城市污泥流化床燃烧过程中气态污染物排放特性

doi:10.16085/j.issn.1000-6613.2017-0712

摘要/Abstract

摘要： 在6kW_th鼓泡流化床实验台上进行了城市污泥的燃烧实验，研究了烟气再循环气氛和空气气氛下燃烧温度、过量氧气系数、二次风比率对气态污染物排放特性的影响。研究结果表明：燃烧温度升高，NO排放浓度明显升高，SO₂排放浓度亦呈上升趋势；过量氧气系数提高，NO排放浓度呈显著上升趋势，SO₂排放浓度则呈下降趋势；增大二次风比率，NO排放浓度呈现先降低后升高的趋势，但总体减排效果并不明显，SO₂排放浓度出现少量增长；烟气再循环工况下，NO排放浓度随燃烧温度和过量氧气系数变化的趋势与空气气氛燃烧时一致；烟气再循环率从0增加至1，NO排放浓度明显下降；烟气再循环率达到较高值后，NO排放浓度随之提高而降低的趋势减弱；烟气再循环率逐渐升高过程的前期，烟气中CO浓度出现显著升高；再循环率超过0.3后，CO浓度在一定范围内波动，不再升高。

关键词: 污泥, 烟气再循环, 一氧化氮, 二氧化硫, 流化床

Abstract: The combustion experiments of municipal sludge were carried out on the 6kW_th bubbling fluidized bed test bed to study the effect of combustion temperature, excess oxygen ratio and secondary air ratio on NO and SO₂ emission characteristics in the flue gas recirculation atmosphere and air atmosphere. The results showed that the concentration of NO increased significantly and the SO₂ emission concentration increased with the increase of the combustion temperature. With the excess oxygen ratio increased, the NO emission concentration increased significantly, and the SO₂ emission concentration decreased. Increasing the secondary air ratio, NO emission concentration showed a tendency to decrease first and then increase, but the effect of emission reduction was not obvious, and the SO₂ emission concentration increased slightly. In the flue gas recirculation atmosphere, the change of the NO emission concentration with the combustion temperature and the excess oxygen coefficient was consistent with that of the air atmosphere. With the flue gas recirculation rate increased from 0 to 1, NO emission concentration decreased significantly. When the flue gas recirculation rate reached a high value, the NO emission reduction trend decreased. In the early stage of the increase of flue gas recirculation rate, the concentration of CO in the flue gas increased significantly. When the recirculation rate exceeded 0.3, the CO concentration fluctuated within a certain range and no longer increased.

Key words: sludge, flue gas recirculation, nitric oxide, sulfur dioxide, fluidized-bed

中图分类号:

X705

江子箫, 陈晓平, 蒋志坚, 宋联, 朱葛, 梁财, 刘道银, 马吉亮. 城市污泥流化床燃烧过程中气态污染物排放特性[J]. 化工进展, 2018, 37(01): 368-374.

JIANG Zixiao, CHEN Xiaoping, JIANG Zhijian, SONG Lian, ZHU Ge, LIANG Cai, LIU Daoyin, MA Jiliang. Gaseous pollutants emissions from fluidized bed combustion of municipal sewage sludge[J]. Chemical Industry and Engineering Progress, 2018, 37(01): 368-374.

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