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气泡相和乳化相间的传热传质对超低浓度煤层气在流化床中的燃烧有重要的影响。基于流化床内能量平衡和质量平衡的建立了数学模型,结合催化动力学实验,研究了相间传热传质系数的变化,分析了床层温度、颗粒粒径、气泡直径、进气甲烷浓度对相间的传热传质特性的影响。研究表明:床层温度、颗粒粒径增加时,传热系数减小、传质系数增大、出口处无量纲甲烷浓度减小;存在一个临界气泡尺寸使相间的传热系数最大,颗粒粒径增大时,临界气泡尺寸略减小、出口处无量纲甲烷浓度增加;进气甲烷浓度对传热传质系数影响较小。
The heat and mass transfer between bubble phase and emulsion phase has an important influence on the combustion of ultra-low concentration CBM in the fluidized bed. Based on the energy balance and mass balance in a fluidized bed, a mathematical model was established, and the change of heat and mass transfer coefficient between the two phases was studied based on the experiments of catalytic kinetics. The effects of bed temperature, particle size, bubble diameter, On the heat and mass transfer characteristics of the impact. The results show that when the bed temperature and particle size increase, the heat transfer coefficient decreases, the mass transfer coefficient increases and the outlet dimensionless methane concentration decreases. There exists a critical bubble size that maximizes the interphase heat transfer coefficient and the particle size Increasing, the critical bubble size decreases slightly, outlet outlet outlet outlet outlet outlet outlet Dimetric methane concentration increases; inlet methane concentration on the heat and mass transfer coefficient less.