石油科学通报2025，Vol.10Issue(2)：206-218,13.DOI:10.3969/j.issn.2096-1693.2025.03.007
碳酸盐岩油藏低矿化度水驱润湿调控提高采收率作用机理
Mechanism of enhanced oil recovery by wettability control-based low salinity water flooding in carbonate reservoir
摘要
Abstract
Low salinity water flooding is a new technology for enhancing oil recovery by adjusting the ion composition or con-centration of injected water.However,the applicable reservoir conditions and enhanced oil recovery mechanism of low salinity water flooding have not yet reached a consensus.In this paper,a series of laboratory experiments of wettability control-based low salinity flooding are carried out with plunger rock samples from marine carbonate reservoirs in the Middle East as the research object.Based on the theory of Derjaguin-Landau-Verwey-Overbeek theory(DLVO),an interfacial reaction model of a typical crude oil/brine/rock system is established,and the contact angle and total separation pressure are calculated simultaneously with the augmented Young-Laplace formula.The reliability of the model is verified by the literature experimental data,and the effects of ion concentration and ion type on the separation pressure curve and contact angle are clarified.The results show that in low salinity environments,the pore surface of carbonate rock is more water-wet under the action of fluid flushing,the oil displacement efficiency is higher,and the low salinity water improves the crude oil recovery by 3.2%;under the assumption of constant charge,the mathematical model established based on the DLVO theory for the crude oil/brine/rock system can accurately predict the change of contact angle;compared with the ion concentration,ion type has a greater impact on separation pressure and contact angle.Among divalent ions,Mg2+ions exhibit a more pronounced influence on wettability control compared to Ca2+ions.When the water film thickness is minimal,van der Waals force is the main force affecting the separation pressure.As the thickness of water film increases,the electric double layer force gradually becomes the main force.This study contributes to a deeper understanding of the wettability control mechanism of low salinity water flooding for enhanced oil recovery.关键词
低矿化度水驱/分离压力/扩展DLVO理论/润湿调控/提高采收率Key words
low salinity water flooding/disjoining pressure/extended DLVO theory/wettability control/enhanced oil recovery分类
能源科技引用本文复制引用
刘芳洲,王代刚,李勇,宋考平,魏晨吉,齐新轩..碳酸盐岩油藏低矿化度水驱润湿调控提高采收率作用机理[J].石油科学通报,2025,10(2):206-218,13.基金项目
国家自然科学基金面上项目(52174043)、中国石油科技创新基金(2022DQ02-0208)和国家自然科学基金企业联合基金项目(U22B6005)联合资助 （52174043）
