高温油藏条件下聚合物驱油效率实验—以泌阳凹陷双河油田为例

An experimental study of displacement efficiency of polymer flooding under high temperature reservoir conditions:an example from Shuanghe oilfield in the Biyang Sag

韩杰 张丽庆 周永强 汤达祯

Han Jie Zhang Liqing Zhou Yongqiang Tang Dazhen

针对泌阳凹陷双河V区块高温(84.3℃)低渗透的油藏条件,选取不同水解度的聚合物1630s和ZL-I进行驱油效率实验。通过不同浓度聚合物对驱油效率的影响实验发现,高浓度聚合物由于具有较高的粘弹性,驱油效率明显高于低浓度聚合物,但考虑到经济因素,建议注入浓度为1600～2000 mg/L。不同段塞尺寸驱替实验说明,注入大段塞聚合物比注入低段塞驱油效率更高,但超过0.5 PV时驱油效率提高缓慢,故段塞尺寸为0.4～0.5 PV。由聚合物老化前、后对比驱油实验得出,低水解度聚合物1630s更适合此高温油藏条件。

According to the characteristics of high temperature(84.3℃) and low permeability of reservoirs in the Shuanghe-V block of the Biyang Sag,polymers 1630s and ZL-I with different degrees of hydrolysis are selec-ted for an experiment on oil displacement efficiency.Thanks to its high viscoelasticity,displacement efficiency of high concentration polymers is obviously higher than that of low concentration polymers.However,considering the cost,polymers of 1 600-2 000 mg/L is proposed for use.An additional experiment on displacement efficiency of different slug sizes is conducted too.The results show that the displacement efficiency of bigger polymer slug is higher than that of smaller polymer slug.However,the incremental displacement efficiency is insignificant when the slug size exceeds 0.5 PV.Therefore,the suggested size of slug should be between 0.4 PV and 0.5 PV.Comparing the experiment results before and after the maturing of the polymers,we find that polymer 1630s with low degree of hydrolysis is more favorable for this high-temperature reservoir.

10.11743/ogg20090620