内源微生物长岩心激活实验研究

用800 cm长岩心驱替系统,对新疆油田某区块内源微生物驱油进行了室内物理模拟研究,跟踪检测了模拟过程中微生物、营养物及代谢产物的变化。实验结果表明,长岩心不同位置的激活效果不同,大致分为富氧段、缺氧段和厌氧段三段。岩心不同位置的好氧菌菌数不同,富氧段菌数明显高于厌氧段。各取样点表面张力的变化没有规律,有升有降,表面张力从初始的57.7 mN/m降至最低值41.51 mN/m。驱出液中微生物、营养物和代谢产物的运移规律相似,随驱出体积的增加,菌数、总碳和总氮含量先增加后降低。激活后有益菌数量大幅增加,硫酸盐还原菌数量得到有效抑制,最终提高采收率幅度达5.84%。内源微生物在油层条件下被有效激活,初步验证了内源微生物两步激活理论,表明内源微生物驱油具有良好的驱油效果和发展前景。图5表1参12

Laboratory Study of Indigenous Microorganism Activation System in Long Core

A long core physical simulation system(800 cm) was applied to study the indigenous microorganism flooding on a block of Xinjiang Oilfield.Tracking measurement was investigated on the variation of microorganism,nutrition and metabolite.The activation result was different at different position which could be approximately divided into three parts,such as oxygen-enriched part,oxygen-lacked part and anaerobic part.The results showed that the cell population of aerobic bacteria was different at different position in the porous medium and that of the aerobic position was obviously higher than that of anaerobic position.There was no regularity about the surface tension at different sample points,and the measured value had ups and downs.The surface tension of culture medium reduced from 57.7 mN/m to the lowest value 41.51 mN/m.The cell population,total content of organic carbon and total content of nitrogen increased first and then decreased with increasing output of produced fluids.The cell population of probiotics had a large scale enhancement,and that of the sulfate-reducing bacteria was inhibited efficiently.The ultimate recovery increased by 5.84% OOIP.The indigenous microorganism was activated efficiently in simulated oil-bearing formation,and the results reflected the succession from aerobic to anaerobic microorganism in reservoir,which indicated that the flooding effect and development prospect of enhanced oil recovery employing indigenous microorganism was good.