Patent ID: 7553111

Claim:
An apparatus for conveying high temperature finely divided dry material comprising (a) an enclosed conduit having an inlet at one end for material to be conveyed and an outlet at its other end; and (b) a multi-layered, gas permeable member that serves as a gas distributor mounted in said conduit dividing the conduit into an upper material chamber and a lower plenum chamber, said lower plenum chamber adapted to be connected to a source of gas under pressure; said member permitting the passage of said gas from the lower plenum chamber into the upper material chamber to aerate and fluidize material in the upper material chamber whereby the thus fluidized material will flow downwardly above said upper gas distributor member at a predetermined slope from said inlet to said outlet by gravity; said multi-layered, gas permeable member comprising (i) an upper layer having a substantially smooth top side adjacent to the upper material chamber and comprising a gas permeable, porous medium capable of withstanding temperatures up to about 2900° F.; (ii) a middle layer having a top side adjacent to the upper layer and a bottom side, said middle layer comprised of a gas permeable insulation material that maintains its physical integrity when exposed to temperature differentials up to about 2900° F. between its upper side and its bottom side; and (iii) a lower layer adjacent to the bottom side of the middle layer for supporting the top and middle layers, said lower layer comprising a substantially flat plate having a plurality of openings therethrough through which fluidizing gas can pass.