| 摘要 |
<p>PURPOSE:To evaporate and liberate deposited Zn and to use scrap galvanized steel sheet as an iron source by heating the scrap in a gaseous atmosphere of specified composition. CONSTITUTION:Solid carbon such as coke or gaseous hydrocarbons are introduced from a feeder 9 into an externally heated rotary kiln 1 provided with a burner 3 as the external heating means 2, and an oxidizing gas such as air and CO2 is simultaneously introduced from its feeder 10 and heated by the means 2 to form a reducing gas atmosphere satisfying 0.01<CO2/CO<1 by the reaction of the solid carbon or gaseous hydrocarbons with the oxidizing gas such as air. The scrap galvanized steel sheet in a closed vessel 8 is supplied into the kiln 1 by a feeder 7 and heated to 800-1200 deg.C. The Zn in the scrap is evaporated, liberated, cooled by a waste gas treating device 13, solidified and recovered, and scrap iron free of Zn and usable as the Fe material is recovered in a vessel 12.</p> |
