电炉渣高温改性过程中铁物相的行为变化  

The Behavior Change of Iron Phase in Electric Furnace Slag Modified at High Temperature

作　　者：匡敬忠[1] 刘德华[1] 曾军龙[1] 李永峰[1] 

机构地区：[1]江西理工大学,江西赣州341000

出　　处：《矿冶工程》2014年第3期61-64,68,共5页Mining and Metallurgical Engineering

基　　金：江西省青年科学家培养对象(井冈之星)资助项目(21112BCB23020)

摘　　要：通过高温改性回收电炉渣中的铁,研究了保温时间、缓冷时间、盐类添加剂及其用量对电炉渣中铁物相转变的影响,利用XRD衍射分析电炉渣改性前后的铁物相的赋存状态,并对改性焙烧产物进行磁选验证了改性效果。结果表明:焙烧温度1 350℃,焙烧时间120 min,缓冷时间180 min,盐类添加剂用量为w(66.7%CaCO3+33.3%MgCO3)/w(SiO2)=3/4条件下,电炉渣中铁橄榄石全部转化为赤铁矿和磁铁矿,经磁选可得品位50.12%、回收率72.67%的铁精矿。焙烧时间的增加有利于磁铁矿物相的析出和长大;延长缓冷时间促进赤铁矿物相的形成;碳酸钙和碱式碳酸镁的组合使用有利于提高铁精矿品位和回收率。Test on recovering iron from electric furnace slag after being modified by calcination at a high temperature was conducted, for studying effects of the holding time, slow-cooling time, saline additives and their dosage on the iron phase transition of electric furnace slag. The occurrence of iron phase in electric furnace slag before and after modification was analyzed with XRD. Then the product obtained after the modification by calcination was subjected to magnetic separation for verifying the modification effect of iron concentrate. Results showed that after 120-min roasting at a temperature of 1 350 ℃ plus 180-min slow cooling, with the dosage of salt additives being w（66.7%CaCO3＋ 33.3% MgCO3 ）/w （SiO2 ）= 3/4, fayalite in electric furnace slag was transformed into hematite and magnetite. And the following magnetic separation process could produce an iron concentrate grading at 50. 12% with recovery of 72.67%. It is concluded that prolonging roasting time can benefit the precipitation and development of magnetite phase, and prolonging slow-cooling time can facilitate the formation of hematite phase. Furthermore, the combined use of calcium carbonate and basic magnesium carbonate can be beneficial to improving both grade and recovery of iron concentrate.

关 键 词：电炉渣 改性焙烧 铁物相 磁选 

分 类 号：TF111[冶金工程—冶金物理化学]