US PATENT SUBCLASS 203 / 75
.~.~.~ And return of distillation product to a previous distillation zone

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


203 /   HD   DISTILLATION: PROCESSES, SEPARATORY

71  DF  PLURAL DISTILLATIONS PERFORMED ON SAME MATERIAL {5}
73  DF  .~ One a distillation under positive pressure or vacuum {4}
74  DF  .~.~ Distillation of initial distillate {3}
75.~.~.~ And return of distillation product to a previous distillation zone

DEFINITION

Classification: 203/75

(under subclass 74) Processes in which a product from a later distillation operation is returned in terms of the process to a distillation zone prior to the distillation zone in which the product was produced.

(1) Note. The prior distillation zone must be in the series of distillation operations which produced the product being returned.

(2) Note. The product returned may be all or a part of a product of a second or subsequent distillation operation in a series.

SEE OR SEARCH CLASS

165, Heat Exchange,

104.21+, for apparatus in which liquid is vaporized at one zone, condensed at another and the condensate is returned to the first zone. 196, Mineral Oils: Apparatus,

99, for mineral oil distilling apparatus including the combination of a vaporizer, condensing means with means for returning a part or all of the condensate to the vaporizer.

208, Mineral Oils: Processes and Products,

355, for a process of subjecting mineral oil to at least two distillation operations in which either vapors, condensate, and/or residue from a later distillation zone is returned to an earlier distillation zone.