https://cues.rutgers.edu/bioreactor-landfill/pdfs/02-Bensonetal2007WasteManagementBioreactorLandfillsR.pdf

Practice review of five bioreactor/recirculation landfills.

Geotechnical properties of municipal solid waste at different phases of biodegradation.

Compressibility and shear strength of municipal solid waste under short-term leachate recirculation operations.

This paper presents a laboratory investigation of hydraulic conductivity of municipal solid waste (MSW) in landfills and provides a comparative assessment of measured hydraulic conductivity values with those reported in the literature based on laboratory and field studies. A series of laboratory tests was conducted using shredded fresh and landfilled MSW from the Orchard Hills landfill (Illinois, United States) using two different small-scale and large-scale rigid-wall permeameters and a small-scale triaxial permeameter. Fresh waste was collected from the working phase, while the landfilled waste was exhumed from a borehole in a landfill cell subjected to leachate recirculation for approximately 1.5 years. The hydraulic conductivity tests conducted on fresh MSW using small-scale rigid-wall permeameter resulted in a range of hydraulic conductivity 2.8× 10−3 –11.8× 10−3  cm/s with dry unit weight varied in a narrow range between 3.9–5.1 kN/ m3 . The landfilled MSW tested using the same permeameter produced ...

Hydraulic Conductivity of MSW in Landfills

Liquid and gas permeabilities of unsaturated municipal solid waste under compression

Recently, there has been substantial interest in the enhancement of refuse decomposition in landfills, which results in increased settlement. In this paper, changes in waste compressibility as a function of the state of decomposition are reported. Samples representative of residential refuse were decomposed under conditions designed to simulate decomposition in both control and bioreactor landfills. Twenty four one-dimensional oedometer tests (63.5 mm cell) were performed on refuse prepared in laboratory-scale reactors for measurement of primary (Cc) and secondary (Ci, representing creep, and Ci, representing biological) compression indices. The state of decomposition was quantified by the methane yield and the cellulose (C) plus hemicellulose (H) to lignin (L) ratio. The magnitude of compressibility was shown to increase as refuse decomposed and compressibility parameters were correlated with the state of decomposition. Initial settlement increased with decreasing (C + H)/L ratio while the creep index was fairly independent of the state of decomposition. The coefficients of primary compression (Cc) for bioreactor samples showed an increasing trend with decreasing (C + H)/L ratios. Cc increased from 0.16 to 0.36 as (C + H)/L decreased from 1.29 to 0.25, and similar values of Cc were obtained with control samples at similar (C + H)/L ratios. The creep index range was estimated at 0.020.03 for control and bioreactor samples in various states of decomposition. The magnitude of the biological degradation index (Ci) depended on the degradation phase with the highest value of 0.19 obtained during the phase of accelerated methane production. Proposing a single Cc for landfill settlement calculations may lead to inaccurate predictions. Properties of each waste sublayer will change as a function of the decomposition stage, and dominating processes with appropriate compressibility parameters should be applied to individual sublayers.

Relationship of Compressibility Parameters to Municipal Solid Waste Decomposition

The use of resistivity imaging (RI) in subsurface investigation has increased in recent years RI is a non-destructive method and provides a continuous image of the subsurface However, only qualitative evaluation of the subsurface can be obtained from RI The correlations between RI results and geotechnical engineering properties of soils have become important for site investigation using this method The primary objective of the current study was to determine the geotechnical parameters affecting electrical resistivity of compacted clays Understanding the influential factors will be helpful in determining the correlations between RI results and geotechnical properties of soil The effects of moisture content, unit weight, degree of saturation, specific surface area, percentages of pores, and ion composition on soil resistivity were investigated Soil samples used were classified as highly plastic clay (CH) according to the Unified Soil Classification System High-energy X-ray fluorescence tests

Investigation of Geotechnical Parameters Affecting Electrical Resistivity of Compacted Clays

Bioreactor landfills are operated for rapid stabilization of waste, increased landfill gas generation for cost-effective energy recovery, gain in landfill space, enhanced leachate treatment, and reduced post closure maintenance period. The fundamental process of waste stabilization in bioreactor landfill is recirculation of generated leachate back into the landfills. This creates a favorable environment for rapid microbial decomposition of the biodegradable solid waste. In order to better estimate the generated leachate and design of leachate recirculation system, clear understanding of the permeability of the Municipal Solid Waste (MSW) with degradation and the factors influencing the permeability is necessary. The objective of the paper is to determine the changes in hydraulic properties of MSW in bioreactor landfill with time and decomposition. Four small-scale bioreactor landfills were built in laboratory and samples were prepared to represent each phase of decomposition. Then, the changes in hydraulic properties of MSW in bioreactor landfill with time and decomposition were determined. A series of constant head permeability tests were performed on the samples generated in laboratory scale bioreactor landfills to determine variation of permeability of MSW with degradation. The test results indicated that the permeability of MSW in bioreactor landfills decreases with decomposition. Based on the test results, the permeability of MSW at the first phase of degradation was estimated as 0.0088 cm/s at density 700 kg/m3. However, with degradation, permeability decreased to 0.0013 cm/s at the same density, for MSW at Phase IV.

Permeability of municipal solid waste in bioreactor landfill with degradation

The objective of this study was to characterize relative changes in waste shear strength parameters during waste decomposition Twelve direct shear tests ( 100 mm diameter by 50 mm thickness) were performed on waste specimens ranging from fresh to well-decomposed residential refuse In addition, nine direct shear tests were performed on selected waste components including fresh paper, partially decomposed refuse, and plastics Results indicate that the friction angle of refuse decreased with decomposition As refuse decomposed, the plastic content increased, which contributed to a decrease in friction angle as the friction angle of plastics is 18– 19∘ as compared to 33° for fresh shredded waste The extent of refuse decomposition was characterized by the cellulose plus hemicellulose to lignin ratio [(C+H)∕L]  The measured friction angle decreased from 32 to 24° as (C+H)∕L decreased from 129 to 025 The shearing pattern for decomposed refuse showed a peak, followed by residual, which was then followed b

M. S. Hossain

Papers

Relationship of Compressibility Parameters to Municipal Solid Waste Decomposition

Investigation of Geotechnical Parameters Affecting Electrical Resistivity of Compacted Clays

Permeability of municipal solid waste in bioreactor landfill with degradation

Shear Strength Parameters of Municipal Solid Waste with Leachate Recirculation

Prediction of Municipal Solid Waste Landfill Settlement with Leachate Recirculation