Can H2S affect the methane oxidation in a landfill?

The effects of H2S on CH4 biological oxidation in landfill cover soil (LCS) and aged municipal solid waste (AMSW) at different CH4 concentrations were investigated. The CH4 biological oxidation rates of LCS and AMSW were found to be significantly affected by CH4 concentration, with maximum oxidized concentrations of 5% and 20% of CH4, respectively, occurring within 20 d. These differences may have been due to different dominant methanotroph populations. The CH4 oxidation of LCS and AMSW was significantly inhibited by H2S at low CH4 concentrations (5%), but not at high levels of CH4 (20% and 50%). One possible pathway of the effects of H2S on CH4 oxidation was competitive inhibition. These findings indicate that AMSW, which could adapt to the complex LFG environment more easily in comparison to LCS, was more suitable for use as a landfill cover for CH4 emission mitigation.