Method to increase CO2 capture efficiencies by carbonation and related carbonator

[EN] This invention discloses a method to increase the CO2 capture efficiency in a fluidized bed carbonator of CaO or Ca(OH)2 by exploiting the characteristics of a solid entrainment zone at the exit of the carbonator, where fine solids are in contact with the gas exiting the carbonator. The method being characterized by selectively cooling said entrainment zone to 500-600ºC by feeding the to the beginning of a solid entrainment zone part of the make-up flow of limestone at ambient temperature, by installing a heat exchanger section of a water/steam circuit, by spraying water or by feeding a flow of Ca(OH)2 powder at ambient temperature to capture the CO2 from the gas already depleted in CO2 that leaves the denser region of solids that is present at the bottom of the carbonator.