RAW MATERIAL CHARGING METHOD TO BLAST FURNACE

PURPOSE:To maintain the specified time series grain size pattern between batches with ease and good accuracy in an actual operation by measuring the grain size pattern of the raw materials charged into a blast furnace with time and adjusting the grain size pattern of the raw material of the succeeding batch with the deviation from the intended grain size pattern. CONSTITUTION:The charging raw material 2-1 distributed from a moving chute 1 is stored in a hopper 3. The grain size pattern of the charging raw material 2-2 for one batch which is successively arranged on a belt conveyor 5 can be adjusted by changing the angle theta of a movable type baffle plate 4. The material 2-2 is charged through a hopper in the top part into the furnace by a swiveling chute 17 in the furnace. The grain size pattern of the material 2-2 with time is measured, for example, by an acoustic type grain size meter 15 for the raw material provided to a vertical chute and the deviation from the target grain size pattern in the predetermined measuring position is determined. The grain size pattern of the raw material for the succeeding batch is so adjusted to attain the target pattern from the information on such deviation.