高温高渗油藏堵水剂封堵效果实验研究

Experimental Study on Plugging Effect of Water Shutoff Agent in High Temperature and Permeability Reservoir

对于非均质性严重的油藏,油水井堵水调剖是稳油控水和提高采收率的重要技术手段之一。目前我国多数油田已经进入高含水或特高含水开采后期,堵水调剖剂的选择更显得尤为重要,提高水驱效率和石油采收率也更加受到人们的重视。针对矿场实际需求,以高渗储层地质特征和流体性质为模拟研究对象,开展了不同体系及浓度堵水剂的性能评价及对LH储层封堵效果影响实验研究。实验结果表明,对于目标储层不同浓度的聚合物微球的突破压力较小,注入能力整体较好,可注入浓度小于5%,但封堵效果较差,封堵率仅为75%。聚合物凝胶成胶反应主要发生在6 h以后,岩心封堵率接近100%。"聚合物凝胶+微球"组合的注入压力较高,突破压力较大,封堵效果较好,封堵率为99.5%,在保证有效封堵岩心的前提下可以大幅度降低凝胶的使用量,减小对地层污染。

Water plugging and profile control in oil and water wells has been an important technique for controlling water and oil production and enhancing oil recovery in heterogeneous reservoirs. At present, most oilfields in China have entered the late stage of high or ultra-high water cut production, and the selection of water plugging and profile control agent is becoming more and more important. More attention has been paid to improving water drive efficiency and oil recovery. In this paper, according to the actual requirement of field production, taking the geological characteristics and fluid properties of high permeability reservoirs as simulation objects, the performance evaluation of water plugging agents with different systems and concentrations was carried out, and their plugging effect on LH reservoir was studied. The results showed that the breakthrough pressure of polymer microspheres with different concentration was small, the injection ability was good as a whole, and the injectable concentration was less than 5%, but the plugging effect was poor, and the plugging rate was only 75%.Gelling reaction of polymer gel occurred mainly after 6 h. and core plugging rate was close to 100%.The combination of "polymer gel + microsphere" has a higher injection pressure, higher breakthrough pressure and better plugging effect, with a plugging rate of 99.5%. On the premise of effectively plugging core, the usage of gel can be greatly reduced and formation pollution can be reduced.