Inhibiting scale formation in fresh water recovery

Claim 1

A METHOD OF RECOVERING POTABLE WATER FROM SEA WATER CONTAINING NON-CONDENSABLE GASES AND HAVING CARBONATE AND HYDROXIDE SCALE-FORMING CHARACTERISTICS WHILE INHIBITING SCALE FORMATION ON HEAT EXCHANGER SURFACES AT ELEVATED TEMPERATURES IN A FLASH EVAPORATION SYSTEM COMPRISING A PLURALITY OF FLASH EVAPORATOR STAGES, THE COMBINATION OF STEPS COMPRISING SUBJECTING HEATED SEA WATER CHARACTERIZED BY THE PRESENCE OF BICARBONATE IONS TO A FLASH EVAPORATION AND RECOVERY CYCLE IN A FLASH EVAPORATOR SYSTEM AT A TEMPERATURE AT WHICH AT LEAST A PORTION OF THE BICARBONATE IONS DECOMPOSES TO FORM CARBON DIOXIDE WHICH WHEN IT LEAVES THE WATER TENDS TO CAUSE AN INCREASE IN PH CONDUCIVE TO SCALE FORMATION, FORMING CONDENSATE AND REMOVING IT FROM SAID SYSTEM, COLLECTING THE CARBON DIOXIDE AND OTHER NON-CONDENSABLE GASES RELEASED DURING SAID FLASH EVAPORATION, INTRODUCING SAID COLLECTED CARBON DIOXIDE INTO SEA WATER PRIOR TO EVAPORATION IN SAID FLASH EVAPORATOR SYSTEM WHILE VENTING NON-CONDENSABLE GASES, SAID CARBON DIOXIDE BEING INTRODUCED INTO SAID SEA WATER BEFORE SAID SEA WATER PRIOR TO EVAPORATION IS PREHEATED UP TO 150*F., CONDUCTING SAID SEA WATER CONTAINING THE ADDED CARBON DIOXIDE TO AN EVAPORATOR PREHEATER IN SAID SYSTEM, HEATING SAID SEA WATER TO AN ELEVATED TEMPERATURE EXCEEDING 170* F. WHILE MAINTAINING SAID SEA WATER DURING HEATING AT A PRESSURE GREATER THAN THE PRESSURE AT WHICH SAID SEA WATER BOILS AT SAID ELEVATED TEMPERATURE WHEREBY TO MAINTAIN CARBON DIOXIDE DISSOLVED IN SAID SEA WATER AND INHIBIT SCALE FORMATION IN SAID EVAPORATOR PREHEATER, AND THEN SUBJECTING SAID SEA WATER TO FLASH EVAPORATION.

Claim 2

A METHOD OF RECOVERING POTABLE WATER FROM SEA WATER CONTAINING NON-CONDENSABLE GASES AND HAVING CARBONATE AND HYDROXIDE SCALE-FORMING CHARACTERISTICS WHILE INHIBITING SCALE FORMATION ON HEAT EXCHANGER SURFACES AT ELEVATED TEMPERATURES IN A FLASH EVAPORATION SYSTEM COMPRISING A PLURALITY OF FLASH EVAPORATOR STAGES, THE COMBINATION OF STEPS COMPRISING SUBJECTING HEATED SEA WATER CHARACTERIZED BY THE PRESENCE OF BICARBONATE IONS TO A FLASH EVAPORATION AND RECOVERY CYCLE IN A FLASH EVAPORATOR SYSTEM AT A TEMPERATURE AT WHICH AT LEAST A PORTION OF THE BICARBONATE IONS DECOMPOSES TO FORM CARBON DIOXIDE WHICH WHEN IT LEAVES THE WATER TENDS TO CAUSE AN INCREASE IN PH CONDUCIVE TO SCALE FORMATION, FORMING CONDENSATE AND REMOVING IT FROM SAID SYSTEM, COLLECTING THE CARBON DIOXIDE AND OTHER NON-CONDENSABLE GASES RELEASED DURING SAID FLASH EVAPORATION, INTRODUCING SAID COLLECTED CARBON DIOXIDE INTO SEA WATER PRIOR TO EVAPORATION IN SAID FLASH EVAPORATOR SYSTEM WHILE VENTING NON-CONDENSABLE GASES, SAID CARBON DIOXIDE BEING INTRODUCED INTO SAID SEA WATER BEFORE SAID SEA WATER PRIOR TO EVAPORATION IS PREHEATED UP TO 150*F., CONDUCTING SAID SEA WATER CONTAINING THE ADDED CARBON DIOXIDE TO AN EVAPORATOR PREHEATER IN SAID SYSTEM, HEATING SAID SEA WATER TO AN ELEVATED TEMPERATURE EXCEEDING 170* F. WHILE MAINTAINING SAID SEA WATER DURING HEATING AT A PRESSURE GREATER THAN THE PRESSURE AT WHICH SAID SEA WATER BOILS AT SAID ELEVATED TEMPERATURE WHEREBY TO MAINTAIN CARBON DIOXIDE DISSOLVED IN SAID SEA WATER AND INHIBIT SCALE FORMATION IN SAID EVAPORATOR PREHEATER, AND THEN SUBJECTING SAID SEA WATER TO FLASH EVAPORATION.