某难选菱铁矿石直接压球及还原焙烧

Direct Reduction Roasting of Refractory Siderite Ore by Using Direct Pelletization

将某难选菱铁矿石破碎到粒度小于2mm后,加入一定量粘结剂和内配煤与矿石压制成型后再还原焙烧,通过对成球条件、直接还原焙烧过程影响因素和磨矿磁选条件进行实验,确定了最佳条件,最终可得到铁品位92.76%、回收率为85.97%的直接还原铁产品.结果表明,粒度小于2mm的菱铁矿石压球后直接还原可得到高品位、高回收率直接还原铁,还原过程中球未发生粘结、碎裂、膨胀等现象,还原状态良好.

The probability and affecting factors of direct reduction roasting and grinding-magnetic separation of pellets made from refractory siderite ore were investigated.Raw ore crashed into less than 2 mm was mixed with certain dosages of organic binder and reductant coal for pelletizing and then the pellets were roasted in a muffle furnace for direct reduction.The influential factors of pelletization,reduction roasting and grinding-magnetic separation were investigated and the optimum conditions identified.The direct reduction iron with 92.76% iron grade and 85.97% recovery was obtained under this condition.The direct reduction of pellets formed by using ball press from less than 2 mm siderite ore powder can produce high iron grade and recovery of direct reduction iron,there appears no gluing,cracking and expanding,therefore the process of pelletization and direct reduction roasting for iron ore is feasible,and can produce direct reduction iron.