Performance of Trickle Bed Biofilters under High Toluene Loading

摘要

The performance of two pelletized media biofilters, highly loaded with toluene,was evaluated in this study. Both biofilters were operated at the same influent concentration of 250 ppmv toluene. Biofilter 'A' was operated at 1 minute EBRT and biofilter 'B' at 0.67 minute EBRT. The impact of backwash duration on performance was studied for both biofilters, primarily the stability of performance between backwashings. This biofilter behavior indicated that increasing the backwash period from 1 to 2 hours was effective in improving the performance stability of both biofilters. This improved performance stability is due to reduction of short circuiting within the media, caused by accumulating biomass.