Landfill Odor (Hydrogen Sulfide) Control Using Novel Biogeochemical Cover System

Odor is a grave concern at the municipal solid waste (MSW) landfills. Hydrogen sulfide (H2S) is one of the major odor causing components of landfill gas (LFG). Recently, a novel biogeochemical cover system has been proposed, which incorporates biochar amended soil to mitigate methane (CH4) through biologic oxidation and basic oxygen furnace (BOF) slag to mitigate carbon dioxide (CO2) and H2S through geochemical reactions. Series of batch and small-scale column experiments were performed with BOF slag to evaluate the potential of slag to remove H2S. In addition, large-scale column experiments were performed simulating biogeochemical cover profile consisting of BOF slag layer overlying biochar amended soil layer, exposed to continuous flow of synthetic LFG comprising 48.25% CH4, 50% CO2, and 1.75% H2S (v/v). The BOF slag showed significant H2S removal potential up to 30 g H2S/kg BOF slag through batch and small column experiments. During large-scale column experiments, all the H2S was removed in the biochar amended soil layer indicating significant H2S removal potential in biochar amended soil. Since BOF slag also possesses significant H2S removal potential, potential of biochar amended soil to remove H2S adds to the overall H2S removal potential of the novel biogeochemical cover system.