Mass balance calculations for the solids

If the solids to be washed are much coarser than the cut sizes in all stages of the washing train, complete separation in each stage may be assumed and the mass balance calculations become trivial (i.e. each underflow stream carries the same mass flow rate of the solids, equal to the feed rate, and all overflows are free of solids). 

On the other hand, if some solids do escape because the stage cut size is not low enough, mass balance calculations may have to be performed when designing or troubleshooting the system. The difficulty is that, from the particle separation standpoint, not all stages have the same effect even when 

As can be seen from the above, mass balance calculations for the solids are needed in all non-trivial cases of equipment design, modeUing and 

1 A short-cut method for system particle separation efficiency calculations 

If the concentrations and particle size distributions of the solids within the washing train itself do not have to be known then the train can be considered as a single separator and its efficiency can be calculated from that of the individual stages within it. The system efficiency thus obtained can then be used in simple one-pass predictions of particle losses to overflow and other overall separation performances of the train. This allows direct comparisons of alternative systems, as shown in the worked example below. 

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