为实现小型天然气锅炉低氮排放，针对0.2 MW天然气锅炉，开发出一种以烟气再循环和燃料预混贫氧燃烧技术为基础的小型天然气锅炉专用低氮燃烧器。对此燃烧技术的排放特性进行了数值模拟研究，分析了烟气再循环率、预混段长度以及多孔板孔径等因素对NOx排放量的影响，搭建了相应的实验台进行热态实验并对其设计合理性进行了验证。被热态实验证实的小型天然气锅炉低氮燃烧器较佳结构参数为：烟气再循环率为20%，相应烟气速度为35 m/s，预混段长度为100 mm，多孔板孔径为5 mm，燃料喷孔孔径为3 mm。研究结果表明：小型天然气锅炉低氮燃烧器采用贫氧预混燃烧技术和烟气再循环技术能够显著降低NOx排放量，与传统燃烧器相比，NOx排放量减少68%。

Aiming at 0.2 MW natural gas boiler, based on flue gas recirculation and lean oxygen fuel premixed combustion technology, a special low nitrogen burner for smallscale nature gas boiler was developed for the purpose of realizing low nitrogen emission of smallscale natural gas boiler. Compared with the exhaust characteristics of the combustion technology,the numerical simulation study was carried out, the effects of flue gas recycling rate, the length of premixed section and the aperture of porous plate on the NOx emission were analyzed, and the corresponding experimental bench was constructed to conduct the hot state experiment and verify the rationality of the design. The optimum structural parameters of low nitrogen burner of smallscale natural gas boiler confirmed by the hot state experiment were as follows: the flue gas recycling rate was 20%, the relevant speed of flue gas was 35 m/s, the length of premixed section was 100 mm, the aperture of porous plate was 5 mm, and the fuel injection hole diameter was 3 mm. The research results show that low nitrogen burner of smallscale natural gas boiler can significantly reduce NOx emission by using lean oxygen premixed combustion technology and flue gas recirculation technology,compared with traditional burners,NOx emission is reduced by 68%.

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