Biofiltration of high loads of ethyl acetate in the presence of toluene

To date, biofilters have been used primarily to control dilute, usually odorous, off-gases with relatively low vola-tile organic compound (VOC) concentrations (<1 g m-3) and VOC loads (<50 g m-3 hr-1). Recently, however, U.S. industry has shown an interest in applying biofilters to higher concentrations of VOCs and hazardous air pol-lutants (HAPs). In this study, the behavior of biofilters under high loads of binary VOC mixtures was studied. Two bench-scale biofilters were operated using a commercially avail-able medium and a mixture of wood chips and compost. Both were exposed to varying mixtures of ethyl acetate and toluene. Concentration profiles and the correspond-ing removal efficiencies as a function of VOC loadin