Self-regulating hydrogen generator

• US 6,274,093 B1
• Filed: 08/06/1998
• Issued: 08/14/2001
• Est. Priority Date: 08/06/1998
• Status: Expired due to Fees

• Current Assignee: Ball Aerospace & Technologies Corporation (Ball Corporation)
• Original Assignee: Ball Aerospace & Technologies Corporation (Ball Corporation)
• Inventors: Lynch, Frank, Long, Eugene, Schmidt, Jeffrey A.
• Primary Examiner(s): TRAN, HIEN THI
• Application Number:
  US09/130,395
• Time in Patent Office: 1,104 Days
• Field of Search: 48/61, 252/188.25, 252/188.26, 422/113, 422/129, 423/648.1
• US Class Current: 422/129
• CPC Class Codes: B01J 2219/00164 controlling the flow
• CPC Class Codes: B01J 7/00 Apparatus for generating gases production of inert gas mixtures B01J19/14; for generating specific gases, see the relevant subclasses, e.g. C01B, C10J ; in "air bags" on vehicles B60R21/26; for starter gas F02C7/26; blasting cartridges for producing gas under pressure F42B3/04
• CPC Class Codes: C01B 3/065 from a hydride
• CPC Class Codes: H01M 8/0606 with means for production of gaseous reactants
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: H01M 8/0662 Treatment of gaseous reactants or gaseous residues, e.g. cleaning
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A hydrogen generating apparatus that includes a reactant with a vapor phase at greater than atmospheric pressure. The apparatus includes a tank for housing the reactant, such as ammonia. Ammonia communicates with a reactor having a solid reactant, such as lithium aluminum tetrahydride. A check valve is located between the tank and the reactor and is used to control the flow of ammonia to the reactor. Heat generated by the reaction is useful in raising the temperature of the reactant in the tank. The reactor can also include a gas flow enhancing material that facilitates gas flow through the reactor. A filter and getters are employed downstream of the reactor to remove unwanted solids and impurities from the hydrogen gas stream.

Claims

1. An apparatus for generating hydrogen, comprising:

ammonia in which a majority thereof, by at least one of weight and volume is different from water;

a solid reactant;

a tank that contains said ammonia, with said ammonia being associated with a first pressure in said tank;

a reactor that contains said solid reactant used in generating hydrogen gas; and

a control device disposed between said tank and said reactor that controls movement of said ammonia from said tank to said reactor, wherein said control device allows said ammonia to pass therethrough depending on said first pressure of said ammonia in said tank and also depending on a second pressure in said reactor and wherein substantially only said control device controls passage of said ammonia between said tank and said reactor such that said control device is free of connection to any controller and pressure sensor used to control said control device.

2. An apparatus, as claimed in claim 1, wherein:

said ammonia has a latent heat of vaporization parameter lower than water.

3. An apparatus, as claimed in claim 1, wherein:

said ammonia includes at least one of the following;

anhydrous ammonia, hydrous ammonia and hydrogen rich compositions that have positive vapor pressures when subject to a temperature equal to and less than ambient temperature.

4. An apparatus, as claimed in claim 1, wherein:

said control device includes a valve member that allows movement of said ammonia from said tank to said reactor.

5. An apparatus, as claimed in claim 1, wherein:

said ammonia in said tank that passes from said tank to said reactor through said control device is ammonia vapor.

6. An apparatus, as claimed in claim 1, wherein:

said tank is located adjacent to said reactor wherein said tank increases in temperature due to heat from said reactor.

7. An apparatus, as claimed in claim 1, further including:

means for substantially preventing unwanted substances from being part of hydrogen gas that is output from the apparatus.

8. An apparatus, as claimed in claim 7, wherein:

said ammonia includes ammonia vapor and said means for substantially preventing includes first means for substantially preventing solid particles from passing therethrough and second means for substantially preventing at least said ammonia vapor from passing therethrough.

9. An apparatus, as claimed in claim 7, wherein:

said ammonia includes ammonia vapor and said means for substantially preventing includes means located downstream of said solid reactant for substantially removing said ammonia vapor from hydrogen gas.

10. An apparatus, as claimed in claim 7, wherein:

said reactor contains unwanted organic fluids and said means for substantially preventing includes means located downstream of said solid reactant for substantially removing said unwanted organic fluids.

11. An apparatus, as claimed in claim 10, wherein:

said means for substantially removing said unwanted organic fluids includes an activated carbon material.

12. An apparatus, as claimed in claim 9, wherein:

said means for substantially removing said ammonia vapor includes at least one of sulfuric acid, sodium hydrogen sulfate and its monohydrate.

13. An apparatus, as claimed in claim 1, wherein:

said reactor further includes a gas flow enhancing material different from said solid reactant for increasing yield of hydrogen gas, and in which said gas flow enhancing material constitutes at least five percent by volume of the combination of said solid reactant and said gas flow enhancing material.

14. An apparatus, as claimed in claim 1, wherein:

said solid reactant includes a hydride.

15. An apparatus, as claimed in claim 1, wherein:

said solid reactant substantially continuously is at ambient temperature during the time said ammonia is not present in said reactor.

16. An apparatus, as claimed in claim 1, wherein:

said ammonia includes an ammonia vapor and substantially all of said ammonia passing from said tank to said reactor is said ammonia vapor.

17. An apparatus, as claimed in claim 4, wherein:

said valve member includes a check valve.

18. An apparatus, as claimed in claim 14, wherein:

said hydride includes lithium aluminum tetrahydride.

19. An apparatus for generating hydrogen, comprising:

ammonia in which a majority thereof, by at least one of weight and volume, is different from water;

a solid reactant;

a tank that houses said ammonia that includes at least a liquid phase and a vapor phase, wherein a first pressure is developed in said tank using said ammonia;

a reactor that houses at least said solid reactant for use in generating hydrogen gas, wherein a second pressure is developed in said reactor using hydrogen gas; and

a flow control member disposed between said tank and said reactor for controlling flow of said ammonia from said tank to said reactor using a difference between said first pressure and said second pressure;

wherein said flow control member allows said ammonia to pass from said tank to said reactor independently of any external controller and any pressure sensor and in which said solid reactant is substantially continuously at ambient temperature in said reactor during the time said ammonia is not present in said reactor.

20. An apparatus, as claimed in claim 19, wherein:

said ammonia includes one of the following;

anhydrous ammonia, hydrous ammonia and hydrogen rich compositions that have a positive vapor pressure when at a temperature equal to or less than ambient temperature.

21. An apparatus, as claimed in claim 19, wherein:

said reactor also contains a gas flow enhancing material that by volume is at least 5 percent of the total volume of the combination of said solid reactant and said gas flow enhancing material.

22. An apparatus, as claimed in claim 19, further comprising:

means for substantially preventing at least said ammonia from being part of hydrogen gas that is generated and with said means for substantially preventing being positioned downstream of said solid reactant.