Potential for Permanent CO2 Geological Storage, an Onshore Abu Dhabi Large Scale Assessment

Abstract

AbstractCCS technologies are well established, many ongoing projects have proven to be safe and reliable. Saline aquifers can be leading CO2 permanent storage candidates. A comprehensive multi-discipline study was carried out looking at the potential for CO2 sequestration in deep saline aquifer formations onshore Abu Dhabi. The area of interest is large in scale (regional scale) and consists of multi saline aquifer formations. The study has the added complexity that the same saline aquifer formations may be shared with near-by hydrocarbon exploration and production activities. The objectives were to analyze available geological data, define screening, selection and ranking criteria, identify key constraining factors especially concerning CO2 containment assurance, and arrive at regional storage capacity range estimates.Considerable amount of geological data and studies are available, which can assist with regional Onshore Abu Dhabi saline aquifer formation geological characterization for CO2 storage assessment. The characterization synthesis forms the study basis. A benchmarking was conducted, published screening and selection processes were reviewed. By incorporating key formation geological characteristics, a list of potential formation candidates were generated.A new set of guidelines for large scale (regional saline aquifer) CO2 storage candidate screening is proposed, based on the earlier guidelines set out in DOE/NETL-2017/1844 (2017). Detailed considerations and evaluation during the screening process are presented. A new candidate ranking and selection matrix is proposed. Highest ranked candidates from the ranking and selection exercise were identified. Dedicated regional scale 3D saline aquifer formations static model was constructed, and compositional simulation model developed for CO2 sequestration capturing the key CO2 sequestration processes/mechanisms. Storage capacity estimates were obtained from the dynamic model - the results published separately.Large scale (regional saline aquifer) CO2 storage candidate screening, ranking and selection is a challenging process with many inherent uncertainties. It carries critical importance as the results and recommendations would pave the way for further feasibility or detailed studies and the definition of de- risking activities. It requires multi-discipline input and forms the corner stone for large CO2 storage project development. The study approach, new candidate screening guidelines, ranking and selection matrix may offer discernment for Operators planning similar assessments.