He-3 recovery from natural helium by distillation
AssigneeAir Products and Chemicals, Inc.
InventorsJianguo Xu, David Ross Graham, Vipul S. Parekh
Life of this patent
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Abstract
A system and method for recovering helium-3 from helium. A distillation column having a top section that is smaller in diameter than a main section is provided. The column also includes an intermediate condenser that condenses vapor from the main section and above a helium feed stream. Reflux to the column can be provided by liquid helium-3 from a conduit or from an overhead condenser. In a preferred cycle, the distillation column is operated at a subatmospheric pressure, and in a temperature range between 2.3 K and 4.3 K.
Claims20
A method for recovering He-3 from helium, the method comprising:
- (a) introducing a feed stream comprising helium into a main section of a distillation column at a first location;
- (b) withdrawing an overhead stream comprising He-3-enriched helium from a top section of the distillation column, the main section of the distillation column being located below the top section, the main section having a first diameter that is greater than a second diameter of the top section;
- (c) withdrawing a bottom stream comprising He-3 depleted helium from a bottom portion of the main section of the column;
- and
- (d) condensing at least a first portion of a vapor stream by heat exchange with a first stream as the first stream passes through an intermediate condenser, wherein the at least a first portion of the vapor stream is drawn from a third location in the distillation column that is above the first location.
An apparatus for recovering He-3 from helium, the apparatus comprising:
- a distillation column having a main section and a top section, the main section being located below the top section and the main section having a first diameter that is greater than a second diameter of the top section;
- a feed conduit for introducing a feed stream comprising helium into the distillation column at a first location, the feed conduit being in fluid flow communication with a supply of helium;
- an overhead conduit for withdrawing a overhead stream comprising He-3-enriched helium from the top section of the distillation column;
- a bottom conduit for withdrawing a bottom stream comprising He-3-depleted helium from a bottom of the main section of the distillation column;
- and
- an intermediate condenser having an upstream side that is in fluid flow communication with an intermediate conduit that supplies a first stream to the upstream side of the intermediate condenser, the intermediate condenser being operationally configured to condense at least a first portion of a vapor stream that is drawn from a third location in the distillation column that is above the first location.
Dependencies are inferred from the claim text.