液态高铅渣直接还原炉内铬镁砖侵蚀研究*

通过液态高铅渣直接还原炉内侵蚀铬镁耐火砖的物理性能检测、化学成分分析以及SEM扫描电镜和EDS能谱检测分析,研究了在高温、强还原性气氛和碱性炉渣等熔炼环境下,还原炉内不同区域铬镁耐火砖的破坏机理。研究发现,液态高铅渣直接还原炉渣线区耐火砖表面损毁主要由熔渣氧化物侵蚀引起;熔池区耐火砖表面为熔渣侵蚀,没有明显的过渡带;高温还原性气体沿耐火砖显气孔进入耐火砖内部是导致炉顶区耐火砖表面结构变疏松的主要原因。通过化学成分以及晶体结构检测分析,发现铅、铜和砷等金属渗透引起的结构性破坏是造成渣线区和熔池区铬镁耐火砖损坏的主要因素;耐火砖内铁氧化物组分被还原引起的结构改变是导致炉顶区耐火砖结构疏松的主要因素。

Corrosion of magnesia-chrome brick in molten rich-lead slag direct reduction furnace

We study the damage of the magnesia-chrome brick in molten rich-lead slag direct reduction furnace at the high temperature, strong reducing atmospheres and basic slag by physical properties testing, chemical composition analysis, SEM examination and Energy-Dispersive Spectrometer (EDS). It was found that the slag oxidation erosion is responsibility for the slag line area brick surface damage, molten slag erosion is the main reason for the molten pool area brick surface damage, and there is no obvious transition zone; and high temperature reducing gas along the firebrick show porosity into the brick inside throat area is the main cause of the brick surface structure becomes loose. Through the analysis of the chemical composition and crystal structure detection, found that the structural damage caused by osmosis of the metal elements such as lead, copper and arsenic is the major factor of the damage to the magnesia-chrome brick at the slag line and the molten. The structures change caused by the reduction reactions of iron oxide is the major factor of loose structure to the magnesia-chrome brick at the top of furnace.