Multiple effect evaporator of the switching type

Claim 1

A CHANNEL SWITCHING MULTIPLE EFFECT EVAPORATOR, COMPRISING N INDIRECT HEAT EXCHANGERS, (N-1) VAPOR BODIES, N BEING A POSITIVE WHOLE NUMBER, EACH HEAT EXCHANGER HAVING SEPARATED FIRST AND SECOND CHANNELS IN HEAT EXCHANGING RELATIONSHIP TO EACH OTHER, FIRST CONDUIT MEANS INCLUDING A RESPECTIVE ONE OF THE VAPOR BODIES CONNECTING THE SECOND AND FIRST CHANNELS OF SUCCESSIVE HEAT EXCHANGERS, MEANS TO REMOVAL LIQUID PRODUCT FROM THE LOWER END OF THE VAPOR BODIES, A SECOND CONDUIT MEANS HAVING VALVES THEREIN SELECTIVELY OPERABLE, (1) IN A FIRST CONDITION TO DIRECT LIQUOR TO BE EVAPORATED INTO THE SECOND CHANNEL OF THE FIRST AND ALL SUBSEQUENT HEAT EXCHANGERS EXCEPT THE LAST HEAT EXCHANGER, AND UPON CHANNEL SWITCHING, (2) IN A SECOND CONDITION, TO DIRECT LIQUOR TO BE EVAPORATED INTO THE FIRST CHANNELS OF THE LAST AND ALL PRIOR HEAT EXCHANGERS EXCEPT THE FIRST HEAT EXCHANGER, THE TERMS "FIRST," "SECOND," AND "LAST" REFERRING TO POSITION ONLY, CONSIDERED FROM LEFT TO RIGHT, A THIRD CONDUIT MEANS HAVING VALVES THEREIN OPERABLE WHEN THE EVAPORATOR IS OPERATING IN SAID FIRST CONDITION TO INTRODUCE HEATING STEM INTO THE FIRST CHANNEL OF THE FIRST HEAT EXCHANGER AND TO EXHAUST CONDENSATE THEREFROM, AND TO INTRODUCE WATER INTO THE SECOND CHANNEL OF THE LAST HEAT EXCHANGER AND TO EXHAUST SUCH WATER IN HEATED CONDITION THEREFROM, AND A FOURTH CONDUIT MEANS HAVING VALVES THEREIN OPERABLE WHEN THE EVAPORATOR IS OPERATING IN SAID SECOND CHANNEL OF THE LAST HEAT EXCHANGER AND TO EXHAUST CONDENSATE THEREFROM, AND TO INTRODUCE WATER INTO THE FIRST CHANNEL OF THE FIRST HEAT EXCHANGER AND TO EXHAUST SUCH WATER IN HEATED CONDITION THEREFROM.