Abstract: The invention provides a circulating fluidized bed apparatus comprising a housing and a pair of spaced partitions located within the interior of the housing. The partitions are spaced from each other to define a draught zone therebetween having a lower inlet and an upper outlet. Separate fluid feed arrangements are provided for feeding separate fluidizing fluids into the housing for fluidizing particulate material in the draught zone and for fluidizing particulate material outside the draught zone. Above the draught zone the housing has a fluid outlet arrangement for fluidizing fluid from the draught zone, and a fluid outlet arrangement for fluidizing fluid from the housing outside the draught zone.