粒径对造气炉内煤燃烧反应的影响及动力学分析

Effect of Particle Size on Coal Combustion Reaction in Gas Generator and its Dynamic Analysis

为了克服喷吹煤粉给高炉冶炼带来的不利影响,提出了由造气炉燃烧普通煤经过气化产生煤气,自风口喷入高炉替代喷吹煤粉的新工艺。研究煤球粒径对炉内燃烧反应的影响及动力学分析。根据造气炉反应特点,采用实验室高温气固反应试验台进行粒径6~18mm下的煤燃烧试验,结果表明,随着粒径的增大,完全燃烧时间逐渐升高。利用未反应核模型进行动力学分析,得出:改变粒径不能影响煤球燃烧反应的限制性环节,在不同粒径下,限制性环节均为外扩散和化学反应混合限制;另外,通过计算得出,随着煤球粒径的增大,化学反应速率常数逐渐降低。

In order to overcome the adverse effects of pulverized coal injection on blast furnace smelting, a new process of burning ordinary coal from gas-m aking furnace through gasification to produce gas, and spraying from blast furnace into blast furnace instead of pulverized coal pow der is proposed. The effect of coal ball size on the com bustion reaction in the furnace and the kinetic analysis were studied. According to the characteristics of gas-m aking furnace reaction, the coal com bustion test with particle size of 6~18mm was carried out by using laboratory high-tem perature gas-solid reaction test bench. The results show that the com plete com bustion time increases with the increase of particle size. Using the unreacted nuclear m odel for kinetic analysis, it is concluded that changing the particle size can not affect the restrictive link of the briquette com bustion reaction. Under different particle sizes, the limiting links are the diffusion limits of the external diffusion and chemical reaction;As the particle size of the briquettes increases, the chemical reaction rate constant decreases.