Apparatus for purifying a vaporizable liquid

Claim 1

Apparatus for purifying impure vaporizable liquid which contains dissolved inorganic solids, including in combination: (a) a closed vessel comprising (1) a vapor producing lower section having a liquid inlet thereat, means connected to said inlet from an external source for introducing said impure vaporizable liquid thereinto, means for heating said impure liquid therein and producing vapor therefrom, and means for removing accumulated inorganic solids therefrom, (2) a vapor condensing upper section including therein means for cooling and condensing said vapor to form condensate of said vaporizable liquid, and (3) a vapor backwashing intermediate section in communication with said lower section and said upper section and comprising means for passing vapor from said vapor producing section upwardly through said intermediate section to said vapor condensing section and for passing condensate from said vapor condensing section downwardly in countercurrent contact with said upwardly passing vapor and to said vapor producing section, said intermediate section also comprising at a location more proximate to said upper section than to said lower section vapor outlet and withdrawal means for withdrawing a portion of said upwardly passing vapor which at said location has been purified by traversing a major part of said intermediate section in contact with backwashing condensate which has been formed from purified vapor in said upper section, (b) said vapor outlet and withdrawal means comprising a conduit connected to said intermediate section at said more proximate location and means for cooling said conduit for condensing said withdrawn purified vapor therein, and (c) means for collecting condensate of said vaporizable liquid formed from said purified vapor in said conduit.