Performance evaluation of a thermophilic biofilter for the removal of MTBE from waste air stream: Effects of inlet concentration and EBRT

The removal of MTBE from a waste air stream was investigated using a bench scale thermophilic biofilter. After developing a high population of acclimated organisms capable of degrading MTBE, the biofilter achieved complete removal of MTBE at an inlet concentration of 100 ppm during startup. The performance of the biofilter was then evaluated under different operational conditions, including MTBE concentrations ranging from 100 to 3000 ppm and empty bed retention times (EBRTs) between 15 and 60 s, corresponding to inlet mass loading of 20–650 g-MTBE m−3 h−1. All the experiments were conducted at a constant bed temperature of 52 ± 3 °C. The biofilter efficiently treated MTBE at loads up to 330 g-MTBE m−3 h−1 with very high removal efficiencies of greater than 99%. The elimination and mineralization capacities at critical loading rate were 326 and 165 g-MTBE m−3 h−1, respectively. The findings of this study indicate that thermophilic biofiltration can be a promising process for treatment of waste air streams containing toxic compounds.