US 4,747,879 A · Method and apparatus for the thermal treatment of meal-like raw materials

Abstract

A method and apparatus for the thermal treatment of pulverulent raw material in the manufacture of cement clinker including passing raw material first through a multi-stage preheating treatment including cyclones arranged following one another, next passing the material through a reaction stack for calcination, then passing the material through a sintering kiln and thereafter through a clinker cooler, the exhaust air from the clinker cooler and the exhaust gas from the sintering kiln being passed parallel to the each other with the material discharged into conduits respectively carrying the discharged clinker cooler air and the sintering gases with burners in the conduits and the gases thereafter passing up through the reaction stack and then through a separator and into the sintering kiln.

Claims20

Dependent claims

A method for the thermal treatment of pulverulent raw material in the manufacture of cement clinker wherein the material is preheated, calcined, sintered and cooled, comprising the steps:

passing the gas stream from the sintering stage and the airstream from the cooling stage into a common reaction zone for calcination of the raw material;
introducing a preheated raw material into at least one of the streams;
and bringing said streams together in a substantial flow retaining the cross-section of the streams and flowing said streams at substantially the same velocity so that a partial mixing of the two streams occurs only at the boundary layer between the streams.

An apparatus for the thermal treatment of pulverulent raw material for the manufacture of cement clinker wherein the material is preheated, calcined, sintered and cooled, comprising in combination:

a preheating stage including a sequence of cyclones following one another;
means for introducing raw material into said preheating stage;
a calcination stage connected to receive the material from the preheating stage and including a reaction stack;
a sintering kiln connected to receive the material from the calcination stage;
a clinker cooler connected to receive the material from the sintering kiln;
an exhaust air conduit leading from the clinker cooler and carrying heated air from the clinker cooler;
an exhaust gas conduit leading from the kiln;
and
said conduits having portions extending substantially parallel to each other and connected to discharge to the reaction stack whereby the conduits discharge into the reaction stack with the streams flowing therethrough flowing parallel into the reaction stack and mixing at the boundary layer of the streams.

6 more elements

Dependencies are inferred from the claim text.

Method and apparatus for the thermal treatment of meal-like raw materials

Life of this patent

Method and apparatus for the thermal treatment of meal-like raw materials

Life of this patent

Abstract

Claims20