Computer Modelling of Landfill

This page makes available the results from a 6 year study of landfill waste disposal conducted at Oxford University. The principal investigator on the project was Dr. Alan Young then based at the Mathematical Institute.
 Funding for the work was jointly supplied by:
  • the U.K. Department of the Environment,
  • the Science and Education Research Council
  • Aspinwall and Co.Ltd
  • the U.S. Army Corps of Engineers
Two main documents resulted from this project (for contents see below) and these are supplied in PDF (use Adobe Acrobat reader) to view, and Postscript formats (use GhostView or print on a Post-script compatible laser printer).

Summary, 37 pages cwm039a (490K) cwm039a (850K)
In-depth, 197 pages (2M) cwm039b.pdf (5.3M)

If you have trouble downloading, then try an automatic helper utilty like gozilla. Please note that requests for printed copies cannot be accomodated (the project has closed and there is no budget for printing and postage).

Contents of Reports CWM039a/b

  1. Executive Summary
    1. Gas Monitoring
    2. Gas Extraction Systems
    3. Methanogenic Ecosystem
    4. Temperature and Moisture
    5. Settlement and Water Flow
    6. Summary, Recommendations and Future Work
  2. Project Background
    1. How To Read This Report
    2. History
  3. Continuum Models
    1. Introduction
    2. The General Flow Equation
    3. Slow Single Species Gas Flow
    4. Gas Extraction Wells
    5. Multiple Species Gas Flow
    6. Solute Transport
    7. Molecular Transfer between Gas and Liquid Phases
    8. Simultaneous Flow of Heat, Gas and Moisture
  4. Gas Composition and Migration
    1. Introduction
    2. Volumetric Changes Due to Atmospheric Pressure
    3. Compositional Changes Due to Atmospheric Pressure
    4. Further Work
    5. Negative Pressure Zones inside Landfills
    6. Field Investigations at Sleap Landfill
    7. Overall Conclusions on Gas Monitoring
  5. Gas Extraction Systems
    1. Introduction to Yield Reduction Coefficients
    2. Introduction to Extraction Networks
    3. Conclusion on Extraction Networks
  6. The Methanogenic Ecosystem
    1. Introduction
    2. Methodology
    3. Idealised Reactions
    4. Transport Equations
    5. Rate Controlling Factors
    6. pH Regulating Mechanisms
    7. An Example Simulation
    8. Discussion
    9. Extensions to the Ecosystem Model
    10. Conclusions
  7. Temperature and Moisture
    1. Natural Warming of Landfills
    2. 1-Dimensional Model
    3. Combined Model of Heat, Gas and Moisture Flow
    4. Enhancing Methane Production
  8. Additional Topics
    1. Introduction
    2. Settlement
    3. Methane Oxidation
    4. Moisture Flow in a Doubly-Porous Medium
  9. Overall Summary
    1. Gas Monitoring
    2. Network Pumping Installations
    3. Biological Processes
    4. Thermal Regulation
    5. Miscellaneous Topics
    6. Afterword
The full report also includes appendices describing: Finite Element Algorithm, 3-Dimensional ADI Methods, The Loscoe Explosion, Experimental Results from Sleap Landfill, Solution of Network Equations, Analytical Gas Flow Solutions, Biochemical Approximations, Thermal Parameters for Gas Evolution, Effects of Temperature, Effects of pH and Organic Acid Concentration, Analysis of Landfill Waste Used in Experiment, Solution of Gas Flow Equations.