微细铁颗粒的单体解离特性和选择性回收工艺

研究了直接还原熟料中微细铁颗粒的赋存形式和选择性回收工艺.发现尾渣中铁的赋存形态主要为微细粒的单质铁;直接还原熟料中小于5μm的细连生体和铁颗粒很难通过磁选回收,但大于10μm的粗铁颗粒可以回收.为了兼顾粉末铁的品位与回收率,需要对不同赋存状态的铁颗粒进行选择性回收.提高粗连生体的单体解离度,有针对性地回收其中的铁颗粒,是提高粉末铁回收指标的关键.提高磁选场强可提高粉末铁回收率,但降低粉末铁品质.利用正交试验对工艺参数进行了优化,在优化条件下粉末铁中TFe质量分数和铁回收率分别为92.91%和92.03%.

Monomer dissociation characteristics and selective recovery technology of micro-fine iron particles

This article studies the existing form of iron particles in direct reduction clinker and their selective recovery technology. It is found that the existing form of iron in tailings is micro-fine iron particles. In direct reduction clinker, the particles greater than 10μm can be recovered by magnetic separation, however those less than 5μm cannot. Considering both the grade and recovery of iron powders, it is necessary to conduct a selective recovery of different types of iron powders. Increasing the monomeric liberation of coarse intergrowths and recovering iron particles specifically from the intergrowths are the key to improve the recovery index of iron powders. Though the recovery of iron can be improved by increasing the magnetic field intensity, the quality of iron powders reduces. Technological parameters have been optimized for the separation by orthogonal test. Under the optimization condition the TFe content of iron powders and the recovery rate of iron is 92.91% and 92.03%, respectively.