Brine Production Strategies Mitigate Pressure Buildup in CCS Projects

Abstract This study investigated pressure management strategies for Carbon storage project by evaluating brine production in saline aquifers. As carbon capture and storage efforts expand, particularly in the Gulf Coast region, effective pressure mitigation remains a critical challenge for ensuring safe and efficient CO2 injection. We examined the impact of key design parameter, including CO2 injection rates, brine production rates, producer count, and reinjection approaches, on pressure buildup, storage capacity, and geomechanical stability. We conducted a series of reservoir simulations to analyze different configurations of injector and producer wells, varying production rates, and alternative brine handling methods. The results show that increasing brine production rates led to a significant reduction in pressure buildup compared to cases without brine production. Additionally, distributing production across multiple wells further enhanced pressure relief, with three producers achieving the lowest pressure buildup. CO2 injection rates also strongly influenced reservoir behavior, as higher injection rates led to larger plume extents and increased pressure, requiring careful optimization. Beyond pressure mitigation, this study explored the implications of reinjecting produced brine into upper aquifer layers instead of external disposal. While reinjection minimizes water disposal challenges, it reduces available pore space for CO2 storage, leading to pressure behavior similar to that of cases without brine production. Regulatory constraints on brine disposal highlight the need to balance operational feasibility with policy compliance. Additionally, geomechanical analysis showed that subsidence and uplift are minimal under the conditions studied, with minor displacement changes stabilizing post-injection. These findings provide a framework to optimize brine production strategies in CCS projects, and they demonstrate how injection and withdrawal configurations influence both storage efficiency and pressure management. By integrating reservoir simulation with geomechanical evaluation, this study offers valuable insights for designing safe and effective CCS operations, addressing key technical and regulatory challenges in large-scale carbon storage projects.