低氧气氛下煤粉氧化特性实验研究

利用热分析方法,在低氧气氛下进行了高挥发分煤粉的慢速氧化特性实验.借助动力学理论,计算出低温阶段的动力学三因子,结果表明,霍林河褐煤的活化能和指前因子随着反应过程的深入而增加,3种烟煤的活化能和指前因子随着反应过程的深入而减小.实验结果表明,小粒径、低升温速率和高氧气体积分数下煤粉易发生氧化自燃.与φ(O2)=14%相比较,φ(O2)=16%的条件下氧化特性温度的降低值均不超过9℃,如果制粉系统中氧气的体积分数低于16%,可以达到高挥发分煤粉的防爆效果.

Experimental research on oxidation characteristics of pulverized coal in low oxygen environment

Experiment of oxidation characteristics with slow velocity of high volatile coals was conducted under low oxygen conditions by using thermogravimetric analysis method.Three kinetic factors in low temperature was given by the kinetics theory.The results of calculation show that activation energy and pre-exponential factor of Huo lin-he lignite increase and activation energy and per-exponential factor of three kinds of bituminous coals decrease with the reaction process.The experimental results show that the coal is easy to be oxidized and combust under small particle size,low heating rate and high oxygen volumn fraction.Variation of oxidation characteristics temperature is below 9 ℃ under 16% oxygen volumn fraction compared to 14% one.The explosion-proof effect for the high volatile coal can be obtained if the oxygen volumn fraction is below 16% in the milling system.