Method and apparatus for preheating the shaped dust or fine-grained materials, in particular cement raw meal.

摘要

Combined counter current uni-directional current cement meal preheater comprises a charger into a part system 1 of the preheater; sepn. from the gas stream in a cyclone; introduction through a cyclone return and a control pipe into a riser pipe and mixing with hot material/gas mixt. coming from a vortex chamber belonging to the part system 2. The material flows are adjustable so that volatile constituents are condensed out from the gas stream and are separated out in a cyclone of (2) from the gas. The gas enters into the riser pipe of (1) and through a cyclone return and a control pipe, into a vortex chamber heated to cause starting of sublimation of volatile constituents; collides with the gas charge/charge mixture from the part system 3 to be further heated so that the volatiles with high sublimation temps. are condensed, followed by introduction into (3) where it is passed through several large dimension shaft steps and then through an inlet duct into the rotary shaft kiln, whilst gas leaving (1) is passed through a dust extractor before being passed into atmosphere. The system ensures that no volatiles are condensed anywhere causing its blockage.