Combustion and NOx Emission Characteristics of Coal Slime Solid Waste at Different Feeding Positions

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  • 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
    3. Dalian National Laboratory for Clean Energy, Dalian 116023, China
    4. School of Engineering Science, University of Science & Technology of China, Hefei 230026, China
    5. Shandong Huaju Energy Co. Ltd, Jining 273500, China

网络出版日期: 2023-11-26

基金资助

This work was financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA21040100).

版权

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2023

Combustion and NOx Emission Characteristics of Coal Slime Solid Waste at Different Feeding Positions

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  • 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
    3. Dalian National Laboratory for Clean Energy, Dalian 116023, China
    4. School of Engineering Science, University of Science & Technology of China, Hefei 230026, China
    5. Shandong Huaju Energy Co. Ltd, Jining 273500, China

Online published: 2023-11-26

Supported by

This work was financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA21040100).

Copyright

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2023

摘要

循环流化床(CFB)锅炉燃烧煤泥的NOx排放难以满足中国日益严格的标准,煤泥从炉顶进料导致炉膛和旋风燃烧不均匀,停留时间短以及尾受热面过热等问题。本文研究了加料位置对煤泥燃烧均匀性和污染物排放特性的影响。实验结果表明,前墙给料时煤泥燃烧更加均匀,较长的停留时间有利于控制NOx排放。在锅炉温度和过量空气系数基本相同的情况下,前墙给料和炉顶给料的NOx原始排放量分别为45.0 mg·m-3和70.7 mg·m-3,前墙给料的NOx排放量减少了36.35%,达到了超低NOx排放标准。采用前墙给料,大大降低了NOx的原始排放,在实际应用中大大节约了运行成本。

本文引用格式

ANG Xueting, SONG Guoliang, YANG Zhao, WANG Chao, JI Zengcai, ZHANG Xingshun . Combustion and NOx Emission Characteristics of Coal Slime Solid Waste at Different Feeding Positions[J]. 热科学学报, 2023 , 32(6) : 2351 -2360 . DOI: 10.1007/s11630-023-1863-2

Abstract

The NOx emission of coal slime burned in circulating fluidized bed (CFB) boilers could hardly meet the increasingly strict standards in China. Feeding coal slime from the top of furnace led to uneven combustion in furnace and cyclones, short residence time and overheated tail heating surface. The effects of feeding positions on the combustion uniformity and pollutant emission characteristics of coal slime were studied. The experimental results showed that the coal slime combustion was more uniform when feeding from the front wall and longer residence time was conducive to the control of NOx emission. When the boiler temperature and excess air ratio were almost identical, the initial NOx emissions were 45.0 mg·m–3 and 70.7 mg·m–3 when feeding from the front wall and the top of furnace, respectively; the NOx emission was cut down 36.35% when feeding from the front wall, successfully meeting the ultra-low NOx emission standard of China. The adoption of feeding from the front wall greatly reduced the original emission of NOx; the operation costs in the practical applications were saved to a large extent.

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