基于聚驱控制程度的二类油层聚驱参数确定

Determination of polymer flooding parameters of the second type reservoirs based on polymer flooding control extent

主力油层聚合物驱油设计方案应用水驱控制程度概念，仅在单井日注人量上存在差异，这种方法不适应非均质性严重的二类油层，因此，建立了聚驱控制程度的概念，用来表征不同渗透率分级下井网对油层的聚驱控制程度．根据聚驱控制程度确定二类油层聚驱参数，模拟试验结果表明：该方法适应二类油层发育的地质特征，聚驱见效特征明显，预计提高采收率可超过8．2％；萨中开发区注采井距应为125～175m，聚合物相对分子质量应为1200×10^4～^700×10^4；单井年注入速度和聚合物溶液质量浓度应根据聚驱控制程度个性化确定．

Water flooding control extent was applied in major reservoirs, only the daily solution-injection rate is different between injection wells.For the serious heterogeneity of the second type reservoirs,the polymer flooding conceptual design with major reservoir can not be applied with it.The concept of polymer flooding control extent is built to express the polymer flooding control extent,considering different permeability graduation.Polymer flooding parameters of the second type reservoirs are decided according to the concept.The result of simulation test indicted that this method is applicable to geological property of the second type reservoirs,responding characteristic of polymer flooding is obvious,and the recovery efficiency is expected to be improved by 8.2 percent.In Sazhong oilfield,polymer flooding parameters of the second type reservoirs are optimized,the well spacing is defined as 175～125 m,the relative molecular mass of polymer is defined as 1 200×10~4～1 700×10~4.Based on polymer flooding control extent,the injection rate and the mass concentration of polymer are defined according to the characteristic of every well group individual.