| 摘要 |
<p>PURPOSE:To enable economical preliminary reduction of powder and granular ore stably in operation by providing a preheater for the powder and granular ore above a fluidized bed preliminary reduction furnace of a melt reduction device and passing the waste gas from the preliminary reduction furnace through the preheater. CONSTITUTION:The powder and granular ore 20 supplied at a constant rate from a raw material hopper 19 into a preheater 12 by a supply device 18 is heated by the waste gas from a preliminary reduction furnace 2 through a waste gas introducing pipeline 14 while it descends in the preheater 12. On the other hand, the waste gas having the decreased temp. is discharged through a discharge part 16. The ore arriving at the bottom end of the preheater 12 is supplied by its own weight into the furnace 2. A part or the whole of the high temp. reducing gas discharged from a melt reduction furnace 1 is introduced through a waste gas pipeline 7 into the furnace and if necessary a powder and granular flux, solid reducing agent and reducing gas are supplied through a supply pipeline 9 thereto according to need to reduce preliminarily the ore 20. The waste gas is discharged from a discharge part 16 and is blown together with the high temp. air in a tuyere blast branch 4 into the furnace 1.</p> |
