Near InjectioN Optimization (NINO) for Carbon Capture and Storage in Depleted Gas Reservoirs

This paper explores the feasibility of CO2 storage in depleted gas reservoirs, focusing on geomechanical risks associated with CO2 injection. Using Shell’s proprietary Near InjectioN Optimization tool, the study simulates the impact of injecting dense phase CO2 into an ultra-depleted gas field in the North Sea, and highlights the significant cooling effects and potential risks such as thermal fracturing and reduced injectivity. The results show that while extreme cooling reduces effective horizontal stress, fracturing conditions are not reached. Additionally, the caprock’s thickness ensures containment integrity. The findings highlight the importance of detailed geomechanical modeling to manage risks and optimize CO2 storage strategies effectively.