Evaluation of Different Packing Media Capacities Used in the Biofilters for Hydrogen Sulfide (H2S) Removing from Polluted Air

The hydrogen sulfide is a toxic, flammable and colorless gas. Traditionally, the control of H2S emissions includes direct air stripping, precipitation and chemical oxidation. Considering the advantages of biological methods, this study aimed at treating H2S using biofiltration. Three types of media; a pearl medium, a compost medium and an activated carbon medium, were evaluated for sulfur inhibition and capacity for removal of hydrogen sulfide (H2S). In this study, the biofilter columns were constructed using transparent plexyglass pipes with a diameter of 15 cm and a height of 40 cm, with a bed depth of 27.5 cm. Have been measured, produced H2S gas was passed through the three different biofilter media and effluent readings for H2S at the outlet points of three different columns were measured. The three biofilters with different media blends were operated in parallel for ten weeks continuously treating hydrogen sulfide, at various flow rates and concentrations. After being stabilized, the overall removal efficiencies of three different columns were measured at the outlet points and observed that the efficiency of the column packed with activated carbon remained ~100% at different flow rates, concentrations and empty bed retention times (EBRT). The overall removal efficiency of compost and seashell media columns was similar in about 88-90% and 80-90%, respectively. Biological treatment of air emissions is a cost-effective, environmentally friendly and sustainable control technology for industrial and municipal facilities. Having lesser pollution potential in end products as well as lower operational and maintenance costs are the other advantages of these systems.