|
This paper investigated the removal of carbamazepine and nitrobenzene in an enhanced membrane bioreactor by adding powder activated carbon (PAC). The experimental results of two and half months' continuous operation showed that nitrobenzene can be removed completely no matter whether PAC was added or not. And the contributions of natural volatilization, aeration and activated sludge for the removal of nitrobenzene are 15.2%, 22.2%, and 62.6%, respectively. In comparison to nitrobenzene, carbamazepine's removal was of no avail after one month's operation without adding PAC, however, the removal efficiency of carbamazepine in the enhanced membrane bioreactor with PAC maintained at a stable level of 30%~40% after one month's operation. After PAC dosing, the amounts removed by adsorption and missing (probably biodegradation) both increased greatly, and the overall removal efficiency of carbamazepine raised 24.44 percents. These results indicate the possibility that PAC cannot only adsorb carbamazepine but also promote the biodegradation of carbamazepine. Furthermore, the sludge-water partition coefficient (Kp) and total adsorbed amounts of carbamazepine before and after PAC dosing are ascertained and compared. |
|
Keywords:Adsorption; carbamazepine; membrane bioreactor; nitrobenzene; PAC; pharmaceuticals |
|