Experimental Research on the Roasting of Brazilian Iron Concentrate in a Tube Furnace

In this paper, the method of preparing roasted pellets in a tube furnace is studied. In order to meet the performance standards of blast furnace ironmaking finished pellets, the compressive strength of the pellets must be above 2500 N/P. Hematite and magnetite were used as the main raw materials. The effects of preheating temperature, preheating time, roasting temperature, roasting time and the ratio of magnetite concentrate on the strength of pellets were studied. Under the conditions of preheating temperature of 975 ℃, preheating time of 15 min, roasting temperature of 1300 ℃, roasting time of 15 min, and the proportion of magnetite concentrate of 20–30%, the compressive strength 4948.3 N/P of roasted pellets was reached, thus meeting the performance indicators.