Patent US5302189A successfully refreshed from Google Patents.
US5302189A
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Membrane nitrogen gas generator with improved flexibility
Assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Filing: 1992-08-26
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Granted: 1994-04-12
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Expires: 2012-08-26
Abstract
Abstract A membrane nitrogen gas generator, containing a feed stream compressor, one or more filtering membranes, each having a permeate side and a non-permeate side, in fluid connection with and downstream of the feed stream compressor, and one or more product storage containers capable of storing a product having a higher purity than is required by customer demand, and which generator is capable of generating an increased flow rate during periods of high demand.
Inventors
- 👤 Christian Barbe
- 👤 Jean-Renaud Brugerolle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:52
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/22; B01D2317/00; B01D2317/02; B01D2317/04
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
125 words
A method of generating nitrogen with improved flexibility, which comprises: (a) generating a first nitrogen gas from a membrane nitrogen generator, said gas being of higher purity than required by customer demand during periods of low generator demand, (b) storing said first nitrogen gas having higher purity in one or more product storage means, and (c) mixing said stored first nitrogen gas from said one or more storage means with a second nitrogen gas having a lower purity than said stored first nitrogen gas, said lower purity gas being produced during periods of high generator demand, to produce an increased flow rate of final product which has a purity higher than that which would be produced by the generator alone at the same flow rate.
Claim 2
Independent Claim
125 words
A method of generating nitrogen with improved flexibility, which comprises: (a) generating a first nitrogen gas from a membrane nitrogen generator, said gas being of higher purity than required by customer demand during periods of low generator demand, (b) storing said first nitrogen gas having higher purity in one or more product storage means, and (c) mixing said stored first nitrogen gas from said one or more storage means with a second nitrogen gas having a lower purity than said stored first nitrogen gas, said lower purity gas being produced during periods of high generator demand, to produce an increased flow rate of final product which has a purity higher than that which would be produced by the generator alone at the same flow rate.
Claim 3
Dependent Claim
12 words
The method of claim 1, wherein one product storage means is used.
Claim 4
Dependent Claim
16 words
The method of claim 2, wherein said product storage means is a gaseous product storage means.
Claim 5
Dependent Claim
44 words
The method of claim 1, wherein said higher purity of said first nitrogen gas and said final product nitrogen gas comprises an oxygen content in said first nitrogen gas and said final product nitrogen gas which is lower than an acceptable oxygen content thereof.
Claim 6
Dependent Claim
30 words
The method of claim 4, wherein said lower oxygen content equals oxygen content required by a customer divided by a factor n, where n is from about 1.2 to 20.
Claim 7
Dependent Claim
19 words
The method of claim 1, wherein said low generator demand comprises about 80 units or less of generator output.
Claim 8
Dependent Claim
19 words
The method of claim 1, wherein said high generator demand comprises about 120 units or more of generator output.
Claim 9
Dependent Claim
50 words
The method of claim 1, wherein said lower purity gas produced during periods of high generator demand is produced by boosting generator production to a value of about 1.1 to 5 times nominal production by increasing the oxygen content in the product by a factor of about 2 to 8.
Claim 10
Dependent Claim
27 words
The method of claim 1, wherein said membrane nitrogen generator comprises a membrane system, which comprises one or more membrane modules arranged in parallel or in series.
Claim 11
Dependent Claim
22 words
The method of claim 9, wherein the one or more membrane modules comprise hollow fiber, spiral wound, or pleated flat sheet membranes.
Claim 12
Dependent Claim
29 words
The method of claim 10, wherein said membranes are made of a material selected from the group consisting of cellulose acetate, cellulose acetate butyrate, polyamides, polyimides, polysulfones and polystyrenes.
Claim 13
Dependent Claim
12 words
The method of claim 11, wherein said membrane is made of polyimide.
Claim 14
Dependent Claim
18 words
The method of claim 10, wherein said hollow fiber membranes are homogeneous, symmetric, asymmetric or composite fiber membranes.
Claim 15
Dependent Claim
44 words
The method of claim 13, wherein said hollow fiber membranes are asymmetric membranes and have a dense discriminating region which separates one or more fluids from one or more other fluids based upon differences in solubility and diffusivity of the fluids in the region.
Claim 16
Dependent Claim
27 words
The method of claim 13, wherein said hollow fiber membranes are made of a material selected from the group consisting of polyestercarbonates, polysulfones, polyethersulfones, polyimides and polycarbonates.
Claim 17
Independent Claim
114 words
A method for increasing generator flow rate of nitrogen during a period of increased demand, which comprises: (a) producing a first nitrogen gas of higher purity than is required by customer demand during period of low demand, and storing the product in one or more product storage means, (b) producing a second nitrogen gas of a lower purity than is required by customer demand during periods of high demand, and (c) mixing said first and second nitrogen gas products during said period of increased demand to produce an increased flow rate of final product which has a purity higher than that which would be produced by the generator alone at the same flow rate.
Claim 18
Independent Claim
114 words
A method for increasing generator flow rate of nitrogen during a period of increased demand, which comprises: (a) producing a first nitrogen gas of higher purity than is required by customer demand during period of low demand, and storing the product in one or more product storage means, (b) producing a second nitrogen gas of a lower purity than is required by customer demand during periods of high demand, and (c) mixing said first and second nitrogen gas products during said period of increased demand to produce an increased flow rate of final product which has a purity higher than that which would be produced by the generator alone at the same flow rate.
Claim 19
Dependent Claim
12 words
The method of claim 16, wherein one product storage means is used.
Claim 20
Dependent Claim
16 words
The method of claim 17, wherein the product storage means is a gaseous product storage means.
Claim 21
Dependent Claim
19 words
The method of claim 17, wherein said high generator demand comprises about 120 units or more of generator output.
Claim 22
Dependent Claim
19 words
The method of claim 16, wherein the higher purity comprises an oxygen content lower than an acceptable oxygen content.
Claim 23
Dependent Claim
27 words
The method of claim 20, wherein said lower oxygen content equals required oxygen content divided by a factor n, where n is from about 1.2 to 20.
Claim 24
Dependent Claim
19 words
The method of claim 16, wherein said low generator demand comprises about 80 units or less of generator output.
Claim 25
Dependent Claim
50 words
The method of claim 16, wherein said lower purity gas produced during periods of high generator demand is produced by boosting generator production to a value of about 1.1 to 5 times nominal production by increasing the oxygen content in the product by a factor of about 2 to 8.
Claim 26
Dependent Claim
26 words
The method of claim 16, wherein said nitrogen generator comprises a membrane system, which comprises one or more membrane modules arranged in parallel or in series.
Claim 27
Dependent Claim
22 words
The method of claim 24, wherein the one or more membrane modules comprise hollow fiber, spiral wound, or pleated flat sheet membranes.
Claim 28
Dependent Claim
29 words
The method of claim 25, wherein said membranes are made of a material selected from the group consisting of cellulose acetate, cellulose acetate butyrate, polyamides, polyimides, polysulfones and polystyrenes.
Claim 29
Dependent Claim
12 words
The method of claim 26, wherein said membrane is made of polyimide.
Claim 30
Dependent Claim
16 words
The method of claim 25, wherein said hollow fiber membranes are homogeneous, symmetric, asymmetric or composite.
Claim 31
Dependent Claim
44 words
The method of claim 28, wherein said hollow fiber membranes are asymmetric membranes and have a dense discriminating region which separates one or more fluids from one or more other fluids based upon differences in solubility and diffusivity of the fluids in the region.
Claim 32
Dependent Claim
28 words
The method of claim 28, wherein said hollow fiber membranes are made of a material selected from the group consisting of polyestercarbonates, polysulfones, polyether sulfones, polyimides and polycarbonates.
References Cited (Backward Citations)
US3735558A
Cited
US4556180A
Cited
US4818254A
Cited
US4840646A
Cited
US4806132A
Cited
US5030058A
Cited
US4874401A
Cited
US4838904A
Cited
US4851014A
Cited
US4857082A
Cited
US4931070A
Cited
US4944776A
Cited
US5118327A
Cited
US5030251A
Cited
US5125937A
Cited
US5102432A
Cited
US5131929A
Cited
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