| 摘要 |
<p>PURPOSE:To separate and recover the iron powder contained dust and zinc with a high efficiency, by extracting wet dust slurry of blast furnace by sulfuric acid having a specific mol ratio afainst zinc and carrying out floatation separation after carrying out primary neutralization of extracting liquid by CaCo3 and next, carrying out secondary neutralization. CONSTITUTION:3-5 times of sufuric acid against zinc mol ratio, is added to the wet dust slurry of blast furance dividedly and the dust slurry is extracted. Solid is separated from liquid and extracting liquid and extracted residue are obtained after extraction and adhered soluble zinc is removed by washing the above residue. The above dust is reused for tlhe raw material of the blast furnace as zinc removed dust through sintering or pellet process. The extracting liquid and water washing liquid are mixed together and primary neutralization is carried out regulating pH at 4-5 by CaCo3. Moreover, floatation collector is added and iron is separated as scum by floation and then, the above scum is sent to the water treating process of extracted residue. Secondary neutralization of floatation tail solution is carried out by using alkli metal carbonate or bicarbonate and next, cake contained zinc having a high ZnO purity, is obtained by sedimentation separation concentration or direct filtration.</p> |
