空气辅助微生物改变地层岩石与流体性质的能力研究

为了提高微生物采油的应用效果,研究了空气辅助对微生物改变地层岩石与流体性质作用机理。通过实验研究空气辅助微生物改变岩石表面润湿性、油水界面张力及微生物降解原油机理,以岩石润湿性和油水界面张力改变为基础,探讨了空气中氧对微生物改变岩石表面和黏附功的影响。实验结果表明,空气中氧可提高微生物菌液改变石英表面润湿角速度,溶氧4.5～5.5mg/L菌液中润湿角降低50.14%～56.94%。4.5 mg/L溶氧条件下,菌液作用后原油界面张力下降80%。与含溶氧5.5mg/L培养的微生物作用后,油质组分增加8.414%,蜡质组分降低7.728%,胶质组分降低5.538%。实验表明,空气辅助可增强微生物改变地层岩石与流体性质的能力,进一步提高原油采收率。

Research on the influence of air assisted microbial action on the properties of porous rock and formation fluid

For the purpose of improving the application effect of MEOR, the influence of air assisted microbial action on the properties of porous rock and formation fluid was studied. The wettability, oil-water interfacial tension and oil degradation by microorganism were measured through experiment. Based on the changes of rock wettability and oil-water interfacial tension, the influence of the oxygen in the air on the microbial action to the rock surface and work of adhesion was discussed. The experiments results showed that oxygen can improve the rate of microbial changing wetting angle of quartz surface. The wetting angle reduced by about 50.14%-56.94% at dissolved oxygen concentration of 4.5-5.5 mg/L. The oil-water interfacial tension reduced about 80% at dissolved oxygen concentration of 4.5 mg/L. In addition, at dissolved oxygen concentration of 5.5 mg/L, the light components of oil increased about 8.414%, the wax components reduced 7.728%, and gelatine components reduced 5.538%. These experiments revealed that air assist could enhance the ability of microbial changing the properties of porous rock and formation fluid to further improve oil recovery.