Potential of CCS Technologies for reducing CO2 Emissions in Cement Production
| Project Leader: | Professor Dr-Ing Alfons Kather |
| Research Assistant: | Dipl-Ing S Oberhauser |
| Duration: | 01.02.2009 - 31.01.2013 |
The project, funded by Industry, consists of the following key activities.
Process Analysis and Model Generation
On the basis of a detailed analysis the possibility to adapt the conventional cement production process to the Oxyfuel technology will be investigated. This is based on realistic process simulation by means of, for example, AspenPlus®. Through the model the mass and energy flows in a typical cement production plant will be analysed at industrial scale. The modelling will be validated with data from real cement plants. The simulation will allow determination of the most significant influence parameters on the CO2 and energy balances of the overall process.
Development of a Cement-Oxyfuel concept
At first the heat supply of the clinkering process will be adapted to Oxyfuel operation. Under consideration of all typical process parameters this necessitates an air separation plant and the introduction of exhaust recirculation. Without changing significantly the rest of the plant, it will be possible to identify if it is at all possible to obtain an exhaust gas with the composition that satisfactory CO2 removal necessitates. Furthermore, it will be investigated where in the unaltered process these changes will have to be implemented at best. Based on this first plant concept different configurations will be studied, aimed at obtaining with the Oxyfuel technology a maximum CO2 separation rate with high CO2 purity.
Evaluation of the newly developed concept for CO2-free cement production
The plant configuration which is most realistic for practical application will be analysed further, in terms of the additional costs that CO2 removal introduces, and as regards component adaptation and retrofitting. The investigation will extend to also model the operating characteristics which are to be expected during start-up or turn-down, or with varying loading.
Comparison of the Oxyfuel process for cement production with Post-Combustion with chemical stripping
The Oxyfuel process in cement production will be compared through modelling with a downstream Post-Combustion stripping, which uses a chemical solver for CO2 removal. The resulting operation indices of the overall plant process will enable a quantitative comparison between the two CO2 removal approaches and will lead to suggestions on the overall dimensioning of the CO2 separation plant.