乳化剂HC-5 的性能及驱油效果

Performance and Oil Displacement Effect of Emulsifier HC-5

任朝华 张先超 尤万里 罗跃 汪庐山 靳彦欣 冯茜 张光华 李俊国

REN Zhaohua ZHANG Xianchao YOUWanli LUO Yue WANG Lushan JIN Yanxin FENG Xi ZHAND Guanghua LI Junguo

针对国内老油田的开发现状，对设计的乳化剂配方体系进行了基本性能评价和乳化驱油效果研究，探讨了乳化驱油的可行性和驱油机理。研究结果表明，优选的乳化剂配方体系HC-5（氨基磺酸型两性活性剂20%，OP系列非离子表面活性剂8%，稳定剂0.8%，助溶剂2.5%，其余为水）具有良好的耐盐抗盐性能，在室温～85℃范围内、盐度超过120 g/L 的混合盐水中的溶解性良好；HC-5 能在高、中和低盐度的盐水中有效乳化原油，并具有良好的乳化稳定性；HC-5 乳化体系的乳状液类型与盐度和含水率有关，盐度增加时，发生W/O型乳状液向O/W型转变的临界含水率增大，矿化度为15350 mg/L、40650 mg/L 和120670 mg/L 的体系的临界含水率分别为48%、57%和68 %。室内模拟乳化驱油试验表明，乳化驱对于低渗透驱替介质有明显增压和调剖作用，波及系数增大，原油采收率提高；而对于较高渗透率的驱替介质，乳液的调剖机理和表面活性剂驱油机理共同作用实现了原油采收率的提高。图7 表2 参12

Aimed at the development status of aged oilfield in our country，some basic performances of the emulsifier formula systems were evaluated and their oil displacement efficiency was investigated，and the feasibility of the EOR experiment through emulsified oil and their mechanisms were discussed. The experimental results showed that the optimized emulsifier formula system HC-5，containing about 20% amino sulfonate amphoteric surfactant，8% OP seriers nonionic surfactant，0.8% stabilizer，2.5% cosolvent， and water as remainder， had excellent performances of salt tolerance and temperature resistance， and had fine dissolubility in mixed salt aqueous solution with over 120 g/L salinity over the entire range of room temperature to 85℃. The HC-5 could emulsify efficiently the oil in the aqueous solutions with high，middle，and low salinity，and the stability of the formed emulsion was excellent. The type of emulsion formed by HC-5 was dependent on the salinity and the water cut in the bulk system. The critical water content for the transformation from the W/O type to the O/W type emulsion may increase with increasing the salinity in bulk system，for example，the critical water cut in the bulk systems with the salinity of 15350 mg/L，40650 mg/L，and 120670 mg/L，respectively，was of 48%，57%，and 68%，respectively. The laboratory experiment of emulsified oil displacement showed that the increase of injection pressure and the profile control effect could be found obviously in the media with low permeability，and consequently the increase of sweep efficiency factor could enhance the oil recovery. As for the media with higher permeability，the mechanism of profile control from the emulsified effect and the oil-displacement mechanism from the decrease of interfacial tension by surfactant may together influence the enhancement of oil recovery.