粒径对无烟煤颗粒在循环流化床锅炉中燃尽影响的研究

根据流体动力学理论分析了颗粒径与流化速度的关系，通过利用或建立简单的传热与燃烧模型，定量计算了不同粒径无烟煤颗粒的燃尽时间和一次通过炉膛时的停留时间。计算发现：颗粒燃尽所需时间和一次通过炉膛的停留时间均随颗粒径的增加而增长。但停留时间增长的幅度较缓慢。在较大颗粒径时，提高炉膛温度将大大缩短颗粒的燃尽时间。有利于提高颗粒燃尽率。对于一些较难着火的高变质无烟煤，当颗粒径较小时。预热时间对颗粒燃尽的影响不能忽略。图5表1参8

The Influence of Coal Particle Diameter on the Burning-Out of Anthracite in CFB Boiler

The relationship between the diameter of a coal particle and the velocity of fluid gas is analysed in this paper. With using some simplified heat-transfer & combustion model, the burn-out time and the stay-time(one times through furnace) of a single coal particle in the furnace of CFB were also calculated. The results show that both the burn-out time and the stay-time of a single coal particle increased with the adding of particle diameter, but the burn-out time increase more faster. By big particle, raising the furnace temperatur will shorten sharply the burn-out time,so is beneficial to the burning of particle. For some anthracite with higher ignition temperature, the preheated time as a part of the burn-out time of coal particle should not be ignored, especially when the particle diameter is small. Figs 5, table 1 and refs 8.