PRECALCINATION METHOD WITH PRODUCTION OF PURE OR EASILY PURIFIED CO2 ORIGINATING FROM THE DECOMPOSITION OF CARBONATES

摘要

The method proposed consists in superheating a stream of calcined material (normally CaO) to a temperature above the calcination temperature and circulating this superheated stream of calcined material to the calciner, where the solids release heat. This calciner is also supplied with the stream of material to be calcined (normally preheated CaCO 3 ), so that the heat released by the hot CaO stream gives rise to decomposition of the supplied CaCO 3 to CO 2 and CaO. A portion of the CaO leaving the calciner is the calcined product and the remainder is recycled for superheating in a combustor. The CO 2 generated in the calcining stage is obtained in pure or easily purified form and is thereof capable of being used or stored