Method for comminution of mill feed

摘要

The invention relates to a method for comminution of mill feed, in particular for the cement industry, wherein the grinding material is subjected in a mill, in particular an air swept roller mill, to a grinding-drying with supply of a hot gas, is classified and fed as a dust-gas mixture to a filter for dust separation.;In order to improve the energy balance and to save heat energy which is generated using a hot gas generator it is provided that fresh gas or fresh air, which is admixed for removal of the moisture of the grinding material in a predefinable portion to the recirculated hot gas or process gas, is preheated before admixing. The preheating of the fresh gas takes place in a heat exchanger through transfer of the heat energy of the process gas to be removed which is then discharged at a lower temperature to the environment. The preheated fresh gas is fed to the grinding circuit and admixed to the recirculation gas at the required points, for example as combustion air or via fresh air dampers, before or in the mill.

主权项

1. Method for comminution of mill feed, wherein the mill feed is subjected to a grinding-drying process in a mill with supply of a hot gas, is classified and fed as dust-gas mixture to a filter for dust separation, and
wherein after the filter and a mill fan the hot gas is branched off as hot exhaust gas and discharged via a flue to the environment, while a portion of the hot exhaust gas is fed back to the mill as recirculation gas after mixing-in of fresh air, wherein at least a portion of the fresh air fed to the grinding-drying process is preheated before admixing to the recirculation gas, for the preheating of the fresh air at least a portion of, the hot exhaust gas to be fed to the flue is used and the hot exhaust gas used for preheating the fresh air is discharged at a lower temperature to the environment via the flue.