Criteria and workflow for selecting depleted hydrocarbon reservoirs for carbon storage

Abstract

Carbon capture and sequestration (CCS) is playing a role in mitigating carbon emissions and that role is expected to grow dramatically with time. Clustering CO₂ sources and sinks through hubs is one way to achieve large-scale deployment of CCS and widespread decarbonization of the energy sector. A key element to the success of hub projects is finding a suitable sequestration site to store these combined emissions. In this study, a quantitative, criteria-driven methodology was developed to assess the potential suitability of depleted oil and gas reservoirs for carbon storage. The methodology utilizes a three-stage process that screens, ranks, and characterizes potential sites based on three categories: (1) capacity and injectivity optimization, (2) retention and geomechanical risk minimization, and (3) siting and economic constraints. Many potential sites are assessable using this methodology until an optimal depleted reservoir, or geographically adjacent set of reservoirs, is identified. The framework is designed to provide insights into the suitability of depleted reservoirs in a variety of different geological environments as well as to be adaptable to a project’s specifications. Specifically, the criteria-driven workflow was applied to fields in the Gulf of Mexico and screened 1,317 fields to identify 10 clusters of 31 fields for further assessment and then ranked those fields and clusters to identify the most suitable sites for secure storage.