Effects of biodegradable substrates and microbial concentration on the acclimation of microbes to acrylonitrile in aerobic submerged biofilter

The effects of coexistence-of biodegradable substrates and microbial concentration on the acclimation of microbes to acrylonitrile (AN) in an aerobic submerged biofilter were investigated on the basis of kinetic and ecological studies. The experimental results show that the acclimation of microbial film to AN was promoted by a higher microbial concentration in the biofilter and by the coexistence of glucose and peptone in the influent. It was clarified that the upper limit of AN loading to the biofilter for the ultimate degradation, i.e., complete mineralization, of the influent AN was about 2.0-2.2 kg/m³. d. In addition, a new microbial quinone profile method was applied for the analysis of the microbial community change in the biofilter. The change in quinone profiles of the microbial film during the acclimation to AN suggested that Brevibacterium sp., Pseudomonas aeruginosa and Corynebacterium sp. could contribute to the degradation of AN in the aerobic biofilter.