油井堵水用高强度PEI冻胶研究*

Research on High-strength PEI Gel Used for Oil Well Water Plugging

赵 赛 葛际江 朱 杰 张洪海

ZHAO Sai，GE Jijiang，ZHU Jie，ZHANG Honghai

实验采用丙烯酰胺与丙烯酸叔丁酯的共聚物（PAtBA）与聚乙烯亚胺（PEI）制备成胶液，从冻胶高强度的角 度出发，着重研究了聚合物用量、交联剂用量与分子量、温度、盐含量以及pH值对成胶性能的影响。研究结果表 明，随着聚合物、交联剂含量的增加，冻胶强度增加。在pH值为6～9时，随着pH值的增大，冻胶成胶时间延长； pH值为9～12时，pH值越大，成胶时间越短。当成胶液中盐含量增加时冻胶成胶时间延长，冻胶强度先增高后 降低。成胶时间与温度的关系符合Arrhenius公式，反应所需活化能为48.36 kJ/mol。5% PAtBA+1.5% PEI的冻 胶体系在110 ℃下所形成冻胶的储能模量可以达到2689.2 Pa。该冻胶体系的耐温良好，在170℃环境中保持I级 的时间＞30 d。此外，与铬冻胶和酚醛类冻胶相比，PEI冻胶的毒性低，更加适用于海上油田。图10表1参14

In order to meet the high strength requirement，acrylamide/tert-butyl acrylate Copolymer（PAtBA）and crosslinking agent polyethyleneimine（PEI）was used to prepare the gellant，the influence of the content of polymer，the content and molecular weight of crosslinking agent，temperature，salt content and pH on the gelation was emphatically studied. Experimental results showed that gel strength was positively correlated with the content of polymer and crosslinking agent. When the pH value was in range of 6—9，as the pH value increased，the gelation time was prolonged；when the pH value was in the range of 9—12，as the pH value increased，the gelation time was shortened. With the salt content increased，the gel strength would first increase and then decrease. The relationship between gelation time and temperature conformed to the Arrhenius formula，the activation energy required for the reaction was 48.36 kJ/mol. Storage modulus of the gel formed at the temperature of 110℃，which was composed of 5% PAtBA and 1.5% PEI，could reach up to 2689.2 Pa. The gel strength could maintain I level for more than 30 days at the temperature of 170 ℃，indicating that PEI gel had excellent temperature resistance. In addition，compared with chrome gel and phenolic gel，PEI gel had low toxicity and was more suitable for offshore oilfields.

10.19346/j.cnki.1000-4092.2021.03.010