老君庙油田H184井组胶束/聚合物驱油先导试验

Micellar polymer flooding pilot test in H 184 well group, Laojunmiao oil field.

Ｈ１８４井组位于玉门老君庙油田Ｌ油藏顶部，由１口注入井和４口采油井构成反五点井网，井点圈定面积为９２４７ｍ２，采出程度已达４６％，含水高于９９％。该井组Ｌ油层富含钙、镁离子并亲油，数量很少的残余油呈油膜覆于岩石颗粒表面，针对此特点，先导试验注入分３个阶段：碱性溶液预冲洗（为使Ｌ油层形成碱性环境，降低驱油剂的损失）；注入胶束溶液；分４段注入聚丙烯酰胺溶液。该次先导试验总增产原油４３１ｔ，采油动态反映驱油前缘推进均匀，体积波及系数较高；但驱油剂洗油效果不佳，原因是胶束溶液段塞未形成超低界面张力，加之表面活性剂油溶性太强，油未形成流动相；总投入产出比为１０∶１，化学剂费用占总费用的６６．７％，经济效益不佳。提高Ｌ油层采收率主要应提高驱油剂的洗油效率，需研制低价格、高效能的化学剂，因此老君庙油田不宜用先导试验所用胶束／聚合物驱油。图４参２（郭海莉摘）

H 184 well group is located at the top of L reservoir of Laojunmiao oil field, consisting of 1 injection well and 4 production wells forming on inverted 5 spot pattern, covering an area of 9247m 2, with a current recovery efficiency of 46% and a production water cut of 99%. Pay Zone L in this well pattern is rich in Ca 2+ and Mg 2+ ions, the reservoir rock is oil wet and oil remaining in the reservoir is in the form of films on the rock particles. With this characteristics, pilot test is divided into 3 parts: preflushing with alkaline solution (to form an alkaline environment to decrease the loss of oil driving agent in L zone); injecting micellar slug, followed by injection of polyacrylamide solution in 4 slugs. 431t of oil are obtained in this pilot test. Production behavior showed that uniform advance of the driving front was observed accompanied by a high volumetric sweep efficiency but inferior oil driving efficiency. This is because ultralow interfacial tension was not appeared. In addition, concentration of surfactant is above 95%, and oil flow phase was not formed. Total input/output ratio equals 10∶1, and cost of chemical agent is 66.7% in the total cost, thus economic benefit is not good. Therefore, to enhance the oil recovery in this reservoir should put stores on the oil driven efficiency of the chemical agent. A low cost, high efficient chemical agent should be used by further study and research work. Those agents used currently will not be applied further. Subject