高温产乳化剂菌原位生长下的微观驱油机理

Microscopic oil displacement mechanism of thermophilic bioemulsifier-producing bacteria in-situ growing

以高温产乳化剂菌嗜热脂肪地芽孢杆菌SL-1为对象,研究该菌株的生长和界面趋向性,同时利用微观仿真可视模型,研究SL-1菌对水驱后残余油的驱替作用和机理。结果表明:该菌具有嗜烃性能,在高温(65℃)和高压(10MPa)复合极端环境中,SL-1菌能够以原油为唯一碳源进行繁殖代谢,降解原油;代谢产生的生物表面活性剂具有乳化原油和改变岩石润湿性的作用,残余油被乳化分散成油滴;此外,该菌可降低油水界面张力和原油粘度,改善残余油的流变性。膜状残余油、柱状残余油以及盲端残余油等不同类型的残余油都能被有效驱替,最终提高原油采收率为12.84%。

The thermophilic bioemulsifier-producing bacteria,Geobacillus stearothermophilus SL-1,was chosen as target species to study growth characteristics and tendency on interface.Simultaneously,the experiment of the displacement effect and mechanism of residual oil after water flooding with strain SL-1 were carried out by microscopic simulation visual mod-el.The results reveal that Geobacillus stearothermophilus SL-1 has hydrocarbon degradation activity using crude oil as sole carbon source.Under compound extreme environment of high temperature(65℃)and high pressure(10 MPa),SL-1 bacte-ria can multiply and metabolize with crude oil so as to degrade oil;biosurfactants produced from the bacteria can emulsify crude oil,change rock surface wettability and disperse residual oil emulsion to oil drops;the oil-water interfacial tension and viscosity of crude oil can be reduced effectively,and the rheology of residual oil may be improved.All kinds of residual oil such as membrane residual oil,columnar residual oil and blind end residual oil have been displaced effectively.At last the oil recovery rate was increased by 12.84%.