Apparatus and method for concentrating solutions

Claim 1

A METHOD FOR RECOVERING A FIRST SOLUTE FROM LIQUOR AND RECOVERING LIQUOR RELATIVELY CONCENTRATED WITH RESPECT TO A SECOND SOLUTE, COMPRISING: (A) INTRODUCING THE FEED LIQUID TO THE RECIRCULATION SYSTEM OF A FIRST EVAPORATOR CRYSTALLIZER EFFECT, AND HEATING SAID FEED LIQUOR BY INDIRECT HEAT EXCHANGE, AND PASSING THE RESULTING HEATED FEED LIQUOR TO SAID FIRST EFFECT, SAID FIRST EFFECT MAINTAINED UNDER A PRESSURE GREATER THAN ATMOSPHEREIC AND AT AN ELEVATED TEMPERATURE, WHEREBY VAPORIZATION OF THE LIQUOR AND CRYSTALLIZATION OF THE FIRST SOLUTE OCCURS RESULTING IN LIQUOR RELATIVELY MORE CONCENTRATED THAN SAID FEED LIQUOR WITH RESPECT TO THE SECOND SOLUTE; (B) PASSING STEAM THROUGH A THERMO-COMPRESSOR COMMUNICATING WITH SAID FIRST EFFECT TO ASPIRATE VAPORS GENERATED IN SAID FIRST EFFECT, AND RECIRCULATING A PORTION OF SAID VAPORS WITH SAID STEAM TO HEAT SAID FEED LIQUOR IN INDIRECT HEAT EXCHANGE IN SAIF FIRST MENTIONED HEAT EXCHANGER; (C) PASSING THE RESULTING CONCENTRATED LIQUOR FROM SAID FIRST EFFECT TO A SECOND EVAPORATOR CRYSTALLIZER EFFECT, SAID SECOND EFFECT MAINTAINED AT SUBATMOSPHERIC PRESSURE AND AT A TEMPERATURE RELATIVELY LOWER THAN SAID FIRST EFFECT AND HEATED AT LEAST IN PART FROM VAPORS FROM SAID FIRST EFFECT BY INDIRECT HEAT EXCHANGE, WHEREBY VAPORIZATION OF LIQUOR AND CRYSTALLIZATION OF THE FIRST SOLUTE OCCURS RESULTING IN FURTHER CONCENTRATION OF SAID LIQUOR WITH RESPECT TO THE SECOND SOLUTE; AND (D) SEPARATING THE CRYSTALS PRODUCED FROM SAID CONCENTRATED LIQUOR.

Claim 2

A METHOD FOR RECOVERING A FIRST SOLUTE FROM LIQUOR AND RECOVERING LIQUOR RELATIVELY CONCENTRATED WITH RESPECT TO A SECOND SOLUTE, COMPRISING: (A) INTRODUCING THE FEED LIQUID TO THE RECIRCULATION SYSTEM OF A FIRST EVAPORATOR CRYSTALLIZER EFFECT, AND HEATING SAID FEED LIQUOR BY INDIRECT HEAT EXCHANGE, AND PASSING THE RESULTING HEATED FEED LIQUOR TO SAID FIRST EFFECT, SAID FIRST EFFECT MAINTAINED UNDER A PRESSURE GREATER THAN ATMOSPHEREIC AND AT AN ELEVATED TEMPERATURE, WHEREBY VAPORIZATION OF THE LIQUOR AND CRYSTALLIZATION OF THE FIRST SOLUTE OCCURS RESULTING IN LIQUOR RELATIVELY MORE CONCENTRATED THAN SAID FEED LIQUOR WITH RESPECT TO THE SECOND SOLUTE; (B) PASSING STEAM THROUGH A THERMO-COMPRESSOR COMMUNICATING WITH SAID FIRST EFFECT TO ASPIRATE VAPORS GENERATED IN SAID FIRST EFFECT, AND RECIRCULATING A PORTION OF SAID VAPORS WITH SAID STEAM TO HEAT SAID FEED LIQUOR IN INDIRECT HEAT EXCHANGE IN SAIF FIRST MENTIONED HEAT EXCHANGER; (C) PASSING THE RESULTING CONCENTRATED LIQUOR FROM SAID FIRST EFFECT TO A SECOND EVAPORATOR CRYSTALLIZER EFFECT, SAID SECOND EFFECT MAINTAINED AT SUBATMOSPHERIC PRESSURE AND AT A TEMPERATURE RELATIVELY LOWER THAN SAID FIRST EFFECT AND HEATED AT LEAST IN PART FROM VAPORS FROM SAID FIRST EFFECT BY INDIRECT HEAT EXCHANGE, WHEREBY VAPORIZATION OF LIQUOR AND CRYSTALLIZATION OF THE FIRST SOLUTE OCCURS RESULTING IN FURTHER CONCENTRATION OF SAID LIQUOR WITH RESPECT TO THE SECOND SOLUTE; AND (D) SEPARATING THE CRYSTALS PRODUCED FROM SAID CONCENTRATED LIQUOR.