High loading toluene treatment in a compost based biofilter using up-flow and down-flow swing operation.
A compost/ceramic (1:1, v/v) three section laboratory-scale biofilter inoculated with acclimated activated sludge was examined to treat high loading toluene vapors from a synthetic gas stream. The biofilter was operated continuously at different gas flow rates, 0.108-0.15m(3)h(-1), with inlet toluene concentrations ranging 0.5-13gm(-3). The overall performance of the biofilter was divided to seven stages according to the mode of operation (down-flow and up-flow) over a period of 102 days. Removal efficiencies ranging from 48 to 100% and elimination capacities ranging from 26 to 180gm(-3)h(-1) were observed depending on the initial loading rates and the mode of operations. A maximum elimination capacity of 180gm(-3)h(-1) was observed in the last period at an inlet toluene concentration of about 13gm(-3). The results showed that changing the mode of operation (up-flow and down-flow) periodically will improve the performance of the biofilter under high inlet toluene concentration (higher than 4gm(-3)). Results obtained in this study provide insight into the possibility of the biofilter to treat high inlet concentrations rather than low concentrations well known in the literature.
Znad
Hussein T
HT
Research Center for Biochemical and Environmental Engineering, Toyo University, Department of Applied Chemistry, Kawagoe, Saitama 350-8585, Japan. hznad@cc.mail.toyo.eng.jp
Katoh
Kyohei
K
Kawase
Yoshinori
Y
D000393:Air Pollutants / Q000032:analysis / Q000378:metabolism*; D000397:Air Pollution / Q000517:prevention & control*; D002245:Carbon Dioxide / Q000032:analysis / Q000378:metabolism; D002516:Ceramics; D005374:Filtration; D012722:Sewage / Q000382:microbiology; D012987:Soil; D014050:Toluene / Q000032:analysis / Q000378:metabolism*
D000393:Air Pollutants; D012722:Sewage; D012987:Soil; D002245:Carbon Dioxide; D014050:Toluene