Evaluation of Greenhouse Gas Emission from Municipal Solid Waste Leachate by two-stage Sequencing Batch Reactor

Abstract

This work investigated greenhouse gas emission during the treatment of municipal solid waste leachate by two-stage Sequencing Batch Reactor (SBR). The SBR was carried out by anaerobic reactor followed by aerobic reactor. The system was operated at hydraulic retention times (HRT) of 4 and 2 days during 130 operating days. At steady state, the organic removal efficiencies were found to be 67.0% and 62.7% for 4 and 2 days of HRT. The organic carbon and nitrogen were mainly removed in aerobic reactor. The surface emission rates of methane in anaerobic reactor were 0.181 and 0.292 g/m2.d under HRT of 4 and 2 days, respectively. The emission factors of CH4 at HRT 4 and 2 days were 0.297 and 0.238 gCH4/gCOD, respectively while those of N2O were 0.25 and 0.19 gN2O/gN for HRT of 4 and 2 days, respectively. The PCR technique confirmed that the microbial group was methonogenic bacteria which corresponded to the emission of greenhouse gas. Type of Paper: Empirical Keywords: Greenhouse gas; leachate; methane emission; microbial communities; sequencing batch reactor