Abstract: A method and apparatus for cleaning hot gases produced during a coal gasification process in a reactor, wherein the hot gases leaving the reactor are cooled in a plurality of cooling stages to a relatively low temperature. In accordance with this invention, a particulated solid is added to the hot gases and circulated through at least one of the cooling stages. The particulated solid may be a material which decomposes in the hot gases to liberate carbon dioxide or it may be inert.The apparatus of the invention makes use of a heat exchanger which functions as a radiant cooler and also as a mixer for the gases and solids, the heat exchanger being connected directly to the gasification reactor at the exhaust gas side thereof. The heat exchanger is followed by at least one downstream, multi-stage cyclone fluidized bed heat exchanger which also is provided with an indirect heat exchange capability.

Abstract: A filter structure including a circular housing and annularly disposed individual filter chambers each containing a layer of bulk filter material with a centrally located waste channel having openings leading from each of the chambers above the surface of the filter material, an outer jet for each chamber for directing a cleaning agent along the top of the filter material, a separate supply for fresh filter material at the top of each chamber, clean gas discharge conduits located below the individual filter chambers and a cleaning gas jet connected to each of the clean gas discharge conduits leading downwardly from each of the chambers.