Drilling the World's First Fully Sequestered Co2 Injection Well: Challenges, Execution and Lesson Learned

According to the Intergovernmental Panel on Climate Change (IPCC) and the International Energy Agency (IEA), carbon capture and storage (CCS) is crucial for meeting climate change targets. CCS is a key part of the UAE's sustainability strategy and its commitment to achieving net-zero emissions. The field operator initiated a major CCS project focused on permanently storing CO2 in carbonate deep saline aquifers. Following a rigorous feasibility study, the first CO2 injection well was drilled. The aim was to gather the data essential for asset management, ensuring wellbore integrity in CO2-rich environments, and advancing real-time monitoring capabilities. The project employed several innovative techniques and methodologies to achieve its objectives. For the first time in the UAE, a permanent fiber optic cable was deployed behind a 7" casing to enable enhanced real-time monitoring. The project utilized CO2-resistant non-Portland cement globally for the first time to ensure the long-term integrity of the wellbore. Six coring runs were completed across intended cap rocks and target water reservoirs, and water samples were collected from the interest zone under expected loss formations. A TCP gun was used to perforate 600 feet of 9 5/8" casing in one run with a 100% firing success rate. Additionally, 3 ½" CRA tubing with dual fiber optic cables was run, and a deep-set surface-controlled subsurface safety valve (SSSV) was installed in the tubing. Custom wellhead modifications were made to accommodate fiber optic cable exits, and fit-for-purpose operational procedures were developed for the permanent deployment of fiber optics behind the casing. Feasibility studies, risk assessments, and de-risking strategies were integral to the project's execution. The project reached a significant milestone by achieving 100% data gathering, meeting the asset's requirements, and marking several groundbreaking achievements along the way. One notable accomplishment was the successful mini frac operation across hard cap rock RUS, a first-of-its-kind operation in the UAE. This operation validated the feasibility of this formation to act as a caprock, crucial for ensuring the safe injection and containment of CO2. Moreover, the project was executed with zero HSE (Health, Safety, and Environment) incidents.