METHOD FOR TREATING METAL OXIDE

PROBLEM TO BE SOLVED: To provide a treating method which is improved so that the amount of thermal energy necessary for smelting reduction of a metal oxide can be decreased by preheating the metal oxide by means of reduction exhaust gas used in the smelting reduction of the metal oxide. SOLUTION: Treatment equipment used in this method is equipped with: a swirl combustor constituted of a cylindrical vessel having a separation chamber at the bottom and also two reducing-gas-feeding holes; a rotary kiln connected to the upper part of the separation chamber of the swirl combustor; and a cyclone connected to the top of the cylindrical vessel. The metal oxide is introduced into the rotary kiln and preheated, and the resultant mixed fluid of the metal oxide and reduction exhaust gas is introduced into the cyclone to undergo separation into the metal oxide and the reduction exhaust gas. The separated metal oxide is introduced into the cylindrical vessel to undergo smelting reduction by means of high-temperature reducing gas. Then the resultant molten metal is separated from slag in the separation chamber at the bottom and recovered, and the reduction exhaust gas is fed to the rotary kiln. COPYRIGHT: (C)2006,JPO&NCIPI