System and method for treating hydrogen to be stored in a salt cavern and supplying therefrom

• US 9,718,618 B2
• Filed: 09/02/2014
• Issued: 08/01/2017
• Est. Priority Date: 09/02/2014
• Status: Active Grant

• Current Assignee: Praxair Technology Incorporated (Linde Plc)
• Original Assignee: Praxair Technology Incorporated (Linde Plc)
• Inventors: Oates, Rommel M.
• Primary Examiner(s): Kreck, John
• Assistant Examiner(s): OQUENDO, CARIB A
• Application Number:
  US14/475,120
• Publication Number:
  US 20160060038A1
• Time in Patent Office: 1,064 Days
• CPC Class Codes: B01D 53/265 by refrigeration (condensation)
• CPC Class Codes: B65G 5/00 Storing fluids in natural or artificial cavities or chambers in the earth
• CPC Class Codes: C01B 2203/043 Regenerative adsorption process in two or more beds, one for adsorption, the other for regeneration
• CPC Class Codes: C01B 2203/0465 Composition of the impurity
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 2203/0495 the impurity being water
• CPC Class Codes: C01B 3/00 Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it separation of gases by physical means B01D; Purification of hydrogen production of water gas or synthesis gas from solid carbonaceous material C10J; purifying or modifying the chemical compositions of combustible technical gases containing carbon monoxide C10K
• CPC Class Codes: C01B 3/506 at low temperatures
• CPC Class Codes: F17C 3/005 Underground or underwater containers or vessels storing in natural or artificial cavities in the earth in general B65G5/00
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• CPC Class Codes: Y02P 30/00 Technologies relating to oil refining and petrochemical industry

Abstract

A novel system and method for storing hydrogen in a salt cavern and supplying therefrom is provided. Hydrogen product withdrawn from a hydrogen pipeline may be chilled prior to being introduced into a cavern in order to cool at least a portion of the walls of the salt cavern so that one or more layers of the localized portion of the walls attains a stabilized state whereby contaminant release from the walls is suppressed. The present invention anticipates and strategically plans for contaminant intrusion form a salt cavern in order to reduce the degree of contaminant intrusion from a salt cavern while also allowing the stored hydrogen to have more absorption capacity for water vapor by virtue of entering the salt cavern in a sufficiently drier state. Alternatively, or in addition thereto, a crude hydrogen stream may be withdrawn from the cavern and chilled prior to introducing to the hydrogen pipeline.

Claims

1. A method for treating a moisture-containing hydrogen product to be stored in a salt cavern, comprising:

removing hydrogen product from a hydrogen pipeline;

compressing the hydrogen product to produce a compressed hydrogen product;

cooling the compressed hydrogen product to condense at least a portion of water vapor prior to the compressed hydrogen product entering the salt cavern;

removing the water vapor condensate to produce a compressed and chilled hydrogen product; and

introducing the compressed and chilled hydrogen product into the salt cavern to produce chilled and stored hydrogen within the salt cavern.

2. The method of claim 1, further comprising the steps of:

reducing a temperature of at least a localized portion of walls of the salt cavern by contacting at least a portion of the chilled and stored hydrogen with the localized portion of the walls so that one or more layers of the localized portion of the walls attains a stabilized state whereby contaminant release from said walls is suppressed.

3. The method of claim 1, wherein the chilled and stored hydrogen is—

dry to have capacity to absorb water vapor contained in the cavern to a level at or below a product purity specification.

4. The method of claim 3, further comprising:

withdrawing said chilled and stored hydrogen from the salt cavern to produce a supply of hydrogen; and

introducing the supply of hydrogen into the pipeline.

5. The method of claim 4, wherein the introducing of the supply of hydrogen into the pipeline is characterized by an absence of drying of the supply of hydrogen.

6. The method of claim 5, further comprising sampling concentration levels of one or more contaminants in the supply of hydrogen, said contaminants selected group from the group consisting of hydrocarbons, water vapor, sulfur compounds and carbon dioxide.

7. The method of claim 3, further comprising:

withdrawing said stored hydrogen from the salt cavern to produce a supply of hydrogen product;

chilling the supply of hydrogen to remove a sufficient amount of water vapor having an impurity level of water vapor at or below a product purity specification; and

introducing the hydrogen product into the hydrogen pipeline.

8. The method of claim 1, wherein the compressed and chilled hydrogen to be introduced into the salt cavern is characterized by an impurity level of water vapor at or below a product purity specification.

9. The method of claim 1, further comprising:

contacting at least a portion of the chilled and stored hydrogen with walls of the salt cavern; and

reducing a temperature of the walls to a temperature sufficient to lower the rate of infiltration of a substantial portion of contaminants contained therein, wherein said contaminants is selected from the group consisting of water vapor, carbon dioxide, hydrocarbons, sulfur-containing compounds and any combination thereof.

10. A system for storing hydrogen product in a salt cavern, comprising:

a compressor configured to pressurize hydrogen product within the salt cavern to form stored hydrogen;

an aftercooler situated downstream of the compressor, said aftercooler configured to remove a heat of compression from the pressurized hydrogen product;

a chiller configured to impart additional cooling beyond the heat of compression to condense at least water vapor from the hydrogen product, said chiller in fluid communication with the compressor;

a liquid-vapor separator vessel configured collect and accumulate at least the removed water vapor condensate, said collection vessel located downstream and in fluid communication with the chiller;

a flow network positioned between the salt cavern and the compressor, the chiller and the collection vessel, said flow network comprising a first leg and a second leg;

the first leg in flow communication with the salt cavern to introduce product hydrogen into the salt cavern to form stored hydrogen that is chilled to a temperature sufficient to remove a portion of water vapor to produce a chilled and stored hydrogen product; and

the second leg in flow communication with a hydrogen pipeline and the first leg to withdraw the stored and chilled hydrogen from the salt cavern.

11. The system of claim 10, further comprising:

a third leg in flow communication with the salt cavern and the chiller to re-chill and/or separate condensate from the stored and chilled hydrogen to produce a supply of hydrogen; and

a fourth leg in flow communication with the first leg and the second leg to return the supply of hydrogen to the hydrogen pipeline.

12. The system of claim 10, further comprising a temperature detection means for monitoring a temperature of the cavern.

13. The system of claim 10, further comprising an analyzer bank for measuring at least water vapor, said analyzer positioned along the second leg.

14. The system of claim 10, wherein said system is characterized by the absence of purification equipment.

15. A method for supplying hydrogen to a hydrogen pipeline from an underground hydrogen storage cavern, comprising:

removing hydrogen product from a hydrogen pipeline;

compressing the hydrogen product to produce a compressed hydrogen product;

cooling the compressed hydrogen product to remove heat of compression from the compressed hydrogen product;

imparting additional cooling of the compressed hydrogen product to condense at least a portion of water vapor to create water vapor condensate prior to the compressed hydrogen product entering the salt cavern;

removing the water vapor condensate to produce a compressed and chilled hydrogen product;

followed by

introducing the compressed and chilled hydrogen product into the salt cavern to produce chilled and stored hydrogen within the salt cavern;

withdrawing a crude hydrogen stream from a salt cavern, the crude hydrogen stream comprising one or more contaminants imparted by the salt cavern;

separating at least a portion of the one or more contaminants to form a condensate from the crude hydrogen stream to produce a hydrogen product; and

introducing the hydrogen product into the hydrogen pipeline to supply additional hydrogen to the pipeline.

16. The method of claim 15, further comprising cooling the crude hydrogen stream to a temperature less than about 200 deg F. but above the liquefaction temperature of the crude hydrogen stream.

17. The method of claim 15, wherein said crude hydrogen stream is derived from a compressed hydrogen product stream that is cooled prior to introduction in the underground hydrogen storage cavern.

18. The method of claim 15, wherein said contaminants is selected from the group consisting of water vapor, carbon dioxide, hydrocarbons, sulfur compounds and any combination thereof.

19. The method of claim 15, further comprising introducing the hydrogen product into the hydrogen pipeline, wherein said hydrogen product comprises contaminants each of which has an impurity level at or below a product purity specification.

20. A method for operating an underground salt cavern, comprising the steps of:

detecting one or more contaminants in a crude hydrogen stream withdrawn from the cavern to exceed a product purity specification; and

in response thereto

increasing cooling of a compressed hydrogen stream that is removed as hydrogen product from a hydrogen pipeline; and

increasing cooling of the crude hydrogen stream that is withdrawn from the cavern;

wherein the cooling of the compressed hydrogen stream and the cooling of the crude hydrogen stream enables a lowering and maintaining of the one or more contaminant at or below a product purity specification.

21. A method for treating a hydrogen product to be stored in a salt cavern, comprising:

removing hydrogen product from a hydrogen pipeline;

compressing the hydrogen product to produce a compressed hydrogen product;

removing at least a first portion of water vapor from the compressed hydrogen product; and

introducing the compressed hydrogen product into the salt cavern to produce stored hydrogen.

22. The method of claim 21, further comprising:

withdrawing at least a portion of the stored hydrogen from the salt cavern as a crude hydrogen stream;

removing at least a second portion of water vapor from the crude hydrogen stream to produce a gaseous hydrogen product; and

supplying the gaseous hydrogen product to the hydrogen pipeline.

23. The method of claim 21, further comprising:

withdrawing at least a portion of the stored hydrogen from the salt cavern as a crude hydrogen stream;

removing one or more contaminants within the crude hydrogen stream to produce a gaseous hydrogen product; and

supplying the gaseous hydrogen product to the hydrogen pipeline.