| 摘要 |
<p>PROBLEM TO BE SOLVED: To always suitably treat without fear of oxidizing a pellet by introducing the air of a suitable amount without excess and without insufficiency to a heating zone, and burning unburned gas generated in a reducing zone in the heating zone, thereby improving a fuel material unit and contributing to an energy conservation. SOLUTION: Pellets 1 made by mixing a metal oxide and a reducing agent and granulating the mixture are charged in a rotary hearth furnace 2. The pellets 1 are heated to a high temperature by burners 21, 42 provided in the zones 20, 40 of the furnace 2 to reduce the metal and to recover it. The air is introduced to the zone 20 according to measured concentrations of O2 or CO of the gas in the furnace of the zone 20, and unburned gas generated in the reducing zone is burned in the heating zone.</p> |
