1996 Volume 82 Issue 9 Pages 725-730
It was reported that the reduction rate constant of iron are increased with increasing of the amount of slag in the smelting reduction with a thick slag layer. However, its mechanism was not clear.
In this study, distributions of metal droplets and carbonaceous materials in the slag layer were investigated with a 100t converter and the mechanism of reduction of iron are was discussed. The obtained results were as follows:
(1) Considered from the distributions above, 44% of iron oxide was reduced at the metal surface in the lower 30% of the slag layer, 6% of theat was reduced at the metal surface in the upper 70% of the slag layer and 50% of that was reduced at the surface of the carbonaceous materials in the slag.
(2) For achieving high productivity keeping high post-combustion ratio, low dust formation and a stable operation without slag foaming, the following methods are useful.
(i) keeping a large amount of slag.
(ii) keeping a large amount of carbonaceous materials in the slag.
(iii)controlling the bottom stirring to surpress the amount of metal droplets in the upper 70% of slag layer.
