乳化和界面张力特征对二元驱体系驱油效果的影响

Effect of Emulsifying Feature and Interfacial Tension Characteristic on Displacement Efficiency of Binary Compound Flooding System

王 雨 吴永花 王华鹏 张珍珠 张玉敏

WANG Yu WU Yonghua WANG Huapeng ZHANG Zhenzhu ZHANG Yumin

为深入认识二元驱油体系乳化能力和界面张力对驱油效果的影响规律，评估了7类乳化指数介于0~0.38之间、与原油界面张力在 10-3~10 mN/m之间的二元复合驱油体系（a：0.3% KPS + 0.1% HPAM；b：0.5%司盘/ 0.5%吐温+0.1% HPAM；c：0.3% ZS + 0.1% HPAM；d：0.3%YC；e：0.3% HPS + 0.1% HPAM；f：0.3% SP + 0.1%HPAM；g：0.3%ZS + 0.1%HPAM + 0.4%Na2CO3）的动态乳化特性、动态界面张力与驱油效果的内在关联性。乳化特征分为5种类型：不乳化（体系f）、乳化反转（体系e）、前程乳化（a）、后程乳化（体系d）、全程乳化（体系b、c和 g）；界面张力特性分为7种类型：“L”型（体系a）、“—”型（体系b）、“浅碟”型（体系c）、“G”型（体系d）、“V”型（体系e）、“＼”型（体系f）、“深碗”型（体系g）。岩心驱油实验表明：驱油剂的乳化能力愈强，则二次水驱后的采收率愈高。不乳化的“＼”型体系（体系f）、全程乳化的“浅碟”型体系（体系c）、后程乳化的“G”型体系（体系d），二次水驱采收率分别为0.36%、4.25%和0%，体现了乳化对流度控制和界面张力对毛细管数效应的交织影响。通过对比聚合物驱和二元驱后的岩心剖面发现，二元驱后岩心中残余油分布呈“白斑”状，归因于不合理的段塞配置，使界面张力和乳化作用不足以抵消流度失控对采收率影响所致。在二元复合驱技术研究中，应优选具有超低界面张力和全程乳化能力的驱油体系，并重视驱油过程中的流度控制。图8表2参16

In order to deeply understand the influence law of emulsifying ability and interfacial tension on oil displacement effect of binary oil displacement system，seven systems，including 0.3% KPS + 0.1% HPAM（a）0.5%Span/0.5%Twain+0.1% HPAM（b），0.3% ZS + 0.1% HPAM（c），0.3%YC（d），0.3% HPS + 0.1% HPAM（e），0.3% SP + 0.1% HPAM（f），0.3%ZS + 0.1%HPAM +0.4%Na2CO3（g），were selected for researching on the internal correlation between dynamic emulsification characteristics，dynamicinterfacial tension and oil displacement effect. Water-separating test and interfacial tension measurement showed that emulsification index was in range of 0 to 0.38，the interfacial tension was in range of 10-3—10 mN/m. The emulsification characteristics of thesesystem could be divided into five types：“non-emulsification”（system f），“emulsification reversal”（system e），“former-process emulsification”（system a），“rear-process emulsification”（system d）and“whole-process emulsification”（system b，c and g），interfacial tension peculiarity was divided into 7 types：“L”type（system a），“—”type（system b），“shallow dish”type（system c），“G”type（system d），“V”type（system e），“\”type（system f），“deep bowl”type（system g）. Core displacement test revealed that the stronger of emulsifying ability was，the higher recovery efficiency of the secondary water flooding had. For“\”system f with“non-emulsification”，“shallow dish”system c with“whole-process emulsion”and“G”system d with“rear-process emulsion”，the secondary water flooding recovery was 0.36%，4.25%，0%，respectively，that due to the interlaced action of the emulsify on mobility control and interfacial tension on capillary number effect. In addition，by compared the residual oil distribution after polymer and the binary compound flooding，uneven distribution of residual oil after binary flooding was found and "white spot" was prone to form because of unreasonable slug collocated，so the interfacial tension and the emulsification was not enough to offset the out of control mobility. Therefore，the displacement system with ultra-low interfacial tension and whole-process emulsion capacity should be preferred to and the fluidity control should be intensified in binary compound flooding technology

10.19346/j.cnki.1000-4092.2019.04.025