Numerical Modelling of Carbon Dioxide Plume Dispersion in Sandstone Aquifer of Malay Basin

256.05 million tonnes of carbon dioxide (CO2) have been released into the atmosphere of Malaysia as of 2021. If no steps are done to limit Malaysia's CO2 emissions, it is projected that this scenario could go on for relatively many years to come. The feasibility of CO2 geological sequestration has been taken into consideration as a viable method of minimizing CO2 emission in Malaysia, considering the anticipated rise in energy demand for sustainable development in this nation. The long-term fate of the captured CO2 is, however, the primary concern of public and environment but it is not practical to do simulations in a lab or via experiments. In examining the movement of the CO2 plume after being injected into the sandstone aquifer, computer simulation is therefore more practical to utilize in this research. Malay Basin was ranked as the most potential basin for carbon sequestration in Malaysia because it fulfils most of the criteria. Therefore, by utilizing data from previous studies, 10 km2 of Malay Basin sandstone aquifer was simulated using COMSOL Multiphysics software in order to explore the pattern of CO2 dispersion in sandstone aquifer and to predict its migration radius in a given period. The second goal of this research is to determine a relationship between the rate of CO2 injection per 10 km2 and the velocity of CO2 plume flow in sandstone aquifer. Lastly, this study aims to estimate the saturation of CO2 per 10 km2 of the aquifer with various injection rates after a given time. Results from the numerical computation shows that CO2 injected into the Malay Basin migrates upward and laterally, with the plume pattern expanding over time and higher injection rates. On the other hand, the velocity of plume dispersion fluctuates and decreases with distance due to pressure gradients and dissolution of CO2 into the formation’s brine. Saturation of CO2 was also found to be the highest at the injection point and broadens with higher injection rates. This study's findings have practical implications for optimizing design, managing injection rates, assessing caprock integrity, implementing monitoring strategies, and conducting environmental impact assessments to ensure safe and effective carbon storage for long-term CO2 sequestration in Malay Basin. Given the size of Malaysia's geological CO2 sequestration industry, this research is seen as a wise investment from an economic standpoint. Politically speaking, the findings of this research provide policymakers and legislators with a suitable point of reference for implementing CO2 emission regulations in Malaysia.