A Novel Approach for Carbon Capture & Sequestration Pilot Study in the Western Desert of Egypt

Abstract

Egypt, as the host for the previous UN COP27 in 2022, has committed to emissions reductions in support of limiting global warming. Carbon capture and storage (CCS) offers the potential to significantly reduce point source CO2 emissions in the country. Accordingly, the Egyptian operator BAPETCO, along with partners Cheiron and Capricorn, is exploring the potential for carbon capture and storage to sequester more than 350,000 metric tons of CO2 per annum.at two fields in Egypt’s Western Desert. Storage candidates comprise 20 stacked geological formations starting from Apolonia till Lower Safa, The objective of this paper is to present the novel methodology implemented to screen technically feasible and economically advantageous subsurface storage sites. The applied approach is divided into three phases.1. The first phase is site screening, ranking, and selection to identify the best possible sites for CO2 storage. Through detailed geological characterization and modeling of all potential reservoirs within the two fields, specific sites are selected and ranked based on a scientific scorecard that is developed based on extensive experimental simulations worldwide.2. The sites with the highest rank pass to phase 2, the feasibility study. In this phase, selected reservoirs are reviewed in detail to quantify the reservoir capacity, optimize injection scenarios, confirm the required well count, and propose injection points. The study will forecast the evolution of the CO2 plume over time, by modeling the injected supercritical CO2 plume movement within the formations while honoring advanced trapping mechanisms such as CO2 trapping due to residual trapping, dissolution in saline water, and mineralization. Then, dynamic reservoir simulation models are fully coupled to 3D geomechanics models to study the impact of the injection on the well integrity, cap rock integrity as well as fault reactivation and integrity.3. Once the subsurface sites successfully pass the feasibility study, risk assessment, and mitigation, phase 3 is implemented to propose reasonable and economical surface facility configuration and pipelining scenarios that fit the subsurface sites’ requirements in terms of the number of wells and distance between them, depth of injection, required wellhead pressure, and proximity from CO2 source of emission. the followed scientific approach resulted in concluding four feasible sites in the two fields to be deployed for a long-term and safe sequestration of more than 350,000 metric tons of CO2 per annum. In this case study, we present the details of this integrated approach to account for the complex surface and subsurface nature of the western desert of Egypt during other CCS studies in similar environments.