超临界二氧化碳增稠剂溶解性实验评价*

Solubility Evaluation of Supercritical Carbon Dioxide Thickener

翟怀建 张景臣 董景锋 王 佳 张凤娟 李晓枫

ZHAI Huaijian ZHANG Jingchen DONG Jingfeng WANG Jia ZHANG Fengjuan LI Xiaofeng

超临界二氧化碳（CO2）黏度不足0.1 mPa·s，在加砂压裂中携砂困难，需添加增稠剂增大其黏度。鉴于增稠 剂在CO2中的溶解性与其增黏效果密切相关，对比研究了聚合物ZCJ-01、表面活性剂微乳液APRF-2和表面活性 剂乳液SC-T-18 3种增稠剂在液态、超临界CO2和水中的溶解性，利用Chrastil半经验模型对溶解度实验数据进行 线性关联，并对比理论值，最后分析了增稠剂在超临界CO2中的溶解性受压力、温度的影响规律。结果表明，溶 解性最好的增稠剂为SC-T-18，其与超临界CO2在充分搅拌后形成单一、稳定、均相的乳状胶束。3种增稠剂在 CO2中的溶解度实验值与理论值的相对偏差小于5%，实验测量值较为准确。随着压力和温度的增加，3种增稠 剂在CO2中的溶解度也增大，满足现场施工要求。图5表1参24

The viscosity of supercritical carbon dioxide（CO2）is less than 0.1 mPa·s. It is difficult to carry sand in fracturing， which needs thickener to increase its viscosity. Considering that the solubility of thickener in CO2 was closely related to its viscosity enhancement effect，the solubility of polymer ZCJ-01，surfactant microemulsion APRF-2 and surfactant emulsion SC-T-18 in liquid CO2，supercritical CO2 and water was comparatively studied. The experimental data of solubility was linearly correlated by using Chrastil semi-empirical model，and compared with the theoretical value. Finally，the influence law of temperature and pressure on the solubility of thickener in supercritical CO2 was analyzed. The results showed that the thickener with the best solubility was SC-T-18，and it formed a single，stable，homogeneous emulsion micelle with supercritical CO2 after full stirring. The relative deviation of solubility between experimental value and theoretical value of the three thickeners in CO2 was less than 5%，and the experimental value was relatively accurate. The solubility of three thickeners in CO2 increased with the increase of temperature and pressure，which met the requirement of fracturing operation.

10.19346/j.cnki.1000-4092.2021.03.008