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辽河油田欢５０ 块为低渗透油藏，孔隙度小，岩性致密，地层温度高，原油含蜡量高，凝固点高，导致生产时产量下降快，产能低，采出程度低。针对生产中的问题，进行了碱／ 表面活性剂复合驱提高原油采收率的研究。通过研究复合体系溶液与欢５０ 块原油的界面张力、复合体系溶液的长期热稳定性，从７ 种表面活性剂中筛选出既能降低油水界面张力，又能适应该油藏９９℃高温的表面活性剂，并研究了该表面活性剂和碱形成的复合体系在欢５０ 块油砂上的吸附以及复合体系溶液驱油效率。该体系在９９ ℃时能大幅度降低欢５０块原油的油水界面张力（达０．０１ ｍＮ／ｍ 以下） ， 并具有很高的驱替效率，水驱后注入复合体系段塞，平均采收率达６５．２４ ％ ，相对于水驱，提高采收率平均为１８．４％ 。并运用核磁共振成像技术研究复合体系溶液的驱油机理，复合体系注入前后核磁共振成像结果表明，复合驱能提高驱替效率，在复合体系前缘形成富集油带，对进一步采出水驱剩余油明显有效。
Liaohe Oilfield Huan 50 low permeability reservoirs, porosity, tight lithology, high formation temperatures, high crude oil wax content, high freezing point, resulting in production decreased rapidly, low productivity, low production level. Aiming at the problems in the production, the research on improving the recovery rate of crude oil by alkali / surfactant compound flooding was carried out. By studying the interfacial tension between the composite system solution and 50 crude oil and the long-term thermal stability of the composite solution, seven kinds of surfactants were selected to reduce the interfacial tension between oil and water and to adapt to the high surface temperature of 99 ℃ of the reservoir And studied the adsorption of the composite system formed by the surfactant and the base on 50 oil sands and the solution displacement efficiency of the composite system. The system can significantly reduce the oil-water interfacial tension (up to 0.01 mN / m) of 50 crude oil at 99 ° C and has a high displacement efficiency. After being flooded, the composite system slug is injected and the average recovery The rate of 65.24%, compared with water flooding, enhanced recovery of 18.4% on average. Nuclear magnetic resonance imaging was used to study the oil displacement mechanism of the composite system solution. The results of NMR imaging before and after the composite system injection show that the composite flooding can improve the displacement efficiency, enrich the oil belt on the front of the composite system, Oil is effective.