Review of relevant trapping mechanisms based on site portfolio

 

This deliverable describes the chemical/physical background for the mechanisms for long-term stabilisation and immobilisation of CO₂. Based on this it is suggested how to evaluate the quantitative contribution from each mechanism to the trapping over time. The suite of mechanisms is also termed “SRDM” for Structural and stratigraphic trapping, Residual trapping, Dissolution in the brine, and Mineral trapping by geochemical fluid/mineral reactions and precipitation of minerals.
The quantitative contribution of each of these trapping mechanisms will be site-dependent, as the combination of the injection strategy, geological architecture and the migration pattern at later stages of stabilisation will determine their efficiency in immobilising parts of the CO₂ plume. This is illustrated by case studies from different storage sites.