包钢尾矿配加瓦斯灰微波磁化焙烧—磁选试验

Tests of Microwave Magnetic Roasting-magnetic Separation on Tailings and Gas Ash in Baosteel

包钢选矿厂的尾矿铁品位为17.84％,包钢炼铁厂的高炉瓦斯灰铁品位为31.90％、碳含量为29.18％,为了探索这2种工业固体废渣高效综合利用的途径,以瓦斯灰中的活性焦炭为还原剂,以尾矿和瓦斯灰中的赤铁矿为被还原对象,进行了微波加热还原焙烧工艺条件研究,并对焙烧产物进行了磨选工艺条件优选.结果表明：粒度均为74 ～0 μm的尾矿与高炉瓦斯灰按质量比100：25混合,在570℃下微波磁化焙烧10 min,焙烧产物磨至33～0μm后进行弱磁选（80 kA/m）,可获得铁品位为54.50％、铁回收率为83.20％的铁精矿.因此,包钢的这2种工业固体废渣可进行资源化利用,其经济社会价值巨大.

Fe grade of tailings from dressing plant of Baosteel is 17.84%, and Fe grade of furnace gas ash from Iron- works of Baosteel is 31.90% ,with carbon content of 29.18%. In order to explore the efficient way for comprehensive utiliza- tion of two kinds of industrial solid waste residues, with the active coke from gas ash as reducing agent, and hematite in of tail- ings and gas ash as reduction object, conditioning tests for microwave heating reduction and roasting process were made, as well as the calcined products by grinding process. Results showed that under conditions of grain size of railings ranged from 74 to 0 p,m and mass ratio with blast furnace gas ash at 100：25 ,microwave magnetic roasting under 570 ℃ for 10 min,and calcined product ranged from 33 to 0 p,m by grinding, iron concentrate with iron grade of 54.50% and iron recovery of 83.20% was ob- tained by low intensity magnetic separation （80 kA/m）. Hence, these two kinds of industrial solid waste residues from Baosteel can be used as resources, which brought enormous economic and social value.