FIELD: ferrous metallurgy. SUBSTANCE: device has the first single furnace with fluidized bed for drying and preliminary heating of finely-divided iron ore in fluidized state and the first cyclone for trapping the particles of finely-divided iron ore entrapped by gas effluent from this furnace; the second single furnace with fluidized bed for preliminary reduction of finely-divided iron ore dried and preliminarily heated in the first furnace; the second cyclone for trapping particles by gas effluent from the second furnace with fluidized bed; the third twin furnace with fluidized bed designed for final reduction of coarse, medium and fine preliminarily reduced ore particles; the third cyclone for trapping medium and fine particles entrapped by gas effluent from the first reaction furnace of the third furnace with fluidized bed; and the fourth cyclone for trapping ultrafine particles of iron ore entrapped by gas effluent from the second reaction furnace of the third furnace with fluidized bed. Each furnace has its own design. Furnaces are interconnected in a definite manner with one another to allow separate reducing of coarse, medium and fine fractions of ore in separate reduction furnaces. EFFECT: higher efficiency; increased efficiency of gas consumption. 6 cl, 6 dwg, 6 tbl
