Abstract:In order to study the influence of flue gas circulation conditions on the thermal state and emission reduction mechanism of the material layer, the heat transfer law of gas-solid and the gas flow mechanics, a numerical simulation model of bed temperature and NOx emission of flue gas circulation sintering is established and verified by experiments, which based on the thermodynamics and kinetics of main reactions in flue gas circulating sintering process. The results show that the simulated temperature and gas composition(O2、CO、NO)are in good agreement with the experimental values, and the relative error distribution of material layer temperature and NO emission concentration is within ±5%. According to the analysis of simulation model, the main factors affecting the NO emission in flue gas recirculating sintering are the concentration of O2 and CO. With the decreasing of the concentration of O2 and the increasing of CO, the reaction rate of fuel N oxidation decreases significantly, the reduction rate of NO-CO increases, and the average emission concentration of NO in flue gas decreases.
陈许玲, 郑如月, 范晓慧, 甘敏, 黄晓贤, 季志云. 烟气循环烧结过程料层温度及NOx排放模拟模型[J]. 钢铁, 2020, 55(2): 23-30.
CHEN Xu-ling, ZHENG Ru-yue, FAN Xiao-hui, GAN Min, HUANG Xiao-xian, JI Zhi-yun. Numerical simulation model of temperature and NOx emission in flue gas circulating sintering process. Iron and Steel, 2020, 55(2): 23-30.
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