南中块西部聚驱后注入方式优化研究

Uptimigation Research of Injection Pattern after Flooding for the West of Central South Block

南中块西部于2004年7月份开始注聚,到2009年底该区块聚合物驱开发结束时,聚驱阶段提高采收率11.6%,采出程度只有50.34%,地下仍有近一半的储量没有开采出来。从喇嘛甸油田一类油层直接转入后续水驱区块效果看,无效循环严重,采收率提高幅度只有3.61%。为最大限度地改善区块开发效果,在砂体精细解剖基础上,结合注聚后期剩余油分布特点,开展聚驱后注入方式研究。

Polymer injection begun in July,2004 in the west of central south block and ended at the end of 2009.Oil recovery ratio during this period had increased 11.6 percent,but the total recovery is only 50.34 percent,which means nearly half of the oil in the reservoir was unexploited.Effect of directly diverting to water flooding after polymer flooding in the same kind of formation in Lamadian oilfield was compared and severe invalid circulation was found with an increase of only 3.61 percent of the recovery ratio.For the maximum recovery of this block,a research on the injection method after polymer flooding is conducted on the basis of fine dissection of the sand body research results and analysis of residual oil distribution after polymer flooding.