Muller C.,Verein Deutscher Zementwerke |
Palm S.,Forschungsinstitut der Zementindustrie FIZ
Betonwerk und Fertigteil-Technik/Concrete Plant and Precast Technology | Year: 2011
Several German cement producers developed and launched CEM II/A-M and CEM II/B-M Portland composite cements according to the DIN EN 197-1 standard to develop better quality concretes in the future. The cement producers made comprehensive development efforts to optimize the new cements and associated manufacturing processes with respect to raw materials and process workflows. The approval procedures defined a new benchmark for developments in terms of technology and testing. The continuous reduction In the clinker ratio of the cement led to an Improvement of the specific material profiles of cement and concrete, with respect to their global warming potentials. The consistent trend toward domestic supply covering an increasing number of cement grades contributed to a significant reduction in the clinker or cement ratio, which amounted to 86% In 1987 and was lowered to 73% In 2008.
Bluhm-Drenhaus T.,Ruhr University Bochum |
Wirtz S.,Ruhr University Bochum |
Scherer V.,Ruhr University Bochum |
Perumalsamy S.,University of Duisburg - Essen |
And 5 more authors.
Cement International | Year: 2011
Using the tools of computational fluid dynamics (CFD), detailed calculations of combustion processes can be performed. Thus the interaction of fuel particles with threedimensional temperature, flow and concentration profiles can be thoroughly analysed. However, with the commercial standard models the special features of solid recovered fuels (SRF) cannot be sufficiently recognized, because they are usually an inhomogeneous mixture of particles with varying properties. In a completed research project, therefore, the influence of SRF on the operation and NOx emissions of a precalciner in the cement industry was studied. An essential part of this was the modelling of the flight behaviour and combustion properties of SRF and the verification of these models with laboratory scale experiments. Measurements in an industrial plant provided data for the comparison with simulation results. The simulation results allow for a more detailed and more extensive analysis of the processes in the precalciner under realistic conditions than would be possible with measurement data alone. Furthermore, plant-specific requirements in the processing of SRF can be derived from them.