微宇宙系统中氯苯的生物强化处理

Treatment of chlorobenzene by bioaugmentation in a microcosm system

将分离出的一株降解氯苯的高效土著菌Acinetobacter calcoaceticus和自然材料组成微宇宙系统,通过改变系统组成、重金属和营养物添加水平、悬浮物浓度以及温度,研究了系统中氯苯的去除机制.结果表明,微宇宙系统中氯苯的去除主要是加入菌株的降解作用;加入降解菌后,8d内系统中氯苯的去除率可达到98.3%.底泥和光照对微宇宙系统中氯苯的去除具有明显的促进作用(p<0.05).悬浮物在实验前期对氯苯的去除产生明显的促进作用.微宇宙系统中氯苯的去除率随着温度的升高而增加,30.0℃条件下培养7d后,氯苯的去除率可达95.4%;10.0℃和15.0℃下培养14d后,氯苯的去除率分别为43.4%和68.5%.营养盐加入比例达1.0%时,可明显促进氯苯的去除.Cd2+和Hg2+浓度达到10.0mg·L-1时,可对系统中氯苯的去除率产生显著(p<0.05、p<0.01)降低作用.研究结果可为突发性事故造成的氯苯污染水体的微生物修复提供基本的理论和实践依据.

We investigated the removal mechanism of chlorobenzene in a microcosm system which was composed of natural material and the indigenous bacterial strain Acinetobacter calcoaceticus with strong ability to degrade chlorobenzene.The effects of the composition of the microcosm system,the presence of heavy metals and nutrients,the concentration of suspended matter,and temperature were studied.The results showed that the A.calcoaceticus strain played an important role in the removal of chlorobenzene and up to 98.3% of chlorobenzene was removed in 8 d in the microcosm system.Sludge and sunlight significantly increased the removal rate of chlorobenzene（p〈0.05）.At early stages,suspended matter obviously enhanced the removal of chlorobenzene.The removal rate of chlorobenzene increased with temperature.After incubation for 7 d at 30.0℃,95.4% of chlorobenzene was removed.But only 43.4% and 68.5% of chlorobenzene was removed after incubation for 14 d at 10.0℃ and 15.0℃,respectively.The addition of nutrients at a volume ratio of 1.0% significantly increased the removal rate of chlorobenzene.Cd2＋ and Hg2＋ at concentrations of 10.0 mg·L ^-1 significantly decreased the removal rate of chlorobenzene（p〈0.05 and p〈0.01）.Results of the study may supply basic theoretical and practical support for the bioremediation of water bodies accidentally polluted with chlorobenzene.