Patent ID: 8936678
Filing Date: 2015-01-20
Classification: B01D,C04B,F27B,F27D

Abstract:
1. A process for producing cement clinker and for purifying the off-gases formed thereby, wherein cement raw meal is preheated in a preheater by means of hot off-gases, the preheated cement raw meal is burnt in a rotary kiln to form cement clinker, or the preheated cement raw meal is first precalcined before it is burnt in the rotary kiln to form cement clinker, the cement clinker is cooled in a cooler, the hot off-gases used in the preheater are used in a raw mill for treating the cement raw meal, the dust content of a dust-containing mill off-gas formed thereby is reduced in a separating device, and the mill off-gas is subsequently purified in a final process filter upstream of an off-gas chimney, characterized in that the dust content of the mill off-gas is reduced in the separating device to less than 5 g/Nm alkali hydrogen carbonate and/or alkali carbonate is added to and mixed with the portion of the mill off-gas whose dust content has been reduced to less than 5 g/Nm the mixed gas formed thereby is subsequently fed to the process filter for separation of dust laden with pollutants.