Currently, the method of SNCR (Selective Non-Catalytic Reduction) is generally adopted by the developed countries for NOx removal. With its short period, low investment and average NOx removal efficiency, it is suitable for the retrofit of small and medium utility boilers, which fits China's situation.In this thesis, based on the experimental results obtained from CRF(combustion Research Facility), numerial simulation was done to investigate the process of in-furnace combustion and NOx removal. Firstly, the numerical simulation was done on the in-furnace combustion in order to find a suitable temperature region for SNCR. Then, with proper simulation of the temperature distribution, a method of post-simulation was done to simulate the NOx formation process. After that, the gas component concentration was output to be set as the entry parameters of SNCR.Based on the simplified combustion model and making the results of combustion and NOx formation simulation as the entry parameters, numerical simulation of SNCR was done. With NH3 as the reducing material, the influence of the temperature and NH3/NO ratio on the NOx removal efficiency was attained by the simulation of SNCR process. The comparison between the simulation and the experimental results was also carried out. It lend support to the optimization design of SNCR system.
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