Industrial scale assessment of the predictive quality of a 3D-CFD model for SCR DENOX catalysts

摘要

Reacting CFD modelling has become an indispensable tool for the optimisation of industrial scale combustion equipment in power plants. Therefore, it is straightforward to extend the computer-aided methods to describe and optimise also post-combustion equipment. For this purpose, a modelling approach for the mathematical description of the physical/chemical processes within SCR-catalysts is described in the present paper. This modelling approach is embedded within the framework of a 3D-CFD environment (3D-CFD catalyst model). The 3D-CFD approach is able to provide additional information about the non-uniform space velocity, temperature, and chemical species (e.g. NO, mercury, etc.) distribution before and within the catalyst, which is essential for the realistic description of a full-scale SCR system installed in power plants. Since the 3D-CFD code has to be able to deliver reliable inforation about flue gas conditions of coal-, oil-, and gas-fired firing systems, RECOM's proprietary CFD code RECOM-AIOLOS jointly developed with a modelling group at IFK/Stuttgart University is used in the present work. The predictive quality of RECOM-AIOLOS has been extensively verified in numerous measuring campaigns in full-scale firing systems of power plants. In order to develop a reliable 3D-CFD catalyst model, the model parameters have been calibrated using a large number of micro- and bench-reactor data from lab-scale experiments. After the calibration process, the predictive quality of the 3D-CFD catalyst model has then been verified by validation with experimental data from full-scale power plants. The full-scale validations comprised honey-comb as well as platen catalysts.