稠油注CO_2的方式及其驱油效果的室内实验

LABORATORY EVALUATION ON DISPLACEMENT EFFICIENCY OF SEVEN SCHEMES OF CO_2 INJECTION IN HEAVY OIL RESERVOIR

针对地层条件下粘度为 10 0mPa·s的稠油 ,采用室内实验方法研究了稠油注CO2 的注入方式 ,包括CO2吞吐、CO2 吞吐转CO2 驱转水驱、CO2 吞吐转水驱、CO2 驱、水驱CO2 段塞、CO2 水交替注入等 ,并对各种注入方式的驱油效率进行了比较。结果表明 ,在实验条件下 ,CO2 水交替注入和CO2 吞吐转水驱的方式驱油效率最高 ,稠油CO2 吞吐然后转为水驱的方式是可行的。该研究可为现场选择合理的注入方式提供技术参数。

Some experiments on seven schemes of CO 2 injection are conducted using heavy oil with 100 mPa·s viscosity to evaluate the effect for enhancing oil recovery with CO 2 in heavy oil reservoir under reservoir condition. The schemes include CO 2 huff n puff, CO 2 huff n puff followed by CO 2 and water drive, CO 2 huff n puff followed by water drive, water alternating CO 2 injection (WAG), water drive, CO 2 drive, displacement of CO 2 slug by water. It is found that WAG and huff n puff followed by water drive are the two best injection modes for heavy oil reservoir with viscocity of 100 mPa·s. It is concluded that CO 2 huff n puff followed by water drive is a potential engineering scheme for improving oil recovery.