| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method of obtaining rude zinc oxide powder as a Zn raw material by subjecting flue cinder in steel making to reduction roasting to recover rude zinc oxide dust, and thereafter, efficiently volatilizing and separating chlorine and fluorine from the rude zinc oxide dust, as a method of recovering rude zinc oxide powder from flue cinder. SOLUTION: Flue cinder in steel making is subjected to reduction roasting to recover rude zinc oxide dust containing, expressed in terms of metal, by mass, 40 to 60% zinc, 0.1 to 20% lead, 1.0 to 20% chlorine, and 0.1 to 10% fluorine, and, after that, the dust is charged to a rotary kiln, and zinc is volatilized to recover rude zinc oxide powder. The dust is roasted at 900 to 1,200 deg.C in an oxidizing atmosphere having an oxygen concentration of >=25%, so that the rude zinc oxide lead powder containing, expressed in terms of metal, by mass, >=55% zinc, >=5% lead, <=1.5% chlorine, and <=0.6% fluorine is obtained.</p> |
