chapter 4: temperature inside the landfill

CHAPTER 4: TEMPERATURE INSIDE THE LANDFILL:
EFFECTS OF LIQUID INJECTION AND AMBIENT
TEMPERATURE
publication.
NOTE: This chapter will be submitted to Waste Management and Research for
4.1 Introduction
In 2006, in the United States, 32 percent of solid waste was recovered and recycled or
composted, 14 percent was burned at combustion facilities, and the remaining 54 percent was
disposed of in landfills (EPA, 2006), indicating the importance of landfills in MSW management
strategies in the USA. The traditional approach to landfill operation involves minimizing entry of
moisture into the landfill. This approach reduces the leachate production but slows the
degradation of MSW.
A better approach for MSW management is the bioreactor landfill in which leachate
produced is recirculated back into the landfill. In the case that leachate is not generated in
sufficient quantity, addition of other liquid such as groundwater may be necessary. Liquid
injection enhances moisture content, environmental conditions (temperature and pH) conducive
for degradation, settlement, methane production and biological decomposition of the waste
inside the landfill (Eliassen, 1942; Rees, 1980; Buivid et al, 1981; Townsend et al, 1996;
Wreford et al, 2000, San and Onay, 2001).
As liquid is being injected into the landfill, one of the major concerns is the efficacy of
the injecting system. It would be beneficial for the landfill manager to know the best way to
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