Coal laboratory characterisation for CO2 geological storage

Geological storage of CO2 in unmineable coal seams could be a very interesting option in the sustainable management of coal basins. However, the various chemical and physical parameters that determine the success or failure of this type of operation need to be clarified. The CHARCO project aims at developing methods and analysis techniques in order to define the major parameters enabling optimal CO2 storage conditions. In this framework, 22 coals of different ranks were sampled in different locations and systematically characterized (coal ranks, macerals, porosities, CO2 and CH4 adsorption isotherms ...). The isotherms were modelled using the classical Langmuir formalism in order to obtain their adsorption capacities and their affinity for CO2. The high number of coals and parameters considered in our study allow a statistical treatment using Principal Component Analysis. The sorption capacity can not be easily correlated with any other single parameter. On the other hand, CO2 affinity is correlated with coal rank. (C) 2011 Published by Elsevier Ltd.