2012 journal article

Abiotic and Biotic Compression of Municipal Solid Waste

JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING, 138(8), 877–888.

co-author countries: United States of America 🇺🇸
author keywords: Municipal solid waste; Settlement; Bioreactor landfills; Methane generation; Leachate; Recirculation; Biocompression
Source: Web Of Science
Added: August 6, 2018

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 (Cα′). 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 Cα′ due to mechanical creep relative to the dry cell), but did not increase the overall magnitude. Cα′, in the biotic cell, correlated with the methane flow rate when methanogenesis was controlled by the rate of solids hydrolysis. Cα′, 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. Cα′, due to biocompression, was approximately one order of magnitude larger than Cα′ due to mechanical creep.