Experimental investigation of wellbore integrity during geological carbon sequestration: Thermal- and pressure-cycling experiments

The long-term safety and integrity of CO2 storage in geological formations requires understanding of the interactions along the injection well between CO2 and casing, cement, and rock, which may lead to potential leakage pathways and compromise the storage security. The current knowledge on the large scale evaluation of casing-cement or cement-rock composites behavior under reservoir pressure and temperature (P the higher the effective pressure, the lower the permeability. Temperature cycling effect on the composite casing-cement was also investigated and the results showed that at subzero temperatures freezing of water in the pore space of cement caused no hydraulic conductivity (no flow of CO2), moreover, no significant change in the original permeability was observed after thawing.