Unlocking Environmental Solutions: Case Study of Acid Gas Storage in a Partially Depleted Hydrocarbon Reservoir

Acid gas storage stands as a well-established technology that mitigates the adverse release of acidic gases, such as hydrogen sulphide (H2S) and carbon dioxide (CO2), into the atmosphere. This approach involves the underground injection of these acidic compounds to store them safely and permanently in geological reservoirs. In this work, we investigate and confirm the technical feasibility of using acid gas storage in a partially depleted gas condensate reservoir in the Middle East Region. The studied reservoir produces sour gas with approximate concentrations of 3% H2S and 5% CO2. Several acid gas handling alternatives were evaluated, and one partially depleted gas condensate reservoir was identified as a suitable storage site. The selected storage complex, theoretically satisfy all key site selection criteria such as: containment existence or seal capacity, enough static storage capacity for the acid gas volumes expected to be generated, good depth range (1000–2500 m), sufficient matrix permeability to assure injectivity and reduced risk of leaks through wells due to few (8) well penetrations. Ongoing de-risking efforts aim to mature and optimize the acid gas storage project as the preferred option for acid gas handling in this area.