关键词: 添加剂, 微细粒赤铁矿, 内配煤, 还原焙烧

Abstract: There is 31.77% iron in a refractory iron ore in Qidong，Hunan Province.Iron mainly exists in form of hematite.For the development and utilization of the ore，the reduction roasting-low intensity magnetic separation method was used for dressing experiment.The results showed that adding coal pellets can improve the reducing atmosphere inside of the ball，iron can be fully reduced by using coal both inside and outside of the pellets；With additive dosage of 3%，m（C）∶m（Fe） is 0.3，small pellets with diameter of 3~5 mm,after dired the pellets,the dosage of the blending coal is 20%，the reduction temperature of 960 ℃，the reduction time of 35 min，iron metallization rate of 86.15% for roasted products will be obtained，by ground the roasted products to 95% passing 0.045 mm，magnetic field intensity of 183 kA/m for low intensity magnetic separation，the iron concentrate with iron grade of 80.23%，9.48% content of SiO₂，iron recovery of 80.78% was obtained，realized high effective recovery of the iron ore resources.

Key words: Additives, Microfine hematite, Coal-containing, Reducing roasting