可提高渗吸效率的阴非离子型表面活性剂制备与性能评价

Preparation and Performance Evaluation of an Anionic-nonionic Surfactant with High Imbibition Efficiency

范华波 薛小佳 刘 锦 郭 钢 李 楷 吴 江

FAN Huabo XUE Xiaojia LIU Jin GUO Gang LI Kai WU Jiang

表面活性剂在微裂缝细小吼道发生渗吸效应可以提高单井产量。以烷基醇聚氧乙烯醚和马来酸酐为原料合成了阴非离子型表面活性剂 AN211，用核磁共振仪表征了产物结构，研究了 AN211的临界胶束浓度、油水界面张力、润湿性和渗吸效率等性能。结果表明，AN211的临界胶束浓度为 0.052 g/L；AN211溶液的界面张力随浓度增加而降低，0.3% AN211溶液的界面张力为 3.37mN/m；AN211改变岩心润湿性能较强，润湿时间较短，通过降低岩心表面 Zeta电位改变其润湿性，实现润湿反转；AN211有效剥离了岩心表面的油性吸附物，其水溶液在岩心中的渗吸效率可达 48%，渗吸效率提高，其渗吸性能受矿化度影响小，水质适用范围广。AN211性能优于两性表面活性剂椰油酰胺丙基羟基磺基甜菜碱、阳离子型表面活性剂十六烷基三甲基氯化铵和驱油剂 QY-1，可用于非常规油气藏储层驱油。图 19表 4参 20

The effect of surfactant on micro-cracks and fine tunnels could increase the yield of single well. The anionic-nonionic surfactant AN211 was synthesized by alkyl alcohol polyoxyethylene ether and maleic anhydride. The structure of the product was characterized by NMR. The critical micelle concentration，oil-water interfacial tension，wettability，imbibition efficiency and other properties of AN211 were studied. The results showed that the critical micelle concentration of AN211 was 0.052 g/L. The interfacial tension of AN211 solution decreased with the increase of concentration. The interfacial tension of 0.3% AN211 solution was 3.37 mN/m. AN211 had strong ability to change core wettability and short wettability time. By reducing Zeta potential on core surface，AN211 could change core wettability and achieve wettability reversal. AN211 effectively stripped oily adsorbate on core surface，and the imbibition efficiency improved with 48%. Its permeability was less affected by the degree of mineralization，and its application of water scope was wide. The performance of AN211 was better than that of amphoteric surfactant coconut oil amides acrylamide hydroxy sulfonyl betaine，cationic surfactant cetyltrimethyl ammonium chloride and oil displacement agent QY-1，which could be used for oil displacement of unconventional oil and gas reservoir.