| 摘要 |
PURPOSE: To produce a mixture of chromium carbide with iron carbide used as a chromium additive to special steel instead of high carbon ferrochromium at a low cost by finely crushing chrome ore and reacting a reducing gas containing a carbonaceous material with the crushed ore. CONSTITUTION: This production method of a mixture of chromium carbide with iron carbide is to crush chrome ore in <=1mm particle size, charge the crushed chrome ore on a perforated plate 4 (in a fluidized furnace) in the lower part of a reaction column 2, blow a mixture gas 8 having a molar ratio of 1 mole methane and 1.5-2 moles hydrogen, react the fine chrome ore 10 charged on the perforated plate 4 with the mixed gas during fluidizing, install a heating device 12 outside of the reaction column 2 through a refractory such as asbestos, keep inside of the reaction column at 650-950 deg.C, lead the upper part of the reaction column 2 to a water sealing device 16 through an exhaust pipe 14, adjust a gas blow in amount and pressure so that fluidized chrome ore 10 is not discharged outside. Thus, chromium carbide and iron carbide are obtained by direct carbonation. Vein stones, etc., which have not been carbonized are separated by a heavy liquid separation or a fusion separation. |
