Process for recovering a desired soluble salt from a solid mixture containing same

Claim 1

A PROCESS FOR SEPARATING A DESIRED COMPONENT SALT FROM ADMIXTURE IN A WATER-SOLUBLE ORE, WHICH COMPRISES THE STEPS OF MIXING THE FINELY DIVIDED ORE WITH A SOLUTION SATURATED WITH THE COMPONENT SALTS COMPRISING SAID ORE, REMOVING AN UNDESIRED COMPONENT SALT FROM SAID ORE BY FLOTATION WITH THE DESIRED SALT FORMED AS A CONCENTRATE, SEPARATING THE SAID OTHER SALT FROM SOLUTIN ENTRAINED THEREWITH AFTER ITS REMOVAL FROM THE FLOTATION STAGE, SEPARATING THE DESIRED SALT FROM THE SATURATED SOLUTION IN THE CONCENTRATE, WASHING AT LEAST ONE OF THE COMPONENT SALTS SO SEPARATED WITH WATER AND COMBINING SAID WASH WATER WITH THE SOLUTION PREVIOUSLY SEPARATED FROM AT LEAST ONE OF THE SALTS, EVAPORATING A PORTION OF THE LIQUID MIXTURE SO FORMED TO A CONCENTRATION SUCH THAT AT A DETERMINED TEMPERATURE OF EVAPORATION AN AMOUNT OF WATER IS REMOVED WHICH IS SUBSTANTIALLY EQUIVALENT TO THE AMOUNT OF WATER USED IN SAID WASHING OPERATION, THEREBY FORMING A SALT SLUDGE WHILE PREVENTING CRYSTALLIZATION AND PRECIPITATION OF THE DESIRED COMPONENT SALT FROM SOLUTION, RETURNING SAID SLUDGE TO ONE OF SAID PRIOR SEPARATION STAGES TO SEPARATE ASSOCIATED SOLUTION FROM ITS SOLIDS CONTENT, AND RECYCLING THE SOLUTION REMAINING AFTER SAID EVAPORATION FOR MIXING THE ORE PRIOR TO FLOTATION, SO THAT ANY CRYSTALLIZATION OF THE DESIRED COMPONENT SALT WILL OCCUR NOT LATER THAN DISCHARGE FROM THE FLOTATION STAGES AND WILL THUS ACCOMPANY THE CONCENTRATES.