Coupling ozone and hollow fibers membrane bioreactor for enhanced treatment of gaseous xylene mixture.

Two hollow fiber membrane bioreactors (HFMBRs) inoculated with activated sludge were used in series to biodegrade continuously mixed xylene. The influence of gas residence time (τ) and mass loading rate (LR) on elimination capacity (EC) of the mixed xylene was investigated. A maximum elimination capacity (EC(max,v)) of 466gm(-3)h(-1) was achieved at τ=10s and LR(v)=728gm(-3)h(-1). Thereafter, ozone was introduced into inlet gas and the influence of ozone was investigated. Results showed that the maximum xylene elimination capacity increased from 524gm(-3)h(-1) to 568gm(-3)h(-1) and 616gm(-3)h(-1) at τ=10s, respectively when the inlet ozone concentration rose from 200mgm(-3) to 400mgm(-3) and 600mgm(-3), respectively. HFMBR coupled with O(3) has higher performance and stability for the long-term operation at the same condition.