低渗透油藏微生物采油现场试验研究

Microbial enhanced oil recovery in low-permeability reservoir

大庆油田朝阳沟低渗透油藏是高黏度、高含蜡油藏,应用一系列生化分析的方法和手段,评价、监测在该油藏进行的微生物采油矿场试验的效果。试验结果,使用的5种微生物在油层条件下都能较好存活,原油黏度的降低比率为43.7％,含蜡量平均下降32.6％,含胶量平均下降31％,微生物产生的脂肪酸等活性物质降低了油水间的界面张力;气相色谱分析发现,原油中的正构烷烃碳数分布曲线向轻组分方向移动。矿场试验所取得的增油效果证实,利用微生物能提高低渗透油藏的原油采收率,增加原油产量,降低含水率,可能成为较好的增产调整措施之一。

A huff-puff test with MEOR has been carried out in Chaoyanggou reservoir with a low permeability in Daqing Oilfield. By using a series of bio-chemical analyses, the evaluate and test on the effects of experiment and field show that the microbes can grow under the reservoir condition with low-permeability perfectly. The rheology of treated oil can be changed in a great deal and the content of paraffin and gel be reduced 31% and 32. 6%.respectively, due to the action of the bacteria. The interfacial tension between water and oil can be decreased. The gas chromatography analysis found that the light component increased and the heavy component decreased in crude oil. MEOR may be a good method to increase oil recovery and adjust wells for low-permeability layer with high viscous thinning oil.