Modeling the biofiltration of air emissions containing reduced sulfur compounds and volatile organic compounds

The objectives of this study were to identify and model the interaction effects between reduced sulfur compounds and volatile organic compounds in biofiltration. Three laboratory-scale biofilters packed with Nova Inert ® were used to study biofiltration of hydrogen sulfide and methanol at 30°C and pH 7. The target concentration ranges for hydrogen sulfide and methanol were 0–250 ppmv and 0–400 ppmv respectively. Hydrogen sulfide removal rates up to 144 g H₂S/m3bed/h were observed during early experiments; however, the predicted long-term maximum removal rate is 56–66 g H2S/m3bed/h. Methanol removal rates up to 380 g methanol/m3bed/h were achieved, and no decline in performance over time was observed. No interaction effects between hydrogen sulfide and methanol were observed. Hydrogen sulfide removal followed Monod kinetics, while methanol removal was first order. Reaction-limited and biofilm based models were used to model the removal of both substrates in biofilters.