Durability and integrity of well and rock materials
Within WP5 data is acquired that underpins measures to de-risk subsurface hydrogen storage in porous reservoirs. Focus is on durability and integrity of well and reservoir rock materials subject to cyclic hydrogen injection and withdrawal at reservoir conditions. Current practices and existing experimental data for effects of hydrogen on well cement, reservoir rock and caprock are reviewed, and datasets are extended by a combination of batch reaction experiments and triaxial deformation experiments at reservoir pressure and temperature. Casing-cement-rock interface flow and mechanical properties are studied using a unique scaled-down well system that can be placed in both an autoclave and a triaxial cell. Microbial influenced corrosion is studied at high H2 partial pressures using bioreactors with combinations of materials, brine and microbial consortia. Implications for risks and mitigation measures regarding reservoir injectivity and productivity, integrity of geological seals, and zonal isolation of wells are assessed.