HPAM/酚醛凝胶体系的低温成胶性能改进

Gelation Improvement of Phenol-formaldehyde Cross-linking HPAM System at Low Temperature

杨卫华 葛红江 徐佳妮 程 静 袁肖肖 何丕祥

YANG Weihua GE Hongjiang XU Jiani CHENG Jing YUAN Xiaoxiao HE Pixiang

水溶性酚醛树脂与部分聚丙烯酰胺（HPAM）在低温环境需要促交剂配合才能反应形成冻胶，但是现有促交剂成胶速率过快且成胶强度远不及铬离子冻胶。本文通过实验筛选出含有大量伯、仲胺的阳离子聚合物GY，与甲醛、弱碱等物质复配得到促交剂GY-2；通过提高酚醛交联剂合成过程中的酚醛比、降低合成反应温度得到酚醛交联剂FQ-1；实验研究了矿化度对HPAM/FQ-1/GY-2凝胶体系成胶强度的影响，并考察了该凝胶体系的封窜能力及现场应用情况。GY的阳离子与HPAM的阴离子、交联剂中游离醛、低聚合度的羟甲基酚以离子吸附作用形成反应体系的微交联结构；GY中低温活性强的伯、仲胺可与HPAM中的部分酰胺基发生反应，增强HPAM低温下的共价交联反应活性；FQ-1更低聚合度的羟甲基酚可减缓酚醛交联剂树脂化自聚反应速率。HPAM/FQ-1/GY-2凝胶体系在矿化度3000~10000 mg/L下的成胶强度为20000~80000 mPa·s，成胶时间为24~120 h可调，抗盐性能较好。该凝胶体系在现场矿场应用效果良好，现场调剖10口井，12个月平均单井累计增油350 t。图5表2参14

As a polymer crosslinker，water-soluble phenolic resin need to cooperate with a promoter to react with HPAM to form gel at low temperature. However，the existing promoter used was not appropriate，by which the gel reaction is too fast and the gel strength is far less than that of the chromium ion gel frequently reported. To solve the shortcomings above，the promoter GY-2 was prepared with formaldehyde，weak alkali and a cationic polymer GY containing a large number of primary and secondary amines.The phenolic resin cross-linking agent FQ-1 was obtained by increasing the mole ratio of phenol to formaldehyde and reducing the reaction temperature in its synthetic process. Further，the influence of salinity on the gelation strength of HPAM/FQ-1/GY-2 gel system was studied，and the sealing ability and field application of the gel system were investigated. The cations of GY reacted withthe anions of HPAM，the free aldehyde in the crosslinking agent，and the hydroxymethylphenol with low degree of polymerization，forming the micro crosslinking structure of the reaction system by ion adsorption; the primary and secondary amines of GY with strong activity at low temperature reacted with some amides in HPAM，enhancing the covalent crosslinking activity of HPAM at low temperature; the hydroxymethylphenol of FQ-1with lower polymerization degree could slow down autopolymerization rate of the phenolic crosslinking agent resin. The gel strength of HPAM/FQ-1/GY-2 gel system was 20000—80000 mPa·s under the salinity of 3000—10000 mg/L，the gelation time was 24—120 h，and the salt resistance was good. The HPAM/FQ-1/GY-2 gel system had good application results in the field. 10 wells in the field were profile-controlled，and the average increasing oil of a single well was 350 tons in 12 months.

10.19346/j.cnki.1000-4092.2019.04.012