HSG冻胶调剖堵水剂室内评价

针对吉林油田低渗透、裂缝油藏注水开发后期注水窜流严重的特点,研制出新型冻胶调剖堵水剂HSG。对HSG成胶前溶胶体系的表观黏度影响因素进行了分析,分析认为在相同剪切速率下溶胶体系表观黏度随共聚物浓度、矿化度、碱含量的增加而增大,并表现出剪切稀释特性,黏温测试表明溶胶体系表观黏度随温度升高而下降;对HSG成胶后冻胶体系的强度进行了测定,确定其屈服应力值为3500 Pa,振荡剪切应力扫描确定了冻胶体系的线性黏弹性区域,频率扫描确定该冻胶为强冻胶体系;2组并联填砂管选择注入试验表明,HSG溶胶体系具有良好的选择注入能力,能达到优先进入高渗透层的目的;20 m超长填砂管封堵试验表明,HSG溶胶体系的注入压力梯度为0.82 MPa/m,具有易于注入的特点,HSG成胶后的封堵强度为17.54 MPa/m,具有较强的封堵能力。该研究为HSG冻胶调剖堵水剂现场应用提供了借鉴。

Laboratory evaluation of HSG profile modification gel

According to the characteristics of low permeability and fracturing reservoirs in Jilin Oilfield,a compound profile modification agent called HSG was developed in EOR Center of China University of Petroleum.The apparent viscosity of HSG sol rises with increased copolymer,salinity and alkali concentration under the same sheer rate.The HSG sol also had a property of shear thinning.Viscosity vs.temperature test showed its apparent viscosity decreased with increased temperature.The yield stress of HSG gel was 3500 Pa.Linear viscoelasticity area was determined by oscillation shear sweep test and strong gel property of this sol was shown.The injection test of two parallel connection sand-packed pipes showed that the sol had the attribute of preferentially entering high permeability zone.Profiling experiment with 20-meter sand-packed pipe showed the injection pressure gradient of this sol was 0.82 MPa/m,and the gel had a strong shut-off property with a shut-off intension of 17.54 MPa/m.