【摘要】 针对大庆喇嘛甸聚合物驱油藏,研究了注入絮凝剂利用地层残留聚合物的方法,实验温度45℃,用大庆油田采油污水配液。根据絮凝沉降量选择稳定化钠土YG866为絮凝剂,根据流变参数n,K和黏度,确定水分散体中YG866质量分数为3%～5%。通过混合沉降实验确定,浓度50～1000mg/L的聚合物HPAM水溶液均可被YG866絮凝,浓度200～600mg/L时絮凝效果较好。在填砂管中注入5%YG866水分散体,残余阻力系数为2.05,当填砂管中存有400mg/L的聚合物溶液时增至10.41。原子力显微镜观测表明,一个黏土片可与4～7个聚合物分子结合。2007年8月在喇嘛甸油田有6口注入井的4-P1920井区进行现场试验,平均单井注入5%YG866水分散体5160m3,折合YG866产品140t,对应13口油井均见效,单井日产液量增加8.7t,日产油量增加3.6t,含水由93.3%降至90.8%,产聚量由459mg/L降至370mg/L,至2008年3月仍处于有效期。更多还原

【Abstract】 Aimed at polymer flooded oil reservoirs in Lamadian,Daqing,a technology of reusing polymer existing in reservoir formations by the way of flocculant injection was investigated at 45℃ with working fluids prepared in a Daqing produced water.The flocculant chosen was a stabilized sodium bentonite(SSB),YG866,which caused the largest amount of polymer precipitates;3—5% YG866 dispersion in water had optimal rheologic characteristics n,K,and apparent viscosity.In a precipitation experiment its was shown that polymer HPAM could be flocculated and precipitated by YG866 from aqueous solution of polymer concentration 50—1000 mg/L and the flocculation and precipitation were more effective at polymer concentration 200—600 mg/L.The residual resistance factor for 5% YG866 dispersion determined in a sand packed tubes without and with 400 mg/L polymer solution existed was of 2.05 and 10.41,respectively.The observations under atomic force microscopy demonstated that 4—7 polymer chains might be adsorbed on a single clay platelet.In a field trial conducted in an area of 4-P1920 block covering 6 injection and 13 production wells Aug 2007,5160 m3 of 5% YG866 dispersion,or 140 t of commercial product YG866,was injected per well and all the 13 production showed positive responses,which did not vanish in March 2008 and were demonstrated by following data:daily fluid and oil output rise of 8.7 and 3.6 t,respectively,watercut drop from 93.3% to 90.8%,and polymer production drop from 459 to 370 mg/L.更多还原