温度对电炉粉尘中ZnO还原挥发的影响

Effect of temperature on the evaporation of zinc from EAF dust reduced using silicon

研究了硅铁还原电炉粉尘过程中温度对锌还原挥发的影响,以中频电磁感应炉为加热设备,实验样品采用XRF、XRD、SEM-eds及化学分析等方法分析。试验结果表明,样品在不同温度下加热时,铁和锌的氧化物同时被还原;随着温度的升高锌的还原挥发率逐渐增加,1 300℃时锌的挥发率为95.90%。硅还原电炉粉尘的反应为固-固反应,金属铁的生成有利于ZnO的还原。粉尘中残留的锌主要以尖晶石固溶体(Mg,Fe,Zn)(Cr,Fe)2O4的形式弥散在金属铁相附近,此外有少量的锌固溶在硅灰石相(CaSiO3)内。

The effect of temperature on the evaporation of zinc from electric arc furnace dust （EAFD） by silicon was investigated. The experiments were carried out in a con- ductive furnace and the samples collected were analyzed with X-ray Fluorescence （XRF）, X-ray Diffraction （XRD） and Scanning Electron Microscope （SEM） equipped Energy Dispersive Spectroscopy （EDS）. The reSults show that when the mixture of sili- con and EAFD was heated, the oxides of ferrum and zinc are reduced simultaneously. The evaporation amount of zinc increases with the temperature rising, and 95.90 % of zinc volatilizes from the furnace in the form of zinc fume at 1 300℃. The reduction of EAFD belongs to solid-solid reaction, and the formation of iron is conducive to the evap- oration of zinc. The part of zinc remaining in the mixtures mainly forms the spinel solid solution （Mg, Fe, Zn） （Cr, Fe）2O4.