Characterization and 4D imaging of near well CO2 flow in fractures and microannuli

Carbon Capture and Storage (CCS) is a promising technology to mitigate climate change. Ensuring long-term well integrity is crucial to prevent CO2 leakage, which could pose environmental and safety hazards. This project aims to develop a robust method for detecting CO2 leakage behind casing in the the wellbore. It will focus on imaging CO2 flow at various length scales, exploiting CO2's unique properties to enhance detectability. The project addresses critical challenges hindering CCS implementation: 1. Communicating CCS importance for global emission reduction: Effectively communicating CCS importance to policymakers, industry leaders, and the public is crucial for widespread acceptance and support. 2. Industry-academia collaboration to increase technology readiness level (TRL) of critical CCS technology: Collaboration is essential to accelerate CCS development and deployment. This project fosters a synergistic partnership between industry experts and academic researchers to advance the TRL of CO2 leakage detection methods. 3.Enabling well integrity diagnostics of active and abandoned wells: The project will develop methods for diagnosing the integrity of both active and abandoned wells, ensuring long-term CCS project safety. 4.Exploring particularities of CO2 flow and leakage pathways: Understanding CO2's unique properties will enable tailored detection methods that are highly sensitive to CO2 leakage. 5.Exploring how to detect CO2 leakage behind casing at different length scales: The project will investigate methods for detecting CO2 leakage at various distances from the leakage origin, from near-well leakage to larger-scale migration. The project's primary objective is to enhance CO2 storage safety by improving our understanding of CO2 flow behind casing. This encompasses understanding CO2 leakage mechanisms, potential remediation techniques, and developing cost-effective monitoring systems for early warning of well integrity loss.

The CHARISMA project will enhance CO2 storage safety by improving our knowledge on CO2 flow behind casing – including how it can be remediated and detected at various distances from the leakage origin. Experiments will focus on advanced experiments, brought to realistic field conditions through modelling. Behind-casing flow paths, such as micro-annuli and natural/drilling induced fractures will be induced and analysed, both experimentally and numerically, and in-situ flow experiments in the X-ray computed tomography machine will enable study of the fluid loss rate and its impact on surrounding materials. The success of remediation operations will be studied through the same procedure, which also enables studies of propagating secondary fractures (due to the high pressures during remediation fluid pumping). The final scope of the project is to address the detectability of CO2 flow at different scales, based on state-of-the-art instrumentation and methods in geophysics. The project will involve besides Norwegian partners SINTEF, NTNU and NGI, notable international partners from the US, the University of Pittsburgh, Colorado School of Mines and Lawrence Livermore National Laboratory. These will advise the local project team, taking advantage of their established expertise in designing remediation fluids and well integrity experimentation and modelling.