高温油藏聚合物凝胶的制备及其暂堵性能

Preparation and Temporary Plugging Performance of Polymer Gel for High-temperature Reservoirs

王 刚 王仕伟 何丹丹 卢仁玲 吴 娟 赖 璐

WANG Gang WANG Shiwei HE Dandan LU Renling WU Juan LAI Lu

为满足高温油藏作业中对暂堵剂耐高温性能的要求，简化解堵的工艺流程，以多聚甲醛和聚醚胺为原料， 利用无机盐的催化作用在高温下形成聚合物凝胶。研究了温度和组成对该聚合物凝胶成胶时间的影响，并通过 机械压缩实验和岩心驱替实验评价了聚合物凝胶的力学性能和封堵性能。结果表明，胶液中溶剂、多聚甲醛和 聚醚胺含量对成胶时间的影响较小，而温度和无机盐的影响较大。随着温度由100 ℃增加至160 ℃，聚合物凝 胶的成胶时间逐渐减少。当温度为140 ℃时，加入氯化锌、氯化钙、硫酸铁铵和氯化镉的聚合物凝胶的成胶时间 分别为65、50、25、20 min。在3.57 MPa下，该凝胶经循环机械施压后仍具有优异的机械强度。在140 ℃老化10 d后，凝胶稳定性良好，机械强度保持率大于95%。岩心驱替实验表明，此凝胶封堵压力高达5.08 MPa，突破压力 梯度达84.00 MPa/m，具有优异的封堵性能。使用质量分数为10%的盐酸可在4 h内破胶，破胶后岩心渗透率大 于初始渗透率。破胶液的临界胶束浓度ccmc为200 mg/L，γcmc为29.80 mN/m，具有较好的表面活性，易于返排也可 提高洗油效率。所制备的耐高温暂堵剂与常规暂堵剂相比在暂堵性能上具有较大优势，通过与酸化或酸洗等工 艺结合可达到破胶的目的，此外破胶液具有的高表面活性有助于其他采油工艺。

In order to meet the requirement of high-temperature resistance of temporary plugging agent in high temperature-reservoir operation and simplify the process flow of unblocking，under the catalytic effect of inorganic salts，polymer gels was prepared at high temperatures using paraformaldehyde and polyether amines as main raw materials. The effects of temperature and components on the formation time of the polymer gels were investigated，and the mechanical properties and temporary plugging performance of the polymer gels were evaluated by mechanical compression experiments and core displacement experiments. The results showed that there was a slight influence of solvent，paraformaldehyde，and polyetheramine content on the formation time of polymer gels，while the temperature and inorganic salts had a significant effect. The formation time of polymer gels decreased as the temperature increased from 100 ℃ to 160 ℃. At the temperature of 140 ℃，the formation time was 65，50， 25，20 min，respectively，when the inorganic salts was ZnCl2，CaCl2，NH4Fe（SO4）2·12H2O and CdCl2·2.5H2O，respectively. Mechanical compression experiments showed that the gels had excellent mechanical strength after cyclic mechanical application under a pressure of 3.57 MPa，the stability of the gells was excellent after aging for 10 days at the temperature of 140 ℃，and the strength retention rate was more than 95% . The core displacement experiment showed that the gels had excellent blocking performance with a temporary blocking pressure of 5.08 MPa and a breakthrough pressure gradient of 84.00 MPa/m. The gels could be broken within 4 h using 10% hydrochloric acid，and the core permeability recovery rate was higher than 100 % after breaking the gel. The ccmc of the gel breaking liquid was 200 mg/L，and γcmc was 29.80 mN/m，which had good surface activity and could improve the oil-washing efficiency. The obtained high-temperature resistant plugging agent had a significant advantage over conventional plugging agents in terms of plugging performance，and its efficient surface activity of the gel breaking liquid was helpful to other oil recovery processes.

10.19346/j.cnki.1000-4092.2023.03.010