PURPOSE: To reduce sintered ore excellent in property of reduction degradation impellent without lowering the sintering yield by adjusting the grain size of lime stone in the raw material in a specific range, at the time of producing the sintered iron ore in a sintering machine provided with a segregation intensifying type charging device.
CONSTITUTION: At the time of producing the sintered ore for blast furnace by sintering powdery raw material with composition composed of the powdery ore as the main component and coke, lime stone and return fines, the grain size segregation in the layer thickness direction of the sintering raw material is intensified with the segregation intensifying type charging device, and also, the ratio of 3-5mm grain size part in the used lime stone is adjusted to be in the range of 10-30% to the whole charging quantity of the lime stone. While avoiding the lowering of the sintering yield caused by insufficient slagging because of too large grain size of the lime stone, i.e., insufficient reaction with the iron ore, the sintered ore excellent in the property of the reduction degradation impellent is produced in the high productivity.
YOSHIDA HITOSHI
SAKURAGI JUNICHI
