喹啉降解菌的筛选及强化处理炼油废水的研究

STUDY ON THE ISOLATION OF BACTERIA FOR QUINOLINE DEGRADATION AND ENHANCED TREATMENT OF REFINING WASTEWATER

从某石化厂区内受污染土壤中分离出1株能利用喹啉作为唯一碳源、氮源和能源的肠杆菌属(Enterobacter sp.)菌株,该菌对喹啉表现出优异的降解特性,在纯培养条件下,30h内可将486mg/L的喹啉降解完全。该菌不仅可高效降解炼油废水中高浓度的喹啉,同时还能与其它微生物协同作用,降解炼油废水中的其它有机污染物,从而进一步降低出水中的CODCr浓度。高浓度喹啉对硝化菌只存在短暂的抑制作用,1周左右硝化活性即可恢复,喹啉的生物降解过程中释放出氨氮,增加氨氮负荷,但氨氮去除率只出现短暂的下降。在喹啉质量浓度为200～686mg/L的范围内,喹啉降解遵循零级反应动力学。

A bacterial strain capable of utilizing quinoline as sole source of carbon, nitrogen and energy was isolated from the petroleum contaminated soil of a petrochemical refinery. The isolate was identified as Enterobacter sp. having strong quinoline degradability. Biodegradation experiments showed that this strain could degrade 486 mg/L of quinoline in pure culture completely within 30 h. Said bacteria not only could degrade quinoline with high concentration in refinery wastewater efficiently, but also could co-treat other organic pollutants together with other organisms to further reduce the CODcr of effluent. The activity of nitrobacterium was inhibited by the high concentration of quinoline temporarily, yet it could he recovered in about one week. The biodegradation of quinoline released as ammonia into the growth medium, which increased the load of ammonia, however, the decrease of ammonia removal rate was also temporary. The degradation of quinoline followed zero-order kinetics equation when the concentration of quinoline in the range of 200 to 686 mg/L.