Innovative, energy-efficient manufacture of cement by means of controlled mineral formation – Part 2

Summary: The operating experience shows that the temperature and the degree of calcination of the extremely coarse raw mix are increased by up to 10 % after the cyclone preheater and that the cyclone outlets are kept free. The heat transfer in the kiln is increased due to a higher thermal conduction, intensive renewal and an essential increase of the surface of the rolling burning bed. The porous coating layer of the burning zone extended by up to 50 % protects the thermally and chemically heavily stressed kiln lining. The ­foreign ions are redistributed to a large extent between the clinker minerals. Alite was enriched with MgO and its alkalis and Al(Fe)2O3 decreased, which led to a decrease of the periclase content in the clinker.

1 Introduction

Since the portion of the energy costs of the cement production is naturally very high, the cement industry is extremely interested in reducing its energy consumption by means of permanent process innovations and a continuous increase in efficiency. The following enormous technical and economic benefits can be achieved according to the new process by extremely coarse grinding of the raw mix by means of an innovative new design of the wet and dry grinding plants [1-3]:

1. The energy consumption for raw material grinding is reduced by 60 to 80 %.

2. The fuel required for clinker...

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