Q-315. Effects of Transient loading on the Removability of Benzene and Toluene in a Polyurethane Biofilter

E-H. Lee, K-S. Cho;
Ewha Womans Univ., Seoul, REPUBLIC OF KOREA.

The effects of transient loading such as shutdown, shock loading, and periodic loading on biofilter performance were investigated. The relationship between the contaminants (benzene and toluene gases) removal efficiency and microbial activity at transient loading conditions were also clarified using real-time PCR. Rhodococcus sp. EH831 was inoculated in the polyurethane biofilter, and the mixed gases of benzene and toluene were supplied into the biofilter at various transient loading containing periodic feed on/off (feed on for 8 h/feed off for 14 h), short term shutdown (feed on for 5 d and feed off for 2 d), long term shutdown (14 d), shock loading, and periodic shock loading feed on/off conditions. Compared with the biofilter performance at continuous and constant loading condition (control), there was no significant decrease of removability at all transient loading conditions, even though the biofilter performance was more stable and higher removability at control condition until 2 w. Based on the quantitative analysis of Rhodococcus sp. EH831 using real-time PCR, the viable cell numbers of Rhodococcus sp. EH831 were ranged from 109 to 1010 CFU/g-dry packing medium, indicating that the microbial activity in the biofilter wasn’t inhibited at transient loading conditions. These results suggest that polyurethane biofilter inoculated with Rhodococcus sp. EH831 can show stable and excellent performance at transient loading conditions.