Method for operating multiple effect evaporators

Abstract From the Canadian patent

Disclosed is an improved method of recovering a salt having a solubility which increases with increasing temperatures from a multiple salt aqueous solution also containing a salt having a solubility which increases less with increasing temperatures than the solubility of the salt to be recovered. The solution is subjected to multiple effect evaporation having a plurality of evaporator effects operating at progressively higher temperatures. In the improved method a means is provided whereby the mother liquor effluent overflow from the hottest evaporator effect is saturated with the salt to be recovered. Additionally solution being concentrated in other effects having at least one preceding …