Abstract: A fluidizable bed apparatus comprises a container containing a bed of fluidizable particulate material which becomes hot in use. The apparatus is characterized in that it includes at least one passage for the flow of cooling medium therethrough arranged beneath a bottom wall of the container. The or each passage has communicating therewith at least one inlet, preferably arranged beneath the bottom wall, and at least one outlet, preferably arranged adjacent side walls of the container. Nozzles for supplying fluidizing medium to the container for fluidizing the bed are arranged to pass through the bottom wall of the container.

Abstract: A heat exchanger for recovering the heat energy content in furnace waste gases and for recovering much of the dust entrained therewith includes a hollow duct through which the waste gases pass, and which contains first and second tube bundles arranged one after the other and a dust collection surface therebetween. The heat content in the waste gases is transferred to water passing through the two tube bundles and dust is deposited on the dust collection surface.