| 摘要 |
<p>PURPOSE:To enable the removal of zinc from high zinc dust and recover a large part of various kinds of dusts as raw material being available in an iron works by using a wet type dezinc method which can do without preparing a neutralizer separately, at the time of comprehensively treating the various kinds of dusts produced in the iron works. CONSTITUTION:The zinc-containing dust kinds produced in the iron-making integral process of iron-making, steelmaking and rolling are separately collected or wet-classified to separate these dusts into low zinc dust and high zinc dust. After leaching the zinc by bringing acid into contact with the high zinc dust, the solid-liquid mixture is separated into the low zinc dust and the leach liquor, and the leach liquor is neutralized by using alkaline waste water produced at the time of executing the separate-collection or wet classification to precipitate zinc hydroxide. Then the low zinc dust is utilized as the raw material for producing sintered ore and the zinc hydroxide is utilized as the raw material for refining. Further, in the case of containing much iron dissolved in the leach liquor, before precipitating the zinc hydroxide by the neutralization, the iron content is precipitated as the iron hydroxide and recovered beforehand.</p> |
