Optimization of CO2 Injection Well Placement and Injection Rates Considering Aquifer Injectivity

In geological CO 2 storage, a constant injection rate is often required owing to the operational constraints of CO 2 capture and transport infrastructure.This study proposes a stepwise optimization framework to determine optimal injection well placement and a constant injection rate for an aquifer.First, a multilevel grid system was applied under maximum allowable injection pressure conditions to identify the optimal well location.Subsequently, the maximum constant injection rate satisfying the pressure constraint was determined through iterative numerical simulations.The proposed method was applied to high-and low-injectivity aquifer models representing contrasting permeability conditions, and the impact of an additional injection well on CO 2 storage capacity was evaluated.The results indicate that the proposed method effectively identifies optimal well locations and constant injection rates while satisfying pressure limits.Storage capacity increased by 6% in the high-injectivity model and by 56% in the low-injectivity model, demonstrating that optimal well number and placement are strongly dependent on aquifer injectivity.