【作者】 王赞娥；

【导师】 李瑞扬；

【作者基本信息】 哈尔滨工业大学 ， 热能工程， 2007， 硕士

【摘要】 选择性非催化还原法(Selective Non-Catalytic Reduction,简称SNCR)是目前发达国家普遍采用的烟气脱硝方法,是一种建设周期短、投资少、脱硝效率中等的烟气脱硝技术,它比较适合于对中小型电厂锅炉的改造,适合我国国情。本文是在CRF(Combustion Research Facility)实验台热态实验的基础上,对炉内燃烧和SNCR脱硝反应过程进行数值模拟。首先对CRF实验台炉内燃烧过程进行数值模拟,得出适宜SNCR反应的温度区域。在合理模拟了炉内燃烧过程后,采用后置处理方法模拟计算了污染物NOx的生成过程,得出烟气中各组分浓度的分布并将其数值输出,作为SNCR脱硝反应过程模拟的入口条件。本文在对燃烧模型简化的基础上,以燃烧及NOx生成模拟得出的结论作为入口条件,进行了SNCR过程的数值模拟。只考虑还原剂为NH3的情况,通过对SNCR过程的模拟得出了温度和氨氮摩尔比对脱硝效率的影响,并与实验结果进行对照。为SNCR烟气脱硝系统的优化设计提供了一定的帮助和指导。更多还原

【Abstract】 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.更多还原