WNAG Pengtao;WANG Naiji;CHENG Xiaolei;WANG Yongying;LIANG Xing;

• 1:China Coal Research Institute Company of Energy Conservation
• 2:State Key Laboratory of Coal Mining and Clean Utilization
• 3:National Energy Technology & Equipment Laboratory of Coal Utilization and Emission Control

Abstract：

In order to investigate the effect of air-staged low-nitrogen combustion technology on combustion process of pulverized coal industrial boilers and reduce the initial emission of NO_x,the influence rule of air classification depth on boiler combustion and initial emission of NO_x was firstly explored through the numerical simulation in a 40 t/h pulverized coal industrial boiler in China Coal Research Institute Company of Energy Conservation.The accuracy of simulation results was verified by engineering test. The simulation results show that the average temperature at outlet of burner increases from 980 K to 1 530 K with third-air ranging from 0 to 50%,and the temperature distribution is more uniform as the air classification depth deepens.Besides,the flow velocity reduces about 10 m/s,and the initial emission concentration of NO_x in boiler is reduced from the maximum of 697 mg/m~3 under unstaged conditions to 30% at 424 mg/m~3 under thirdair conditions with a reduction of approximately 39%. The engineering experiment shows that the initial emission concentration of NO_x is409 mg/m~3 when the proportion of third-air is 30%,which is less than 5% difference with the numerical simulation results.That is,the numerical simulation can predict the boiler combustion and NO_x emissions well.Air-staged low-nitrogen combustion technology can effectively reduce the initial emission concentration of NO_x in pulverized coal industrial boilers.

Key Words： pulverized coal;industrial boiler;deep air-staged technology;nitrogen oxides;numerical simulation

Abstract:

Keywords:

Foundation: 煤炭科学研究总院面上资助项目(2016ZYMS007);煤炭科学研究总院科技发展资助项目(2016CX02)

Authors: WNAG Pengtao;WANG Naiji;CHENG Xiaolei;WANG Yongying;LIANG Xing;

DOI: 10.13226/j.issn.1006-6772.18051402

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