Numerical simulation and experimental verification of chemical reactions for SCR DeNO_x

Abstract

Selective catalytic reduction (SCR) is a major commercial technology for NO_x removal in power plants. There are a lot of complex chemical reactions in SCR reactors, and it is of great significance to understand the internal process of chemical reactions for SCR DeNO_x and study the impact of various factors on NO_x removal efficiency. In this paper, the impact of reaction temperature, ammonia-nitrogen molar ratio and resident time in the catalyst bed layer on NO_x removal efficiency were studied by simulation of chemical reactions. Then calculated results were compared with catalyst activity test data in a power plant, which proved that the simulated results were accurate. As a result, the reaction conditions were optimized in order to get the best removal efficiency of NO, so that we can provide a reference for optimal running of SCR in power plants.

Key words： SCR; NO_x; removal efficiency; chemical reactions; simulation

Acknowledgements

The authors were grateful to the National Basic Research Program of China (973 Program) (Grant No. 2005CB221206), the National High-tech Research and Development of China (863 Program) (Grant No. 2007AA05Z309), the special fund for “The Development and Engineering Application of DeNO_x Catalysts in Coal-fired Power Plants” by scientific research institutes and Projects in China, the HuaNeng Group Program (HNKJ07-G03) and (HNKJ08-H09) of China for their financial support to carry out this study.

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