组合驱提高原油采收率实验研究

根据河南油田双河北Ⅱ4-5块已完成聚合物和微凝胶驱的现状，提出了对聚合物驱、聚合物／表面活性剂二元复合驱、微凝胶驱优化组合进行组合驱提高其原油采收率的观点。并在数模优化组合驱段塞构成的基础上，对不同渗透率的天然岩心与人造岩心进行了驱油实验。实验表明在双河北Ⅱ4-5块聚合物驱后实施组合驱提高原油采收率不仅可行，而且采收率（天然岩心）达13％。在最佳注入速度（14．2m／d）下，采收率高达15．7％。其驱油机理是调堵提高波及系数和降低油水界面张力而提高洗油效率。

EXPERIMENTAL STUDY ON COMBINATION FLOODING ENHANCING OIL RECOVERY

According to the situation that polymer flooding and micro-gel flooding have been completed in Shuanghe North II4-5 Block of Henan oilfield, a viewpoint that combination flooding including polymer flooding and polymer/surfactant compound flooding as well as micro-gel flooding enhances oil recovery is put forward. Based on numeral simulation result of combination flooding composing, oil displacement experiments are carried out in different penetration ratio natural core and artificial core. Experimental results show that combination flooding can enhance oil recovery factor after polymer flooding in Shuanghe North II4-5 Block, and oil recovery factor is high up to 13% in natural core or 15.7% in optimum injection velocity (14.2 m/d), its oil-displacement mechanism is increasing conformance efficiency and reducing interface tension between oil and water to 5.4 x 10 -3 mN/m to enhance displacement efficiency.