大庆油田聚驱后油藏内源微生物激活剂的筛选和效果评价

Screening and Effect Evaluating the Activator for Indigenous Microbe of Daqing Flowing Gel Flood Reservoirs

聚合物驱油后的油藏含水大幅回升,操作成本高,传统化学方法很难继续提高采收率,而内源微生物采油技术是最有希望的接替技术之一.针对大庆油田聚驱后油藏,利用分子生态学技术考察目标油藏的菌群结构,并通过统计学方法对内源微生物激活剂进行筛选和效果评价.结果表明目标油藏具有多种采油功能微生物,确定以糖蜜,硝酸盐,磷酸盐及酵母粉为主的激活剂体系,该体系能显著提高内源微生物的数量,有益菌浓度提高1～3个数量级,代谢产生的表面活性剂能将原油完全乳化分散,形成稳定的悬浊液,同时也能兼顾厌氧微生物的生长及产甲烷菌代谢产甲烷,因此具备实施内源微生物采油的潜力.

The water content rise again in flowing gel flood reservoirs, and because of the high cost, it may not continue enhancing oil recovery by traditional chemical method. Microbe enhancing oil recovery （MEOR） technology is one of the potential competences. This study focused on screening and evaluating the activator of Daqing flowing gel flooding reservoirs. The results of flora analysis showed that there are a plenty of flooding-functional microbes in the targeted reservoir. The activator system, which contain molasses, nitrate, phosphate, yeast powder, can remarkably achieve indigenous microbe growth. The crude oil can be entirely emulsified by metabolic product of the indigenous microbe, which can also produce methane gas under anaerobic conditions. It seemed by all certifications that the activator had the potential application in MEOR.