Performance evaluation and microbial community analysis of the biofilter for removing grease and volatile organic compounds in the kitchen exhaust fume

[Display omitted] •The biofilter packed with corncob activated carbon was constructed.•More than 90% RE of grease and TVOCs were observed in 45-day period.•The pH and moisture content of the filler had a certain influence on RE.•The ECmax of grease and TVOCs were 112 and 235 g/(m3·h), respectively.•Thermobacillus sp. was found the dominating group in the packing media. Corncob-based activated carbon has very good adsorption performance and can provide a favourable growing environment for microorganisms. In this study, a biofilter packed with corncob-based activated carbon was constructed to remove grease and total volatile organic compounds (TVOCs) in kitchen exhaust fume. Results show that the biofilter was suitable for the biodegradation of grease and VOCs, and the maximum elimination capacities (ECmax) were 112 and 235 g/(m3·h) at an empty bed residence time of 3.24 s, respectively. When the pH of the filler dropped to 5.0 ± 0.2, the removal efficiencies (RE) of grease and TVOCs in the biofilter decreased to the minimum values (75% and 77%, respectively). The REmax were respectively 88 ± 4% (for TVOC) at 70% filler moisture content and 90 ± 3% (for grease) at 76% filler moisture content. Molecular characterization results showed Thermobacillus sp. as dominating microbial group in the packing media.