锰矿洗炉对高炉渣的影响及其机理

Influence and mechanism of flushing furnace by manganese ore on blast furnace slag

利用锰矿洗炉是处理高炉炉缸堆积事故的重要方法之一。对MnO质量分数不同时的炉渣性能及其机理进行研究,应用熔体物性综合测定仪测定含MnO炉渣的黏度及熔化性温度,并提出稳定性指数的概念;使用X射线衍射仪(XRD)分析含MnO炉渣的物相组成;利用拉曼光谱仪研究含MnO炉渣的微观状态。试验结果表明,锰矿洗炉过程中,炉渣中MnO最佳质量分数应为1.5%左右,此种炉渣在1 480℃时的黏度为0.25 Pa·s左右,熔化性温度为1 340℃左右,稳定性较强,可以满足洗炉要求。锰矿洗炉的机理是炉渣中生成了锰橄榄石类硅酸盐低熔点物质,增大了液态炉渣的过热度;并且随着自由氧离子浓度的增加,其促使复杂硅氧四面体网络结构解聚为简单硅氧四面体结构,炉渣由复杂结构向简单结构发展,从而显著降低炉渣黏度,达到洗炉的目的。

Flushing blast furnace by manganese ore was one of the important methods to deal with the accident of blast furnace hearth accumulation. So based on the previous studies,the properties and mechanism of the slag with different w（（MnO）） were researched,which included the viscosity,melting temperature and stability index by melting physical properties comprehensive detector,the phase composition by XRD and the microstate by Raman spectrometer were conducted. The experiment results showed that during the process of flushing blast furnace,the best w（（Mn O）） in the slag was around 1.5%,so that the viscosity of this slag was about 0.25 Pa·s at the temperature of 1 480 ℃,the melting temperature was around 1 340 ℃ and the stability was strong,these were all good enough to meet the requirements of flushing blast furnace. The mechanism of flushing blast furnace by manganese ore was that the low melting point material of manganese olivine silicate which increased the superheat degree of the liquid slag had been generated in the slag. What＇s more,the concentration of the free oxygen ions that could promote the depolymerization of complex silicon oxygen tetrahedron network structure to simple silicon oxygen tetrahedron structure increased,which could significantly reduce the viscosity of slag by changing the slag microstate from complex to simple state in order to achieve the purpose of flushing blast furnace.