Abiotic and Biotic Compression of Municipal Solid Waste

作者：Bareither Christopher A^*; Benson Craig H; Edil Tuncer B; Barlaz Morton A

来源：Journal of Geotechnical and Geoenvironmental Engineering, 2012, 138(8): 877-888.

DOI：10.1061/(ASCE)GT.1943-5606.0000660

• Municipal solid waste
• Settlement
• Bioreactor landfills
• Methane generation
• Leachate
• Recirculation
• Biocompression

This study focused on quantifying relative contributions of abiotic and biotic compression of municipal solid waste (MSW). Abiotic mechanisms include immediate compression, mechanical creep, and moisture-induced waste softening. The biotic mechanism is decomposition of the MSW organic fraction, which when coupled with mechanical creep, yields biocompression. Three 610-mm-diameter laboratory compression experiments were conducted for 1,150 days under the following conditions: (1) waste with no liquid addition (dry), (2) liquid addition spiked with biocide (abiotic), and (3) leachate recirculation (biotic). Immediate compression strain was similar in all three tests (24-27%). Mechanical creep, moisture-induced softening, and biocompression were compared via time-dependent compression ratios (C-alpha%26apos;). Moisture-induced softening occurred in both the abiotic and biotic cells in response to liquid addition and leachate recirculation. Moisture-induced softening accelerated the accumulation of mechanical creep (i.e., approximately doubled C-alpha%26apos; due to mechanical creep relative to the dry cell), but did not increase the overall magnitude. C-alpha%26apos;, in the biotic cell, correlated with the methane flow rate when methanogenesis was controlled by the rate of solids hydrolysis. C-alpha%26apos;, due to mechanical creep in the dry cell and biocompression in the biotic cell, increased exponentially with temperature, and can be represented with an exponential model. C-alpha%26apos;, due to biocompression, was approximately one order of magnitude larger than C-alpha%26apos; due to mechanical creep. DOI: 10.1061/(ASCE)GT.1943-5606.0000660.

• 出版日期2012-8