Integrated process and apparatus for recovery of helium rich streams
AssigneePraxair Technology, Inc.
InventorsMinish M. Shah, Joseph M. Schwartz, Khushnuma Koita, Michael J. Dray
Life of this patent
Estimating the term…
Abstract
The present invention relates a process and apparatus that recovers a helium rich stream from a mixed gas having low concentrations of helium therein. More specifically, the invention relates to an integrated process and apparatus for treating a mixed feed gas from an operating process that produces a liquid product from natural gas containing helium, such as processes that produce ammonia, methanol, or liquid hydrocarbons.
Claims25
An integrated process for recovery of a helium rich stream and a hydrogen rich stream from a feed stream containing 10-80 volume percent hydrogen, 0.1-5.0 volume percent helium, and the balance being higher boiling components, comprising:
- (a) routing the pressurized feed stream to a cryogenic separation unit wherein the majority of the higher boiling components are separated and removed from the feed stream;
- (b) heating a stream containing helium removed from the cryogenic separation unit and routing the heated stream to at least one hydrogen transport membrane where the heated stream is separated into a hydrogen rich permeate stream, and a retentate stream depleted of hydrogen;
- (c) routing the retentate stream depleted of hydrogen to at least one oxidation unit and reacting it with an oxidant to remove substantially all the remaining hydrogen in the retentate to produce a helium containing stream, wherein the helium concentration ranges from about 5-40 volume percent and the balance being higher boiling components;
- (d) routing the helium containing stream to a phase separator and sequentially a dryer wherein most of the water is removed;
- and
- (e) routing the dried helium containing stream to the same or a different cryogenic separation unit where the majority of remaining higher-boiling components are removed and a helium rich product stream having about 80% or higher helium content by volume is obtained.
The integrated process for recovery of a helium rich stream from a feed stream containing 10-80 volume percent of hydrogen, 0.1-5.0 volume percent helium, and the balance being higher boiling components, comprising:
- (a) routing the pressurized feed stream to a cryogenic separation unit wherein the majority of the higher boiling components are separated and removed from the feed stream;
- (b) heating the feed stream removed from the cryogenic separation unit and routing the heated feed stream to at least one hydrogen transport membrane where the feed stream is separated into a hydrogen rich permeate stream, and a retentate stream depleted of hydrogen;
- (c) routing the retentate stream depleted of hydrogen to at least one oxidation unit to remove substantially all the hydrogen remaining in the retentate to produce a helium containing stream, wherein the helium concentration ranges from about 5-40 volume percent and the balance being higher boiling components;
- (d) routing the helium containing stream to a phase separator and sequentially a dryer wherein most of the water is removed;
- and
- (e) further processing the helium containing stream of step (d) in one or more polymeric membrane stages, wherein the permeate is recovered as helium rich product stream having about 80% or higher helium content by volume.
The integrated process of 19, where the permeate stream having at least about 30% helium content is further separated in a third polymeric membrane stage into a third retentate stream which can be recycled to the first polymeric membrane and a third permeate stream recovered as helium rich product having about 80% or higher helium content by volume.
Dependencies are inferred from the claim text.