GB638549A - Improvements in and relating to apparatus for treating solid particulate material - Google Patents

Abstract

<PICT:0638549/III/1> Apparatus for the treatment of solid particulate materials with gases or vapours comprises in combination means for feeding solid particles downwardly into a substantially vertical chamber within which one or more tubular combustion chambers is or are arranged, the assembly being adapted to prevent the flow of solid particles down the interior of the tubular combustion chamber or chambers, means for additionally heating the substantially vertical chamber if desired through its external walls, e.g. by direct firing or by heat exchange medium such as superheated steam and/or flue gases, means for introducing gaseous and/or vaporous medium upwardly into a lower part of the vertical chamber at a rate sufficient to maintain the solid particles in a fluid state, and means for withdrawing solid particles from the lower part of the chamber. The hot gases resulting from the combustion chamber or chambers may be used for treating the solid particles. Wet spent bone char to be revivified passes from hopper 14 to drier 15, having conical bottom 19, where it contacts warm gases from pipe 16, and passes thence to annular space 21, having inner shell 24 with louvres 25, lagged outer shell 23, and central combustion chamber 26, where drying is completed. The char then flows to larger annular space 34 wherein it is maintained in the fluid state by hot gases escaping through channels 30 from refractory lined combustion chamber 26, which is supplied with combustible gas and air at 32 and may have refractory thermal accumulator 29 and external fins to assist heat distribution. The hot char passes down ducts 35, cooled by air drawn through sleeves 36, to hopper 39. The air from sleeves 36 is admixed with hot gases withdrawn through louvres 25 and from the top of space 34 and fed through pipe 16 as drying gas. Specification 638,492 is referred to.