Determination of the Hydrolysis Constant in the Biochemical Methane Potential Test of Municipal Solid Waste

This article provides the methane yield of municipal solid waste (MSW) and its main constituents using the biochemical methane potential (BMP) test. Methane yield of kitchen waste (KW), paper waste (PW), and garden waste (GW) were 357 (±24.7), 147 (±17.1), and 114 (±0.6) mL CH4/g VS, respectively. The hydrolysis constant in the first order kinetic model was 0.25, 0.095, and 0.121 d−1 for KW, PW, and GW, respectively. Effect of the inoculum to substrate (I/S) ratio in the BMP test of MSW was investigated. Methane yields of 297.4 (±18.6), 293.5 (±33.9), and 378.2 (±10.3) mL CH4/g VS were found at I/S ratios of 1.4, 7.2, and 12.9, respectively, whereas the hydrolysis constants were 0.112, 0.151, and 0.221 d−1. A new method based on the production of soluble chemical oxygen demand (SCOD) while selectively inhibiting methanogenesis has been used to determine the hydrolysis constant (0.25 d−1) according to its true definition, which is the conversion of particulate COD to SCOD, showing that the method ...