稠油乳化驱油机理及室内效果评价

渤海L油田属于稠油油藏，存在水驱开发程度较低的问题。为了改善油水差异的问题，开展了稠油乳化剂与储层岩石润湿能力、原油之间乳化能力、界面张力和降黏效果实验及机理研究。结果表明，稠油乳化剂一方面可以使亲油岩石转变为亲水岩石，另一方面降低亲水岩石的亲水性，有利于将原油与岩石分离，达到提高洗油效率的目的。当"油:水"低于"4:6"时，稠油乳化剂溶液与原油可形成W/O/W型乳状液，大幅度降低稠油黏度，达到改善稠油储层内流动性和扩大宏观波及体积的目的。稠油乳化剂与原油在多孔介质内接触并发生乳化作用，乳状液通过吼道时存在"贾敏效应"，致使局部渗流阻力增加和微观波及效果提高。

Emulsifying Displacement Mechanism of Heavy Oil and Its Laboratory Effect Evaluation

Bohai L oilfield belongs to heavy oil reservoir,which has a problem of low water drive development.In order to improve the difference between oil and water,experiments and mechanism of wetting ability between heavy oil emulsifier and reservoir rock,emulsifying ability between heavy oil emulsifier and crude oil,interfacial tension and viscosity reduction effect were carried out.The results show that emulsifier can transform lipophilic rock into hydrophilic rock,and it can reduce the hydrophilicity of hydrophilic rock,which is beneficial to stripping crude oil from rock surface and improving oil washing efficiency.When the rate of oil and water is lower than“4:6”,the emulsifier can be mixed with crude oil to form W/O/W type emulsion,and therefore it can greatly reduce the viscosity of heavy oil and achieve the purpose of improving the fluidity of heavy oil reservoirs and expanding the macroscopic sweep volume.The contact of emulsifier with crude oil in porous media can result in emulsification.The"Jiamin effect"takes place when the emulsion passes through the roar,which results in increased local seepage resistance and enhanced micro-ripple effect.