A process for decarbonation of particles of raw meal, to be burnt in a clinkering kiln at a cement plant, the process includes: a) decarbonation of particles of raw meal, in a fluidised bed heat exchanger, the particles being suspended in a rising carrier gas including carbon dioxide, the fluidised bed heat exchanger having a solid heat carrier circulating counter-current relative to the carrier gas, to provide an effluent gas including carbon dioxide and decarbonated raw meal; b) separating the effluent gas and the decarbonated raw meal c) separating the effluent gas into a first and second part; cooling the first part of the effluent gas and recycling to provide carrier gas, d) isolating the second part of effluent gas e) recovering and re-heating the heat carrier and recirculating to step (a).