CAJ | 학술논문

高质量浓度聚合物具有较强的黏弹性，但应用中有时会出现聚合物分子聚集体尺寸与油藏岩石孔隙配伍性较差的问题。针对大庆油田储层地质特征和流体性质，通过岩心流动性实验和驱油实验，以渗流特性为评价指标，利用正交试验优选出分子内交联聚合物凝胶体系后，研究凝胶体系黏弹性和驱油效率。结果表明：调节聚合物质量浓度、配制水矿化度、w(聚/Cr3+)可获得分子聚集体尺寸较小且阻力系数和残余阻力系数较高的分子内交联聚合物凝胶体系。聚合物溶液发生分子内交联后，一方面聚合物分子线团传输运移能力增强，且刚性增强，通过岩心孔隙时形变能力减弱，滞留能力增强，可有效提升注入压力，扩大波及体积；另一方面体系黏弹性和第一法向应力差均增大，洗油效率提高，二者综合作用表现出较高的驱油效率。
고질량농도취합물구유교강적점탄성，단응용중유시회출현취합물분자취집체척촌여유장암석공극배오성교차적문제。침대대경유전저층지질특정화류체성질，통과암심류동성실험화구유실험，이삼류특성위평개지표，이용정교시험우선출분자내교련취합물응효체계후，연구응효체계점탄성화구유효솔。결과표명：조절취합물질량농도、배제수광화도、w(취/Cr3+)가획득분자취집체척촌교소차조력계수화잔여조력계수교고적분자내교련취합물응효체계。취합물용액발생분자내교련후，일방면취합물분자선단전수운이능력증강，차강성증강，통과암심공극시형변능력감약，체류능력증강，가유효제승주입압력，확대파급체적；령일방면체계점탄성화제일법향응력차균증대，세유효솔제고，이자종합작용표현출교고적구유효솔。
Although high-concentration polymer has strong viscoelasticity, there exist the compatibility problems between pol-ymer molecules aggregate size and reservoir rock pore size during its practical application. According to the geological charac-teristics and fluid properties of Daqing Oilfield reservoir, the viscoelasticity and oil displacement efficiency of the intramolec-ular cross-link polymer gel system were investigated after it was selected by orthogonal experiment through evaluating seepage characteristics, with core flow experiment and oil displacement experiment. It was found that intramolecular cross-link poly-mer gel system with smaller molecular aggregate, higher resistance coefficient and residual resistance coefficient can be ob-tained by regulating polymer concentration, water solution salinity and polymer/Cr3+. Once intramolecular cross-link reacted in polymer solution, on the one hand, transmission migration ability of polymer molecular clew is enhanced, and its rigidity is also improved. In this way, deformation ability of the polymer molecular clew is weakened when it flows through core pore, which can enhance the retention ability, increase the injection pressure and enlarge sweep volume effectively. On the other hand, the viscoelasticity and first normal stress difference of polymer gel system are improved, as well as the washing oil effi-ciency. The above two aspects insure jointly Cr3+ polymer gel has higher oil displacement efficiency.