resource efficiency and landfill reduction. This paper analyses more than 20 years of landfill reduction in the Netherlands. The combination of landfill regulations, landfill tax and landfill bans resulted in the desired landfill reduction, but also had negative effects. A fierce competition developed over the remaining waste to be landfilled. In 2013 the Dutch landfill industry generated €40 million of annual revenue, had €58 million annual costs and therefore incurred an annual loss of €18 million. It is not an attractive option to prematurely end business. There is a risk that Dutch landfill operators will not be able to fulfil the financial obligations for closure and aftercare. Contrary to the polluter pays principle the burden may end up with society. EU regulations prohibiting export of waste for disposal are in place. Strong differentials in landfill tax rate between nations have nevertheless resulted in transboundary shipment of waste and in non-compliance with the self-sufficiency and proximity principles. During the transformation from a disposal society to a recycling society, it is important to carefully plan required capacity and to guide the reorganisation of the landfill sector. At some point, it is no longer profitable to provide landfill services. It may be necessary for public organisations or the state to take responsibility for the

  2. Landfill reclamation feasibility study for the Montauk Landfill, town of East Hampton, New York. Final report

    SciTech Connect

    1998-01-01

    A landfill reclamation feasibility study was performed at Montauk Landfill in East Hampton, Long Island, New York. The purpose of the study was to determine whether landfill reclamation is a technically and economically feasible alternative to conventional landfill closure via capping. The technical feasibility of landfill reclamation at the site was determined from a field investigation in which the waste from different periods in the landfill`s history was characterized, the percent of reusable and recyclable materials determined, environmental hazards assessed, and throughput rates determined. Potential markets and/or uses for reclaimed materials were identified and estimates for the re-disposal of the residual waste were obtained from waste-to-energy facilities and offsite landfills.

  3. Use of Fixed-Film Bioreactors, in Situ Microcosms, and Molecular Biological Analyses to Evaluate Bioremediation of Chlorinated Benzenes By Indigenous Bacteria and a Bioaugmented Dechlorinating Consortium

    NASA Astrophysics Data System (ADS)

    Lorah, M. M.; Teunis, J. A.

    2014-12-01

    Evaluation of bioremediation is complicated by contaminant mixtures, high concentrations, variable site conditions, and multiple possible degradation pathways. In this study, fixed-film bioreactor experiments, in situ microcosms, and microbial analyses were utilized to evaluate both anaerobic and aerobic biodegradation processes for tri- and dichlorobenzene isomers, monochlorobenzene, and benzene in a wetland. Biofilm-based bioreactors provide a robust assessment tool because of their typically high degree of stability, even with major and repeated perturbations. Two bioreactor units seeded with an anaerobic dechlorinating consortium (WBC-2) and one unit seeded only with bacteria indigenous to the site were operated under flow-through conditions to compare biougmentation and natural attenuation. Electron donor levels were varied to fluctuate between anaerobic and aerobic conditions, and inflow concentrations of total chlorobenzenes were transitioned from 1-10 mg/L to 50-100 mg/L. Biodegradation resulted in removal efficiencies of 80 to 99 percent for the different compounds and inflow concentrations. Degradation efficiency in the native bioreactor was not impacted by cycling between anaerobic and aerobic conditions, although removal rates for monochlorobenzene and benzene increased under aerobic conditions. In situ microcosms were incubated below the wetland surface in sets of 3 treatments—unamended, biostimulated (lactate addition), and bioaugmented (WBC-2 and lactate). Additional treatment sets contained 13C-labeled contaminants to monitor for production of 13C-containing carbon dioxide and cellular material. Microcosm results verified that WBC-2 bioaugmentation can enhance biodegradation, with complete mineralization of chlorobenzene and benzene in bioaugmented and native treatments. Microbial analyses using QuantArrayTM for functional and taxonomic genes indicated potential for co-occurrence of anaerobic and aerobic biodegradation. Compared to the unamended

  4. The role of forward osmosis and microfiltration in an integrated osmotic-microfiltration membrane bioreactor system.

    PubMed

    Luo, Wenhai; Hai, Faisal I; Kang, Jinguo; Price, William E; Nghiem, Long D; Elimelech, Menachem

    2015-10-01

    This study investigates the performance of an integrated osmotic and microfiltration membrane bioreactor (O/MF-MBR) system for wastewater treatment and reclamation. The O/MF-MBR system simultaneously used microfiltration (MF) and forward osmosis (FO) membranes to extract water from the mixed liquor of an aerobic bioreactor. The MF membrane facilitated the bleeding of dissolved inorganic salts and thus prevented the build-up of salinity in the bioreactor. As a result, sludge production and microbial activity were relatively stable over 60 days of operation. Compared to MF, the FO process produced a better permeate quality in terms of nutrients, total organic carbon, as well as hydrophilic and biologically persistent trace organic chemicals (TrOCs). The high rejection by the FO membrane also led to accumulation of hydrophilic and biologically persistent TrOCs in the bioreactor, consequently increasing their concentration in the MF permeate. On the other hand, hydrophobic and readily biodegradable TrOCs were minimally detected in both MF and FO permeates, with no clear difference in the removal efficiencies between two processes.

  5. Perchlorate and Nitrate Remediation Efficiency and Microbial Diversity in a Containerized Wetland Bioreactor

    SciTech Connect

    Jr., B D; Dibley, V; Pinkart, H; Legler, T

    2004-06-09

    We have developed a method to remove perchlorate (14 to 27 {micro}g/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than two years with a stable ecosystem of indigenous organisms. This study assesses the bioreactor for long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for reduction-oxidation conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chain-reaction products was used to identify dominant microorganisms. Bacteria genera identified were closely affiliated with bacteria widely distributed in soils, mud layers, and fresh water. Of the 17 dominant bands sequenced, most were gram negative and capable of aerobic or anaerobic respiration with nitrate as the terminal electron acceptor (Pseudomonas, Acinetobacter, Halomonas, and Nitrospira). Several identified genera (Rhizobium, Acinetobactor, and Xanthomonas) are capable of fixing atmospheric nitrogen into a combined form (ammonia) usable by host plants. Isolates were identified from the Proteobacteria class, known for the ability to reduce perchlorate. Initial bacterial assessments of sediments confirm the prevalence of facultative anaerobic bacteria capable of reducing perchlorate and nitrate in situ.

  6. Implementation of Aerobic Programs.

    ERIC Educational Resources Information Center

    American Alliance for Health, Physical Education, Recreation and Dance (AAHPERD).

    This information is intended for health professionals interested in implementing aerobic exercise programs in public schools, institutions of higher learning, and business and industry workplaces. The papers are divided into three general sections. The introductory section presents a basis for adhering to a health fitness lifestyle, using…

  7. Aerobic Anoxygenic Phototrophic Bacteria

    PubMed Central

    Yurkov, Vladimir V.; Beatty, J. Thomas

    1998-01-01

    The aerobic anoxygenic phototrophic bacteria are a relatively recently discovered bacterial group. Although taxonomically and phylogenetically heterogeneous, these bacteria share the following distinguishing features: the presence of bacteriochlorophyll a incorporated into reaction center and light-harvesting complexes, low levels of the photosynthetic unit in cells, an abundance of carotenoids, a strong inhibition by light of bacteriochlorophyll synthesis, and the inability to grow photosynthetically under anaerobic conditions. Aerobic anoxygenic phototrophic bacteria are classified in two marine (Erythrobacter and Roseobacter) and six freshwater (Acidiphilium, Erythromicrobium, Erythromonas, Porphyrobacter, Roseococcus, and Sandaracinobacter) genera, which phylogenetically belong to the α-1, α-3, and α-4 subclasses of the class Proteobacteria. Despite this phylogenetic information, the evolution and ancestry of their photosynthetic properties are unclear. We discuss several current proposals for the evolutionary origin of aerobic phototrophic bacteria. The closest phylogenetic relatives of aerobic phototrophic bacteria include facultatively anaerobic purple nonsulfur phototrophic bacteria. Since these two bacterial groups share many properties, yet have significant differences, we compare and contrast their physiology, with an emphasis on morphology and photosynthetic and other metabolic processes. PMID:9729607

  8. Aerobic Dance in Public Schools.

    ERIC Educational Resources Information Center

    Chiles, Barbara Ann; Moore, Suzanne

    1981-01-01

    Aerobic dance offers a challenging workout in a social atmosphere. Though some physical education instructors tend to exclude dance units from the curriculum, most could teach aerobic dance if they had a basic knowledge of aerobic routines. The outline for a unit to be used in the class is presented. (JN)

  9. Pilot-scale comparison of two hybrid-passive landfill leachate treatment systems operated in a cold climate.

    PubMed

    Speer, Sean; Champagne, Pascale; Anderson, Bruce

    2012-01-01

    Hybrid-passive landfill leachate treatment systems employ active pretreatment to remove dissolved inorganic constituents and decrease the oxygen demand of the leachate prior to treatment in a passive system. In a 1-year pilot-scale study, two passive treatment systems - a peat and wood shaving biological trickle filter and a sand and gravel constructed wetland - were installed to treat leachate from the Merrick Landfill in North Bay, Ontario, Canada. Leachate was pretreated in a fixed-film aerobic reactor, which provided reductions in COD (26%), and masses of ammonia (21%), Al (69%), Ca (57%), Fe (73%) and Sr (37%). A comparison of the performance of the hybrid-passive treatment systems indicated different extents of heterotrophic nitrification; the peat and wood shaving filter removed 49% of the ammonia and nitrified 29%, while the constructed wetland removed 99% of the ammonia and nitrified 90%. Hybrid-passive landfill leachate treatment was determined to be feasible in cold climates.

  10. Seismic evaluation of municipal solid waste landfill

    SciTech Connect

    Hovind, C.; Slyh, R.

    1995-12-31

    With the promulgation of the Resource Conservation and Recovery (RCRA) Subtitle D, landfills situated within seismic impact zones must be evaluated for seismic hazards to demonstrate that the containment structures of the landfill can resist the maximum horizontal acceleration in lithified earth materials (bedrock) for the site. If a landfill is sited on saturated soils, it must also be evaluated for liquefaction and lateral spreading. In 1994, EMCON evaluated the seismic hazard for a landfill located along the Columbia River in southwestern Washington. The landfill was founded on dredge fill over natural alluvial deposits. Laboratory testing and state-of-the-art engineering analyses indicated that the sand unit below the landfill had a high potential for liquefaction. The seismic hazard evaluation for the site included a site-specific seismic response analysis, a liquefaction potential analysis, and seismic stability and deformation analysis. The seismic response analysis was conducted for nonliquefied, partially liquefied, and fully liquefied foundation soil conditions. Results are described.

  11. Screening biological methods for laboratory scale stabilization of fine fraction from landfill mining.

    PubMed

    Mönkäre, Tiina J; Palmroth, Marja R T; Rintala, Jukka A

    2017-02-01

    Increasing interest for the landfill mining and the amount of fine fraction (FF) in landfills (40-70% (w/w) of landfill content) mean that sustainable treatment and utilization methods for FF are needed. For this study FF (<20mm) was mined from a municipal solid waste (MSW) landfill operated from 1967 to 1989. FF, which resembles soil, was stabilized in laboratory scale reactors in two phases: first, anaerobically for 101days and second, for 72days using four different methods: anaerobic with the addition of moisture (water) or inoculum (sewage sludge) and aerobic with continuous water washing, with, or without, bulking material. The aim was to evaluate the effect on the stability of mined FF, which has been rarely reported, and to study the quality and quantity of gas and leachate produced during the stabilization experiment. The study showed that aerobic treatment reduced respiration activity (final values 0.9-1.1mgO2/gTS) and residual methane potential (1.1LCH4/kgTS) better than anaerobic methods (1.8-2.3mg O2/g TS and 1.3-2.4L CH4/kg TS, respectively). Bulking material mixed in FF in one aerobic reactor had no effect on the stability of FF. The benefit of anaerobic treatment was the production of methane, which could be utilized as energy. Even though the inoculum addition increased methane production from FF about 30%, but the methane production was still relatively low (in total 1.5-1.7L CH4/kg TS). Continuous water washing was essential to remove leachable organic matter and soluble nutrients from FF, while increasing the volume of leachate collected. In the aerobic treatment, nitrogen was oxidized into nitrite and nitrate and then washed out in the leachate. Both anaerobic and aerobic methods could be used for FF stabilization. The use of FF, in landscaping for example, is possible because its nutrient content (4gN/kg TS and 1g P/kg TS) can increase the nutrient content of soil, but this may have limitations due to the possible presence of heavy metal and

  12. Evaluating leachate recirculation with cellulase addition to enhance waste biostabilisation and landfill gas production.

    PubMed

    Frank, R R; Davies, S; Wagland, S T; Villa, R; Trois, C; Coulon, F

    2016-09-01

    The effect of leachate recirculation with cellulase augmentation on municipal solid waste (MSW) biostabilisation and landfill gas production was investigated using batch bioreactors to determine the optimal conditions of moisture content, temperature and nutrients. Experimentation was thereafter scaled-up in 7L bioreactors. Three conditions were tested including (1) leachate recirculation only, (2) leachate recirculation with enzyme augmentation and (3) no leachate recirculation (control). Cumulative biogas production of the batch tests indicated that there was little difference between the leachate and control test conditions, producing on average 0.043m(3)biogaskg(-1) waste. However the addition of cellulase at 15×10(6)Utonne(-1) waste doubled the biogas production (0.074m(3)biogaskg(-1) waste). Similar trend was observed with the bioreactors. Cellulase addition also resulted in the highest COD reduction in both the waste and the leachate samples (47% and 42% COD reduction, respectively). In both cases, the quantity of biogas produced was closer to the lower value of theoretical and data-based biogas prediction indicators (0.05-0.4m(3)biogaskg(-1) waste). This was likely due to a high concentration of heavy metals present in the leachate, in particular Cr and Mn, which are known to be toxic to methanogens. The cost-benefit analysis (CBA) based on the settings of the study (cellulase concentration of 15×10(6)Utonne(-1) waste) showed that leachate bioaugmentation using cellulase is economically viable, with a net benefit of approximately €12.1million on a 5Mt mixed waste landfill.

  13. Prostate tumor grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This prostate cancer construct was grown during NASA-sponsored bioreactor studies on Earth. Cells are attached to a biodegradable plastic lattice that gives them a head start in growth. Prostate tumor cells are to be grown in a NASA-sponsored Bioreactor experiment aboard the STS-107 Research-1 mission in 2002. Dr. Leland Chung of the University of Virginia is the principal investigator. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and the University of Virginia.

  14. Monolithic Continuous-Flow Bioreactors

    NASA Technical Reports Server (NTRS)

    Stephanopoulos, Gregory; Kornfield, Julia A.; Voecks, Gerald A.

    1993-01-01

    Monolithic ceramic matrices containing many small flow passages useful as continuous-flow bioreactors. Ceramic matrix containing passages made by extruding and firing suitable ceramic. Pores in matrix provide attachment medium for film of cells and allow free movement of solution. Material one not toxic to micro-organisms grown in reactor. In reactor, liquid nutrients flow over, and liquid reaction products flow from, cell culture immobilized in one set of channels while oxygen flows to, and gaseous reaction products flow from, culture in adjacent set of passages. Cells live on inner surfaces containing flowing nutrient and in pores of walls of passages. Ready access to nutrients and oxygen in channels. They generate continuous high yield characteristic of immobilized cells, without large expenditure of energy otherwise incurred if necessary to pump nutrient solution through dense biomass as in bioreactors of other types.

  15. Review of nonconventional bioreactor technology

    SciTech Connect

    Turick, C.E.; Mcllwain, M.E.

    1993-09-01

    Biotechnology will significantly affect many industrial sectors in the future. Industrial sectors that will be affected include pharmaceutical, chemical, fuel, agricultural, and environmental remediation. Future research is needed to improve bioprocessing efficiency and cost-effectiveness in order to compete with traditional technologies. This report describes recent advances in bioprocess technologies and bioreactor designs and relates them to problems encountered in many industrial bioprocessing operations. The primary focus is directed towards increasing gas and vapor transfer for enhanced bioprocess kinetics as well as unproved by-product separation and removal. The advantages and disadvantages of various conceptual designs such as hollow-fiber, gas-phase, hyperbaric/hypobaric, and electrochemical bioreactors are also discussed. Specific applications that are intended for improved bioprocesses include coal desulfurization, coal liquefaction, soil bioremediation, biomass conversion to marketable chemicals, biomining, and biohydrometallurgy as well as bioprocessing of gases and vapors.

  16. Mixed Waste Landfill Integrated Demonstration; Technology summary

    SciTech Connect

    1994-02-01

    The mission of the Mixed Waste Landfill Integrated Demonstration (MWLID) is to demonstrate, in contaminated sites, new technologies for clean-up of chemical and mixed waste landfills that are representative of many sites throughout the DOE Complex and the nation. When implemented, these new technologies promise to characterize and remediate the contaminated landfill sites across the country that resulted from past waste disposal practices. Characterization and remediation technologies are aimed at making clean-up less expensive, safer, and more effective than current techniques. This will be done by emphasizing in-situ technologies. Most important, MWLID`s success will be shared with other Federal, state, and local governments, and private companies that face the important task of waste site remediation. MWLID will demonstrate technologies at two existing landfills. Sandia National Laboratories` Chemical Waste Landfill received hazardous (chemical) waste from the Laboratory from 1962 to 1985, and the Mixed-Waste Landfill received hazardous and radioactive wastes (mixed wastes) over a twenty-nine year period (1959-1988) from various Sandia nuclear research programs. Both landfills are now closed. Originally, however, the sites were selected because of Albuquerque`s and climate and the thick layer of alluvial deposits that overlay groundwater approximately 480 feet below the landfills. This thick layer of ``dry`` soils, gravel, and clays promised to be a natural barrier between the landfills and groundwater.

  17. Redox zones stratification and the microbial community characteristics in a periphyton bioreactor.

    PubMed

    Liu, Junzhuo; Liu, Wei; Wang, Fengwu; Kerr, Philip; Wu, Yonghong

    2016-03-01

    Bioremediation techniques based on microorganisms have been widely applied to treat polluted surface water, but the efficiencies have been limited, especially in deep and static waters. Microbial aggregates, known as periphyton, were introduced into a tank bioreactor to improve pollutants removal and a periphyton bioreactor with an 84 cm column was built to investigate microbe-wastewater interactions. Periphyton greatly improved water quality and produced a distinct stratification in the water column into five redox zones with slight overlaps. From top to bottom these were: oxygen reduction, nitrate reduction, iron reduction, sulfate reduction and methanogenic zone. Periphyton communities had high species diversities (767-947 OTUs) with the facultative zone (middle layer) having higher species richness and functional diversity than the aerobic (top layer) and anaerobic zones (bottom layer). A good knowledge of interactions between periphyton and water column stratification could benefit from integration of periphyton to improve bioremediation of deep and static water.

  18. Aqueous- and solid-phase biogeochemistry of a calcareous aquifer system downgradient from a municipal solid waste landfill (Winterthur, Switzerland)

    SciTech Connect

    Amirbahman, A.; Schoenenberger, R.; Johnson, C.A.; Sigg, L. |

    1998-07-01

    This study addresses the biogeochemical changes that take place in a calcareous aquifer system under and down-gradient from a municipal solid waste landfill. Aqueous-phase chemical analysis of the redox-sensitive species indicates the presence of aerobic respiration, denitrification/NO{sub 3}{sup {minus}} reduction, and Fe(III), Mn(III/IV), and SO{sub 4} reduction processes under the landfill. Because available and released organic matter is limited, reduction processes downgradient from the landfill do not go far beyond aerobic respiration, denitrification, and Mn(III/IV) reduction. Assuming steady-state conditions, STEADYQL computer program has been used to model the biogeochemical processes by taking into account the kinetics of the redox reactions, calcite precipitation and dilution. Dilution has the most significant influence on the concentrations of the dissolved organic and inorganic carbon. Dissolved Mn(II) concentrations in the entire anaerobic zone are controlled by the solubility of rhodocrocite [MnCO{sub 3}(S)]. At selected locations under the landfill where SO{sub 4} reduction takes place, dissolved Fe(II) concentrations are regulated by the solubility of amorphous FeS. Chemical extraction of the aquifer solid phase indicates that the oxidation capacity of this aquifer system is largely controlled by iron(III)(hydr)-oxides.

  19. Biological technologies for the removal of sulfur containing compounds from waste streams: bioreactors and microbial characteristics.

    PubMed

    Li, Lin; Zhang, Jingying; Lin, Jian; Liu, Junxin

    2015-10-01

    Waste gases containing sulfur compounds, such as hydrogen sulfide, sulfur dioxide, thioethers, and mercaptan, produced and emitted from industrial processes, wastewater treatment, and landfill waste may cause undesirable issues in adjacent areas and contribute to atmospheric pollution. Their control has been an area of concern and research for many years. As alternative to conventional physicochemical air pollution control technologies, biological treatment processes which can transform sulfur compounds to harmless products by microbial activity, have gained in popularity due to their efficiency, cost-effectiveness and environmental acceptability. This paper provides an overview of the current biological techniques used for the treatment of air streams contaminated with sulfur compounds as well as the advances made in the past year. The discussion focuses on bioreactor configuration and design, mechanism of operation, insights into the overall biological treatment process, and the characterization of the microbial species present in bioreactors, their populations and their interactions with the environment. Some bioreactor case studies are also introduced. Finally, the perspectives on future research and development needs in this research area were also highlighted.

  20. Characterization of landfill leachates by molecular size distribution, biodegradability, and inert chemical oxygen demand.

    PubMed

    Amaral, Míriam C S; Ferreira, Cynthia F A; Lange, Liséte Celina; Aquino, Sérgio F

    2009-05-01

    This work presents results from a detailed characterization of landfill leachates of different ages from a landfill in a major Brazilian city. This characterization consists of determining the molecular size distribution and the inert chemical oxygen demand (COD) and the biodegradability of both aerobic and anaerobic processes. Results show that leachate with a high COD concentration leachate has low biodegradability. A significant fraction of the COD is not characterized as protein, carbohydrate, or lipids, which reinforces the hypothesis that the remaining fraction was present in all leachate fractions (less than 1 kDa; between 1 and 10 kDa; between 10 and 100 kDa; and greater than 100 kDa) and is refractory. These results suggest that leachates with such characteristics require treatment systems that use physical-chemical processes as a pre- or post-treatment step to biological processes.

  1. High cell density cultivation of recombinant yeasts and bacteria under non-pressurized and pressurized conditions in stirred tank bioreactors.

    PubMed

    Knoll, Arnd; Bartsch, Stefan; Husemann, Bernward; Engel, Philip; Schroer, Kirsten; Ribeiro, Betina; Stöckmann, Christoph; Seletzky, Juri; Büchs, Jochen

    2007-10-31

    This study demonstrates the applicability of pressurized stirred tank bioreactors for oxygen transfer enhancement in aerobic cultivation processes. The specific power input and the reactor pressure was employed as process variable. As model organism Escherichia coli, Arxula adeninivorans, Saccharomyces cerevisiae and Corynebacterium glutamicum were cultivated to high cell densities. By applying specific power inputs of approx. 48kWm(-3) the oxygen transfer rate of a E. coli culture in the non-pressurized stirred tank bioreactor was lifted up to values of 0.51moll(-1)h(-1). When a reactor pressure up to 10bar was applied, the oxygen transfer rate of a pressurized stirred tank bioreactor was lifted up to values of 0.89moll(-1)h(-1). The non-pressurized stirred tank bioreactor was able to support non-oxygen limited growth of cell densities of more than 40gl(-1) cell dry weight (CDW) of E. coli, whereas the pressurized stirred tank bioreactor was able to support non-oxygen limited growth of cell densities up to 225gl(-1) CDW of A. adeninivorans, 89gl(-1) CDW of S. cerevisiae, 226gl(-1) CDW of C. glutamicum and 110gl(-1) CDW of E. coli. Compared to literature data, some of these cell densities are the highest values ever achieved in high cell density cultivation of microorganisms in stirred tank bioreactors. By comparing the specific power inputs as well as the k(L)a values of both systems, it is demonstrated that only the pressure is a scaleable tool for oxygen transfer enhancement in industrial stirred tank bioreactors. Furthermore, it was shown that increased carbon dioxide partial pressures did not remarkably inhibit the growth of the investigated model organisms.

  2. Hanford Site Solid Waste Landfill permit application

    SciTech Connect

    Not Available

    1991-01-01

    Daily activities at the Hanford Site generate sanitary solid waste (nonhazardous and nonradioactive) that is transported to and permanently disposed of at the Hanford Site Solid Waste Landfill. This permit application describes the manner in which the solid Waste Landfill will be operated under Washington State Department of Ecology Minimum Functional Standards for Solid Waste Handling, Washington Administrative Code 173-304. The solid Waste Landfill is owned by the US Department of Energy -- Richland Operations Office and is used for disposal of solid waste generated at the US Department of Energy Hanford Site. The jurisdictional health department's permit application form for the Solid Waste Landfill is provided in Chapter 1.0. Chapter 2.0 provides a description of the Hanford Site and the Solid Waste Landfill and reviews applicable locational, general facility, and landfilling standards. Chapter 3.0 discusses the characteristics and quantity of the waste disposed of in the Solid Waste Landfill. Chapter 4.0 reviews the regional and site geology and hydrology and the groundwater and vadose zone quality beneath the landfill. Chapters 5.0, 6.0, and 7.0 contain the plan of operation, closure plan, and postclosure plan, respectively. The plan of operation describes the routine operation and maintenance of the Solid Waste Landfill, the environmental monitoring program, and the safety and emergency plans. Chapter 5.0 also addresses the operational cover, environmental controls, personnel requirements, inspections, recordkeeping, reporting, and site security. The postclosure plan describes requirements for final cover maintenance and environmental monitoring equipment following final closure. Chapter 8.0 discusses the integration of closure and postclosure activities between the Solid Waste Landfill and adjacent Nonradioactive Dangerous Waste Landfill. 76 refs., 48 figs, 15 tabs.

  3. Assessing the market opportunities of landfill mining.

    PubMed

    van der Zee, D J; Achterkamp, M C; de Visser, B J

    2004-01-01

    Long-term estimates make clear that the amount of solid waste to be processed at landfills in the Netherlands will sharply decline in coming years. Major reasons can be found in the availability of improved technologies for waste recycling and government regulations aiming at waste reduction. Consequently, market size for companies operating landfills shrinks. Among the companies facing the problem is the Dutch company Essent. Given the expected market conditions, it looks for alternative business opportunities. Landfill mining, i.e., the recycling of existing landfills, is considered one of them. Proceeds of landfill mining are related to, for example, recycled materials available for re-use, regained land, and possibilities for a more efficient operation of a landfill. The market for landfill mining is of a considerable size--there are about 3800 landfills located in the Netherlands. Given market size the company faces the dilemma of how to explore this market, i.e., select the most profitable landfills in a fast and efficient way. No existing methods or tools could be found to do so. Therefore, to answer to the problem posed, we propose a step-wise research method for market exploration. The basic idea behind the method is to provide an adequate, cost-saving and timely answer by relying on a series of quick scans. Relevant aspects of a mining project concern the proceeds of regained land and recyclables, the costs of the mining operation and the associated business and environmental risks. The method has been tested for its practical use in a pilot study. The pilot study addressed 147 landfills located in the Dutch Province of Noord-Brabant. The study made clear how method application resulted in the selection of a limited number of high potential landfills in a few weeks, involving minimal research costs.

  4. Sequential anaerobic-aerobic degradation of indigenous PCBs in a contaminated soil matrix

    SciTech Connect

    Klasson, K.T.; Reeves, M.E.; Evans, B.S.; Dudley, C.A.

    1994-12-31

    Many industrial locations, including the US Department of Energy`s, have identified needs for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for the treatment of PCB-contaminated soils and sludges; however, a practicable remediation technology has not yet been demonstrated. A biological treatment technology is likely to consist of an anaerobic fermentation step in which PCB dechlorination takes place producing PCBs with fewer chlorines. These products are then more susceptible to aerobic mineralization. In laboratory experiments, soil slurry bioreactors inoculated with microorganisms extracted from PCB-contaminated sediments from the Hudson River and Woods Pond have been used to obtain anaerobic dechlorination of PCBs in soil slurry reactors. The anaerobic dechlorination was followed by qualitative estimation of the effect of aerobic fermentation of the dechlorination products based on literature data. The sequential anaerobic-(simulated) aerobic treatment constituted an improvement compared anaerobic treatment alone.

  5. Characterization of landfill gas composition at the Fresh Kills municipal solid-waste landfill

    SciTech Connect

    Eklund, B.; Anderson, E.P.; Walker, B.L.; Burrows, D.B.

    1998-08-01

    The most common disposal method in the US for municipal solid waste (MSW) is burial in landfills. Until recently, air emissions from these landfills were not regulated. Under the New Source Performance Standards and Emission Guidelines for MSW landfills, MSW operators are required to determine the nonmethane organic gas generation rate of their landfill through modeling and/or measurements. This paper summarizes speciated nonmethane organic compound (NMOC) measurement data collected during an intensive, short-term field program. Over 250 separate landfill gas samples were collected from emission sources at the Fresh Kills landfill in New York City and analyzed for approximately 150 different analytes. The average total NMOC value for the landfill was 438 ppmv (as hexane) versus the regulatory default value of 4,000 ppmv (as hexane). Over 70 individual volatile organic compounds (VOCs) were detected and quantified in the landfill gas samples. The typical gas composition for this landfill was determined as well as estimates of the spatial, temporal, and measurement variability in the gas composition. The data for NMOC show that the gas composition within the landfill is equivalent to the composition of the gas exiting the landfill through passive vents and through the soil cover.

  6. LANDFILL GAS PRETREATMENT FOR FUEL CELL APPLICATIONS

    EPA Science Inventory

    The paper discusses the U.S. EPA's program, underway at International Fuel Cells Corporation, to demonstrate landfill methane control and the fuel cell energy recovery concept. In this program, two critical issues are being addressed: (1) a landfill gas cleanup method that would ...

  7. Municipal waste landfill permitting in Pennsylvania

    SciTech Connect

    Mentzer, G.F.

    1996-11-01

    The Commonwealth of Pennsylvania has 50 permitted municipal waste landfills (MWL) with calculated capacities ranging from 0.5 to 25.3 million tons. The most common size for our landfills is in the range of 3 to 5 million tons, with three landfills exceeding the 20+ million ton capacity. Future expansion projects will increase a few landfills to in excess of 35+ million tons. Exact VOC emission numbers are not available since not all landfills have or are required to report their emissions to the Pennsylvania air emissions database. However, estimates from several of our larger facilities indicates the uncontrolled VOC emissions are in the range of 250 to 350 TPY with a possible high of 580 TPY. Although the numbers are not exact, it does point out the fact that landfills are a major source of VOC emissions. With the advent of the Environmental Protection Agency`s (EPA) proposed New Source Performance Standards (Subpart WWW) and emissions guidance (Subpart Cc), the EPA declared that the MWL are a source of air pollution. Following the release of these proposed regulations, the Department of Environmental Protection, Bureau of Air Quality began in mid 1994 the task of permitting landfills. Through the use of customized forms G(A) and G(B), the Department made in 1995 its first attempt to identify and quantify emissions from its landfills. The process of quantifying and verifying emission estimates is still on going. To date, the Department is in various stages of permitting eight MWL.

  8. Field Water Balance of Landfill Final Covers

    EPA Science Inventory

    Landfill covers are critical to waste containment, yet field performance of specific cover designs has not been well documented and seldom been compared in side-by-side testing. A study was conducted to assess the ability of landfill final covers to control percolation into unde...

  9. Venice Park landfill: Working with the community

    SciTech Connect

    McAdams, C.L.

    1993-09-01

    Venice Park landfill was one of the first sites to be permitted under Michigan's proposed Public Act 641. PA 641 essentially changed the rules and regulations for landfills from the simple design of digging a hole and filling it. It also upgraded standards to those that are more sophisticated, including liners, leachate collection systems, and gas extraction systems. In 1992, methane gas from the landfill was collected into wells drilled into the trash varying in depth from 30-50 feet in depth. A vacuum pulls the gas from the trash into the wells, then through a piping system. The landfill uses about 80-100 kilowatts in-house. The remainder of the gas is sold to Consumers Power Co. which uses landfill gas to supply power to homes.

  10. Analysis of landfills with historic airphotos

    NASA Technical Reports Server (NTRS)

    Erb, T. L.; Philipson, W. R.; Teng, W. L.; Liang, T.

    1981-01-01

    An investigation is conducted regarding the value of existing aerial photographs for waste management, including landfill monitoring. The value of historic aerial photographs for documenting landfill boundaries is shown in a graph in which the expansion of an active landfill is traced over a 40-year period. Historic aerial photographs can also be analyzed to obtain general or detailed land-use and land-cover information. In addition, the photographs provide information regarding other elements of the physical environment, including geology, soils, and surface and subsurface drainage. The value of historic photos is discussed, taking into account applications for inventory, assessing contamination/health hazards, planning corrective measures, planning waste collection and facilities, developing inactive landfills, and research concerning improved land-filling operations.

  11. Carbon pools and flows during lab-scale degradation of old landfilled waste under different oxygen and water regimes

    SciTech Connect

    Brandstätter, Christian Laner, David Fellner, Johann

    2015-06-15

    Graphical abstract: Display Omitted - Highlights: • 40 year old waste from an old MSW landfill was incubated in LSR experiments. • Carbon balances for anaerobic and aerobic waste degradation were established. • The transformation of carbon pools during waste degradation was investigated. • Waste aeration resulted in the formation of a new, stable organic carbon pool. • Water addition did not have a significant effect on aerobic waste degradation. - Abstract: Landfill aeration has been proven to accelerate the degradation of organic matter in landfills in comparison to anaerobic decomposition. The present study aims to evaluate pools of organic matter decomposing under aerobic and anaerobic conditions using landfill simulation reactors (LSR) filled with 40 year old waste from a former MSW landfill. The LSR were operated for 27 months, whereby the waste in one pair was kept under anaerobic conditions and the four other LSRs were aerated. Two of the aerated LSR were run with leachate recirculation and water addition and two without. The organic carbon in the solid waste was characterized at the beginning and at the end of the experiments and major carbon flows (e.g. TOC in leachate, gaseous CO{sub 2} and CH{sub 4}) were monitored during operation. After the termination of the experiments, the waste from the anaerobic LSRs exhibited a long-term gas production potential of more than 20 NL kg{sup −1} dry waste, which corresponded to the mineralization of around 12% of the initial TOC (67 g kg{sup −1} dry waste). Compared to that, aeration led to threefold decrease in TOC (32–36% of the initial TOC were mineralized), without apparent differences in carbon discharge between the aerobic set ups with and without water addition. Based on the investigation of the carbon pools it could be demonstrated that a bit more than 10% of the initially present organic carbon was transformed into more recalcitrant forms, presumably due to the formation of humic substances

  12. A Study of Leachate Generated from Construction and Demolition Landfills,

    DTIC Science & Technology

    2007-11-02

    solid waste (MSW) landfills and hazardous waste landfills. Regulators felt that since C&D landfills did not accept large quantities of hazardous waste...Construction and demolition (C&D) waste landfills have largely been ignored because they have been viewed as innocuous in comparison to municipal

  13. Nitrate and COD removal in an upflow biofilter under an aerobic atmosphere.

    PubMed

    Ji, Bin; Wang, Hongyu; Yang, Kai

    2014-04-01

    A continuous-upflow submerged biofilter packed with ceramsite was constructed for nitrate removal under an aerobic atmosphere. Pseudomonas stutzeri X31, an aerobic denitrifier isolate, was added to the bioreactor as an inoculum. The influent NO3(-)-N concentrations were 63.0-73.8 mg L(-1). The best results were achieved when dissolved oxygen level was 4.6 mg L(-1) and C/N ratio was 4.5. The maximum removal efficiencies of carbon oxygen demand (COD) and NO3(-)-N were 94.04% and 98.48%, respectively at 30°C, when the hydraulic load was 0.75 m h(-1). The top section of the bioreactor possessed less biofilm but higher COD and NO3(-)-N removal rates than the bottom section. Polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) technique combined with electron microscopic examination indicated P. stutzeri X31 and Paracoccus versutus were the most dominant bacteria. Amoeba sp., Vorticella sp., Philodina sp., and Stephanodiscus sp. were also found in the bioreactor.

  14. Tissue grown in space in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, such as the culture section shown here, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. The two white circles within the tumor are part of a plastic lattice that helped the cells associate. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  15. Stem cell cultivation in bioreactors.

    PubMed

    Rodrigues, Carlos A V; Fernandes, Tiago G; Diogo, Maria Margarida; da Silva, Cláudia Lobato; Cabral, Joaquim M S

    2011-01-01

    Cell-based therapies have generated great interest in the scientific and medical communities, and stem cells in particular are very appealing for regenerative medicine, drug screening and other biomedical applications. These unspecialized cells have unlimited self-renewal capacity and the remarkable ability to produce mature cells with specialized functions, such as blood cells, nerve cells or cardiac muscle. However, the actual number of cells that can be obtained from available donors is very low. One possible solution for the generation of relevant numbers of cells for several applications is to scale-up the culture of these cells in vitro. This review describes recent developments in the cultivation of stem cells in bioreactors, particularly considerations regarding critical culture parameters, possible bioreactor configurations, and integration of novel technologies in the bioprocess development stage. We expect that this review will provide updated and detailed information focusing on the systematic production of stem cell products in compliance with regulatory guidelines, while using robust and cost-effective approaches.

  16. Carbon pools and flows during lab-scale degradation of old landfilled waste under different oxygen and water regimes.

    PubMed

    Brandstätter, Christian; Laner, David; Fellner, Johann

    2015-06-01

    Landfill aeration has been proven to accelerate the degradation of organic matter in landfills in comparison to anaerobic decomposition. The present study aims to evaluate pools of organic matter decomposing under aerobic and anaerobic conditions using landfill simulation reactors (LSR) filled with 40 year old waste from a former MSW landfill. The LSR were operated for 27 months, whereby the waste in one pair was kept under anaerobic conditions and the four other LSRs were aerated. Two of the aerated LSR were run with leachate recirculation and water addition and two without. The organic carbon in the solid waste was characterized at the beginning and at the end of the experiments and major carbon flows (e.g. TOC in leachate, gaseous CO2 and CH4) were monitored during operation. After the termination of the experiments, the waste from the anaerobic LSRs exhibited a long-term gas production potential of more than 20 NL kg(-1) dry waste, which corresponded to the mineralization of around 12% of the initial TOC (67 g kg(-1) dry waste). Compared to that, aeration led to threefold decrease in TOC (32-36% of the initial TOC were mineralized), without apparent differences in carbon discharge between the aerobic set ups with and without water addition. Based on the investigation of the carbon pools it could be demonstrated that a bit more than 10% of the initially present organic carbon was transformed into more recalcitrant forms, presumably due to the formation of humic substances. The source of anaerobic degradation could be identified mainly as cellulose which played a minor role during aerobic degradation in the experiment.

  17. Woodchip bioreactors for N-source reduction in a highly managed agricultural landscape

    NASA Astrophysics Data System (ADS)

    Kult, K.; Jones, C. S.

    2011-12-01

    Excess nutrification and the resulting hypoxia in the Gulf of Mexico are increasingly understood to originate in managed landscapes of the Upper Mississippi River basin. Nitrogen inputs to cropped fields are high in landscapes with soils containing high organic nitrogen content that, when mineralized, releases nitrogen in the soluble nitrate form. These in situ sources supply extensive subsurface drainage systems that rapidly transport nitrogen to streams and ultimately the Gulf. Aggressive in-field N management can reduce loading to streams, but will not reduce loads to sufficiently impact Gulf hypoxia. Edge of Field (EOF) treatment will be needed to reach water quality objectives. Denitrification bioreactors are one technology being studied for practical and economical EOF nitrate reduction. Bioreactors intercept the high-N tile-drain effluent with woodchip substrates that provide carbon and energy to support denitrification. Iowa Soybean Association (ISA) installed six bioreactors. Design of the ISA bioreactors has focused on the diameter of the field tile and the catchment area. Designs balance discharge with retention times. The bioreactors have been designed to have a 4-hour hydraulic retention time (HRT) capable of treating 20% of peak flow. Denitrification is assumed to follow zero-order kinetics given the high NO3 concentrations in the studied systems. Aerobic organisms must deplete DO sufficiently so anaerobic denitrifying organisms can compete. Insufficient HRT results in unsatisfactory NO3 reductions. Conditions favoring incomplete denitrification can lead to emission of the greenhouse gas N2O. Excessive retention times allow for complete denitrification enabling SO4-reducing bacteria to thrive. This produces undesirable results: conversion of SO4 to H2S, C-source depletion, production of toxic CH3Hg+, and methanogenesis. A flow control structure (FCS) allows for management of HRT by modifying the position of stop logs. Increased HRT reduces the amount

  18. FIELD TEST MEASUREMENTS AT FIVE MUNICIPAL SOLID WASTE LANDFILLS WITH LANDFILL GAS CONTROL TECHNOLOGY--FINAL REPORT

    EPA Science Inventory

    Research was conducted to evaluate landfill gas emissions at five municipal solid waste landfills which have modern control technology for landfill gas emissions. Comprehensive testing was conducted on the raw landfill gas and the combustion outlet exhaust. The project had two ...

  19. Bioreactor design considerations for hollow organs.

    PubMed

    Fish, Jeff; Halberstadt, Craig; McCoy, Darell W; Robbins, Neil

    2013-01-01

    There are many important considerations in the design, construction, and use of a bioreactor for growing hollow organs such as vessels, gastrointestinal tissue, esophagus, and others. The growth of new organs requires a specialized container that provides sterility and an environment conducive to cell-seeding and attachment onto a three-dimensional bioabsorbable porous scaffold, incubation, maturation, and shipping for implantation. The materials' selection, dimensions, manufacturing, testing, and use of the bioreactor are all factors that should be considered in designing a bioreactor for the development of hollow organs.

  20. Bioreactor Technology in Cardiovascular Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mertsching, H.; Hansmann, J.

    Cardiovascular tissue engineering is a fast evolving field of biomedical science and technology to manufacture viable blood vessels, heart valves, myocar-dial substitutes and vascularised complex tissues. In consideration of the specific role of the haemodynamics of human circulation, bioreactors are a fundamental of this field. The development of perfusion bioreactor technology is a consequence of successes in extracorporeal circulation techniques, to provide an in vitro environment mimicking in vivo conditions. The bioreactor system should enable an automatic hydrodynamic regime control. Furthermore, the systematic studies regarding the cellular responses to various mechanical and biochemical cues guarantee the viability, bio-monitoring, testing, storage and transportation of the growing tissue.

  1. Spatial Experiment Technologies Suitable for Unreturnable Bioreactor

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Zheng, Weibo; Tong, Guanghui

    2016-07-01

    The system composition and main function of the bioreactor piggybacked on TZ cargo transport spacecraft are introduced briefly in the paper.The spatial experiment technologies which are suitable for unreturnable bioreactor are described in detail,including multi-channel liquid transportion and management,multi-type animal cells circuit testing,dynamic targets microscopic observation in situ etc..The feasibility and effectiveness of these technologies which will be used in space experiment in bioreactor are verified in tests and experiments on the ground.

  2. GUIDANCE FOR EVALUATING LANDFILL GAS EMISSIONS ...

    EPA Pesticide Factsheets

    This document provides guidance to Superfund remedial project managers, on scene coordinators, facility owners, and potentially responsible parties for conducting an air pathway analysis for landfill gas (LFG) emissions under the Comprehensive Environmental Response, Compensation and Liability Act, Superfund Amendments and Reauthorization Act, and the Resource Conservation and Recovery Act. The document provides procedures and a set of tools for evaluating LFG emissions to ambient air, subsurface vapor migration due to landfill gas pressure gradients, and subsurface vapor intrusion into buildings. The air pathway analysis is used to evaluate the inhalation risks of offsite receptors as well as the hazards of both onsite and offsite methane explosions and landfill fires. information

  3. Exercise, Animal Aerobics, and Interpretation?

    ERIC Educational Resources Information Center

    Oliver, Valerie

    1996-01-01

    Describes an aerobic activity set to music for children that mimics animal movements. Example exercises include walking like a penguin or jumping like a cricket. Stresses basic aerobic principles and designing the program at the level of children's motor skills. Benefits include reaching people who normally don't visit nature centers, and bridging…

  4. Biodegradation of naphthenic acids in oils sands process waters in an immobilized soil/sediment bioreactor.

    PubMed

    McKenzie, Natalie; Yue, Siqing; Liu, Xudong; Ramsay, Bruce A; Ramsay, Juliana A

    2014-08-01

    Aqueous extraction of bitumen in the Alberta oil sands industry produces large volumes of oil sands process water (OSPW) containing naphthenic acids (NAs), a complex mixture of carboxylic acids that are acutely toxic to aquatic organisms. Although aerobic biodegradation reduces NA concentrations and OSPW toxicity, treatment times are long, however, immobilized cell reactors have the potential to improve NA removal rates. In this study, two immobilized soil/sediment bioreactors (ISBRs) operating in series were evaluated for treatment of NAs in OSPW. A biofilm was established from microorganisms associated with sediment particles from an OSPW contaminated wetland on a non-woven textile. At 16 months of continuous operation with OSPW as the sole source of carbon and energy, 38±7% NA removal was consistently achieved at a residence time of 160 h at a removal rate of 2.32 mg NAs L(-1)d(-1). The change in NA profile measured by gas chromatography-mass spectrometry indicated that biodegradability decreased with increasing cyclicity. These results indicate that such treatment can significantly reduce NA removal rates compared to most studies, and the treatment of native process water in a bioreactor has been demonstrated. Amplification of bacterial 16S rRNA genes and sequencing using Ion Torrent sequencing characterized the reactors' biofilm populations and found as many as 235 and 198 distinct genera in the first and second bioreactor, respectively, with significant populations of ammonium- and nitrite-oxidizers.

  5. Trichloroethylene and tetrachloroethylene elimination from the air by means of a hybrid bioreactor with immobilized biomass.

    PubMed

    Tabernacka, Agnieszka; Zborowska, Ewa

    2012-09-01

    Two-phase bioreactors consisting of bacterial consortium in suspension and sorbents with immobilized biomass were used to treat waste air containing chlorinated ethenes, trichloroethylene (TCE) and tetrachloroethylene (PCE). Synthetic municipal sewage was used as the medium for bacterial growth. The system was operated with loadings in the range 1.48-4.76 gm(-3)h(-1) for TCE and 1.49-5.96 gm(-3)h(-1) for PCE. The efficiency of contaminant elimination was 55-86% in the bioreactor with wood chips and 33-89% in the bioreactor filled with zeolite. The best results were observed 1 week after the pollutant loading was increased. However, in these conditions, the stability of the process was not achieved. In the next 7 days the effectiveness of the system decreased. Contaminant removal efficiency, enzymatic activity and the biomass content were all diminished. The system was working without being supplied with additional hydrocarbons as the growth-supporting substrates. It is assumed that ammonia produced during the transformation of wastewater components induced enzymes for the cometabolic degradation of TCE and PCE. However, the evaluation of nitrogen compound transformations in the system is difficult due to the sorption on carriers and the combined processes of nitrification and the aerobic denitrification. An applied method of air treatment is advantageous from both economic and environmental point of views.

  6. Feasibility study of moving-fiber biofilm membrane bioreactor for wastewater treatment: process control.

    PubMed

    Phattaranawik, Jirachote; Leiknes, Torove

    2011-03-01

    Non-biodegradable solid wastes of non-intact membrane fibres/flatsheets and modules disposed from membrane bioreactor (MBR) plants are in a great concern for environmental impact. Estimated cumulative amount of the module solid wastes from European countries in the next five years should be larger than 1000 tons in which a proper management strategy and reuse for the disposed solid waste are urgently required. This article was aimed to propose an alternative to make uses of the non-intact membrane fibres for the aerobic biofilm supports and to study the feasibility on process operation of novel moving-fiber biofilm MBR. A system of moving-fiber biofilm membrane bioreactor was designed and evaluated experimentally, including an upflow anaerobic sludge reactor, an aerobic moving-fiber biofilm reactor, and a submerged membrane filtration unit. Start-up method and operating conditions to control the biofilms growing on the moving fibers were investigated. Organic removal rates, optimum operating conditions for the system, and membrane fouling rates at various membrane aeration rates and permeate fluxes were monitored to evaluate the performance of the proposed BF-MBR process.

  7. Bioreactor Design for Tendon/Ligament Engineering

    PubMed Central

    Wang, Tao; Gardiner, Bruce S.; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B.; Wang, Allan; Xu, Jiake

    2013-01-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments. PMID:23072472

  8. Efficient proteolysis strategies based on microchip bioreactors.

    PubMed

    Liu, Shuang; Bao, Huimin; Zhang, Luyan; Chen, Gang

    2013-04-26

    In proteome research, proteolysis is an important procedure prior to the mass spectrometric identification of proteins. The typical time of conventional in-solution proteolysis is as long as several hours to half a day. To enhance proteolysis efficiency, a variety of microchip bioreactors have been developed for the rapid digestion and identification of proteins in the past decade. This review mainly focuses on the recent advances and the key strategies of microchip bioreactors in protein digestion. The subjects covered include microchip proteolysis systems, the immobilization of proteases in microchannels, the applications of microchip bioreactors in highly efficient proteolysis, and future prospects. It is expected that microchip bioreactors will become powerful tools in protein analysis and will find a wide range of applications in high-throughput protein identification.

  9. In vivo bioreactors for mandibular reconstruction.

    PubMed

    Tatara, A M; Wong, M E; Mikos, A G

    2014-12-01

    Large mandibular defects are difficult to reconstruct with good functional and aesthetic outcomes because of the complex geometry of craniofacial bone. While the current gold standard is free tissue flap transfer, this treatment is limited in fidelity by the shape of the harvested tissue and can result in significant donor site morbidity. To address these problems, in vivo bioreactors have been explored as an approach to generate autologous prefabricated tissue flaps. These bioreactors are implanted in an ectopic site in the body, where ossified tissue grows into the bioreactor in predefined geometries and local vessels are recruited to vascularize the developing construct. The prefabricated flap can then be harvested with vessels and transferred to a mandibular defect for optimal reconstruction. The objective of this review article is to introduce the concept of the in vivo bioreactor, describe important preclinical models in the field, summarize the human cases that have been reported through this strategy, and offer future directions for this exciting approach.

  10. Instrumentation of dredge spoil for landfill construction

    SciTech Connect

    Byle, M.J.; McCullough, M.L.; Alexander, R.; Vasuki, N.C.; Langer, J.A.

    1999-07-01

    The Delaware Solid Waste Authority's Northern Solid Waste Management Center is located outside of Wilmington Delaware at Cherry Island, a former dredge disposal site. Dredge spoils, of very low permeability, range in depths up to 30 m (100 feet) which form a natural liner and the foundation for the 140 ha (350-acre) municipal solid waste landfill. The soils beneath the landfill have been extensively instrumented to measure pore pressure, settlement and deflections, using inclinometer casings, standpipe piezometers, vibrating wire piezometers, pneumatic piezometers, settlement plates, liquid settlement gages, total pressure cells and thermistors. The nature of the existing waste and anticipated settlements (up to 6 m (19 feet)) have required some unique installation details. The instrumentation data has been integral in planning the landfilling sequence to maintain perimeter slope stability and has provided key geotechnical parameters needed for operation and construction of the landfill. The performance of the instrumentation and monitoring results are discussed.

  11. Modelling flow to leachate wells in landfills.

    PubMed

    Al-Thani, A A; Beaven, R P; White, J K

    2004-01-01

    Vertical wells are frequently used as a means of controlling leachate levels in landfills. They are often the only available dewatering option for both old landfills without any basal leachate collection layer and for newer sites where the installed drainage infrastructure has failed. When the well is pumped, a seepage face develops at the entry into the well so that the drawdown in the surrounding waste will not be as great as might be expected. The numerical groundwater flow model MODFLOW-SURFACT, which contains the functionality to model seepage surfaces, has been used to investigate the transient dewatering of a landfill. The study concludes that the position of the seepage face and information about the characteristics of the induced seepage flow field are important and should not be neglected when designing wells in landfills.

  12. Modelling flow to leachate wells in landfills

    SciTech Connect

    Al-Thani, A.A.; Beaven, R.P.; White, J.K

    2004-07-01

    Vertical wells are frequently used as a means of controlling leachate levels in landfills. They are often the only available dewatering option for both old landfills without any basal leachate collection layer and for newer sites where the installed drainage infrastructure has failed. When the well is pumped, a seepage face develops at the entry into the well so that the drawdown in the surrounding waste will not be as great as might be expected. The numerical groundwater flow model MODFLOW-SURFACT, which contains the functionality to model seepage surfaces, has been used to investigate the transient dewatering of a landfill. The study concludes that the position of the seepage face and information about the characteristics of the induced seepage flow field are important and should not be neglected when designing wells in landfills.

  13. Operating a fuel cell using landfill gas

    SciTech Connect

    Trippel, C.E.; Preston, J.L. Jr.; Trocciola, J.; Spiegel, R.

    1996-12-31

    An ONSI PC25{trademark}, 200 kW (nominal capacity) phosphoric acid fuel cell operating on landfill gas is installed at the Town of Groton Flanders Road landfill in Groton, Connecticut. This joint project by the Connecticut Light & Power Company (CL&P) which is an operating company of Northeast Utilities, the Town of Groton, International Fuel Cells (IFC), and the US EPA is intended to demonstrate the viability of installing, operating and maintaining a fuel cell operating on landfill gas at a landfill site. The goals of the project are to evaluate the fuel cell and gas pretreatment unit operation, test modifications to simplify the GPU design and demonstrate reliability of the entire system.

  14. NASA Bioreactors Advance Disease Treatments

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The International Space Station (ISS) is falling. This is no threat to the astronauts onboard, however, because falling is part of the ISS staying in orbit. The absence of gravity beyond the Earth s atmosphere is actually an illusion; at the ISS s orbital altitude of approximately 250 miles above the surface, the planet s gravitational pull is only 12-percent weaker than on the ground. Gravity is constantly pulling the ISS back to Earth, but the space station is also constantly traveling at nearly 18,000 miles per hour. This means that, even though the ISS is falling toward Earth, it is moving sideways fast enough to continually miss impacting the planet. The balance between the force of gravity and the ISS s motion creates a stable orbit, and the fact that the ISS and everything in it including the astronauts are falling at an equal rate creates the condition of weightlessness called microgravity. The constant falling of objects in orbit is not only an important principle in space, but it is also a key element of a revolutionary NASA technology here on Earth that may soon help cure medical ailments from heart disease to diabetes. In the mid-1980s, NASA researchers at Johnson Space Center were investigating the effects of long-term microgravity on human tissues. At the time, the Agency s shuttle fleet was grounded following the 1986 Space Shuttle Challenger disaster, and researchers had no access to the microgravity conditions of space. To provide a method for recreating such conditions on Earth, Johnson s David Wolf, Tinh Trinh, and Ray Schwarz developed that same year a horizontal, rotating device called a rotating wall bioreactor that allowed the growth of human cells in simulated weightlessness. Previously, cell cultures on Earth could only be grown two-dimensionally in Petri dishes, because gravity would cause the multiplying cells to sink within their growth medium. These cells do not look or function like real human cells, which grow three-dimensionally in

  15. Thin film bioreactors in space

    NASA Technical Reports Server (NTRS)

    Hughes-Fulford, M.; Scheld, H. W.

    1989-01-01

    Studies from the Skylab, SL-3 and D-1 missions have demonstrated that biological organisms grown in microgravity have changes in basic cellular functions such as DNA, mRNA and protein synthesis, cytoskeleton synthesis, glucose utilization, and cellular differentiation. Since microgravity could affect prokaryotic and eukaryotic cells at a subcellular and molecular level, space offers an opportunity to learn more about basic biological systems with one inmportant variable removed. The thin film bioreactor will facilitate the handling of fluids in microgravity, under constant temperature and will allow multiple samples of cells to be grown with variable conditions. Studies on cell cultures grown in microgravity would make it possible to identify and quantify changes in basic biological function in microgravity which are needed to develop new applications of orbital research and future biotechnology.

  16. Colon tumor cells grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These photos compare the results of colon carcinoma cells grown in a NASA Bioreactor flown on the STS-70 Space Shuttle in 1995 flight and ground control experiments. The cells grown in microgravity (left) have aggregated to form masses that are larger and more similar to tissue found in the body than the cells cultured on the ground (right). The principal investigator is Milburn Jessup of the University of Texas M. D. Anderson Cancer Center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and University of Texas M. D. Anderson Cancer Center.

  17. Heart tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Functionally connected heart cells that are capable of transmitting electrical signals are the goal for Freed and Vunjak-Novakovic. Electrophysiological recordings of engineered tissue show spontaneous contractions at a rate of 70 beats per minute (a), and paced contractions at rates of 80, 150, and 200 beats per minute respectively (b, c, and d). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and MIT.

  18. Heart tissue grown in NASA Bioreactor

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Lisa Freed and Gordana Vunjak-Novakovic, both of the Massachusetts Institute of Technology (MIT), have taken the first steps toward engineering heart muscle tissue that could one day be used to patch damaged human hearts. Cells isolated from very young animals are attached to a three-dimensional polymer scaffold, then placed in a NASA bioreactor. The cells do not divide, but after about a week start to cornect to form a functional piece of tissue. Here, a transmission electron micrograph of engineered tissue shows a number of important landmarks present in functional heart tissue: (A) well-organized myofilaments (Mfl), z-lines (Z), and abundant glycogen granules (Gly); and (D) intercalcated disc (ID) and desmosomes (DES). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: MIT

  19. Landfill mining: Developing a comprehensive assessment method.

    PubMed

    Hermann, Robert; Wolfsberger, Tanja; Pomberger, Roland; Sarc, Renato

    2016-11-01

    In Austria, the first basic technological and economic examinations of mass-waste landfills with the purpose to recover secondary raw materials have been carried out by the 'LAMIS - Landfill Mining Österreich' pilot project. A main focus of its research, and the subject of this article, is the first conceptual design of a comprehensive assessment method for landfill mining plans, including not only monetary factors (like costs and proceeds) but also non-monetary ones, such as the concerns of adjoining owners or the environmental impact. Detailed reviews of references, the identification of influences and system boundaries to be included in planning landfill mining, several expert workshops and talks with landfill operators have been performed followed by a division of the whole assessment method into preliminary and main assessment. Preliminary assessment is carried out with a questionnaire to rate juridical feasibility, the risk and the expenditure of a landfill mining project. The results of this questionnaire are compiled in a portfolio chart that is used to recommend, or not, further assessment. If a detailed main assessment is recommended, defined economic criteria are rated by net present value calculations, while ecological and socio-economic criteria are examined in a utility analysis and then transferred into a utility-net present value chart. If this chart does not support making a definite statement on the feasibility of the project, the results must be further examined in a cost-effectiveness analysis. Here, the benefit of the particular landfill mining project per capital unit (utility-net present value ratio) is determined to make a final distinct statement on the general benefit of a landfill mining project.

  20. Landfill aeration worldwide: Concepts, indications and findings

    SciTech Connect

    Ritzkowski, M.; Stegmann, R.

    2012-07-15

    Highlights: Black-Right-Pointing-Pointer Different landfill aeration concepts and accordant application areas are described. Black-Right-Pointing-Pointer Examples of full scale projects are provided for Europe, North-America and Asia. Black-Right-Pointing-Pointer Major project findings are summarised, including prospects and limitations. Black-Right-Pointing-Pointer Inconsistencies between laboratory and full scale results have been elaborated. Black-Right-Pointing-Pointer An explanatory approach in connection with the inconsistencies is provided. - Abstract: The creation of sustainable landfills is a fundamental goal in waste management worldwide. In this connection landfill aeration contributes towards an accelerated, controlled and sustainable conversion of conventional anaerobic landfills into a biological stabilized state associated with a minimised emission potential. The technology has been successfully applied to landfills in Europe, North America and Asia, following different strategies depending on the geographical region, the specific legislation and the available financial resources. Furthermore, methodologies for the incorporation of landfill aeration into the carbon trade mechanisms have been developed in recent years. This manuscript gives an overview on existing concepts for landfill aeration; their application ranges and specifications. For all of the described concepts examples from different countries worldwide are provided, including details regarding their potentials and limitations. Some of the most important findings from these aeration projects are summarised and future research needs have been identified. It becomes apparent that there is a great demand for a systematisation of the available results and implications in order to further develop and optimise this very promising technology. The IWWG (International Waste Working Group) Task Group 'Landfill Aeration' contributes towards the achievement of this goal.

  1. Hollow fiber vs. flat sheet MBR for the treatment of high strength stabilized landfill leachate.

    PubMed

    Hashisho, J; El-Fadel, M; Al-Hindi, M; Salam, D; Alameddine, I

    2016-09-01

    The Membrane Bioreactor (MBR) technology is increasingly becoming a prominent process in the treatment of high-strength wastewater such as leachate resulting from the decomposition of waste in landfills. This study presents a performance comparative assessment of flat sheet and hollow fiber membranes in bioreactors for the treatment of relatively stable landfill leachate with the objective of defining guidelines for pilot/full scale plants. For this purpose, a laboratory scale MBR system was constructed and operated to treat a leachate with Chemical Oxygen Demand (COD) (3900-7800mg/L), Biochemical Oxygen Demand (BOD5) (∼440-1537mg/L), Total Phosphorus (TP) (∼10-59mg/L), Phosphate (PO4(3)(-)) (5-58mg/L), Total Nitrogen (TN) (1500-5200mg/L), and ammonium (NH4(+)) (1770-4410mg/L). Both membranes achieved comparable BOD (92.2% vs. 93.2%) and TP (79.4% vs. 78.5%) removals. Higher PO4(3)(-) removal efficiency or percentage (87.3% vs. 81.3%) and slightly higher, but not statistically significant, COD removal efficiency were obtained with the hollow fiber membrane (71.4% vs. 68.5%). On the other hand, the flat sheet membrane achieved significantly higher TN and NH4(+) removal efficiencies (61.2% vs. 49.4% and 63.4% vs. 47.8%, respectively), which may be attributed to the less frequent addition of NaOCl compared to the hollow fiber system.

  2. Occurrence and treatment efficiency of pharmaceuticals in landfill leachates.

    PubMed

    Lu, Mu-Chen; Chen, Yao Yin; Chiou, Mei-Rung; Chen, Men Yu; Fan, Huan-Jung

    2016-09-01

    Landfill leachates might contain pharmaceuticals due to the expired or unwanted drugs were disposed of at landfills. These pharmaceuticals might pose a threat to soil and groundwater. Therefore, this study investigated the distributions of pharmaceutical residues and toxicities among four typical municipal landfill leachates. Twenty six pharmaceuticals were investigated in this study and fifteen of them were found in all samples from four leachates. In addition, ampicillin and methylenedioxymethamphetamine (MDMA) were detected in urban landfills (A1 and A2) but were not in rural and suburb landfills (B and C). On the other hand, some compounds were much more abundant in suburb/rural landfill leachates than those in urban landfills including diclofenac, gemfibrozil and amphetamine. Landfill leachate treatment plants could not remove most of the pharmaceuticals effectively. Landfill leachates without proper treatments would have significant adverse health impacts on human and aquatic life.

  3. Effect of leachate injection modes on municipal solid waste degradation in anaerobic bioreactor.

    PubMed

    Benbelkacem, H; Bayard, R; Abdelhay, A; Zhang, Y; Gourdon, R

    2010-07-01

    Three pilots simulated landfill bioreactors were used to investigate the effect of leachate injection modes on anaerobic digestion and biogas production from municipal solid waste. The technical modes used to increase waste moisture consisted of an initial saturation of the waste by flushing with leachate followed by a quick drainage, or weekly leachate injections with two different rates. The results confirmed that increasing moisture content is a key parameter to boost the biological reactions. Weekly leachate injection with high flow rate led to better results than the initial saturation of the waste in terms of biogas production kinetics. Water percolation was found to be an important factor to accelerate the degradation of solid waste. However, a modelling of the collected data by Gompertz model clearly showed that the intrinsic biogas potential determined on the initial solid waste was not reached with any of the progressive leachate injection modes.

  4. The performance of Electro-Fenton oxidation in the removal of coliform bacteria from landfill leachate.

    PubMed

    Aziz, Hamidi Abdul; Othman, Osama Mohammed; Abu Amr, Salem S

    2013-02-01

    Leachate pollution is one of the main problems in landfilling. Researchers have yet to find an effective solution to this problem. The technology that can be used may differ based on the type of leachate produced. Coliform bacteria were recently reported as one of the most problematic pollutants in semi-aerobic (stabilized) leachate. In the present study, the performance of the Electro-Fenton process in removing coliform from leachate was investigated. The study focused on two types of leachate: Palau Borung landfill leachate with low Coliform content (200 MPN/100 m/L) and Ampang Jajar landfill leachate with high coliform content (>24 × 10(4)MPN/100 m/L). Optimal conditions for the Electro-Fenton treatment process were applied on both types of leachate. Then, the coliform was examined before and after treatment using the Most Probable Number (MPN) technique. Accordingly, 100% removal of coliform was obtained at low initial coliform content, whereas 99.9% removal was obtained at high initial coliform content. The study revealed that Electro-Fenton is an efficient process in removing high concentrations of pathogenic microorganisms from stabilized leachate.

  5. Development of numerical model for predicting heat generation and temperatures in MSW landfills.

    PubMed

    Hanson, James L; Yeşiller, Nazli; Onnen, Michael T; Liu, Wei-Lien; Oettle, Nicolas K; Marinos, Janelle A

    2013-10-01

    A numerical modeling approach has been developed for predicting temperatures in municipal solid waste landfills. Model formulation and details of boundary conditions are described. Model performance was evaluated using field data from a landfill in Michigan, USA. The numerical approach was based on finite element analysis incorporating transient conductive heat transfer. Heat generation functions representing decomposition of wastes were empirically developed and incorporated to the formulation. Thermal properties of materials were determined using experimental testing, field observations, and data reported in literature. The boundary conditions consisted of seasonal temperature cycles at the ground surface and constant temperatures at the far-field boundary. Heat generation functions were developed sequentially using varying degrees of conceptual complexity in modeling. First a step-function was developed to represent initial (aerobic) and residual (anaerobic) conditions. Second, an exponential growth-decay function was established. Third, the function was scaled for temperature dependency. Finally, an energy-expended function was developed to simulate heat generation with waste age as a function of temperature. Results are presented and compared to field data for the temperature-dependent growth-decay functions. The formulations developed can be used for prediction of temperatures within various components of landfill systems (liner, waste mass, cover, and surrounding subgrade), determination of frost depths, and determination of heat gain due to decomposition of wastes.

  6. Passive drainage and biofiltration of landfill gas: Australian field trial

    SciTech Connect

    Dever, S.A. . E-mail: stuart_dever@ghd.com.au; Swarbrick, G.E. . E-mail: g.swarbrick@unsw.edu.au; Stuetz, R.M. . E-mail: r.stuetz@unsw.edu.au

    2007-07-01

    In Australia a significant number of landfill waste disposal sites do not incorporate measures for the collection and treatment of landfill gas. This includes many old/former landfill sites, rural landfill sites, non-putrescible solid waste and inert waste landfill sites, where landfill gas generation is low and it is not commercially viable to extract and beneficially utilize the landfill gas. Previous research has demonstrated that biofiltration has the potential to degrade methane in landfill gas, however, the microbial processes can be affected by many local conditions and factors including moisture content, temperature, nutrient supply, including the availability of oxygen and methane, and the movement of gas (oxygen and methane) to/from the micro-organisms. A field scale trial is being undertaken at a landfill site in Sydney, Australia, to investigate passive drainage and biofiltration of landfill gas as a means of managing landfill gas emissions at low to moderate gas generation landfill sites. The design and construction of the trial is described and the experimental results will provide in-depth knowledge on the application of passive gas drainage and landfill gas biofiltration under Sydney (Australian) conditions, including the performance of recycled materials for the management of landfill gas emissions.

  7. Estimation of municipal solid waste landfill settlement

    SciTech Connect

    Ling, H.I.; Leshchinsky, D.; Mohri, Yoshiyuki; Kawabata, Toshinori

    1998-01-01

    The municipal solid waste landfill suffers from large postclosure settlement that occurs over an extended period of time. A large differential settlement may impair foundations, utilities, and other associated facilities constructed on top of a landfill. It may also lead to breakage of the geomembrane and damage of the cover system in a modern municipal solid waste landfill. The waste material exhibits heterogeneous engineering properties that vary over locations and time within a landfill. These factors, combined with the fact that a landfill is not fully saturated, render a traditional soil mechanics approach less attractive for settlement prediction. An empirical approach of expressing settlement rate using logarithmic and power relationships is commonly used in conjunction with an observational procedure. In this paper, validity of these functions is reexamined based on published settlement results from three landfill sites. A hyperbolic function is proposed as an improved tool to simulate the settlement-time relationships, as well as to detect final settlement. The relationships between the parameters of these empirical functions and water content are examined.

  8. A statistical model for landfill surface emissions.

    PubMed

    Héroux, Martin; Guy, Christophe; Millette, Denis

    2010-02-01

    Landfill operators require a rapid, simple, low-cost, and accurate method for estimation of landfill methane surface emissions over time. Several methods have been developed to obtain instantaneous field measurements of landfill methane surface emissions. This paper provides a methodology for interpolating instantaneous measurements over time, taking variations in meteorological conditions into account. The goal of this study was to determine the effects of three factors on landfill methane surface emissions: air temperature, pressure gradient between waste and atmosphere, and soil moisture content of the cover material. On the basis of a statistical three-factor and two-level full factorial design, field measurements of methane emissions were conducted at the City of Montreal landfill site during the summer of 2004. Three areas were measured: test area 1 (4800 m2), test area 2 (1400 m2), and test area 3 (1000 m2). Analyses of variance were performed on the data. They showed a significant statistical effect of the three factors and the interaction between temperature and soil moisture content on methane emissions. Analysis also led to the development of a multifactor correlation, which can be explained by the underlying processes of diffusive and advective flow and biological oxidation. This correlation was used to estimate total emissions of the three test areas for July and August 2004. The approach was validated using a second dataset for another area adjacent to the landfill.

  9. Sanitary Landfill 1991 annual groundwater monitoring report

    SciTech Connect

    Thompson, C.Y.; Norrell, G.T.; Bennett, C.B.

    1992-02-01

    The Savannah River Site (SRS) Sanitary Landfill is an approximately seventy acre site located just south of SRS Road C between the Savannah River Site`s B-Area and Upper Three Runs Creek. Results from the first through third quarter 1991 groundwater monitoring date continue to show evidence of elevated levels of several hazardous constituents beneath the Sanitary Landfill: tritium, vinyl chloride, total radium, cadmium, 1,1,1-trichloroethane, 1,2 dichloroethane, 1,4 dichlorobenzene, trichloroethylene (TCE), tetrachloroethylene, and 1,1 dichloroethylene in excess of the primary drinking water standards were observed in at least one well monitoring the Sanitary Landfill during the third quarter of 1991. All of these constituents, except radium, were observed in the lower half of the original thirty-two acre site or the southern expansion site. Trichloroethylene and vinyl chloride are the primary organic contaminants in groundwater beneath the Sanitary Landfill. Vinyl chloride has become the primary contaminant during 1991. Elevated levels of benzene were consistently detected in LFW 7 in the past, but were not present in any LFW wells during the third quarter of 1991. A minor tritium plume is present in the central part of original thirty-two acre landfill. Elevated levels of tritium above the PDWS were consistently present in LFW 10A through 1991. This well has exhibited elevated tritium activities since the second quarter of 1989. Contaminant concentrations in the Sanitary Landfill are presented and discussed in this report.

  10. Sanitary Landfill 1991 annual groundwater monitoring report

    SciTech Connect

    Thompson, C.Y.; Norrell, G.T.; Bennett, C.B.

    1992-02-01

    The Savannah River Site (SRS) Sanitary Landfill is an approximately seventy acre site located just south of SRS Road C between the Savannah River Site's B-Area and Upper Three Runs Creek. Results from the first through third quarter 1991 groundwater monitoring date continue to show evidence of elevated levels of several hazardous constituents beneath the Sanitary Landfill: tritium, vinyl chloride, total radium, cadmium, 1,1,1-trichloroethane, 1,2 dichloroethane, 1,4 dichlorobenzene, trichloroethylene (TCE), tetrachloroethylene, and 1,1 dichloroethylene in excess of the primary drinking water standards were observed in at least one well monitoring the Sanitary Landfill during the third quarter of 1991. All of these constituents, except radium, were observed in the lower half of the original thirty-two acre site or the southern expansion site. Trichloroethylene and vinyl chloride are the primary organic contaminants in groundwater beneath the Sanitary Landfill. Vinyl chloride has become the primary contaminant during 1991. Elevated levels of benzene were consistently detected in LFW 7 in the past, but were not present in any LFW wells during the third quarter of 1991. A minor tritium plume is present in the central part of original thirty-two acre landfill. Elevated levels of tritium above the PDWS were consistently present in LFW 10A through 1991. This well has exhibited elevated tritium activities since the second quarter of 1989. Contaminant concentrations in the Sanitary Landfill are presented and discussed in this report.

  11. Transpiration as landfill leachate phytotoxicity indicator.

    PubMed

    Białowiec, Andrzej

    2015-05-01

    An important aspect of constructed wetlands design for landfill leachate treatment is the assessment of landfill leachate phytotoxicity. Intravital methods of plants response observation are required both for lab scale toxicity testing and field examination of plants state. The study examined the toxic influence of two types of landfill leachate from landfill in Zakurzewo (L1) and landfill in Wola Pawłowska (L2) on five plant species: reed Phragmites australis (Cav.) Trin. ex Steud, manna grass Glyceria maxima (Hartm.) Holmb., bulrush Schoenoplectus lacustris (L.) Palla, sweet flag Acorus calamus L., and miscanthus Miscanthus floridulus (Labill) Warb. Transpiration measurement was used as indicator of plants response. The lowest effective concentration causing the toxic effect (LOEC) for each leachate type and plant species was estimated. Plants with the highest resistance to toxic factors found in landfill leachate were: sweet flag, bulrush, and reed. The LOEC values for these plants were, respectively, 17%, 16%, 9% in case of leachate L1 and 21%, 18%, 14% in case of L2. Leachate L1 was more toxic than L2 due to a higher pH value under similar ammonia nitrogen content, i.e. pH 8.74 vs. pH 8.00.

  12. Estimation of flow and transport parameters for woodchip based bioreactors: I. laboratory-scale bioreactor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In subsurface bioreactors used for tile drainage systems, carbon sources are used to facilitate denitrification. The objective of this study was to estimate hydraulic conductivity, effective porosity, dispersivity, and first-order decay coefficients for a laboratory-scale bioreactor with woodchips a...

  13. Elucidation of nitrate reduction pathways in anaerobic bioreactors using a stable isotope approach.

    PubMed

    Mazéas, Laurent; Vigneron, Vassilia; Le-Ménach, Karyn; Budzinski, Hélène; Audic, Jean-Marc; Bernet, Nicolas; Bouchez, Théodore

    2008-06-01

    Leachate recirculation allows an increase of moisture content and the enhancement of the anaerobic digestion of wastes in landfill. Since there is no ammonia elimination process in landfill when leachate is recirculated, NH(4) (+) may accumulate. One strategy for NH(4) (+) removal is to treat aerobically the leachate outside the landfill to convert NH(4) (+) into NO(3) (-). When nitrified leachate is recirculated, denitrification should occur in the waste. We have previously shown that wastes have a large capacity to convert nitrate into N(2). Nevertheless, in some cases we observed nitrate reduction without gaseous nitrogen production. Using a stepwise multiple regression models, H(2)S concentration was the unique parameter found to have a negative effect on N(2) production. We then suspected that dissimilatory nitrate reduction to ammonium (DNRA) occurred in the presence of H(2)S. In order to verify this hypothesis, (15)N nitrate injections were performed into microcosms containing different H(2)S concentrations. The ammonium (15)N enrichment was measured using an elemental analyser coupled to an isotope ratio mass spectrometer. In the two microcosms containing the highest H(2)S concentrations, the ammonium was (15)N enriched and at the end of the experiment all the added nitrate was converted into ammonium. For the two microcosms containing the lowest H(2)S concentrations, no (15)N enrichment of ammonium was observed. This isotopic approach has allowed us to demonstrate that, in the presence of significant concentrations of H(2)S, denitrification is replaced by DNRA.

  14. Landfill reclamation feasibility study for the Springs-Fireplace Road Landfill, town of East Hampton, New York. Final report

    SciTech Connect

    1998-01-01

    A landfill reclamation feasibility study was performed at the Springs-Fireplace Road Landfill in East Hampton, Long Island, New York. The purpose of the study was to determine whether landfill reclamation at the Springs-Fireplaces Road Landfill is a technically and economically feasible alternative to conventional landfill closure via capping. The technical feasibility of landfill reclamation at the site was determined from a field investigation in which the waste from different periods in the landfill`s history was characterized, the percent of reusable and recyclable materials determined, environmental hazards assessed, and throughput rates determined. Potential markets and/or uses for reclaimed materials were identified and estimates for the re-disposal of the residual waste were obtained from waste-to-energy facilities and offsite landfills.

  15. Photovoltaics on Landfills in Puerto Rico

    SciTech Connect

    Salasovich, J.; Mosey, G.

    2011-01-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Commonwealth of Puerto Rico for a feasibility study of m0treAlables on several brownfield sites. The EPA defines a brownfield as 'a property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.' All of the brownfields in this study are landfill sites. Citizens of Puerto Rico, city planners, and site managers are interested in redevelopment uses for landfills in Puerto Rico, which are particularly well suited for solar photovoltaic (PV) installation. The purpose of this report is to assess the landfills with the highest potential for possible solar PV installation and estimate cost, performance, and site impacts of three different PV options: crystalline silicon (fixed-tilt), crystalline silicon (single-axis tracking), and thin film (fixed-tilt). Each option represents a standalone system that can be sized to use an entire available site area. In addition, the report outlines financing options that could assist in the implementation of a system. The feasibility of PV systems installed on landfills is highly impacted by the available area for an array, solar resource, operating status, landfill cap status, distance to transmission lines, and distance to major roads. All of the landfills in Puerto Rico were screened according to these criteria in order to determine the sites with the greatest potential. Eight landfills were chosen for site visits based on the screening criteria and location. Because of time constraints and the fact that Puerto Rico is a relatively large island, the eight landfills for this visit were all located in the eastern half of the island. The findings from this report can be applied to landfills in the western half of the island. The economics of a potential PV system on landfills in Puerto Rico depend greatly on the

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

    PubMed

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

    2016-09-01

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

  17. Phytoremediation of Landfill Leachate with Colocasia esculenta, Gynerum sagittatum and Heliconia psittacorum in Constructed Wetlands.

    PubMed

    Madera-Parra, C A; Peña-Salamanca, E J; Peña, M R; Rousseau, D P L; Lens, P N L

    2015-01-01

    This study assessed the accumulation of Cd (II), Hg (II), Cr (VI) and Pb (II) in Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) planted in constructed wetlands treating synthetic landfill leachate. Sixteen bioreactors were operated in two experimental blocks. Metal concentrations in the influent and effluent; root, stem, branch and leaves of plants were analysed, as well as COD, N-NH4+, TKN, T, pH, ORP, DO, and EC. Average removal efficiencies of COD, TKN and NH4+-N were 66, 67 and 72%, respectively and heavy metal removal ranged from 92 to 98% in all units. Cr (VI) was not detected in any effluent sample. The bioconcentration factors (BCF) were 10(0) -10(2). The BCF of Cr (VI) was the lowest: 0.59 and 2.5 (L kg(-1)) for Gs and He respectively; whilst Cd (II) had the highest (130-135 L kg(-1)) for Gs. Roots showed a higher metal content than shoots. Translocation factors (TF) were lower, He was the plant exhibiting TFs>1 for Pb (II), Cr (T) and Hg (II) and 0.4-0.9 for Cd (II) and Cr (VI). The evaluated plants demonstrate their suitability for phytoremediation of landfill leachate and all of them can be categorized as metals accumulators.

  18. The pathway of in-situ ammonium removal from aerated municipal solid waste bioreactor: nitrification/denitrification or air stripping?

    PubMed

    Hao, Yong-Jun; Ji, Min; Chen, Ying-Xu; Wu, Wei-Xiang; Hao, Yong-Jun; Zhang, Shu-Guang; Liu, Han-Qiao

    2010-12-01

    In-situ ammonium removal from municipal solid waste (MSW) landfill is an attractive method due to its economic advantages. In this study, two simulated MSW bioreactors with different degrees of initial bio-stabilization were utilized to investigate the effects of intermittent aeration mode and the addition of activated sludge on the removal of ammonium. The results showed that up to 90% of ammonium could be removed and the amount of NO(x)-N produced was less than 1% of NH4 (+)-N removed in both reactors. The pH values increased rapidly and finally arrived at a high level of 8.5-8.8. The efficiency of ammonium removal was improved by increasing the continuous aeration time, but it was not affected by the addition of activated sludge. A portion of liquid escaped from the reactors in the form of vapour, and as high as 195-258 mg L(-1) of NH(4) ( +)-N was detected in the vapour collector. According to calculation, nitrification was inhibited by the high level of free ammonia in the bioreactors. As a result, air stripping was enhanced and became the primary pathway of ammonium removal. Therefore, controlling free ammonia concentration was essential in ammonium removal from the aerated MSW bioreactor.

  19. Municipal solid waste landfills harbor distinct microbiomes

    USGS Publications Warehouse

    Stamps, Blake W.; Lyles, Christopher N.; Suflita, Joseph M.; Masoner, Jason R.; Cozzarelli, Isabelle M.; Kolpin, Dana W.; Stevenson, Bradley S.

    2016-01-01

    Landfills are the final repository for most of the discarded material from human society and its “built environments.” Microorganisms subsequently degrade this discarded material in the landfill, releasing gases (largely CH4 and CO2) and a complex mixture of soluble chemical compounds in leachate. Characterization of “landfill microbiomes” and their comparison across several landfills should allow the identification of environmental or operational properties that influence the composition of these microbiomes and potentially their biodegradation capabilities. To this end, the composition of landfill microbiomes was characterized as part of an ongoing USGS national survey studying the chemical composition of leachates from 19 non-hazardous landfills across 16 states in the continental U.S. The landfills varied in parameters such as size, waste composition, management strategy, geography, and climate zone. The diversity and composition of bacterial and archaeal populations in leachate samples were characterized by 16S rRNA gene sequence analysis, and compared against a variety of physical and chemical parameters in an attempt to identify their impact on selection. Members of the Epsilonproteobacteria, Gammaproteobacteria, Clostridia, and candidate division OP3 were the most abundant. The distribution of the observed phylogenetic diversity could best be explained by a combination of variables and was correlated most strongly with the concentrations of chloride and barium, rate of evapotranspiration, age of waste, and the number of detected household chemicals. This study illustrates how leachate microbiomes are distinct from those of other natural or built environments, and sheds light on the major selective forces responsible for this microbial diversity.

  20. Municipal Solid Waste Landfills Harbor Distinct Microbiomes

    PubMed Central

    Stamps, Blake W.; Lyles, Christopher N.; Suflita, Joseph M.; Masoner, Jason R.; Cozzarelli, Isabelle M.; Kolpin, Dana W.; Stevenson, Bradley S.

    2016-01-01

    Landfills are the final repository for most of the discarded material from human society and its “built environments.” Microorganisms subsequently degrade this discarded material in the landfill, releasing gases (largely CH4 and CO2) and a complex mixture of soluble chemical compounds in leachate. Characterization of “landfill microbiomes” and their comparison across several landfills should allow the identification of environmental or operational properties that influence the composition of these microbiomes and potentially their biodegradation capabilities. To this end, the composition of landfill microbiomes was characterized as part of an ongoing USGS national survey studying the chemical composition of leachates from 19 non-hazardous landfills across 16 states in the continental U.S. The landfills varied in parameters such as size, waste composition, management strategy, geography, and climate zone. The diversity and composition of bacterial and archaeal populations in leachate samples were characterized by 16S rRNA gene sequence analysis, and compared against a variety of physical and chemical parameters in an attempt to identify their impact on selection. Members of the Epsilonproteobacteria, Gammaproteobacteria, Clostridia, and candidate division OP3 were the most abundant. The distribution of the observed phylogenetic diversity could best be explained by a combination of variables and was correlated most strongly with the concentrations of chloride and barium, rate of evapotranspiration, age of waste, and the number of detected household chemicals. This study illustrates how leachate microbiomes are distinct from those of other natural or built environments, and sheds light on the major selective forces responsible for this microbial diversity. PMID:27148222

  1. Town of Edinburg landfill reclamation demonstration project. Final report

    SciTech Connect

    Not Available

    1992-05-15

    Landfill reclamation is the process of excavating a solid waste landfill to recover materials, reduce environmental impacts, restore the land resource, and, in some cases, extend landfill life. Using conventional surface mining techniques and specialized separation equipment, a landfill may be separated into recyclable material, combustible material, a soil/compost fraction and residual waste. A landfill reclamation demonstration project was hosted at the Town of Edinburg municipal landfill in northwest Saratoga County. The report examines various separation techniques employed at the site and appropriate uses for reclaimed materials. Specifications regarding engineered work plans, health and safety monitoring, and contingency preparedness are discussed. Major potential applications and benefits of using landfill reclamation technology at existing landfills are identified and discussed. The research and development aspect of the report also examines optimal screening technologies, site selection protocol and the results of a test burn of reclaimed waste at a waste-to-energy facility. Landfill reclamation costs are developed, and economic comparisons are made between reclamation costs and conventional landfill closure costs, with key criteria identified. The results indicate that, although dependent on site-specific conditions and economic factors, landfill reclamation can be a technically and economically feasible alternative or companion to conventional landfill closure under a range of favorable conditions. Feasibility can be determined only after an investigation of the variety of landfill conditions and reclamation options.

  2. LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL

    SciTech Connect

    Don Augenstein

    1999-01-11

    ''Conventional'' waste landfills emit methane, a potent greenhouse gas, in quantities such that landfill methane is a major factor in global climate change. Controlled landfilling is a novel approach to manage landfills for rapid completion of total gas generation, maximizing gas capture and minimizing emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated and brought to much earlier completion by improving conditions for biological processes (principally moisture levels) in the landfill. Gas recovery efficiency approaches 100% through use of surface membrane cover over porous gas recovery layers operated at slight vacuum. A field demonstration project's results at the Yolo County Central Landfill near Davis, California are, to date, highly encouraging. Two major controlled landfilling benefits would be the reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role in reduction of US greenhouse gas emissions.

  3. Physical and Biological Release of Poly- and Perfluoroalkyl Substances (PFASs) from Municipal Solid Waste in Anaerobic Model Landfill Reactors.

    PubMed

    Allred, B McKay; Lang, Johnsie R; Barlaz, Morton A; Field, Jennifer A

    2015-07-07

    A wide variety of consumer products that are treated with poly- and perfluoroalkyl substances (PFASs) and related formulations are disposed of in landfills. Landfill leachate has significant concentrations of PFASs and acts as secondary point sources to surface water. This study models how PFASs enter leachate using four laboratory-scale anaerobic bioreactors filled with municipal solid waste (MSW) and operated over 273 days. Duplicate reactors were monitored under live and abiotic conditions to evaluate influences attributable to biological activity. The biologically active reactors simulated the methanogenic conditions that develop in all landfills, producing ∼140 mL CH4/dry g refuse. The average total PFAS leaching measured in live reactors (16.7 nmol/kg dry refuse) was greater than the average for abiotic reactors (2.83 nmol/kg dry refuse), indicating biological processes were primarily responsible for leaching. The low-level leaching in the abiotic reactors was primarily due to PFCAs ≤C8 (2.48 nmol/kg dry refuse). Concentrations of known biodegradation intermediates, including methylperfluorobutane sulfonamide acetic acid and the n:2 and n:3 fluorotelomer carboxylates, increased steadily after the onset of methanogenesis, with the 5:3 fluorotelomer carboxylate becoming the single most concentrated PFAS observed in live reactors (9.53 nmol/kg dry refuse).

  4. Pathways of sulfide oxidation by haloalkaliphilic bacteria in limited-oxygen gas lift bioreactors.

    PubMed

    Klok, Johannes B M; van den Bosch, Pim L F; Buisman, Cees J N; Stams, Alfons J M; Keesman, Karel J; Janssen, Albert J H

    2012-07-17

    Physicochemical processes, such as the Lo-cat and Amine-Claus process, are commonly used to remove hydrogen sulfide from hydrocarbon gas streams such as landfill gas, natural gas, and synthesis gas. Biodesulfurization offers environmental advantages, but still requires optimization and more insight in the reaction pathways and kinetics. We carried out experiments with gas lift bioreactors inoculated with haloalkaliphilic sulfide-oxidizing bacteria. At oxygen-limiting levels, that is, below an O(2)/H(2)S mole ratio of 1, sulfide was oxidized to elemental sulfur and sulfate. We propose that the bacteria reduce NAD(+) without direct transfer of electrons to oxygen and that this is most likely the main route for oxidizing sulfide to elemental sulfur which is subsequently oxidized to sulfate in oxygen-limited bioreactors. We call this pathway the limited oxygen route (LOR). Biomass growth under these conditions is significantly lower than at higher oxygen levels. These findings emphasize the importance of accurate process control. This work also identifies a need for studies exploring similar pathways in other sulfide oxidizers such as Thiobacillus bacteria.

  5. Estimation of the environmental risk posed by landfills using chemical, microbiological and ecotoxicological testing of leachates.

    PubMed

    Matejczyk, Marek; Płaza, Grażyna A; Nałęcz-Jawecki, Grzegorz; Ulfig, Krzysztof; Markowska-Szczupak, Agata

    2011-02-01

    The leachates from 22 municipal solid waste (MSW) landfill sites in Southern Poland were characterized by evaluation of chemical, microbiological and ecotoxicological parameters. Chemical analyses were mainly focused on the identification of the priority hazardous substances according to Directive on Priority Substances, 2008/105/EC (a daughter directive of the WFD) in leachates. As showed, only five substances (Cd, Hg, hexachlorobutadiene, pentachlorobenzene and PAHs) were detected in the leachates. The compounds tested were absent or present at very low concentrations. Among them, only PAHs were found in all samples in the range from 0.057 to 77.2 μg L⁻¹. The leachates were contaminated with bacteria, including aerobic, psychrophilic and mesophilic bacteria, coliform and fecal coliforms, and spore-forming-bacteria, including Clostridium perfringens, and with filamentous fungi. From the analysis of specific microorganism groups (indicators of environmental pollution by pathogenic or opportunistic pathogenic organisms) it can be concluded that the landfill leachates showed sanitary and epidemiological hazard. In the ecotoxicological study, a battery of tests comprised of 5 bioassays, i.e. Microtox(®), Spirotox, Rotoxkit F™, Thamnotoxkit F™ and Daphtoxkit F™ magna was applied. The leachate samples were classified as toxic in 13.6%, highly toxic in 54.6% and very highly toxic in 31.8%. The Spirotox test was the most sensitive bioassay used. The percentage of class weight score was very high - above 60%; these samples could definitely be considered seriously hazardous and acutely toxic to the fauna and microflora. No correlations were found between the toxicity values and chemical parameters. The toxicity of leachate samples cannot be explained by low levels of the priority pollutants. It seems that other kinds of xenobiotics present in the samples at subacute levels gave the high aggregate toxic effect. The chemical, ecotoxicological and microbiological

  6. Treatment of landfill leachate in municipal wastewater treatment plants and impacts on effluent ammonium concentrations.

    PubMed

    Brennan, R B; Clifford, E; Devroedt, C; Morrison, L; Healy, M G

    2017-03-01

    Landfill leachate is the result of water percolating through waste deposits that have undergone aerobic and anaerobic microbial decomposition. In recent years, increasingly stringent wastewater discharge requirements have raised questions regarding the efficacy of co-treatment of leachate in municipal wastewater treatment plants (WWTPs). This study aimed to (1) examine the co-treatment of leachate with a 5-day biochemical oxygen demand (BOD5): chemical oxygen demand (COD) ratio less than or slightly greater than 0.26 (intermediate age leachate) in municipal WWTPs (2) quantify the maximum hydraulic and mass (expressed as mass nitrogen or COD) loading of landfill leachate (as a percentage of the total influent loading rate) above which the performance of a WWTP may be inhibited, and (3) quantify the impact of a range of hydraulic loading rates (HLRs) of young and intermediate age leachate, loaded on a volumetric basis at 0 (study control), 2, 4 and 10% (volume landfill leachate influent as a percentage of influent municipal wastewater), on the effluent ammonium concentrations. The leachate loading regimes examined were found to be appropriate for effective treatment of intermediate age landfill leachate in the WWTPs examined, but co-treatment may not be suitable in WWTPs with low ammonium-nitrogen (NH4-N) and total nitrogen (TN) emission limit values (ELVs). In addition, intermediate leachate, loaded at volumetric rates of up to 4% or 50% of total WWTP NH4-N loading, did not significantly inhibit the nitrification processes, while young leachate, loaded at volumetric rates greater of than 2% (equivalent to 90% of total WWTP NH4-N loading), resulted in a significant decrease in nitrification. The results show that current hydraulic loading-based acceptance criteria recommendations should be considered in the context of leachate NH4-N composition. The results also indicate that co-treatment of old leachate in municipal WWTPs may represent the most sustainable solution

  7. Oxygen-controlled biosurfactant production in a bench scale bioreactor.

    PubMed

    Kronemberger, Frederico de Araujo; Santa Anna, Lidia Maria Melo; Fernandes, Ana Carolina Loureiro Brito; Menezes, Reginaldo Ramos de; Borges, Cristiano Piacsek; Freire, Denise Maria Guimarães

    2008-03-01

    Rhamnolipids have been pointed out as promising biosurfactants. The most studied microorganisms for the aerobic production of these molecules are the bacteria of the genus Pseudomonas. The aim of this work was to produce a rhamnolipid-type biosurfactant in a bench-scale bioreactor by one strain of Pseudomonas aeruginosa isolated from oil environments. To study the microorganism growth and production dependency on oxygen, a nondispersive oxygenation device was developed, and a programmable logic controller (PLC) was used to set the dissolved oxygen (DO) concentration. Using the data stored in a computer and the predetermined characteristics of the oxygenation device, it was possible to evaluate the oxygen uptake rate (OUR) and the specific OUR (SOUR) of this microorganism. These rates, obtained for some different DO concentrations, were then compared to the bacterial growth, to the carbon source consumption, and to the rhamnolipid and other virulence factors production. The SOUR presented an initial value of about 60.0 mgO(2)/g(DW) h. Then, when the exponential growth phase begins, there is a rise in this rate. After that, the SOUR reduces to about 20.0 mgO(2)/g(DW) h. The carbon source consumption is linear during the whole process.

  8. Evolution of a phase separated gravity independent bioreactor

    NASA Astrophysics Data System (ADS)

    Villeneuve, Peter E.; Dunlop, Eric H.

    The evolution of a phase-separated gravity-independent bioreactor is described. The initial prototype, a zero head-space manifold silicone membrane based reactor, maintained large diffusional resistances. Obtaining oxygen transfer rates needed to support carbon-recycling aerobic microbes is impossible if large resistances are maintained. Next generation designs (Mark I and II) mimic heat exchanger design to promote turbulence at the tubing-liquid interface, thereby reducing liquid and gas side diffusional resistances. While oxygen transfer rates increased by a factor of ten, liquid channeling prevented further increases. To overcome these problems, a Mark III reactor was developed which maintains inverted phases, i.e., media flows inside the silicone tubing, oxygen gas is applied external to the tubing. This enhances design through changes in gas side driving force concentration and liquid side turbulence levels. Combining an applied external pressure of four atmospheres with increased Reynolds numbers resulted in oxygen transfer intensities of 232 mmol O2/l/h (1000 times greater than first prototype and comparable to a conventional fermenter). A 1.0 liter Mark III reactor can potentially deliver oxygen supplies necessary to support cell cultures needed to recycle a 10 astronaut carbon load continuously.

  9. Forward osmosis membrane bioreactor for wastewater treatment with phosphorus recovery.

    PubMed

    Huang, Li-Ying; Lee, Duu-Jong; Lai, Juin-Yih

    2015-12-01

    A forward osmosis membrane bioreactor (OMBR) with a thin film composite membrane was seeded with flocculated sludge and aerobic granules to treat a synthetic wastewater with 1M NaCl as draw solution. The tested OMBR showed 96%, 43% and 100% removal of PO4(3-)-P, NH4(+)-N, and total organic carbon. Salinity was accumulated in OMBR principally owing to membrane rejection and salt leakage from draw solution. At high salinity level membrane fouling could be induced. Intermittent withdrawal and replenishment of supernatant from OMBR maintained its operation stability, while phosphorus in withdrawn supernatant was recovered by pH adjustment. The OMBR enriched phosphorus concentration from 156 mg/L in feed solution to 890-990 mg/L. At pH 8.5 with 2.65-2.71 g 3 M NaOH/g-P, 814-817 mg-P/L was recovered in the form of sodium hydrogen phosphite hydrate. The OMBR is a volatile wastewater treatment unit with capability for enrichment and recovery of phosphorus at reduced chemical costs.

  10. Oxygen-controlled Biosurfactant Production in a Bench Scale Bioreactor

    NASA Astrophysics Data System (ADS)

    de Kronemberger, Frederico Araujo; Anna, Lidia Maria Melo Santa; Fernandes, Ana Carolina Loureiro Brito; de Menezes, Reginaldo Ramos; Borges, Cristiano Piacsek; Freire, Denise Maria Guimarães

    Rhamnolipids have been pointed out as promising biosurfactants. The most studied microorganisms for the aerobic production of these molecules are the bacteria of the genus Pseudomonas. The aim of this work was to produce a rhamnolipid-type biosurfactant in a bench-scale bioreactor by one strain of Pseudomonas aeruginosa isolated from oil environments. To study the microorganism growth and production dependency on oxygen, a nondispersive oxygenation device was developed, and a programmable logic controller (PLC) was used to set the dissolved oxygen (DO) concentration. Using the data stored in a computer and the predetermined characteristics of the oxygenation device, it was possible to evaluate the oxygen uptake rate (OUR) and the specific OUR (SOUR) of this microorganism. These rates, obtained for some different DO concentrations, were then compared to the bacterial growth, to the carbon source consumption, and to the rhamnolipid and other virulence factors production. The SOUR presented an initial value of about 60.0 mg02/gdw h. Then, when the exponential growth phase begins, there is a rise in this rate. After that, the SOUR reduces to about 20.0 mg02/gdw h. The carbon source consumption is linear during the whole process.

  11. Enhancement of Nitrogen Removal in an Intermittent Aeration Membrane Bioreactor

    NASA Astrophysics Data System (ADS)

    He, Xiaojuan; Wisniewski, Christelle; Li, Xudong; Zhou, Qi

    2010-11-01

    An intermittent aerated membrane bioreactor was applied in laboratory scale to treat synthetic household wastewater. The system organic load and nitrogen load were 0.34 kgCODṡm-3ṡd-1 and 0.06 kgTNṡm-3ṡd-1, respectively. The hydraulic residence time was equal to 12 h and very long sludge residence times were imposed. Intermittent aeration, with anoxic-aerobic cycle of 30/60 minutes, was employed in the system. The results showed that 100% SS and >90% COD could be removed. The average removal efficiency of NH4-N and TN was 99.7% and 80%, respectively. A linear relationship between the fouling rate and the MLSS, MLVSS concentration was founded. The denitrification seemed to be the rate-limiting step for nitrogen removal. To enhance denitrification, the following strategies could be considered: 1) to select suitable aeration/non-aeration cycle, 2) to control the aeration intensity, 3) to feed the system at the beginning of non-aeration period, 4) to maintain high MLSS concentration.

  12. Evolution of a phase separated gravity independent bioreactor

    NASA Technical Reports Server (NTRS)

    Villeneuve, Peter E.; Dunlop, Eric H.

    1992-01-01

    The evolution of a phase-separated gravity-independent bioreactor is described. The initial prototype, a zero head-space manifold silicone membrane based reactor, maintained large diffusional resistances. Obtaining oxygen transfer rates needed to support carbon-recycling aerobic microbes is impossible if large resistances are maintained. Next generation designs (Mark I and II) mimic heat exchanger design to promote turbulence at the tubing-liquid interface, thereby reducing liquid and gas side diffusional resistances. While oxygen transfer rates increased by a factor of ten, liquid channeling prevented further increases. To overcome these problems, a Mark III reactor was developed which maintains inverted phases, i.e., media flows inside the silicone tubing, oxygen gas is applied external to the tubing. This enhances design through changes in gas side driving force concentration and liquid side turbulence levels. Combining an applied external pressure of 4 atm with increased Reynolds numbers resulted in oxygen transfer intensities of 232 mmol O2/l per hr (1000 times greater than the first prototype and comparable to a conventional fermenter). A 1.0 liter Mark III reactor can potentially deliver oxygen supplies necessary to support cell cultures needed to recycle a 10-astronaut carbon load continuously.

  13. EVALUATION OF COLLIER COUNTY, FLORIDA LANDFILL MINING DEMONSTRATION

    EPA Science Inventory

    This report describes the landfill mining process as demonstrated under the U.S. EPA, Risk Reduction Engineering Laboratory's Municipal Waste Innovative Technology Evaluation (MITE) Program by the Collier County (Florida) Solid Waste Management Department. Landfill mining is the ...

  14. Using landfill gas for energy: Projects that pay

    SciTech Connect

    1995-02-01

    Pending Environmental Protection Agency regulations will require 500 to 700 landfills to control gas emissions resulting from decomposing garbage. Conversion of landfill gas to energy not only meets regulations, but also creates energy and revenue for local governments.

  15. 40 CFR 761.75 - Chemical waste landfills.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... landfill do not exceed 500 ppm PCB and measures to prevent the migration of PCBs from the landfill. Bulk... shall be placed around the site to prevent unauthorized persons and animals from entering. (ii)...

  16. Quantifying Uncontrolled Air Emissions from Two Florida Landfills

    EPA Science Inventory

    Landfill gas emissions, if left uncontrolled, contribute to air toxics, climate change, trospospheric ozone, and urban smog. Measuring emissions from landfills presents unique challenges due to the large and variable source area, spatial and temporal variability of emissions, and...

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

    PubMed

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

    2015-07-01

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

  18. Landfills as a biorefinery to produce biomass and capture biogas.

    PubMed

    Bolan, N S; Thangarajan, R; Seshadri, B; Jena, U; Das, K C; Wang, H; Naidu, R

    2013-05-01

    While landfilling provides a simple and economic means of waste disposal, it causes environmental impacts including leachate generation and greenhouse gas (GHG) emissions. With the introduction of gas recovery systems, landfills provide a potential source of methane (CH4) as a fuel source. Increasingly revegetation is practiced on traditionally managed landfill sites to mitigate environmental degradation, which also provides a source of biomass for energy production. Combustion of landfill gas for energy production contributes to GHG emission reduction mainly by preventing the release of CH4 into the atmosphere. Biomass from landfill sites can be converted to bioenergy through various processes including pyrolysis, liquefaction and gasification. This review provides a comprehensive overview on the role of landfills as a biorefinery site by focusing on the potential volumes of CH4 and biomass produced from landfills, the various methods of biomass energy conversion, and the opportunities and limitations of energy capture from landfills.

  19. Artificial sweeteners as potential tracers of municipal landfill leachate.

    PubMed

    Roy, James W; Van Stempvoort, Dale R; Bickerton, Greg

    2014-01-01

    Artificial sweeteners are gaining acceptance as tracers of human wastewater in the environment. The 3 artificial sweeteners analyzed in this study were detected in leachate or leachate-impacted groundwater at levels comparable to those of untreated wastewater at 14 of 15 municipal landfill sites tested, including several closed for >50 years. Saccharin was the dominant sweetener in old (pre-1990) landfills, while newer landfills were dominated by saccharin and acesulfame (introduced 2 decades ago; dominant in wastewater). Cyclamate was also detected, but less frequently. A case study at one site illustrates the use of artificial sweeteners to identify a landfill-impacted groundwater plume discharging to a stream. The study results suggest that artificial sweeteners can be useful tracers for current and legacy landfill contamination, with relative abundances of the sweeteners potentially providing diagnostic ability to distinguish different landfills or landfill cells, including crude age-dating, and to distinguish landfill and wastewater sources.

  20. Open source software to control Bioflo bioreactors.

    PubMed

    Burdge, David A; Libourel, Igor G L

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW.

  1. Soil gas investigations at the Sanitary Landfill

    SciTech Connect

    Wyatt, D.E.; Pirkle, R.J.; Masdea, D.J.

    1992-07-01

    A soil gas survey was performed at the 740-G Sanitary Landfill of Savannah River Plant during December, 1990. The survey monitored the presence and distribution of the C[sub 1]C[sub 4] hydrocarbons; the C[sub 5]-C[sub 10] normal paraffins; the aromatic hydrocarbons, BTXE; selected chlorinated hydrocarbons; and mercury. Significant levels of several of these contaminants were found associated with the burial site. In the northern area of the Landfill, methane concentrations ranged up to 63% of the soil gas and were consistently high on the western side of the access road. To the east of the access road in the northern and southern area high concentrations of methane were encountered but were not consistently high. Methane, the species found in highest concentration in the landfill, was generated in the landfill as the result of biological oxidation of cellulose and other organics to carbon dioxide followed by reduction of the carbon dioxide to methane. Distributions of other species are the result of burials in the landfill of solvents or other materials.

  2. Soil gas investigations at the Sanitary Landfill

    SciTech Connect

    Wyatt, D.E.; Pirkle, R.J.; Masdea, D.J.

    1992-07-01

    A soil gas survey was performed at the 740-G Sanitary Landfill of Savannah River Plant during December, 1990. The survey monitored the presence and distribution of the C{sub 1}C{sub 4} hydrocarbons; the C{sub 5}-C{sub 10} normal paraffins; the aromatic hydrocarbons, BTXE; selected chlorinated hydrocarbons; and mercury. Significant levels of several of these contaminants were found associated with the burial site. In the northern area of the Landfill, methane concentrations ranged up to 63% of the soil gas and were consistently high on the western side of the access road. To the east of the access road in the northern and southern area high concentrations of methane were encountered but were not consistently high. Methane, the species found in highest concentration in the landfill, was generated in the landfill as the result of biological oxidation of cellulose and other organics to carbon dioxide followed by reduction of the carbon dioxide to methane. Distributions of other species are the result of burials in the landfill of solvents or other materials.

  3. Nitrogen Removal from Landfill Leachate by Microalgae

    PubMed Central

    Pereira, Sérgio F. L.; Gonçalves, Ana L.; Moreira, Francisca C.; Silva, Tânia F. C. V.; Vilar, Vítor J. P.; Pires, José C. M.

    2016-01-01

    Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates. PMID:27869676

  4. Hydrogeology of a landfill, Pinellas County, Florida

    USGS Publications Warehouse

    Fernandez, Mario

    1983-01-01

    The Pinellas County landfill site is on a flat, coastal area characterized by a high water table is subject to tidal flooding. Altitudes within the study area range from 8 to 12 feet above sea level. Three geohydrologic units underlie the landfill site: a surficial aquifer about 19 feet thick composed of sand and shells; a confining bed about 35 feet thick composed of marl and clay; and the Floridan aquifer composed of limestone. The rate of lateral movement of ground water away from the site is about 1.2 feet per year; however, the rate of movement along the boundary of the landfill cells is about 20 feet per year. Vertical movement through the confining layer is about 0.005 foot per year. Landfill operations have not altered surface-water quality. Leachate migration downward into the Floridan aquifer is not indicated, but data do indicate leachate is migrating from the oldest section of the landfill site through the surficial aquifer. Peaks in concentration of selected chemical parameters and flow-rate analysis of water from trenches indicate the possibility of slug-flow leachate. (USGS)

  5. Economic and environmental sustainability of submerged anaerobic MBR-based (AnMBR-based) technology as compared to aerobic-based technologies for moderate-/high-loaded urban wastewater treatment.

    PubMed

    Pretel, R; Robles, A; Ruano, M V; Seco, A; Ferrer, J

    2016-01-15

    The objective of this study was to assess the economic and environmental sustainability of submerged anaerobic membrane bioreactors (AnMBRs) in comparison with aerobic-based technologies for moderate-/high-loaded urban wastewater (UWW) treatment. To this aim, a combined approach of steady-state performance modelling, life cycle analysis (LCA) and life cycle costing (LCC) was used, in which AnMBR (coupled with an aerobic-based post-treatment) was compared to aerobic membrane bioreactor (AeMBR) and conventional activated sludge (CAS). AnMBR with CAS-based post-treatment for nutrient removal was identified as a sustainable option for moderate-/high-loaded UWW treatment: low energy consumption and reduced sludge production could be obtained at given operating conditions. In addition, significant reductions can be achieved in different aspects of environmental impact (global warming potential (GWP), abiotic depletion, acidification, etc.) and LCC over existing UWW treatment technologies.

  6. Appendix E: Research papers. Analysis of landfills with historic airphotos

    NASA Technical Reports Server (NTRS)

    Liang, T.; Philipson, W. R. (Principal Investigator); Erb, T. L.; Teng, W. L.

    1980-01-01

    The nature of landfill-related information that can be derived from existing, or historic, aerial photographs, is reviewed. This information can be used for conducting temporal assessments of landfill existence, land use and land cover, and the physical environment. As such, analysis of low cost, readily available aerial photographs can provide important, objective input to landfill inventories, assessing contamination or health hazards, planning corrective measures, planning waste collection and facilities, and developing on inactive landfills.

  7. FIRST ORDER KINETIC GAS GENERATION MODEL PARAMETERS FOR WET LANDFILLS

    EPA Science Inventory

    Landfill gas is produced as a result of a sequence of physical, chemical, and biological processes occurring within an anaerobic landfill. Landfill operators, energy recovery project owners, regulators, and energy users need to be able to project the volume of gas produced and re...

  8. ESTIMATE OF METHANE EMISSIONS FROM U.S. LANDFILLS

    EPA Science Inventory

    The report describes the development of a statistical regression model used for estimating methane (CH4) emissions, which relates landfill gas (LFG) flow rates to waste-in-place data from 105 landfills with LFG recovery projects. (NOTE: CH4 flow rates from landfills with LFG reco...

  9. A nanoliter microfluidic serial dilution bioreactor

    PubMed Central

    Gu, Guo-Yue; Lee, Yi-Wei; Chiang, Chih-Chung; Yang, Ya-Tang

    2015-01-01

    Bacterial culture is a basic technique in both fundamental and applied microbiology. The excessive reagent consumption and laborious maintenance of bulk bioreactors for microbial culture have prompted the development of miniaturized on-chip bioreactors. With the minimal choice of two compartments (N = 2) and discrete time, periodic dilution steps, we realize a microfluidic bioreactor that mimics macroscopic serial dilution transfer culture. This device supports automated, long-term microbial cultures with a nanoliter-scale working volume and real-time monitoring of microbial populations at single-cell resolution. Because of the high surface-to-volume ratio, the device also operates as an effective biofilm-flow reactor to support cogrowth of planktonic and biofilm populations. We expect that such devices will open opportunities in many fields of microbiology. PMID:26392828

  10. Design concepts for bioreactors in space

    NASA Technical Reports Server (NTRS)

    Seshan, P. K.; Peterson, G. R.; Beard, B.; Dunlop, E. H.

    1986-01-01

    Microbial food sources are becoming viable and more efficient alternatives to conventional food sources especially in the context of Closed Ecological Life Support Systems (CELSS) in space habitats. Since bioreactor designs for terrestrial operation will not readily apply to conditions of microgravity, there is an urgent need to learn about the differences. These differences cannot be easily estimated due to the complex nature of the mass transport and mixing mechanisms in fermenters. Therefore, a systematic and expeditious experimental program must be undertaken to obtain the engineering data necessary to lay down the foundations of designing bioreactors for microgravity. Two bioreactor design concepts presented represent two dissimilar approaches to grappling with the absence of gravity in space habitats and deserve to be tested for adoption as important components of the life support function aboard spacecrafts, space stations and other extra-terrestrial habitats.

  11. US EPA record of decision review for landfills: Sanitary landfill (740-G), Savannah River Site

    SciTech Connect

    Not Available

    1993-06-01

    This report presents the results of a review of the US Environmental Protection Agency (EPA) Record of Decision System (RODS) database search conducted to identify Superfund landfill sites where a Record of Decision (ROD) has been prepared by EPA, the States or the US Army Corps of Engineers describing the selected remedy at the site. ROD abstracts from the database were reviewed to identify site information including site type, contaminants of concern, components of the selected remedy, and cleanup goals. Only RODs from landfill sites were evaluated so that the results of the analysis can be used to support the remedy selection process for the Sanitary Landfill at the Savannah River Site (SRS).

  12. Landfill stabilization focus area: Technology summary

    SciTech Connect

    1995-06-01

    Landfills within the DOE Complex as of 1990 are estimated to contain 3 million cubic meters of buried waste. The DOE facilities where the waste is predominantly located are at Hanford, the Savannah River Site (SRS), the Idaho National Engineering Laboratory (INEL), the Los Alamos National Laboratory (LANL), the Oak Ridge Reservation (ORR), the Nevada Test Site (NTS), and the Rocky Flats Plant (RFP). Landfills include buried waste, whether on pads or in trenches, sumps, ponds, pits, cribs, heaps and piles, auger holes, caissons, and sanitary landfills. Approximately half of all DOE buried waste was disposed of before 1970. Disposal regulations at that time permitted the commingling of various types of waste (i.e., transuranic, low-level radioactive, hazardous). As a result, much of the buried waste throughout the DOE Complex is presently believed to be contaminated with both hazardous and radioactive materials. DOE buried waste typically includes transuranic-contaminated radioactive waste (TRU), low-level radioactive waste (LLW), hazardous waste per 40 CFR 26 1, greater-than-class-C waste per CFR 61 55 (GTCC), mixed TRU waste, and mixed LLW. The mission of the Landfill Stabilization Focus Area is to develop, demonstrate, and deliver safer,more cost-effective and efficient technologies which satisfy DOE site needs for the remediation and management of landfills. The LSFA is structured into five technology areas to meet the landfill remediation and management needs across the DOE complex. These technology areas are: assessment, retrieval, treatment, containment, and stabilization. Technical tasks in each of these areas are reviewed.

  13. Greenhouse gas emissions from two-stage landfilling of municipal solid waste

    NASA Astrophysics Data System (ADS)

    Zhang, Yuanyuan; Yue, Dongbei; Nie, Yongfeng

    2012-08-01

    Simulations were conducted to investigate greenhouse gas emissions from aerobic pretreatment and subsequent landfilling. The flows in carbon balance, such as gas, leachate, and solid phases, were considered in the simulations. The total amount of CO2 eq. decreased as organic removal efficiency (ORE) increased. At ORE values of 0, 0.30, 0.41, and 0.54, the total amounts of CO2 eq. were 2614, 2326, 2075, and 1572 kg CO2 eq. per one ton dry matter, respectively; gas accounted for the main contribution to the total amount. The reduction in CO2 eq. from leachate was the primary positive contribution, accounting for 356%, 174%, and 100% of total reduction at ORE values of 0.30, 0.41, and 0.54, respectively. The CO2 eq. from energy consumption was the negative contribution to total reduction, but this contribution is considerably lower than that from gas. Aerobic pretreatment shortened the lag time of biogas production by 74.1-97.0%, and facilitated the transfer of organic carbon in solid waste from uncontrolled biogas and highly polluting leachate to aerobically generated CO2.

  14. Performance and completion assessment of an in-situ aerated municipal solid waste landfill - Final scientific documentation of an Austrian case study.

    PubMed

    Hrad, Marlies; Huber-Humer, Marion

    2016-08-23

    By converting anaerobic landfills into a biologically stabilized state through accelerating aerobic organic matter degradation, the effort and duration necessary for post-closure procedures can be shortened. In Austria, the first full-scale application of in-situ landfill aeration by means of low pressure air injection with simultaneous off-gas collection and treatment was implemented on an old MSW-landfill and operated between 2007 and 2013. Besides complementary laboratory investigations, which included waste sampling from the landfill site prior to aeration start, a comprehensive field monitoring program was conducted to assess the influence of the aeration measure on the emission behavior of the landfilled waste during the aeration period as well as after aeration completion. Although the initial waste material was described as rather stable, the lab-scale aeration tests indicated a significant improvement of the leachate quality and even the biological solid waste stability. However, the aeration success was less pronounced for the application at the landfill site, mainly due to technical limitations in the full-scale operation. In this paper main performance data of the field investigation are compared to four other scientifically documented case studies along with stability indicators for solid waste and leachate characteristics in order to evaluate the success of aeration as well as the progress of a landfill towards completion and end of post-closure care. A number of quantitative benchmarks and relevant context information for the performance assessment of the five hitherto conducted international aeration projects are proposed aiming to support the systematization and harmonization of available results from diverse field studies and full-scale applications in future.

  15. Landfill gas boosted to pipeline quality

    SciTech Connect

    Not Available

    1984-03-01

    The world's largest landfill recovery facility, located on Staten Island, went on stream in 1982 and is expected to produce 1.3 billion CF/yr of pipeline gas. Containing 45% carbon dioxide, the gas is compressed and cooled in stages to meet the requirements of the Selexol purification plant. Two 1120-kW (1500-hp) Copper Bessemer GMVS-8C integral gas engine-compressors, fueled by the landfill gas, provide the compression needed from the wells to the final solvent-contact stage.

  16. Development of a Space Bioreactor using Microtechnology

    NASA Technical Reports Server (NTRS)

    Arquint, Philippe; Boillat, Marc A.; deRooij, Nico F.; Jeanneret, Sylvain; vanderSchoot, Bart H.; Bechler, Birgitt; Cogoli, Augusto; Walther, Isabelle; Gass, Volker; Ivorra, Marie-Therese

    1995-01-01

    A miniature bio-reactor for the cultivation of cells aboard Spacelab is presented. Yeast cells are grown in a 3 milliliter reactor chamber. A supply of fresh nutrient medium is provided by a piezo-electric silicon micro-pump. In the reactor, pH, temperature, and redox potential are monitored and the pH is regulated at a constant value. The complete instrument is fitted in a standard experiment container of 63 x 63 x 85 mm. The bioreactor was used on the IML-2 mission in July 1994 and is being refurbished for a reflight in the spring of 1996.

  17. Bioreactor and methods for producing synchronous cells

    NASA Technical Reports Server (NTRS)

    Helmstetter, Charles E. (Inventor); Thornton, Maureen (Inventor); Gonda, Steve (Inventor)

    2005-01-01

    Apparatus and methods are directed to a perfusion culture system in which a rotating bioreactor is used to grow cells in a liquid culture medium, while these cells are attached to an adhesive-treated porous surface. As a result of this arrangement and its rotation, the attached cells divide, with one cell remaining attached to the substrate, while the other cell, a newborn cell is released. These newborn cells are of approximately the same age, that are collected upon leaving the bioreactor. The populations of newborn cells collected are of synchronous and are minimally, if at all, disturbed metabolically.

  18. Microbial community analysis of an aerobic nitrifying-denitrifying MBR treating ABS resin wastewater.

    PubMed

    Chang, Chia-Yuan; Tanong, Kulchaya; Xu, Jia; Shon, Hokyong

    2011-05-01

    A two-stage aerobic membrane bioreactor (MBR) system for treating acrylonitrile butadiene styrene (ABS) resin wastewater was carried out in this study to evaluate the system performance on nitrification. The results showed that nitrification of the aerobic MBR system was significant and the highest TKN removal of approximately 90% was obtained at hydraulic retention time (HRT) 18 h. In addition, the result of nitrogen mass balance revealed that the percentage of TN removal due to denitrification was in the range of 8.7-19.8%. Microbial community analysis based on 16s rDNA molecular approach indicated that the dominant ammonia oxidizing bacteria (AOB) group in the system was a β-class ammonia oxidizer which was identified as uncultured sludge bacterium (AF234732). A heterotrophic aerobic denitrifier identified as Thauera mechernichensis was found in the system. The results indicated that a sole aerobic MBR system for simultaneous removals of carbon and nitrogen can be designed and operated for neglect with an anaerobic unit.

  19. Membrane bioreactors for water reclamation.

    PubMed

    Tao, G; Kekre, K; Wei, Z; Lee, T C; Viswanath, B; Seah, H

    2005-01-01

    Singapore has been using dual membrane technology (MF/UF RO) to produce high-grade water (NEWater) from secondary treated sewage. Membrane bioreactor (MBR) has very high potential and will lead to the further improvement of the productivity and quality of high-grade water. This study was focused on the technical feasibility of MBR system for water reclamation in Singapore, making a comparison between various membrane systems available and to get operational experience in terms of membrane cleaning and other issues. Three MBR plants were built at Bedok Water Reclamation Plant with a design flow of 300 m3/day each. They were commissioned in March 2003. Three different types of submerged membranes were tested. They are Membrane A, plate sheet membrane with pore size of 0.4 microm; Membrane B, hollow fibre membrane with pore size of 0.4 microm; and Membrane C, hollow fibre membrane with pore size of 0.035 microm. The permeate quality of all the three MBR Systems were found equivalent to or better than that of the conventional tertiary treatment by ultrafiltration. MBR permeate TOC was about 2 mg/l lower than UF permeate TOC. GC-MS, GC-ECD and HPLC scan results show that trace organic contaminants in MBR permeate and UF permeate were in the same range. MBR power consumption can be less than 1 kwh/m3. Gel layer or dynamic membrane generated on the submerged membrane surface played an important role for the lower MBR permeate TOC than the supernatant TOC in the membrane tank. Intensive chemical cleaning can temporarily remove this layer. During normal operation conditions, the formation of dynamic membrane may need one day to obtain the steady low TOC levels in MBR permeate.

  20. Designing systems for landfill gas migration control in Minnesota

    SciTech Connect

    Cannon, J.

    1996-11-01

    Camp, Dresser & McKee (CDM) has designed or is in the process of designing several landfill gas migration control systems in Minnesota. The systems are for both active and closed municipal solid waste landfills. The sites have a variety of covers, including geomembranes, clay caps, and non-engineered soil covers. The control system types include small perimeter systems, full-site systems and phased systems for active sites. Figure 1 shows the locations of the systems CDM is working on in Minnesota. This paper focuses on four sites: Oak Grove Landfill, Hopkins Landfill, Washington County Landfill, and Elk River Landfill. Table 1 provides an outline of the individual site characteristics. The first three sites are closed landfills. The Oak Grove Landfill system was designed and constructed for a group of industries responsible for closure and remedial action. The Hopkins and Washington County landfills are under the control of the Minnesota Pollution Control Agency (MPCA). The MPCA enacted a remedial action program at closed landfills, taking over responsibility for long-term liability under the terms of legally binding agreements negotiated with the site owners. The Elk River Landfill is an active, privately-owned facility. The migration problems and solutions developed for these four landfills are generally descriptive of all the landfills CDM is working on in Minnesota. All landfills have unique characteristics requiring site-specific solutions. CDM, after designing a number of migration control systems in Minnesota, is able to provide a generalized description of design options for specific types of sites. This paper discussions design options used to address different cover types, aesthetic needs, and waste depths, and includes a discussion of design needs for cold climates. A brief case history of the Oak Grove Landfill is included.

  1. Effect of hydraulic retention time and sludge recirculation on greenhouse gas emission and related microbial communities in two-stage membrane bioreactor treating solid waste leachate.

    PubMed

    Nuansawan, Nararatchporn; Boonnorat, Jarungwit; Chiemchaisri, Wilai; Chiemchaisri, Chart

    2016-06-01

    Methane (CH4) and nitrous oxide (N2O) emissions and responsible microorganisms during the treatment of municipal solid waste leachate in two-stage membrane bioreactor (MBR) was investigated. The MBR system, consisting of anaerobic and aerobic stages, were operated at hydraulic retention time (HRT) of 5 and 2.5days in each reactor under the presence and absence of sludge recirculation. Organic and nitrogen removals were more than 80% under all operating conditions during which CH4 emission were found highest under no sludge recirculation condition at HRT of 5days. An increase in hydraulic loading resulted in a reduction in CH4 emission from anaerobic reactor but an increase from the aerobic reactor. N2O emission rates were found relatively constant from anaerobic and aerobic reactors under different operating conditions. Diversity of CH4 and N2O producing microorganisms were found decreasing when hydraulic loading rate to the reactors was increased.

  2. Three-dimensional culture and bioreactors for cellular therapies.

    PubMed

    Naing, M W; Williams, D J

    2011-04-01

    A bioreactor is defined as a specifically designed vessel to facilitate the growth of organisms and cells through application of physical and/or electrical stimulus. When cells with therapeutic potential were first discovered, they were initially cultured and expanded in two-dimensional (2-D) culture vessels such as plates or T-flasks. However, it was soon discovered that bioreactors could be used to expand and maintain cultures more easily and efficiently. Since then, bioreactors have come to be accepted as an indispensable tool to advance cell and tissue culture further. A wide array of bioreactors has been developed to date, and in recent years businesses have started supplying bioreactors commercially. Bioreactors in the research arena range from stirred tank bioreactors for suspension culture to those with various mechanical actuators that can apply different fluidic and mechanical stresses to tissues and three-dimensional (3-D) scaffolds. As regenerative medicine gains more traction in the clinic, bioreactors for use with cellular therapies are being developed and marketed. While many of the simpler bioreactors are fit for purpose, others fail to satisfy the complex requirements of tissues in culture. We have examined the use of different types of bioreactors in regenerative medicine and evaluated the application of bioreactors in the realization of emerging cellular therapies.

  3. Methane Gas Utilization Project from Landfill at Ellery (NY)

    SciTech Connect

    Pantelis K. Panteli

    2012-01-10

    Landfill Gas to Electric Energy Generation and Transmission at Chautauqua County Landfill, Town of Ellery, New York. The goal of this project was to create a practical method with which the energy, of the landfill gas produced by the decomposing waste at the Chautauqua County Landfill, could be utilized. This goal was accomplished with the construction of a landfill gas to electric energy plant (originally 6.4MW and now 9.6MW) and the construction of an inter-connection power-line, from the power-plant to the nearest (5.5 miles) power-grid point.

  4. [Odor pollution from landfill sites and its control: a review].

    PubMed

    Hu, Bin; Ding, Ying; Wu, Wei-Xiang; Hu, Bei-Gang; Chen, Ying-Xu

    2010-03-01

    Landfill sites are the major sources of offensive odor in urban public facilities. With the progress of urbanization and the residents' demands for a higher living environment quality, the odor emission from landfill sites has become a severe pollution problem, and the odor control at landfill sites has been one of the research hotspots. This paper summarized the main components and their concentrations of the odor from landfill sites, and expatiated on the research progress in the in-situ control of the odor. The further research directions in in-situ control of the odor from landfill sites were prospected.

  5. Techniques for modeling hazardous air pollutant emissions from landfills

    SciTech Connect

    Lang, R.J.; Vigil, S.A.; Melcer, H.

    1998-12-31

    The Environmental Protection Agency`s Landfill Air Estimation Model (LAEEM), combined with either the AP-42 or CAA landfill emission factors, provide a basis to predict air emissions, including hazardous air pollutants (HAPs), from municipal solid waste landfills. This paper presents alternative approaches for estimating HAP emissions from landfills. These approaches include analytical solutions and estimation techniques that account for convection, diffusion, and biodegradation of HAPs. Results from the modeling of a prototypical landfill are used as the basis for discussion with respect to LAEEM results

  6. Back-Analyses of Landfill Instability Induced by High Water Level: Case Study of Shenzhen Landfill.

    PubMed

    Peng, Ren; Hou, Yujing; Zhan, Liangtong; Yao, Yangping

    2016-01-12

    In June 2008, the Shenzhen landfill slope failed. This case is used as an example to study the deformation characteristics and failure mode of a slope induced by high water levels. An integrated monitoring system, including water level gauges, electronic total stations, and inclinometers, was used to monitor the slope failure process. The field measurements suggest that the landfill landslide was caused by a deep slip along the weak interface of the composite liner system at the base of the landfill. The high water level is considered to be the main factor that caused this failure. To calculate the relative interface shear displacements in the geosynthetic multilayer liner system, a series of numerical direct shear tests were carried out. Based on the numerical results, the composite lining system simplified and the centrifuge modeling technique was used to quantitatively evaluate the effect of water levels on landfill instability.

  7. Back-Analyses of Landfill Instability Induced by High Water Level: Case Study of Shenzhen Landfill

    PubMed Central

    Peng, Ren; Hou, Yujing; Zhan, Liangtong; Yao, Yangping

    2016-01-01

    In June 2008, the Shenzhen landfill slope failed. This case is used as an example to study the deformation characteristics and failure mode of a slope induced by high water levels. An integrated monitoring system, including water level gauges, electronic total stations, and inclinometers, was used to monitor the slope failure process. The field measurements suggest that the landfill landslide was caused by a deep slip along the weak interface of the composite liner system at the base of the landfill. The high water level is considered to be the main factor that caused this failure. To calculate the relative interface shear displacements in the geosynthetic multilayer liner system, a series of numerical direct shear tests were carried out. Based on the numerical results, the composite lining system simplified and the centrifuge modeling technique was used to quantitatively evaluate the effect of water levels on landfill instability. PMID:26771627

  8. Test methods to aid in the evaluation of the diversion of biodegradable municipal waste (BMW) from landfill.

    PubMed

    Sánchez, Antoni

    2009-08-01

    This discussion explores one crucial point about the use of biodegradability indicators to monitor biological processes in organic solid waste treatment plants. Today, some different measures are being used for the determination of biodegradable organic matter and most of them are based on respiration indices (oxygen consumption or carbon dioxide production under aerobic conditions) or biogas production tests (under strict anaerobic conditions). However, it is not evident from scientific literature that both tests may be equivalent or comparable. This discussion includes the results obtained when trying to correlate both anaerobic and aerobic tests to complement the recent work published by Wagland et al. [Wagland, S.T., Tyrrel, S.F., Godley, A.R., Smith, R., 2009. Test methods to aid in the evaluation of the diversion of biodegradable municipal waste (BMW) from landfill. Waste Management 29, 1218-1226].

  9. Die aerobe Glykolyse der Tumorzelle

    NASA Astrophysics Data System (ADS)

    Schneider, Friedhelm

    1981-01-01

    A high aerobic glycolysis (aerobic lactate production) is the most significant feature of the energy metabolism of rapidly growing tumor cells. Several mechanisms, which may be different in different cell lines, seem to be involved in this characteristic of energy metabolism of the tumor cell. Changes in the cell membrane leading to increased uptake and utilization of glucose, a high level of fetal types of isoenzymes, a decreased number of mitochondria and a reduced capacity to metabolize pyruvate are some factors which must be taken into consideration. It is not possible to favour one of them at the present time.

  10. Landfill gas energy recovery: Turning a liability into an asset

    SciTech Connect

    Nichols, M.

    1996-08-01

    Until the past decade, landfill gas (LFG) was viewed as a nuisance at best and a hazard at worst. Today, municipalities and private-sector solid waste management companies are findings ways to put landfill gas to productive use. Landfill gas energy recovery eliminates detrimental air emissions; prevents landfill methane from contributing to global climate change; stops methane from migrating off-site and becoming a safety hazard or odor problem; and provides local utilities, industry, and consumers with a competitive, local source of power. In other words, LFG-to-energy facilities provide a unique form of recycling--solid waste is hauled to the landfill as refuse and returned to the consumer in the form of energy. US EPA`s Landfill Methane Outreach Program (LMOP) and new EPA regulations for control of landfill gas emissions work together to encourage greater use of LFT at many facilities across the US.

  11. Implementing landfill surfaces methane monitoring for the municipal solid waste landfill NSPS/EG

    SciTech Connect

    Huitric, R.; Banaji, J.

    1996-11-01

    The United States Environmental Protection Agency`s (USEPA) Municipal Solid Waste Landfill New Source Performance Standard (NSPS) and Emission Guidelines (EG) implements a landfill surface methane performance standard to verify emissions control effectiveness. The standard requires that periodic measures of surface gases along a predesignated route be less than 500 ppm methane at any point. During rule proposal, SWANA`s Landfill Gas Management Division (LFGMD) had advocated a performance standard as a more economic and effective alternative to the very prescriptive requirements first proposed by the USEPA in 1991. However, LFGMD recommended an averaged rather than a point source measure of the surface gases. Under the final NSPS rule, the landfill surface gas must be tested along the landfill`s perimeter and along interior routes each quarter. The interior routes must be aligned such that no route portion is more than 30 meters from any other portion. Exemptions are allowed for hazardous areas. A portable methane detector meeting USEPA`s Method 21 requirements is used to continuously sample air pumped from a probe or wand placed between 5 and 10 centimeters of the ground surface as a technician walks along a route. This paper addresses various implementation issues and discusses the development of possible monitoring alternatives, as allowed by the rule.

  12. Soil contaminations in landfill: a case study of the landfill in Czech Republic

    NASA Astrophysics Data System (ADS)

    Adamcová, D.; Vaverková, M. D.; Bartoň, S.; Havlíček, Z.; Břoušková, E.

    2015-10-01

    Phytotoxicity test was determined to assess ecotoxicity of landfill soil. Sinapis alba L. was used as heavy metals bioindicator. Soil samples 1-8, which were taken from the landfill body, edge of the landfill body and its vicinity meet the limits for heavy metals Co, Cd, Pb, and Zn specified in the applicable legislation. Hg and Mn threshold values are not established in legislation, but values have been determined for the needs of the landfill operator. For heavy metals Cr, Cu, and Ni sample 2 exceeded the threshold values, which attained the highest values of all the samples tested for Cr, Cu and Ni. For Cr and Ni the values were several times higher than values of the other samples. The second highest values for Cr, Cu, and Ni showed sample 6 and 7. Both samples exceeded the set limits. An increase in plant biomass was observed in plants growing on plates with soil samples, but no changes in appearance, slow growth or necrotic lesions appeared. Ecotoxicity tests show that tested soils (concentration of 50 %) collected from the landfill body, edge of the landfill body and its vicinity reach high percentage values of germination capacity of seeds of Sinapis alba L. (101-137 %). At a concentration of 25 %, tested soil samples exhibit lower values of germination capacity; in particular samples 3 to 8, yet the seed germination capacity in all 8 samples of tested soils range between 86 and 137 %.

  13. Soil contamination in landfills: a case study of a landfill in Czech Republic

    NASA Astrophysics Data System (ADS)

    Adamcová, D.; Vaverková, M. D.; Bartoň, S.; Havlíček, Z.; Břoušková, E.

    2016-02-01

    A phytotoxicity test was determined to assess ecotoxicity of landfill soil. Sinapis alba L. was used as a bioindicator of heavy metals. Soil samples 1-8, which were taken from the landfill body, edge of the landfill body, and its vicinity meet the limits for heavy metals Co, Cd, Pb, and Zn specified in the applicable legislation. Hg and Mn threshold values are not established in legislation, but values have been determined for the needs of the landfill operator. For heavy metals Cr, Cu, and Ni sample 2 exceeded the threshold values, which attained the highest values of all the samples tested for Cr, Cu, and Ni. For Cr and Ni the values were several times higher than values of the other samples. The second highest values for Cr, Cu, and Ni showed sample 6 and 7. Both samples exceeded the set limits. An increase in plant biomass was observed in plants growing on plates with soil samples, but no changes in appearance, slow growth, or necrotic lesions appeared. Ecotoxicity tests show that tested soils (concentration of 50 %) collected from the landfill body, edge of the landfill body, and its vicinity reach high percentage values of germination capacity of seeds of Sinapis alba L. (101-137 %). At a concentration of 25 %, tested soil samples exhibit lower values of germination capacity - in particular samples 3 to 8 - yet the seed germination capacity in all eight samples of tested soils ranges between 86 and 137 %.

  14. FUEL CELL ENERGY RECOVERY FROM LANDFILL GAS

    EPA Science Inventory

    International Fuel Cells Corporation is conducting a US Environmental Protection Agency (EPA) sponsored program to demonstrate energy recovery from landfill gas using a commercial phosphoric acid fuel cell power plant. The US EPA is interested in fuel cells for this application b...

  15. Intrinsic bioremediation of landfills interim report

    SciTech Connect

    Brigmon, R.L.; Fliermans, C.B.

    1997-07-14

    Intrinsic bioremediation is a risk management option that relies on natural biological and physical processes to contain the spread of contamination from a source. Evidence is presented in this report that intrinsic bioremediation is occurring at the Sanitary Landfill is fundamental to support incorportion into a Corrective Action Plan (CAP).

  16. EPA Facility Registry Service (FRS): LANDFILL

    EPA Pesticide Factsheets

    This web feature service contains location and facility identification information from EPA's Facility Registry Service (FRS) for the subset of non-hazardous waste sites that link to the Landfill dataset. The Landfill dataset provides detailed operating statistics, geographic locations, and facility information for waste processing and disposal operations in the United States, compiled by the Waste Business Journal, Directory of Non-Hazardous Waste Sites (Date Published: November 5th, 2007). FRS identifies and geospatially locates facilities, sites or places subject to environmental regulations or of environmental interest. Using vigorous verification and data management procedures, FRS integrates facility data from EPA's national program systems, other federal agencies, and State and tribal master facility records and provides EPA with a centrally managed, single source of comprehensive and authoritative information on facilities. This data set contains the subset of FRS integrated sites that link to the Landfill dataset once the Landfill data has been integrated into the FRS database. Additional information on FRS is available at the EPA website https://www.epa.gov/enviro/facility-registry-service-frs

  17. Colloids in the vicinity of landfills

    NASA Astrophysics Data System (ADS)

    Baumann, T.; Fruhstorfer, P.; Klein, T.; Niessner, R.

    2003-04-01

    Waste disposals without adequate landfill liner system are a source of contaminants and colloids. In order to assess the effects of the presence of colloids on the transport of heavy metal ions, the colloids at three landfill sites were characterized with regard to their chemical and mineralogical composition, their size distribution, and the concentration of heavy metal ions associated to the colloids. It can be shown that the pattern of the colloids inside and outside of the landfill is different in all examined parameters, e.g. inside of the disposal we find organic colloids and salt particles, whereas the groundwater downstream of the disposal contains mainly iron-colloids and carbonatic particles. Therefore a direct transfer of colloids from the landfill to the aquifer seems unlikely. Changes of the hydrochemical (mainly redox) and hydrodynamic conditions contribute to this behaviour. The association of heavy metal ions to colloids shows an interesting pattern: High concentrations are present in solution and associated to smaller (< 10 nm) and larger (> 1 μm) colloids, whereas the colloids in between show only small concentrations. This finding has some impact on the assessment of colloidal transport processes, since it suggests, that the more mobile colloids do not carry high concentrations of heavy metal ions.

  18. Bioreactor studies and computational fluid dynamics.

    PubMed

    Singh, H; Hutmacher, D W

    2009-01-01

    The hydrodynamic environment "created" by bioreactors for the culture of a tissue engineered construct (TEC) is known to influence cell migration, proliferation and extra cellular matrix production. However, tissue engineers have looked at bioreactors as black boxes within which TECs are cultured mainly by trial and error, as the complex relationship between the hydrodynamic environment and tissue properties remains elusive, yet is critical to the production of clinically useful tissues. It is well known in the chemical and biotechnology field that a more detailed description of fluid mechanics and nutrient transport within process equipment can be achieved via the use of computational fluid dynamics (CFD) technology. Hence, the coupling of experimental methods and computational simulations forms a synergistic relationship that can potentially yield greater and yet, more cohesive data sets for bioreactor studies. This review aims at discussing the rationale of using CFD in bioreactor studies related to tissue engineering, as fluid flow processes and phenomena have direct implications on cellular response such as migration and/or proliferation. We conclude that CFD should be seen by tissue engineers as an invaluable tool allowing us to analyze and visualize the impact of fluidic forces and stresses on cells and TECs.