Showing papers on "Bioreactor landfill published in 1997"

Landfill bioreactor design and operation

Abstract: Introduction Scope and Objectives The Evolution of Landfills for Waste Management Landfills as Bioreactors Regulatory Status Organization of the Book Modern Landfill Fundamentals Introduction Overview of Modern Sanitary Landfills Landfill Containment Systems Collection and Control of Leachate Leachate Collection and Storage Leachate and Gas Management at MSW Landfills Landfill Operation Strategies Landfill Bioreactor Studies Laboratory Scale Studies Pilot-Scale Bioreactor Studies Full-Scale Landfill Bioreactor Studies Summary Full-Scale Experiences with Bioreactor Landfills - Case Studies Introduction Southwest Landfill, Alachua County, Florida Central Facility Landfill, Worcester County, Maryland Winfield Landfill, Columbia County, Florida Pecan Row Landfill, Lowndes County, Georgia Lower Mount Washington Valley Secure Landfill, Conway, New Hamshire Coastal Regional Solid Waste Management Authority Landfill, Craven County, North Carolina Lemons Landfill, Stoddard County, Missouri Mill Seat Landfill, Monroe County, New York Yolo County Landfill, California Additional Full-Scale Efforts The Hydrodynamics of Leachate Recirculating Landfills Introduction Leachate Generation Moisture Movement Unsaturated Leachate Flow Mathematical Modeling of Leachate Recirculation Leachate Recirculation Field Testing The Impact of Leachate Recirculation of Leachate and Gas Characteristics Introduction Leachate Characteristics of Recirculating Landfills Leachate Treatment Implications Leachate Quantities Gas Production Landfill Bioreactor Design Introduction Liner/Leachate Collection System Leachate Storage Leachate Reintroduction Systems Leachate Recirculation System Design Final and Intermediate Caps Gas Collection Cell Construction Construction Costs Summary Landfill Bioreactor Operation Introduction Waste Characterization Oxidation Reduction Conditions Moisture Content Recirculation Strategies Effects of Waste Placement Rate Use of Old Cells Bioreactor Augmentation Daily and Intermediate Covers Settlement Monitoring When is the Waste Stable? Materials Recovery and Reuse from Bioreactor Landfills Introduction Landfill Treatment and Reclamation Strategies Mass Balance Design for Landfill Reclamation Methods of Landfill Reclamation Previous Experience with Landfill Reclamation Use of Reclaimed Materials Future Directions for Bioreactor Landfills References Index

Aerobic landfill bioreactor

Abstract: 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.

Enhancing landfill leachate recirculation system performance

Abstract: Leachate recirculation is gaining popularity as an alternative to conventional single-pass leachate systems. Research has shown that leachate recirculation through a landfill can offer operational advantages such as enhanced microbiological treatment of leachate, increased landfill stabilization, and volume reduction of leachate by evaporation or absorption by refuse. Although leachate recirculation appears to be feasible as well as economically attractive, design and operational criteria have yet to be fully established and tested. This paper presents design and operations enhancements developed for the leachate recirculation system at the Kootenai County Landfill in Idaho, and describes the experience the writers have gained at other facilities.

Hydrogeological studies on the mechanical behavior of landfill gases and leachate of the Nanjido Landfill in Seoul, Korea

Abstract: The Nanjido Landfill is the largest uncontrolled landfill in Korea and it causes various kinds of environmental problems. Landfill gases and leachate are recognized as the most serious environmental problems associated with the landfill. This study employs a series of numerical models and uses test data to interpret the distribution and flow of landfill gases and leachate. Leachate seepage appears about 40–60 m higher than the estimated basal groundwater table. Thus, seepage data indicate that perched or floating leachate layers are formed in the unsaturated zone of the landfill. The leachate production rate is estimated using infiltration test data and a model for unsaturated groundwater flow. Geochemical data indicate that the landfill leachate degrades the basal groundwater quality along the downgradient zone. The environmental impact of the leachate on river water is estimated.

Organic carbon cycling in landfills: Model for a continuum approach

Abstract: Organic carbon cycling in landfills can be addressed through a continuum model where the end-points are conventional anaerobic digestion of organic waste (short-term analogue) and geologic burial of organic material (long-term analogue). Major variables influencing status include moisture state, temperature, organic carbon loading, nutrient status, and isolation from the surrounding environment. Bioreactor landfills which are engineered for rapid decomposition approach (but cannot fully attain) the anaerobic digester end-point and incur higher unit costs because of their high degree of environmental isolation and control. At the other extreme, uncontrolled land disposal of organic waste materials is similar to geologic burial where organic carbon may be aerobically recycled to atmospheric CO{sub 2}, anaerobically converted to CH{sub 4} and CO{sub 2} during early diagenesis, or maintained as intermediate or recalcitrant forms into geologic time (> 1,000 years) for transformations via kerogen pathways. A family of improved landfill models are needed at several scales (molecular to landscape) which realistically address landfill processes and can be validated with field data.

Landfill Gas As Source of VOCs in Ground Water

Abstract: During 1993 and 1994, Waste Management, Inc. and RUST Environment & Infrastructure conducted a complex site investigation at a municipal waste landfill to investigate whether landfill gas and/or leachate was the source of volatile organic chemicals (VOCs) detected in certain ground-water monitoring wells. The study was conducted in two phases. During the first phase, an investigation plan was prepared to identify VOC transport mechanisms and investigational procedures. After approval of the plan by the state regulatory agency, actual investigation and data evaluation were performed. Potential VOC transport mechanisms, including those associated with landfill gas migration, were evaluated as part of the study. Overall, investigation findings indicate that relatively broad exchanges of VOCs from landfill gas in the vadose zone to ground water exist. A much stronger correlation exists between the types of VOCs present in landfill gas and ground water than between the types of VOCs present in leachate and gro...