新型疏水缔合压裂液稠化剂HLCW的合成与性能评价

Synthesis and performance evaluation of new hydrophobic associative fracturing fluid thickener HLCW

关键词:  疏水缔合  稠化剂  抗剪切  减阻  防膨  悬砂

Key words:  hydrophobic association  thickener  shear resistance  drag reducing  anti-expansion  sand suspension

摘要:

目的 针对目前页岩油开发中单一功能压裂液体系存在的不足，开发一种多功能性新型稠化剂。方法 以丙烯酰胺、N–苄基–N–甲基丙烯酰氧基–N，N–二甲氨基氯化铵（MTC）、聚（乙二醇）二十二烷基醚甲基丙烯酸酯（BEM）为原料，以2，2–偶氮二异丁基脒二盐酸盐（V50）聚合物为引发剂，制备了一种新型的疏水缔合型稠化剂（HLCW）。对产物进行红外、核磁结构表征，以及表观黏度、耐温耐剪切、防膨、减阻、抗盐、悬砂与破胶性能评价。结果 该稠化剂的临界缔合质量分数为0.5%，此条件下的表观黏度为181.50 mPa·s。在120 ℃下，以固定剪切速率170 s^-1剪切1.5 h，质量分数为0.5%的稠化剂HLCW水溶液最终表观黏度为78.96 mPa·s。常温下，清水配制质量分数为0.0125%稠化剂HLCW水溶液的减阻率为73.96%。当质量分数超过0.3%时，HLCW水溶液的防膨率高达80%。破胶后，破胶液澄清透明，残渣含量远低于行业标准。结论 HLCW具有良好的增稠效果，并具有抗高温、耐剪切、耐盐性能，低含量溶液可用作减阻剂，高含量溶液可用作增稠剂。有较好的防膨效果，与相对分子质量为1000×10⁴阳离子型聚丙烯酰胺相比，稠化剂HLCW表现出优异的悬砂性能，具备一定的油田工业应用前景。

Abstract:

Objective Aiming at the deficiencies of the single-function fracturing fluid system in the current shale oil development, this paper develops a new multifunctional thickener. Method A new hydrophobic associative thickener, HLCW, was prepared from acrylamide, N-benzyl-N-methacryloyloxy-N,N-dimethylammonium chloride (MTC), and poly(ethylene glycol) docosyl ether methacrylate (BEM) using 2,2-azobisisobutylamidinium dihydrochloride (V50) polymer initiator. The product was characterized by infrared spectroscopy and nuclear magnetic structure, and evaluated for apparent viscosity, temperature and shear resistance, anti-expansion, drag reduction, salt resistance, sand suspension and gel breaking properties. Result The critical associating concentration of the thickener was 0.5 wt%, and its apparent viscosity under this condition was 181.5 mPa·s. After shearing at a fixed shear rate of 170 s^-1 at 120 ℃ for 1.5 h, the final apparent viscosity of the aqueous solution of 0.5 wt% thickener HLCW was 78.96 mPa·s. At room temperature, the drag reduction rate of 0.012 5 wt% thickener HLCW formulated in clear water was 73.96%. When the mass fraction exceeded 0.3%, the anti-expansion rate of the thickener aqueous solution was as high as 80%. After breaking the gel, the broken gel solution was clarified and transparent, and the residue content was much lower than the industry standard. Conclusion The thickener HLCW has good thickening effect, high temperature resistance, shear resistance, salt resistance, and is used as a drag reducing agent in low concentration and thickener in high concentration. It has good anti-expansion effect, and compared with cationic polyacrylamide with relative molecular mass of 10 million, the thickener HLCW shows excellent sand suspension performance, and has certain prospects for oilfield industrial application.