煤泥和原煤的燃烧动力学特性实验研究

Experimental research on combustion kinetic characteristics of coal slime and raw coal

利用热重分析法,研究了煤泥和原煤在不同升温速率与不同氧体积分数下的燃烧特性差异。结果表明:升温速率的增加能够提高着火温度与燃尽温度,升温速率越快,着火温度与燃尽温度越高,燃烧特性指数越大,燃烧特性越好;综合燃烧特性指数S与氧体积分数呈线性关系,相同升温速率下,氧体积分数越高,燃烧特性指数越大;相同条件下原煤的燃烧特性参数要远大于煤泥,且氧体积分数对原煤燃烧特性参数的影响小于对煤泥的影响;煤泥的活化能分布随氧体积分数的增加先增大后降低,而原煤的活化能分布随氧体积分数的增加一直增大;提高升温速率与增加氧体积分数均有助于原煤和煤泥的燃烧,且煤泥受氧体积分数的影响更加明显。

The combustion characteristics of coal slime and raw coal were investigated through thermogravimetric analysis at different heating rates and oxygen volume fractions. The results show that, increasing the heating rate will increase the ignition temperature and burnout temperature. Meanwhile, the combustion characteristic index will also increases, which means a better combustion performance. The comprehensive combustion characteristic index S is basically linear with the oxygen volume fraction. The combustion characteristic index increases with the oxygen volume fraction at the same heating rate. The combustion characteristic index of raw coal is much larger than that of the coal slime under the same conditions, and the effect of oxygen volume fraction on the combustion characteristic index of coal is weaker than that of the coal slime. With the increase of oxygen volume fraction, the activation energy distribution of coal slime increases at first and then decreases, while that of the raw coal keeps increasing. The experimental results indicate that increasing the heating rate and oxygen volume fraction both contribute to the burning of raw coal and coal slime, and the influence of oxygen volume fraction on coal slime’s combustion is more obvious than raw coal.