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BOrehole Monitoring Solutions for CO2storage wells

Several identified risks concerning CO2 storage are related to the risk of CO2 leakage in or near the well. In hydrocarbon fields, leaks have been recorded through the wellbore due to corrosion and mechanical failure of tubulars. Leaks also occur along the well path due to inadequate cementing of the casing, which might lead to cracks or debonding of the casing-cement-formation interfaces. Therefore, the well integrity is of great importance for the storage safety, and likewise, there is a large public focus on this subject.

Current integrity evaluation is mainly achieved through wireline logging, such as the cement bond log and the ultrasonic imager tool. While these give a good overview of the well’s status, they require the well to be shut in, are expensive to run and the data is collected within a short time frame. In the time between wireline runs (a few years) the state of the well is unknown. Current distributed fiber optic monitoring technologies focus on acoustic and temperature measurements, and not the mechanical soil-well interaction.

The project will create solutions for the monitoring that can be done inside and near onshore wells by investigating the operational needs for monitoring and describe existing technology, such as well head monitoring (pressure, temperature, flow) and petrophysical logging technology that could be improved or adapted for the continuous monitoring of the well.

The project will develop distributed fiber optics sensing to monitor deformation and temperature changes to a proof-of-concept stage for CO2 storage and evaluate if the technology is applicable for hydrogen storage wells.

  1. Define criteria for safe and environmentally sound well operation and operational needs for borehole monitoring.
  2. Establish an overview of existing methods and monitoring technology in use in a global perspective.
  3. Investigating how technology can be chosen and developed for CO2-monitoring in onshore wells and how well monitoring data can be used to improve various reservoir- and rock mechanical models.
  4. Find suitable solutions for existing well designs and test technology at a CO2 test-site.