S7断块驱油用阴/非离子表面活性剂性能评价

Evaluation of Anion/Nonionic Surfactant Used for EOR in S7 Block with Low Permeability Reservoir

针对S7断块低渗透油藏特征,开发出驱油用阴/非离子表面活性剂SHSA-JS,并对其进行性能研究.结果表明,在温度为83℃,SHSA-JS溶液浓度窗口为0.05％～0.6％,注入水矿化度为1 000～25 000 mg/L、二价离子（Ca2＋,Mg2＋）含量为2 410 mg/L的条件下,SHSA-JS可使油水界面张力达到10-2 mN/m数量级;储层净砂和石英砂对0.3％ SHSA-JS溶液的静态吸附量分别为4.50 mg/g和0.32 mg/g;静态洗油效率在41.8％以上,0.3％ SHSA-JS溶液注0.4 PV孔隙体积后可在水驱基础上平均提高采收率7.71％.该表面活性剂可满足S7断块低渗透油藏对驱油用表面活性剂的要求.

Aiming at the characteristic of low permeable oil reservoir in $7 Block, a new anionic/noniouic surfactant SHSA - JS for flooding was developed and its performances were evaluation. The results showed that SHSA -JS surfactant had good abilities of high temperature - resistance and salt - tolerance. The interfacial tension could decrease to l0-2 mN/m when the mass fraction of SHSA - JS was 0.05% -0.6%, salinity of the water was 1 000 -25 000 mg/L, the concentration of divalent ion （Ca^2＋ , Mg^2＋ ） was 2 410 mg/L, and the temperature was 83 ℃. The static adsorptive capacity of 0.3% SHSA - JS solution on reservoir sands and silica sands were 4.50 mg/g and 0.32 mg/g respectively. The static oil - washing rate of SHSA - JS surfactant was more than 41.8%. The resuhs of simulated flow flooding experiment （ enhance oil recovery） could be 7.71% by injecting 0.4 PV of 0.3% SHSA showed that the average EOR -JS surfactant on the basis of water- flooding. So SHSA -JS surfactant could be used as a displacing agent in S7 Block.