季铵盐阳离子聚合物防膨剂对W/O乳状液稳定性的影响

Influence of Quaternary Ammonium Salt Cationic Polymer Anti-clay Swelling Agent on the Stability of Water-in-oil Emulsion

为揭示季铵盐阳离子聚合物防膨剂对热采稠油乳状液稳定性的影响规律,根据南堡35-2油田热采现场采出液特征,采用高温高压可视相态釜模拟配制油包水乳状液,研究了季铵盐阳离子聚合物防膨剂对油水界面张力、界面剪切黏度及乳状液表观黏度和破乳脱水率的影响。结果表明,随着防膨剂浓度的增大,油水间的界面张力降低,界面剪切黏度增大;防膨剂浓度一定时,随着剪切速率的增大,界面剪切黏度增大并最终趋于稳定。温度对乳状液体系的性能影响较大:防膨剂在55℃时几乎对原油的乳化不产生影响,防膨剂溶液与原油形成的乳状液不稳定;在乳化温度为100℃和150℃下形成的乳状液稳定性高,且其表观黏度随防膨剂浓度的增大而增大;防膨剂浓度一定时,随着乳化温度升高,乳状液的表观黏度明显增大,脱水率降低,150℃时含0.5%~10%防膨剂乳状液的脱水率均为0,稳定性良好。季铵盐阳离子聚合物防膨剂能降低油水间的界面能,提高界面膜强度,增加W/O型乳状液的稳定性。

In order to reveal the influence of anti-clay swelling agent of quaternary ammonium salt cationic polymer on the stability of heavy oil emulsion,basing on the factor of on-site produced liquid of cycle steam stimulation in NB35-2 oilfield,W/O emulsion was prepared by high-temperature high-pressure autoclave. The effects of anti-clay swelling agent on oil-water interfacial tension and interfacial shearing viscosity,apparent viscosity and emulsion dehydration rate were studied. The results indicated that oil-water interfacial tension decreased and interfacial shearing viscosity increased with increasing anti-clay swelling agent concentration. With the increase of shear rate,oil-water interfacial shearing viscosity increased and finally reached stability when anti-clay swelling agent concentration was constant. The temperature had great effect on the property of emulsion. The anti-clay swelling agent could not form a stable emulsion with crude oil at 55℃. The emulsion was stable and its apparent viscosity increased with increasing anti-clay swelling agent concentration when emulsification temperature was 100℃ and 150℃. Apparent viscosity of emulsion increased and emulsion dehydration rate decreased with increasing emulsifying temperature. When anti-clay swelling concentration was 0.5% —10%,the emulsion was stable and dehydration rate was 0 at 150℃. Anti-clay swelling agent of quaternary ammonium salt cationic polymer could reduce oil-water interfacial tension and increase interfacial film strength and the stability of W/O emulsion.