Regular Article

Numerical simulation study of CO₂ storage capacity in Deep Saline aquifers

¹ Energy College, Chengdu University of Technology, 1, Dongsan Road, Erxian Bridge, Chenghua district, Chengdu, Sichuan, PR China
² Geological Resources and Geological Engineering Postdoctoral Research Station, Chengdu University of Technology, 1, Dongsan Road, Erxian Bridge, Chenghua district, Chengdu, Sichuan, PR China
³ State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, 8, Xindu Avenue, Xindu District, Chengdu, Sichuan, PR China

^* Corresponding author: zhangdongxu1992@outlook.com

Received: 19 May 2023
Accepted: 23 January 2024

Abstract

The storage of supercritical CO₂ in deep saline aquifers is essential for reducing carbon emissions, and the selection of an appropriate reservoir is a primary consideration for carbon sequestration. To investigate the impact of reservoir physical properties on the CO₂ storage capacity of saline aquifers, this study establishes a numerical simulation model of CO₂ storage in deep saline aquifers and utilizes the MRST toolbox to solve it by the finite volume method. The research thoroughly analyzes the influence of reservoir physical properties on the CO₂ migration process and CO₂ storage capacity of the saline aquifer layer. The results show that prolonged CO₂ injection involves a process of initially suppressing pressure and subsequently slowly diffusing it to the surroundings. Furthermore, the physical properties of the reservoir and the reservoir pressure significantly influence CO₂ burial in deep saline aquifers. Higher reservoir permeability and deeper burial depth result in enhanced CO₂ storage and faster CO₂ plume migration. However, the porosity and temperature of the reservoir have a negligible impact on CO₂ storage. Our research work provides a precise understanding of selecting suitable layers for CO₂ storage in deep saline aquifers, offering strong support for early predictions of carbon capture, utilization, and storage (CCUS).