TY  - EJOU
AU  - Liu, Xiong 
AU  - Cui, Yueqi 
AU  - Ren, Yirui 
AU  - Peng, Lingxuan 
AU  - Cheng, Yuchan 
AU  - Du, Zhiyuan 
AU  - Chen, Yu 
AU  - Cao, Lishan 

TI  - Effect of Salinity on Imbibition-Based Oil Production
T2  - Fluid Dynamics \& Materials Processing

PY  - 2025
VL  - 21
IS  - 11
SN  - 1555-2578

AB  - This study explores the impact of salinity on fluid replacement during imbibition-driven oil recovery through a series of core self-imbibition experiments. By integrating key parameters such as interfacial tension, contact angle, and oil displacement efficiency, we systematically examine how variations in salinity level, ion type, and ion concentration affect the imbibition process. The results demonstrate that the salinity of the injected fluid exerts a strong influence on the rate and extent of oil recovery. Compared with high-salinity conditions, low-salinity injection, particularly below 5000 mg·L<sup>−1</sup>, induces pronounced fluctuations in the replacement rate, achieving the highest recovery at approximately 1000 mg·L<sup>−1</sup>. The interplay between interfacial tension and displacement efficiency is jointly governed by both ion type and concentration. Moreover, changes in ionic composition can alter rock wettability from oil-wet toward water-wet states, thereby enhancing imbibition efficiency. Among the tested ions, Mg<sup>2+</sup> and SO<sub>4</sub><sup>2−</sup> at low concentrations were found to be especially effective in promoting oil displacement.
KW  - Salinity; imbibition-enhanced oil recovery; ion concentration; ion composition; imbibition experiment

DO  - 10.32604/fdmp.2025.073775