GAS SIMULATION-MODELS FOR SOLID-WASTE LANDFILLS

Sanitary landfills remain an attractive disposal route for municipal s olid waste, because, in most cases, it is more economical than other a lternatives such as incineration and composting. Although the composit ion of solid waste may very substantially with location and time, orga nic materials constitute the vast majority of this waste. Organic mate rials are susceptible to microbial decomposition that result in gas an d heat generation within the landfill. The migration of gas away from the landfill boundaries and their release into the surrounding environ ment, present serious environmental concerns at both existing and new facilities. Mathematical models have been used widely to evaluate gas and heat generation and transport processes in landfills. This article presents a critical review of models designed to simulate biological, chemical, and physical processes responsible for the generation and t ransport of gas and heat in landfills.