几株机油降解菌及其处理含油废水的效果

Three Lubricating Oil Degrading Bacterial Strains and Their Use for Treating Oily Wastewater

以20号机油为唯一碳源,用无机培养基在30℃摇床培养7 d,从中原油田采油污水和咸阳炼油厂活性污泥中分离出10株烃降解菌。在进一步摇床培养中,从10株菌中得到了对20号机油降解能力最强的3个菌株Ⅰ12、Ⅰ13及Ⅱ3,其除油率分别为37.2%、38.8%及47.5%,在重复3次的摇瓶培养中,除油率分别为34.5%、36.7%及23.4%。在培养时间筛选实验中,求得Ⅰ13菌株在30℃摇床培养3 d时,除油率达到最大,培养液pH降至最小。将Ⅰ12、Ⅰ13及Ⅱ3 3株菌株用于某石化厂含油污水(含油量661.7 mg/L,CODcr值1977.3 mg/L)处理,30℃摇瓶培养3 d,重复3次,求得除油率分别为45.4%、44.1%及36.7%,CODcr去除率分别为18.4%、55.7%及32.0%。图1表3参6。

10 bacterial strains capable of degrading hydrocarbons are isolated and cultivated from oilfield produced water of Zhongyuan and activated sludge of Xianyang refinery with inorganic nutrients and 20 # lubricating oil （20 # LO） as the onty carbon source on shaking table at 30℃ in 7 days. By further shaking table cultivation 3 strains with significant degrading capability for 20 # LO are chosen from 10 and these are Ⅰ 12, Ⅰ13, and Ⅱ3, givingan oil removal rate （ORR） of 37.2%, 38.8%, and 47.5%, respectively, and in 3 times repeated shaking bottle tests these strains give ORR of 34.5% ,36.7%, and 23.4%, respectively. In shaking table test for strain Ⅱ13 at 30℃, the ORR reaches the highest value and the pH of the culture--the lowest value in 3 days. When using these strains, Ⅰ12, Ⅰ13, and Ⅱ 3, for treating diluted oily wastewater from a petrochemical plant with oil content 661.7 mg/ L and CODcr 1977.3 mg/L by the way of shaking bottle cultivation at 30℃ in 3 days, an ORR value of 45.4% ,44.1%, and 36. 7% and a CODcr value of 18.4%, 55.7%, and 32.0%, respectively, are obtained.