A 1 m in diameter and 3.55 m tall fluidized bed riser internally with water tubes, which required six equilibrium stage of riser-sorber for capturing about 95% of CO2 emitted from a coal power plant, were designed to replace the multisingle risers. At the optimum operating condition, the temperature of the cooling tubes in the bottom, the middle and the top of the riser were kept constant values at 50, 40, and 30 degrees C, respectively. The hot water (57 degrees C) from lowest exchanger section can be used to preheat the spent sorbent for the regeneration in a downer. The rest of the heat for the regenertion is obtained from the stack gas (100-130 degrees C). This new concept promises to reduce the energy consumption for CO2 removal from flue gas. The only energy requirement is for pumping fluid and fluidizing particles in the bed. (C) 2017 American Institute of Chemical Engineers