This work package aims at developing and testing technologies to safely abandon CO2 injection wells, and to assess their performance in the long-term, well beyond the abandonment stage of a storage site.
The following items are essential:
- Assess the quality of both the cement sheath and the casing of the injection well or any well located in the storage complex with respect to CO2 storage.
- Matching the well’s historical behaviour and predictive models methodology to evaluate well integrity during closure and post-closure phases and to design effective abandonment procedures.
- Abandonment experiments (e.g. at Ketzin) with monitoring well and plug integrity under injection pressure and after cessation of injection.
The research will consider current practices and regulatory framework for site abandonment and will combine laboratory experiments, numerical modelling and field work to develop and implement robust techniques to abandon wells and to monitor their integrity. A few wells representative of plausible scenarios when storing CO2 in a saline underground aquifer or in a depleted oil or gas reservoir is used for the validation of the techniques implemented. The outcome will also contribute to best practice guidelines and recommendations for well abandonment in future and possibly also for CO2 injection well design.
SEM (BSE) analysis of the reservoir rock for porosity and permeability. Pore spaces are coloured in blue (source: GFZ).