Abstract
In smelting reduction, it is desirable to use fine ore without agglomeration. In order to find the proper condition for fine ore addition to bath without injection, experiments involving a cold model and smelting reduction were performed.
(1) In the cold model test, a stream of fine materials (iron ore or coke) was passed into the gas of the counter flow. The rate of carry-over (g/s) depended on the surface area of the stream. The ratio of carry-over (%) decreased to less than 5% when the rate of supply was increased. Therefore, it is possible to decrease the ratio of carry-over during addition by decreasing the specific surface area of the stream, independent of the sort and size of fine materials.
(2) When fine ore was added through a hole in the shoulder of a 100 t smelting reduction furnace, the ratio of carry-over was negligible when compared with the amount of dust originating from molten metal. So, it has been confirmed that top addition of fine ore without agglomeration is practical.
On the other hand, in the case of a fine carbonaceous material, the ratio of carry-over was high, even with an appropriate method of adding the fine ore.
