The lye coming from the filter press should be clear and have a slight yellowish cast.
Having obtained this clear solution, agitation is stopped, and the contents of the tank passed through a filter press.
Such, in brief, is the manner of using this filter press for chemical works' purposes.
As to the filter press cake, this may be best thrown away in a small factory.
This filter press is not in use anywhere for dealing with large quantities of water in connection with a town water supply.
Another application of the filter press is in the Porter-Clark process of softening water, which is shown in operation.