弱还原性气氛下Fe_2O_3对高灰熔点煤矿物变化行为影响的研究

Effect of Fe_2O_3 on high melting coal ash mineral behavior under reducing atmosphere

利用XRD、SEM-EDX分析了添加Fe_2O_3的LNC煤灰在高温弱还原性气氛下的矿物组成、微观形貌及微区化学组成变化情况。结果表明,Fe_2O_3的引入抑制了灰渣中莫来石的生成,高温下含铁矿物的生成及低温共熔降低了煤灰熔点;在高Fe_2O_3添加量下,多余的赤铁矿转化为磁铁矿。在弱还原性气氛中,受CO浓度及渣中溶解[O]的影响,未出现单质铁的析出现象。

The behaviors of mineral matters,surface morphologies and micro-chemical composition of LNC coal added with Fe_2O_3 were investigated under reducing atmosphere at high temperature by XRD and SEM-EDX. The results show that the introduction of iron oxide inhibits the formation of mullite,the generation of iron-bearing minerals under high temperature and low temperature congruent melting reduces the ash fusion temperature. The rest of hematite transformed into magnetite with high Fe_2O_3 content. Under reducing atmosphere,iron precipitation was not detected,which was affected by the CO concentration and dissolved oxygen in molten slag.