نوع مقاله : مقاله پژوهشی
نویسندگان
1 پژوهشگاه صنعت نفت
2 پژوهشگاهصنعت نفت
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Low salinity water injection is a usable method in enhanced oil recovery, garnering attention due to its low risk and economic viability. The impact of low salinity water on reservoir rocks, especially carbonates, remains the subject of extensive research due to the complex interactions between rock-fluid, and the fluid-fluid interactions. Previous studies have indicated that the presence of anhydrite minerals in a carbonate rock enhances oil production, permeability, and plays a positive role in oil recovery. In this study, various experiments, including zeta potential, interfacial tension, core flooding, and effluent water ion analysis, were conducted to better understand the interaction between rocks containing anhydrite and dolomite and the fluid, which includes injected sample waters with different salinities. The results suggest that reducing salinity and diluting injection water weaken the ionic strength and electrical double layers around particles, leading to a decrease in zeta potential. The rock-fluid interaction results in the dissolution of minerals such as anhydrite and dolomite associated with calcium and magnesium ions, resulting in a reduction in the rock surface electrical charge. Simultaneously, the reaction causes the precipitation of other ions. Low salinity water, diluted by both four and twenty times, was injected into pure calcite rocks containing anhydrite in both secondary and tertiary methods. According to the results, injection of four times diluted water after high salinity water injection in two rocks increased oil recovery. Elemental analysis and effluent water analysis from core flooding experiments revealed multiple ion exchange and mineral solubility as mechanisms altering wettability.
کلیدواژهها [English]
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