Hydrogen Sulfide Removal from Biogas Using Pure and Mixed Cultures of Sulfide-Oxidizing Bacteria Biofiltration

Abstract

A novel biofiltration system using pure and mixed cultures of sulfide-oxidizing bacteria immobilized on granular activated carbon (GAC) to purify synthetic and real biogas from a sulfate reaction reactor of concentrated latex industry, contaminated by H2S, was studied. Complete H2S removal from synthetic biogas was found in pure and mixed culture reactors at 200 ppm initial H2S concentration, 35 l h−1 of biogas flow rate and 5.83 l h−1 of airflow rate. H2S removal using biofiltration had little effect on the methane content of synthetic biogas. Pure and mixed culture reactors at airflow rates of 0.75–5.83 l h−1 also showed complete H2S removal from real biogas. However, H2S removal efficiency at the airflow rate of 0.53 l h−1 decreased to 99%. Thus, H2S removal using biofiltration had little effect on the methane content of real biogas. The results of this study suggest the feasibility of developing using mixed culture of sulfide-oxidizing bacteria from concentrated latex wastewater for industrial application to remove H2S from biogas through biofiltration.