Abstract: This paper studied a two-step method of oxidizing calcination process in order to improve the utilization efficiency of copperas and achieve the energy-saving and environmental production. The analysis of copperas' drying and dehydration curves and TG-DSC (thermogravimetric analysis and differential scanning calarmeutry) curves showed that the best drying temperature was 110℃, and most of the product was FeSO₄·7H₂O. Then the dried products were calcinated at the different temperature. The influences of the calcination temperature on the product recovery, residual sulfur content, the compound morphology of Fe and the distribution of sulfur in the flue gas was investigated. The results showed that when the temperature was 800—900℃, air flow rate was 120L/h, and the constant temperature time was 90min, the amount of residual sulfur in the calcinated product was 0.33% and total Fe was more than 60%. Therefore, the final product could be added into the sinter as iron materials.

Key words: two steps, oxidizing roasting, copperas

摘要： 为提高绿矾综合利用效率,实现节能环保生产,研究了二步法氧化焙烧工艺。第一步,对绿矾进行干燥脱水处理研究,通过对绿矾干燥脱水曲线及TG-DSC曲线的分析可知,绿矾前期干燥脱水的最佳温度为110℃,此时所得产物大部分为FeSO₄·7H₂O;第二步,在不同温度下通空气对第一步的干燥产物进行氧化焙烧,研究了焙烧温度对焙烧产物回收率、残硫量、Fe化合形态及烟气中硫分布的影响,结果在800~900℃、气流量120L/h、恒温时间90min的条件下,最终所得焙烧产物的残硫量为0.33%,总铁(TFe)在60%以上,可以作为炼铁原料配加进入烧结矿,且烟气中的硫得到了回收。

关键词: 二步法, 氧化焙烧, 绿矾