新型耐温耐盐气润湿岩心的制备及性能评价

Preparation and Evaluation of Novel Gas-wetting Alternation Agent with Temperature Resistance and Salt Tolerance

王彦玲 金家锋 蒋官澄

WANG Yanling JIN Jiafeng JIANG Guancheng

为了解非离子型气湿反转剂在改变砂岩表面润湿性方面的作用效果，获得气润湿性良好的砂岩地层，提高凝析气藏的生产能力，分别采用接触角法和Owens二液法考察了非离子型表面活性剂处理前后砂岩岩心的气润湿程度和表面自由能，研究了无机盐、温度和pH值对气润湿性的影响及气润湿反转的有效期。结果表明，质量 分数为0.3%的非离子型氟碳表面活性剂（FG24）可将岩心表面的润湿性由液润湿性反转为强气润湿性，水相和油相在岩心表面的接触角由处理前的36.0°和0°分别增至141.3°和108.0°，且岩心的表面自由能由71.0 mN/m急剧降至3.29 mN/m。在pH值为1～10、无机盐溶液质量浓度为100 g/L、温度140℃范围内，油水相在岩心表面的接触角均大于90°；岩心可在60 d 内保持强气润湿性。FG24 可将岩心表面反转为強气湿性，并具有良好的耐盐性和耐温性。图4 表1 参14

In order to investigate the effect of non-ionic gas-wetting agent on the wettability of cores，obtain gas-wetting sandstone core and enhance the gas-condensate recovery，gas-wetting and surface free energy of cores before and after treatment were measured using contact-angle measurement and Owens two-liquid method respectively. Meanwhile，the effect of inorganic salt，temperature and pH value on the gas-wetting core and the lasting time of gas-wetting were studied. The results showed that the wettability of core was altered from liquid-wetting into gas-wetting by 0.3% non-ionic fluorocarbon surfactant（FG24）treatment， the contact-angle of water and decane on the surface of core increased from 36.0° and 0° to 141.3° and 108.0°，respectively，and the surface free energy of core sharply decreased from 71.0 mN/m to 3.29 mN/m. The treated core could keep preferential gas-wetting on the condition of pH=1—10，100 g/L inorganic salt and 140℃. The contact angle of water and decane on the surface of core was larger than 90°，and FG24 had a long term validity about 60 days. FG24 could alter the rock surface to strong gas-wetting and show excellent heat resistance and salt tolerance.

10.19346/j.cnki.1000-4092.2016.06.033