| 摘要 |
<p>A process for the recovery of selected metal values from silica containing sludges including incineration of the sludge to degrade organic components, followed by acid leaching of the ash, followed by hydrometallurgical recovery of metal values from the remaining solid and liquid residues, wherein prior to incineration of the sludge a quantity of soluble sodium and/or potassium salts are mixed with the sludge, the quantity being in excess by weight of the silica content of the sludge, and then the incineration step is carried out on this mixture so that silicates which form during such incineration are predominantly soluble in water and in the leaching acid, whereby to avoid the occluding of metal values in insoluble glass matrices which would not be attacked by subsequent acid leaching and hydrometallurgical steps.</p> |
