GB1038079A - Installation for heating fine granular substances, particularly powdered cement raw material - Google Patents

Abstract

1,038,079. Preheating and charging cement raw materials. KLOCKNER-HUMBOLDTDEUTZ A.G. Oct. 4, 1963 [Oct. 18, 1962], No. 39172/63. Heading F4B. Apparatus for preheating and charging fine granular material comprises two or more component gas flow paths through ducts, each leading to an associated dust separator of one or more stages such that the hot gases flow along " parallel " component lines through each separator stage whereas the material passes through each separator of each stage in " series ". Hot gases from a rotary kiln 1 are divided into two component gas streams flowing in parallel through cyclone dust separators, the respective gas paths being on one hand duct 3, cyclone 5, duct 16, cyclone 17, duct 18, cyclone 19, outlet duct 20, and, on the other hand duct 4, cyclone 6, duct 22, cyclone 23, duct 24, cyclone 25, outlet duct 26. Both outlet ducts converge into a common duct 21 coupled to an extraction fan 27. Raw cement material is fed from a screw conveyer 29 and bucket wheel 30 through the pipe 31 into the conduit 18 between cyclones 17 and 19 and is entrained by the hot gases and passes into the cyclone 19. The separated powder falls through the discharge pipe 32 into the duct 24 and passes in a like manner through cyclone 25, pipe 33, duct 22, cyclone 23, pipe 34, duct 16, cyclone 17, pipe 35, duct 3, cyclone 5, pipe 14, duct 4, cyclone 6 and pipe 15 to the kiln 1. Thus the two component gas streams pass in parallel through each separator stage whereas the material passes in series through each separator of each stage. The embodiment illustrated in Fig. 1 (not shown) employs only one cyclone stage. In the alternative embodiments, Figs. 3 and 4 (not shown), the gas ducts from the kiln are formed into a common duct 37 into which the discharge pipe from the second stage is connected. In the former embodiment, Fig. 3, the discharge pipe leads to the base of the common duct and the discharge from the first stage cyclones passes via pipes 42 and 43 to the kiln through return pipe 44. In the latter embodiment, Fig. 4, the second stage discharge pipe 36 leads into the top of the common duct 37 and the discharge pipe from the first stage cyclone leads into the base of this duct, the other first stage cyclone discharge duct 47 returning to the kiln. There may be more than two component gas paths and more or less than three separator stages.