Specific system data

Wetting behaviour of water on a metal surface in a CO2 atmosphere Source: Eurotechnica

A series of specific system data was experimentally determined as a basis for the envisaged investigations of various individual processes within the CCS chain and as an input to the whole-chain model. This way, a more accurate assessment of potential impacts of impurities along the CCS chain was obtained. Finally, recommendations for acceptable tolerance ranges, e.g. of temperature and pressure variations, were deduced from these investigations.

Following system data were measured:

• chemical reactions of impurities in CO₂ streams triggered by mixing CO₂ streams of different compositions; variations of CO₂ stream composition along the CCS chain;
• phase behaviour, in particular outline of the multi-phase region and critical parameters, and the potential of hydrate formation;
• diffusion coefficients of various impurities in CO₂ at transport and storage conditions as well as diffusion of formation water in CO₂‐impurity mixtures of high density;
• acid formation and condensation from CO₂‐impurity mixtures at transport pressure and temperature conditions;
• interfacial properties between the CO₂ phase and the formation water; wetting of metallic/non-metallic materials and rock samples by CO₂-impurity mixtures;
• solubility and dissolution kinetics of CO₂ and impurities in formation water as well as potential consecutive reactions of dissolved impurities at pressure and temperature conditions relevant for geological storage;
• permeabililties of rock samples representative of potential storage reservoir rocks for different CO₂-impurity mixtures.

Experimental set-up for investigating dissolution and diffusion of CO2-rich fluids in formation water or rock samples using a magnetic suspension balance Source: Eurotechnica