Abstract: A fluidized bed combustion system and method in which a recycle heat exchanger is located adjacent the furnace section of the combustion system. A mixture of flue gases and entrained particulate materials from a fluidized bed in the furnace section are separated and the flue gases are passed to a heat recovery section and the separated particulate material to the fluidized bed in the recycle heat exchanger. A first chamber and plurality of additional chambers are formed in the recycle heat exchanger. A particulate material is supported in all of the additional chambers and air is introduced to each of the additional chambers to fluidize the material. The separated particulate material from the fluidized bed in the furnace section is introduced into one of the chambers and the chambers communicate to permit the material to flow between the chambers.

Abstract: A fluidized bed reactor in which a recycle heat exchanger is located adjacent the furnace of the reactor with each enclosing a fluidized bed and sharing a common wall including a plurality of water tubes. A mixture of flue gases and entrained particulate materials from the fluidized bed in the furnace are separated and the flue gases are passed to a heat recovery area and the separated particulate material to the fluidized bed in the recycle heat exchanger. The bed materials in the fluidized bed in the recycle heat exchanger are passed to the fluidized bed in the furnace. Steam is generated, superheated and reheated in the heat exchange surfaces, including water wall tubes, in the furnace, the recycle heat exchanger, and the heat recovery area.