煤中矿物质对其半焦反应活性的影响

本工作考察了大同煤、神木煤、蔚县煤镜质组酸洗前后半焦反应活性的变化。煤酸洗后灰分的失去导致了半焦反应活性的降低。煤种不同,制焦条件不同,矿物质在半焦中的分布形式及存在状态不同,对半焦反应的催化能力也不同。煤种不同,煤中矿物质对半焦活化能的影响彼此不同。在整个反应历程中,具有催化作用的矿物质对半焦活化能的影响并不是恒定的。煤酸洗后半焦反应活性的降低是活化能和指前因子共同变化的结果。

THE EFFECT OF MINERALS ON THE REACTIVITY OF THE CHAR FROM RAW AND DE-ASHED COAL

The reactivity of the char prepared from raw and de-ashed coal was investigated. The reactivity of the chars was measured by non-isothermal thermo-gravimetric analysis in 0.1 MPa air. The reactivity of the chars from raw coal is higher than the chars from de-ashed coal. The catalytic ability of minerals are different from each other, because the dispersion degree and existence of minerals in the chars prepared from different coals under different conditions are different. The effects of minerals on the activation energy of the chars from different coals also differ from each other. The catalytic effect of minerals in char is not constant with the development of oxidation. The decrease of the reactivity of the chars from de-ashed coal are due to the change of activation energy and preexponential factor caused by the lost of minerals.