Removal of benzene and toluene in polyurethane biofilter immobilized with Rhodococcus sp. EH831 under transient loading.
The performance of a polyurethane (PU) biofilter inoculated with Rhodococcus sp. EH831 was evaluated under different transient loading conditions, such as shutdown, intermittent and fluctuating loading. A mixture of benzene and toluene vapors was employed as model pollutants. When the biofilter was restarted after a 2 week-shutdown, during which neither clean air nor water was supplied, the benzene and toluene removal capacities were rapidly restored after a re-adaptation period of only 1 day. A comparison of the removal capacity under continuous and intermittent loading revealed that constant and periodic loading (8 h on/16 h off per day) and a 2 day-shutdown did not significantly influence the biofilter performance, although the removals of benzene and toluene were relatively unstable and lower under intermittent loading during the initial week. The result of quantitative real-time PCR showed that Rhodococcus sp. EH831 could be maintained during transient loading periods (10(10)-10(11) CFU/g-dry PU) irrespective of the different operating conditions.
Lee
Eun-Hee
EH
Department of Environmental Science and Engineering, Ewha Womans University, Seoul 120-750, Republic of Korea.
Ryu
Hee Wook
HW
Cho
Kyung-Suk
KS
D000388:Air; D000393:Air Pollutants / Q000302:isolation & purification; D001554:Benzene / Q000737:chemistry / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D001709:Biotechnology / Q000379:methods; D004784:Environmental Monitoring / Q000379:methods; D005374:Filtration; D005740:Gases; D011140:Polyurethanes / Q000737:chemistry* / Q000302:isolation & purification*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012240:Rhodococcus / Q000378:metabolism*; D013997:Time Factors; D014050:Toluene / Q000737:chemistry / Q000302:isolation & purification*
D000393:Air Pollutants; D005740:Gases; D011140:Polyurethanes; D014050:Toluene; D001554:Benzene