Staged Washing of Solids CCD

The importance of washing solids after leaching and settling was demonstrated vividly in Illustration 7.8. The decantation tank in which the process is carried out is often referred to as a thickener, because the concentration of slurries by settling is carried out in similarly constructed tanks. Washing often entails some thickening so that the term is not misplaced. 

Not much has changed in the design of these units over the past century, primarily because they are eminently successful in accomplishing their mission. 

Mass Transfer and Separation Processes Principles and Applications 

CCD thickeners (a) schematic diagram and (b) units used in copper refining. (Olympic Dam, Southern Australia.) 

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