Multi-stage flash evaporator with recirculation of distilland

Claim 1

A MULTI-STAGE FLASH EVAPORATOR SYSTEM COMPRISING, MEANS FORMING A PLURALITY OF FLASH EVAPORATION CHAMBERS, FIRST HEAT EXCHANGE MEANS ASSOCIATED WITH EACH OF SAID EVAPORATION CHAMBERS FOR COOLING THE VAPORS FORMED THEREIN, PRIMARY MEANS FOR DIRECTING A STEAM OF INCOMING IMPURE WATER SUCCESSIVELY THROUGH EACH OF SAID FIRST HEAT EXCHANGE MEANS TO COOL SAID VAPORS AND PREHEATING SAID IMPURE WATER, SAID CHAMBERS INCLUDING A FIRST GROUP, AN INTERMEDIATE GROUP AND A LAST GROUP, SAID INTERMEDIATE GROUP INCLUDING AT LEAST FIRST, SECOND AND THIRD CHAMBERS OPERABLE AT SUCCESSIVELY LOWER TEMPERATURES, HEATING MEANS INTERPOSED BETWEEN THE FIRST HEAT EXCHANGE MEANS IN SAID FIRST GROUP AND THE CHAMBERS IN SAID FIRST GROUP FOR IMPARTING ADDITIONAL HEAT TO SAID IMPURE WATER, MEANS FOR DIRECTING THE HEATED IMPURE WATER FROM SAID HEATING MEANS TO SAID FIRST GROUP OF CHAMBERS FOR PARTIAL EVAPORATION, MEANS PROVIDING FLUID COMMUNICATION BETWEEN SAID RESPECTIVE CHAMBERS, WHEREBY THE HEATED IMPURE WATER UNDERGOIES SUCCESSIVE PARTIAL EVAPORATION IN EACH OF SAID CHAMBERS OF SAID GROUPS,