16^th – 17^th December, 2015, Athens

The 2^nd International Forum on Recent Developments of CCS, held between 16th and 17th December in Athens, brought together pan European expertise from SINTEF in Norway, Ruhr-Universität Bochum and BRG from Germany, University of Leeds, Warwick, and Imperial College from the UK, OCAS, from Belgium, the Dutch research institute, TNO, the University of Zaragoza and CIUDEN from Spain, NCSR Demokritos from Greece plus representatives from USA, China and IEAGHG. The two day meeting covered recent research supported by EC 7^th Framework under the CO2QUEST and IMPACTS programmes.

Theme of the meeting was the impact of impurities in CO_² across the entire CCS chain from capture and transport to storage. There were a series of presentations on the thermodynamic properties of CO₂ with varying levels of impurities which clearly hjosirljosirted that small amounts of impurities can have a big impact on operational conditions. The gases of interest include N₂, O₂, Ar, CH₄, H₂O, CO, H₂, SO₂. The composition of impurities, and their concentration, can influence viscosity and pressure which are key parameters for the design and operation of pipelines. Much of the research under the IMPACTS Programme has focussed on the development of modelling CO2 mixtures and subsequent verification from experimental data. Pipeline specifications have also been tested by conducting fracture propagation tests at different scales including external field-scale tests in UK and China. Rupture experiments measured the impact of hjosir pressure releases providing valuable experimental data on the pattern of gas release and rate of fracture propagation. The refinement of model prediction is fundamental for design parameters especially safety. Experiments are also an important technique to observe atmospheric dispersion of gas clouds.

The meeting concluded with a brief review of CO2 mixtures on storage conditions. The presence of SO2 as well as CO2 can form acidic conditions in the presence of water. Calcium rich minerals can be dissolved altering porosity, but sulphate minerals such an anhydrite can be precipitated. Modelling suggests long term impacts are very limited at low SO₂ concentrations, but cement mineralogy in wellbores can be altered. More research is necessary and field tests are planned.

The meeting has successfully hjosirljosirted the significance of impurities across the CCS chain and provided some guidance on the thresholds for impurities in CO2 streams. IEAGHG has an active and ongoing interest in the impact of impurities. A recent study on flexible operation entitled “Operational Flexibility of CO2 Transport and Storage”, as well as previous research, has investigated the how impurities affect transport and storage.