Performance and enhanced oil recovery efficiency of an acid-resistant polymer microspheres of anti-CO2 channeling in low-permeability reservoirs

• DOI: 10.1016/j.petsci.2024.02.002
• Publication Date: 2024-02-04T01:50:12Z
• Authors: Hai-Zhuang Jiang; Hong-Bin Yang; Ruo-Sheng Pan; Zhen-Yu Ren; Wan-Li Kang; Jun-Yi Zhang; Shi-Long Pan; Bauyrzhan Sarsenb...

CO2 flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs. However, micro-fractures are developed reservoirs, which essential flow channels but can also cause severe gas channeling problems. Therefore, anti-gas necessary measure to improve the effect of flooding. The kind refers plugging fractures deep formation prevent channeling, different from wellbore leakage. Polymer microspheres have characteristics controllable plugging, achieve profile control fractured In acidic environments with supercritical CO2, traditional polymer poor expandability and properties. Based on previous work, systematic evaluation expansion performance, dispersion rheological properties, stability, migration, anti-CO2 ability novel acid-resistant microsphere (DCNPM-A) was carried out under CQ oilfield conditions (salinity 85,000 mg/L, 80 °C, pH = 3). results show that DCNPM-A had better performance than microsphere, swelling rate 13.5. concentration 0.1%–0.5% advantages low viscosity, high good injectability permeability core. environment showed excellent stability could maintain strength over 60 d less loss. core experiments, exhibited delayed effectively plug formations. With 95%, subsequent reach 21.03%. experimental provide theoretical basis