缝洞型储层酸压暂堵剂封堵性能研究

摘要

Large composite acid fracturing is the main stimulation method in the Tahe carbonate reservoirs.However,abundant naturally fractured vuggy systems result in serious acid leak-off.Using acidizing flow instrument at high temperature and pres-sure,experiments were carried out to evaluate the plugging performance of ceramic powder,fiber and oil-soluble resin,respec-tively.The maximum displacement pressure and temporary plugging time were tested at different mass of the temporary plugging agents.These three agents were evaluated from aspects of the reservoir damage,price,construction and effect of temporary plug-ging.Experimental results show that the maximum displacement pressure and plugging time increase as the mass of the tempora-ry plugging agent increases.When the mass of temporary plugging agent is 1 g,the maximum displacement pressure of oil-solu-ble resin is 10.67 times that of fiber and 14.38 times that of ceramic powder.Furthermore,the plugging time is 6.73 times lon-ger than that of fiber and 10.57 times longer than that of ceramic powder.Hence,the plugging properties of oil-soluble resin are much more prior to others.Oil-soluble resin can degrade at high temperature and flow along with flow-back liquid without dama-ging to reservoirs The experimental results have guiding significance in choosing temporary plugging agents of acid fracturing in the Tahe naturally fractured vuggy Carbonate Reservoirs.%针对塔河油田缝洞型碳酸盐岩大型复合酸压过程中液体滤失严重的现象，利用高温高压酸岩反应流动仪对粉陶、可降解纤维、油溶性树脂3种暂堵剂进行了室内实验，测得这3种暂堵剂在不同加量下的最大驱替压差和暂堵时间，并从暂堵效果、对地层伤害、价格和施工等方面评价了这3种暂堵剂。结果表明：加量越大，3种暂堵剂的最大驱替压差越大，暂堵时间越长；暂堵剂加量为1 g 时，油溶性树脂的最高驱替压差分别是可降解纤维和粉陶的10．67倍和14．38倍，暂堵时间分别为可降解纤维和粉陶的6．73倍和10．57倍，油溶性树脂的暂堵性能远优于可降解纤维和粉陶；但可降解纤维和油溶性树脂在高温下可降解，随返排液体流出地层，对储层造成的伤害较小。实验结果为塔河缝洞型碳酸盐岩储层酸压改造暂堵剂的选择提供一定的参考。