| 摘要 |
PURPOSE:To manufacture inexpensively a high-chrome alloy such as ferrochrome by a melting and reducing method without dependance on an electric power by supplying a part of carbonaceous material from a top-blown lance in melting and reducing raw materials contg. chromeoxide in a top and bottom blown converter-type reactor. CONSTITUTION:Melting and reducing are progressed by supplying respectively half- reduced chrome pellets 9 and lumps of carbonaceous material 10 from a rotary kiln 2 and fluxes such as lime stone or the like and a part of charbonaceous materials 10 from a hopper 6 at the upper part of a furnace to a remaining molten alloy 7 under top-blowing of oxygen. After the slag quantity exceeds the limited value, remaining pellets 9 are supplied and further the prescribed quantity of pellets are thrown. Until the chrome % in the discharged slag is lowered to a prescribed value, carbonaceous powder is supplied from the top-blown lance 4. In the first half of the case, oxygen blowing from the lance 4 is carried out, however if the desired chrome % in the discharged slag is low, the oxygen blowing can be stopped in the latter half. Inexpensive coke powder or the like can be used as the carbonaceous powder, however, if a part thereof is substituted by earthy graphite, the abrasion of a powder transporting pipe is suppressed by the lubricating effect. |
