Landfill gas extraction and purification technologies

Abstract

The extraction and purification technologies of landfill gas (LFG) from municipal waste continue to generate strong environmental concerns. Historically, the focus of these concerns was an odour in the immediate region of the landfill and the risk of explosions in structures caused by the movement of LFG through soil. While these are still important environmental issues, health risks associated with volatile organic compounds in LFG and damage to the atmosphere through the emission of greenhouse and ozone depleting gases, have also become prominent issues. The primary objective of this project is to study and examine LFG generation, extraction and purification technologies. Composition of LFG and gas extraction processes is analyzed. Comprehensive literature review of different models for LFG generation rate is provided. The study of LFG extraction and collection systems including design considerations and gas capture schemes are examined. Complete analysis of current purification processes of LFG along with upgrading techniques of methane to bio-methane are carried out. Discussion and recommendation on gas purification methods are conducted relevantly with certain type of LFG composition, level treatment required, quality of LFG anticipated, and its final application. Accurate portrayals of prior and current LFG extraction and purification technologies will advance the knowledge used to select appropriate waste management and reduction strategies in future.