Helical multistage flash distillation unit

Claim 1

A multistage flash distillation comprising: a. a continuous, downwardly spiralling, substantially enclosed passage winding around an elongated central core: b. a plurality of transverse partitions in said passage depending downward from the roof of said passage and terminating above the floor of said passage, and dividing said passage into a series of flash evaporation stages; wherein said partitions are spaced progressively closer to one another from the uppermost to the lowermost end of said end of said spiral passage so that there is a progressive reduction in stage size from said uppermost to said lowermost end; c. a weir adjacent to and downstream from each partition whereby liquid flows under each partition and over each weir and thereby provides a vapor seal between stages; d. means to maintain said stages under progressively lower flashing pressure from said uppermost to said lowermost end of said passage; e. means to feed superheated distilland to said uppermost end of said passage so that it may flow downwardly through said series of stages, and so that it may flash as it enters each of said stages; f. a condensing chamber in said central core; g. tube means extending through said chamber from the bottom to the top thereof; h. a plurality of horizontal partitions in said chamber dividing it into a plurality of condensing stages one above the other; i. means to pass a condensing medium upwardly through said tube means; and j. orifice means in said evaporator passage connecting each of said flash evaporation stages with an adjacent one of said condenser stages so that vapor evolved in each of said flash evaporation stages can pass into an adjacent condenser stage and condense upon said tube means.