Compression Behavior of Municipal Solid Waste: Immediate Compression

Abstract

An evaluation of scale effects, stress, waste segregation, and waste decomposition on the immediate compression behavior of municipal solid waste is presented. Laboratory experiments were conducted in 64-, 100-, and 305-mm-diameter compression cells. A field-scale experiment [Deer Track Bioreactor Experiment (DTBE)] was conducted on waste of the same composition and material properties. A methodology is presented for determining the end-of-immediate compression strain (ɛEOI) that is applicable to both laboratory- and field-scale data. The compression ratio (Cc′) was comparable between tests conducted in 100- and 305-mm compression cells. Compression tests in 305-mm cells conducted on six wastes (three size-differentiated fresh wastes and three decomposed wastes) yielded Cc′ ranging from 0.22 to 0.28 in the stress range of 25–100 kPa. A similar Cc′ (0.23) was determined for the DTBE (20–67 kPa). The variation in Cc′ is related to the waste compressibility index (WCI), which is a function of waste dry weight water content, dry unit weight, and the percent contribution of biodegradable organic waste (paper/cardboard, food waste, yard waste). A compilation of laboratory data from this study and the literature yielded a predictive relationship for the Cc′ and WCI. The Cc′ can be estimated within ±0.087 for a given WCI using this relationship.