摘要 |
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 the incineration step is carried out at a temperature below the slagging temperature of silicates, whereby to avoid the occluding of metal values in glass matrices which are not attacked by subsequent acid leaching and hydrometallurgical steps. |