材料期刊网

通过采用热重及反应物岩相观察,研究不同煤种在不同配比下混煤残碳与CO2反应行为,由热重曲线可知：2种煤混合时,在900～1 100℃,混煤实际与加权失重率相差不大,甚至实际失重率小于加权失重率;在1 100～1 200℃,混煤的实际失重率大于加权失重率,最大时相差10%。3种煤混合时,煤粉的实际失重率既与温度也与挥发分有关。得出结论：在1 100～1 200℃时,高炉喷吹混煤反应性更强,焦炭的保护作用更为突出,高炉内煤粉利用率更高。从煤粉碳素熔损反应后形态来看,高煤质煤粉残碳先于低煤质煤粉残碳反应完全。煤粉的挥发分含量不同时,其反应形态也不同：低挥发分的混煤中,烟煤的内孔反应和气泡产生不剧烈;而在高挥发分的混煤中,烟煤残碳反应现象较为剧烈。

Through TG-DTA and reactants petrographic analysis, reaction behaviors between residue chars from dif- ferent kinds of coals and mixed coals and COz were studied. From TG-DTA curves, with two kinds of coals mixed, between 900-1 100 ℃, actual loss ratio was nearly the same with weighting ratio, even less between 1 100-1 200℃, practical loss ratio of mixed coals was higher than weighting ratio, with maximum difference 10 %. With three kinds of coals mixed, practical loss ratio was relevant to temperature and volatile. From results, at high temperature mixed coals injected have better reactivity, thus char is better protected and PCI have better effects. From char pat- terns analysis, residue char of high quality pulverized coal is prior to react than residue char of low quality pulverized coal. Pulverized coal reacting patterns were different according to various volatile contents： with volatile 17 %, inner bore reaction of bituminous coal was not severe, and with volatile 19 %, reside char reaction was fierce accompanied with coking phenomenon.