凝胶型选择性堵水剂DQ-2的研制及应用

以改性聚丙烯酰胺为主要原料,配以交联剂和稳定剂,制得选择性堵水剂DQ-2.优选出选择性堵水剂DQ-2的最佳配方:0.6%改性聚丙烯酰胺+0.6%交联剂+0.03%稳定剂.采用瓶试法成胶实验和岩心流动实验评价了DQ-2体系的各项性能.实验结果表明:DQ-2堵水剂耐温30～70℃;抗矿化度性能良好,对K+和Na+的容忍度可以达到10 000 mg/kg,对Ca2+和Mg2+的容忍度可以达到5 000 mg/kg;对不同渗透率的岩心,堵水率达到90%,突破压力梯度大于10 MPa/m,堵油率小于30%,突破压力梯度低于1 MPa/m,具有较好的油水选择性.DQ-2体系的这些性能指标均达到了长庆油田现场应用的要求,实现了对水淹油井的有效治理,取得了较好的经济效益.

Development and application of a selective gel plugging agent DQ-2

A selective plugging agent DQ-2 was prepared by using modified polyacrylamide as main material and adding crosslinking agent and stabilizer.Its optimum composition was modified polyacrylamide of 0.8%,crosslinking agent of 0.6% and stabilizer of 0.03%.The performance of DQ-2 system was evaluated by gelling experiment and core flow experiment.The results show that the DQ-2 system can tolerate the temperature of 30~70℃,K+ or Na+ concentration of 10 000 mg/kg and Ca2+ or Mg2+ concentration of 5 000 mg/kg.To the cores of different permeability,the plugging rate to water can reach 90%,breakthrough pressure gradient is greater than 10 MPa·m-1,while the plugging rate to crude oil is less than 30%,breakthrough pressure gradient is less than 1 MPa·m-1.DQ-2 system has good selectivity to oil and water plugging,and it can meet the needs of Changqing Oilfield to the property of plugging agent.Application of DQ-2 system effectively solves the waterflooding of oil wells in Changqing Oilfield,and good economic benefit may be get.