Hydrogen sulfide removal by compost biofiltration: Effect of mixing the filter media on operational factors

The overall goal of this work was to determine the effect of mixing the filter media of a compost biofilter on H2S removal efficiency. The behavior of important operational factors such as moisture of filter media, pressure drop and sulfate accumulation were evaluated, considering mixing the media. Additionally, tracer studies were performed in order to determine the effect of mixing the media on gas distribution. H2S removal capacity decreased over time, from 100% to 90%. When bed mixing was carried out, the removal capacity remained constant, close to 100%, and moisture content and sulfates accumulation were better controlled at 50% and at 12 mg S-SO4/g dry media respectively. In addition, under this operational pattern, an improvement in gas and particle size distribution was observed inside the filter media, fitting the axial dispersion model and the Ergun equation.