论文部分内容阅读
弱凝胶是由低浓度部分水解聚丙烯酰胺(HPAM)与柠檬酸铝形成的交联体系。提出了一种新的快速有效的评价弱凝胶的方法,即用核微孔滤膜模拟油藏的微孔介质,以弱凝胶通过核微孔滤膜的能力对其形成机理及封堵性能进行评价。研究了在聚铝比(HPAM质量与Al质量比)确定的情况下,HPAM的相对分子量、矿化度、钙镁离子含量对弱凝胶封堵性能的影响。实验结果表明,随着HPAM的相对分子质量的增大,HPAM与AlCit反应形成的弱凝胶通过核微孔滤膜过滤的时间延长,对核微孔滤膜的封堵程度增大。不含有电解质同样可以对多孔介质形成有效封堵,但其封堵效果低于含有适量电解质的弱凝胶体系的封堵效果。
Weak gels are cross-linked systems formed from low concentrations of partially hydrolyzed polyacrylamide (HPAM) and aluminum citrate. A new rapid and effective method for evaluating weak gel is proposed, which is to use nuclear micropore membrane to simulate microporous media in reservoirs, to form mechanism and blockade the ability of weak gel to pass through nuclear micropore membrane Performance evaluation. The effects of relative molecular weight, salinity, calcium and magnesium ion content of HPAM on the performance of weak gel plugging were studied under the condition of the ratio of polyamines to aluminum (HPAM mass to Al mass ratio). The experimental results show that with the increase of relative molecular mass of HPAM, the weak gel formed by the reaction of HPAM and AlCit passes through the nuclear micropore membrane for an extended period of time, and the plugging degree of the nuclear micropore membrane increases. The absence of electrolyte also can effectively block the formation of porous media, but the blocking effect is lower than that of the weak gel system containing appropriate electrolyte.