A method and apparatus are provided for separating particulate material from hot gas. Provisions are made for accommodating relative thermal expansion between a hot particular laden gas chamber, a particulate discharge chamber and a clean gas chamber. A main housing supports an interior subhousing supported from the top of the main housing while a further discharge chamber housing is supported from a lower part of the subhousing in such a manner that they are free to expand and contract independently of one another. Gas and particulate separators which are free from load bearing stresses are designed to receive the particulate laden gas and pass particulates to the particulate discharge chamber for bottom discharge and the gas to the clean gas chamber for discharge at the top of the main housing. Provisions are made for auxiliary discharge of particulates bypassing the separators at a bottom of the clean gas chamber. Relative expansion is provided for at the lower extremities of the main housing and subhousing and discharge chamber housing with gas sealing therebetween. Downward flow of the particulate laden hot gas past the separators is employed to drive the particulates in a direct line to minimize dissipating energy in peripheral or vortical flow.