红河油藏封堵裂缝用酚醛冻胶的制备与性能评价

Preparation and Performance Evaluation of Phenolic Gel Using for Plugging Cracks in Honghe Reservoir

为封堵红河长8油藏的直通型水窜裂缝,以部分水解聚丙烯酰胺G3515为成胶剂、水溶性酚醛树脂为交联剂、氯化铵为催化剂,制备了成胶时间与强度不同的冻胶,评价了冻胶的稳定性、注入性和封堵能力。结果表明,冻胶的稳定性较好,由0.5%G3515、0.5%水溶性酚醛树脂、0.2%催化剂和0.3%纳米颗粒QC-W配制的冻胶在70℃下放置180 d的弹性模量大于10 Pa。冻胶的注入性良好,成胶液在70℃下的黏度低于500 mPa·s。冻胶的封堵能力较好,含0.8%G3515的强冻胶在直径为0.7数1.8 mm细管中的突破压力梯度达到4 MPa/m以上,含0.3%G3515的弱冻胶在直径为0.7数1.5 mm细管中的突破压力梯度达到1 MPa/m以上,满足红河油田大剂量注入的要求。

In order to block the straight-through water channeling fractures of Honghe Chang 8 reservoir,gels with different gelling time and strength were prepared by using partially hydrolyzed polyacrylamide G3515 as gelling agent,water-soluble phenolic resin as cross-linking agent,and ammonium chloride as catalyst.The stability,injection and plugging capacity of gel was evaluated.The results showed that the stability of the gel was good.The elastic modulus of the gel prepared by 0.5%G3515,0.5%water-soluble phenolic resin,0.2%catalyst and 0.3%nanoparticle QC-W after placing 180 days at 70℃was greater than 10 Pa.The injection of jelly was good,and the viscosity of the gel-forming solution at 70℃was less than 500 mPa·s.The blocking ability of the gel was good.The breakthrough pressure gradient of the strong gel containing 0.8%G3515 in a thin tube with a diameter of 0.7—1.8 mm was above 4 MPa/m,and that of the weak gel containing 0.3%G3515 in a thin tube with a diameter of 0.7—1.5 mm was above 1 MPa/m,which met the requirement of large dose injection in Honghe oilfield.