一株产表面活性剂的菌株的筛选及现场试验研究

Screening of a strain producing surfactant

从胜利油田油水样中分离到一株高温条件下能够利用烃类产生表面活性剂的菌株A2,经鉴定属于Petrobacter.该菌株对两种原油的降解、降黏和降凝结果表明:对孤岛油的降解率较高,为39.81%,对甘17油的降解率达22.60%;对孤岛油的降黏率可达37.95%,对甘17油的降黏率为25.00%;A2可将孤岛油和甘17油的凝固点降低2.5℃.通过菌株作用岩石表面,表明该菌株对玻璃试片作用后其接触角降低最为明显,高达72%,接近于对照菌样的5倍;石英和灰岩的接触角也分别降低了68%和24%.表明A2具有一定的改变岩石表面性质的能力.增油效果评价实验结果表明:A2菌在中一驱Ng3油藏条件下,微生物驱提高采收率9.3%.现场实施后取得了降水增油效果,试验区含水下降2.1%,累积增油0.36×104t,提高采收率0.21%.

A strain A2 is separated from the oil /water sample in Shengli Oilfield,which can produce surfactant by means of hydrocarbons at high temperature.It belongs to Petrobacter.The experimental results show that,the degradation rate of the strain to Gudao crude oil and Gan 17 crude oil can reach to 39.81% and 22.60% separately;its viscosity reducing ratio to Gudao crude oil and Gan 17 crude oil can reach to 37.95% and 25.00% separately;it can make the solidifying point of Gudao crude oil and Gan 17 crude oil decrease 2.5 ℃.After the surface of glass,quartz and limestone is treated by the strain liquid,their contanct angle can decrease by 72%,68% and 24% separately.Under the condition of Ng3 oil reservoir,the microbial flooding of the strain can enhance the recovery factor by 9.3%.Field test shows that,in the microbial flooding test area,the water cut decreases by 2.1%,the cumulative oil yield increases by 0.36×104 t,and the recovery factor enhances by 0.21%.