稠油油藏Pickering微乳液黏土防膨机理实验探究*

Experiment Research on Mechanism of Anti-clay Swelling by Pickering Microemulsion in Heavy Oil Reservoir

郭明哲 刘慧卿 东晓虎

GUO Mingzhe，LIU Huiqing，DONG Xiaohu

针对水敏性稠油油藏，抑制黏土膨胀是有效进行热采的前提，然而注蒸汽后黏土防膨机理尚不十分明确， 因此提出用Pickering微乳液抑制黏土膨胀的方案，通过Fick定律与Langmuir吸附理论相结合，对Pickering微乳 液黏土防膨机理进行量化分析。用疏水纳米SiO2与月桂基三甲基溴化铵（DTAB）复配形成Pickering微乳液，通 过测定微乳液的表面张力和对膨润土的防膨率，对SiO2和DTAB的配比及微乳液的加量进行了优选，并按最佳 配方进行微乳液驱。机理量化分析结果表明采用表面吸附进行黏土防膨是可行的。纳米SiO2与DTAB质量比 为1∶2、微乳液加量为0.6%时的防膨效果最好。填砂管驱油实验中，微乳液最佳的注入量为0.2 PV。随着Picker ing微乳液注入量的增加，防膨效果增强，但后续水驱出口含水率上升速度也随之加快。对于渗透率较高的稠油 油藏抑制黏土膨胀应适当。

In view of water sensitive heavy oil reservoirs，inhibiting the expansion of clay is the premise for effective thermal recovery. However，the mechanism of anti-clay swelling is remaining unclear after steam injection. Therefore，a scheme of inhibiting clay swelling by using Pickering microemulsion was proposed. Through the combination of Fick’s law and Langmuir adsorption theory，the mechanism of anti-clay swelling by Pickering microemulsion was quantitatively analyzed. The Pickering microemulsion was prepared by mixing hydrophobic nano SiO2 with lauryl three methyl ammonium bromide（DTAB）. The surface tension of the microemulsion and the anti-bentonite swelling rate were determined. Then the mass ratio of SiO2 and DTAB，and the amount of microemulsion were optimized. Additionally，the microemulsion flooding was carried out according to the best formula. The quantitative analysis of mechanism showed that it was feasible to use surface adsorption to prevent clay swelling. The best anti-swelling effect was obtained when the mass ratio of nano SiO2 and DTAB was 1∶2 and the dosage of microemulsion was 0.6%. The best injection volume of microemulsion was 0.2 PV in sand pack flooding experiment. With increasing injection volume of Pickering microemulsion，the anti-swelling effect was enhanced，but the rate increment of water cut in outlet during sequent water flooding was also accelerated. Therefore，clay expansion should be inhibited properly in heavy oil reservoir with high permeability.

10.19346/j.cnki.1000-4092.2021.04.022