Falaha CCS Project - Pioneering Low Carbon Solutions with CO2 Sequestration in Deep Carbonate Saline Aquifers

Abstract

The ADNOC Falaha CCS Project, inaugurated in November 2023, marks a significant milestone in sustainability and supports the UAE's net-zero goals. This project is a world first, enabling the production of low-carbon products through CO2 sequestration in onshore deep carbonate saline aquifers. It is also the first full carbonate saline aquifer CCS project announced in the GCC Gulf region. The project has successfully captured and sequestered CO2. This paper aims to present the key results of the project, highlight technological innovations, and share initiatives undertaken to overcome challenges and fast-track project execution. A multi-disciplinary integrated approach, involving specialized external service providers, was adopted throughout the project stages. This approach aimed to ensure CO2 containment, cost optimization, and technological innovation. A comprehensive feasibility study was completed, benchmarking the project against international CCS projects. The de-risking program included data acquisition from offset wells and associated geo-mechanical and geo-chemical laboratory tests. For the appraisal well site location, new high-resolution 3D seismic data and offset wells data were used. Extensive risk analysis was performed, covering the full project life cycle. The well injection and Measurement, Monitoring, and Verification (MMV) plan was designed to meet both short-term and long-term technical (especially CO2 containment) and business requirements. The integrated project feasibility study identified several deep carbonate saline aquifer formations offering significant CO2 storage potential. High level study was carried out including surface facilities design and storage development plan. De-risking for CO2 containment assurance targeted open hole logs and core from offset wells, and associated comprehensive geo-mechanical and geo-chemical laboratory tests. The findings lead to the recommendation of drilling the first carbonate CO2 injection well, within the framework of a low carbon business development strategy. The Falaha CCS Project utilized high-resolution 3D seismic and offset well geological data to screen and select well locations. A 3D geo-mechanical study was conducted to aid in well injection design, ensuring the integrity of the cap-rock and minimizing the risks of far-field fault re-activation. Significant challenges in well design were addressed, such as the potential Joule-Thomson (J-T) cooling effects from CO2 injection. The CO2 injection design aimed to provide data for de-risking long-term injectivity and reduce overall storage capacity uncertainties. The MMV plan was designed to meet both short-term and long-term requirements. Innovative monitoring technologies, such as shallow soil tracers, CO2 in air laser detection, and Distributed Acoustic Sensing (DAS), Distributed Temperature Sensing (DTS), and Distributed Strain Sensing (DSS), were implemented. Baseline measurements, including baseline water injection, are described. CO2 injection commenced from Q3'2023. Injection performance exceeded prognoses. For this world's first onshore carbonate deep saline aquifer commercial CCS project, the work completed under the full-value-chain process is presented. This includes CCS feasibility, site selection, well and injection test design, MMV plan, risk assessment, and the low carbon business case. Key technical and design challenges are highlighted and addressed, along with technology innovations. Initial well results are shared. It is hoped that the multi-disciplinary integrated and commercially-driven approach can provide valuable insights for operators planning similar studies or projects.