14 Methane Production from Landfills
Downloaded by UNIV OF CALIFORNIA SANTA BARBARA on October 20, 2015 | http://pubs.acs.org Publication Date: January 29, 1981 | doi: 10.1021/bk-1981-0144.ch014
An Introduction EDWARD J. D A L E Y , IRA J. WRIGHT, and ROBERT E. SPITZKA Brown and Caldwell Consulting Engineers, Resource Recovery and Energy Conservation, 1501 North Broadway, Walnut Creek, C A 94596
The sanitary landfill process was developed to provide a means of disposal of wastes, particularly urban refuse and industrial solid wastes, in a manner that will not pollute the environment. In simple terms, this is accomplished by sealing the wastes to prevent interaction with the environment. Soil with low permeability provides the seal. The integrity of the seal is dependent upon the quality of the landfill operation, especially the cover soil compaction requirements. In a well-designed landfill, the movement of moisture and gas into or out of the interior of the landfill is significantly restricted to create a relatively closed environment for the wastes. Within this closed environment can be found an extremely wide variety of materials. Though waste composition differs widely from place-to-place and from season-to-season, a typical landfill can be expected to have a composition similar to that shown in Table I (1). The waste contains considerable moisture (about 25 percent by weight) and a high concentration of organics. As a result of the collection, unloading, spreading, and compaction of wastes during landfilling, the fill material will be heterogeneous with a large surface area-to-volume ratio. It will be under compression due to the weight of the compacted trash and earth above it. D u r i n g t h e l a n d f i l l i n g process, a c e r t a i n a m o u n t o f air w i l l be t r a p p e d in t h e landfill interior a l o n g w i t h t h e trash. T h e q u a n t i t y of air c a n n o t be d e t e r m i n e d , but c a n logically be e x p e c t e d t o be s i g n i f i c a n t . A small a m o u n t o f free w a t e r
0097-6156/81/0144-0279$05.00/0 © 1981 American Chemical Society
In Biomass as a Nonfossil Fuel Source; Klass, D.; ACS Symposium Series; American Chemical Society: Washington, DC, 1981.
Downloaded by UNIV OF CALIFORNIA SANTA BARBARA on October 20, 2015 | http://pubs.acs.org Publication Date: January 29, 1981 | doi: 10.1021/bk-1981-0144.ch014
BIOMASS AS A NONFOSSIL F U E L SOURCE
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