转炉钢渣中铁组分的氧化改质与磁选回收

Oxidation modification and magnetic separation of iron component in converter steel slag

在不同工艺参数下对转炉钢渣进行了固相氧化改质,并对改质后钢渣进行了磁选处理,分析对比了干式磁选和湿式磁选对改质钢渣的磁选效果。实验结果表明:通过氧化改质处理,能够使钢渣中无磁性铁氧化物向有磁性镁铁尖晶石发生转变,后者可通过磁选进行有效分离。原钢渣进行氧化改质的最佳加热温度和气体通入速率分别为1 100℃和7.5 L·min^(-1)。钢渣通过固相改质后,更容易获得高回收率的高品位精矿,对钢渣的磁选宜为湿式弱磁选,实验范围内磁选工艺的最佳磁感应强度为0.102 T。在加热温度1 100℃,保温时间30 min,气体通入速率7.5 L·min^(-1)的条件下,改质钢渣产率达到22%,铁品位达到62%,回收率达到64.95%。

The modification of basic oxygen furnace（BOF） slag is carried out under different technological parameters, followed by the magnetic separation. The effect between dry magnetic separation and wet magnetic separation on modified steel slag is analyzed and compared. The experimental results show that the non-magnetic ferrite can be transformed into magnetic ferromanganese spinel by oxidative modification, which can be separated by magnetic separation. The optimal heating temperature and gas flow rate of the modification process are 1 100 ℃and 7.5 L·min^（-1）,respectively. It is easier for modified slag to obtain high-yield and high-grade concentrate, the magnetic separation of steel slag should be wet weak magnetic separation, and the best magnetic flux density within this experimental range is 0.102 T. Under conditions with heating temperature of 1 100 ℃, holding time of 30 min and gas flow rate of 7.5 L·min^（-1）, yields of steel slag is 22%, iron grade in concentrate is 62% and recovery rate is 64.95%.