非交联酸化自转向剂ADDA的合成及转向性能评价

Synthesis and diverting performance evaluation of non-crosslinked acidification self-diverting agent ADDA

利用丙烯酰胺(AM)、3-(N,N-二甲氨基丙基)甲基丙烯酰胺(DMAPMA)、十八烷基二甲基烯丙基氯化铵(DMAAC-18)和4-丙烯酰吗啉(ACMO),通过自由基水溶液聚合得到了一种初始黏度低,并随着酸岩反应自动增稠的酸化自转向剂ADDA。通过单因素实验得到ADDA的最佳合成条件为:单体配比n(AM)∶n(DMAPMA)∶n(DMAAC-18)∶n(ACMO)=90∶10∶1.8∶10,引发剂含量(以单体总质量为基准,下同)为0.5%,单体含量(以单体溶液总质量为基准,下同)为30%,反应温度55℃,反应时间6 h,pH=7。利用FTIR和1HNMR对产物结构进行确证。在90℃下,1.3%(以HCl溶液总质量为基准,下同)ADDA酸液黏度能从ADDA鲜酸的6 mPa·s增加到126 mPa·s,具有较好的转向性能。1.3%ADDA残酸在90℃、170 s^(–1)下剪切1 h后,其表观黏度为70m Pa·s,表明ADDA残酸具有较好的抗温性能。在90℃下,与不加入酸化外加剂的1.3%ADDA自转向酸相比,加入铁离子稳定剂、助排剂和高温缓蚀剂的酸化外加剂后,1.3%ADDA自转向酸残酸表观黏度提高了54 mPa·s,表明ADDA配伍性良好。

An acidizing self-diverting agent ADDA with low viscosity and automatic thickening with acid rock reaction was obtained by free radical aqueous solution polymerization of acrylamide(AM), 3-(N,Ndimethylaminopropyl)methylacrylamide(DMAPMA), octadecyldimethylallylammonium chloride(DMAAC-18) and 4-acryloylmorpholine(ACMO). The optimal conditions for the synthesis of ADDA were obtained by single factor of experiment as follow: n(AM)∶n(DMAPMA)∶n(DMAAC-18)∶n(ACMO) = 90∶10∶1.8∶10, initiator dosage(based on the total mass of monomers, the same below) of 0.5%, monomer content(based on the total mass of monomer solution, the same below) of 30%, reaction temperature of 55 ℃, reaction time of 6 h and system pH of 7. The structure of product was characterized by FTIR and 1HNMR. At 90 ℃, the apparent viscosity of 1.3%(based on the total mass of HCl solution, the same below)ADDA acid viscosity increased from 6 mPa·s of ADDA fresh acid to 126 mPa·s, which had good diverting performance. The apparent viscosity of 1.3% ADDA spent acid was 70 mPa·s after shearing at 90 ℃ for 1 h at 170 s^(–1), indicating that ADDA spent acid had good temperature resistance. At 90 ℃, the apparent viscosity of 1.3% ADDA self-diverting acid of spent acid with iron ion stabilizer, drainage aid and high temperature corrosion inhibitor was increased by 54 m Pa·s compared with that 1.3% ADDA without acidification admixture, indicating that ADDA processed good compatibility.