Removal of acrylonitrile vapor from waste gases by a trickle-bed air biofilter

The system performance of a trickle-bed air biofilter (TBAB) for treating acrylonitrile (AN) vapor from waste gases was investigated under different gas flow rates and influent AN concentrations. In steady-state conditions, the AN elimination capacity increased but the AN removal efficiency decreased with the increase of influent AN load. More than 95% AN removals were achieved for AN loads below 490 g AN m−3 h−1. The TBAB appeared to be a very effective treatment process for removing AN vapor at low to high loads, and the effectiveness could be maintained over a long period. Most AN vapors were removed in the earlier stages, indicating that a three-stage TBAB might be sufficient in the practical application.