COALSWAD - a European project for the determination of the carbon dioxide storage capacity in coal

CO2 storage in appropriate geological reservoirs is considered as one possibility to decrease the amount of CO2 in the atmosphere. COALSWAD (www.coalswad.eu) deals with the storage of CO2 in coal seams. Our project is focussed on a comprehensive investigation of the adsorption behaviour of coal taking into consideration the influence of swelling behaviour. Coal samples of comparable rank but different source (Germany, Czech Republic and Spain) are examined. All samples are dried at 353 K for 36h under vacuum before the gravimetric adsorption measurements with He, CO2, CH4 and H2O at 313 K are started. These adsorption data are influenced by the swelling process occurring in coal, because possibly volume changes influence the buoyancy of the sample. Therefore it is essential to get detailed knowledge of swelling behaviour. By using SAXS- and NMR-techniques a detailed picture of structural changes in coal structure is gained. Results received show that with increasing coalification grade the degree of swelling decreases and the CO2 adsorption capacity increases