Boil-off gas processing system using electric heater

• US 20030031970A1
• Filed: 08/07/2002
• Published: 02/13/2003
• Est. Priority Date: 08/09/2001
• Status: Active Grant

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Nuiya, Yoshio, Shimada, Toshiaki, Kuriiwa, Takahiro
• Granted Patent: US 7,008,219 B2
• Time in Patent Office: Days
• US Class Current: 431/204
• CPC Class Codes: F23C 13/00 Apparatus in which combustion takes place in the presence of catalytic material in a fluidised bed of catalytic particles F23C10/01; radiant gas burners using catalysis for flameless combustion F23D14/18
• CPC Class Codes: F23C 13/02 characterised by arrangements for starting the operation, e.g. for heating the catalytic material to operating temperature
• CPC Class Codes: F23C 2900/9901 Combustion process using hydrogen, hydrogen peroxide water or brown gas as fuel
• CPC Class Codes: F23G 7/07 in which combustion takes place in the presence of catalytic material
• CPC Class Codes: F23N 2237/12 catalytic burners
• CPC Class Codes: H01M 8/04201 Reactant storage and supply, e.g. means for feeding, pipes
• CPC Class Codes: H01M 8/0606 with means for production of gaseous reactants
• CPC Class Codes: H01M 8/0662 Treatment of gaseous reactants or gaseous residues, e.g. cleaning
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A boil-off gas processing system for reliably burning a boil-off gas. The system processes a boil-off gas produced from a liquid hydrogen tank which is built in a hydrogen fueled vehicle. The system includes a mixing device for introducing air into a discharge passage through which the boil-off gas from the liquid hydrogen tank passes and for mixing the air and the boil-off gas and outputting a mixed gas; a catalytic combustor for burning the mixed gas which was mixed by the mixing device, the catalytic combustor having an inlet through which the mixed gas is introduced and an outlet for discharging combustion gas; an electric heater provided at the inlet side of the catalytic combustor; and a control section for controlling energizing of the electric heater.

Claims

1. A boil-off gas processing system for processing a boil-off gas produced from a liquid hydrogen tank which is built in a hydrogen fueled vehicle, the system comprising:

a mixing device for introducing air into a discharge passage through which the boil-off gas from the liquid hydrogen tank passes and for mixing the air and the boil-off gas and outputting a mixed gas;

a catalytic combustor for burning the mixed gas which was mixed by the mixing device, the catalytic combustor having an inlet through which the mixed gas is introduced and an outlet for discharging combustion gas;

an electric heater provided at the inlet side of the catalytic combustor; and

a control section for controlling energizing of the electric heater.

2. A boil-off gas processing system as claimed in claim 1, further comprising:

a discharge valve which is attached to the discharge passage and is opened when the pressure in the liquid hydrogen tank reaches a predetermined pressure, wherein when the discharge valve is open, the boil-off gas is introduced into the mixing device,

wherein the control section controls energizing of the electric heater according to an open or closed state of the discharge valve.

3. A boil-off gas processing system as claimed in claim 1, further comprising:

a temperature measuring section for measuring a temperature of the catalytic combustor,

wherein the control section controls energizing of the electric heater based on the measured temperature of the catalytic combustor.

4. A boil-off gas processing system as claimed in claim 2, further comprising:

a temperature measuring section for measuring a temperature of the catalytic combustor,

wherein the control section controls energizing of the electric heater based on the measured temperature of the catalytic combustor.

5. A boil-off gas processing system as claimed in claim 1, wherein:

the control section starts energizing of the electric heater before the boil-off gas included in the mixed gas is introduced into the catalytic combustor.

6. A boil-off gas processing system as claimed in claim 5, further comprising:

a discharge valve which is attached to the discharge passage and is opened when the pressure in the liquid hydrogen tank reaches a first predetermined pressure, wherein when the discharge valve is open, the boil-off gas is introduced into the mixing device,

wherein the control section starts energizing of the electric heater when the pressure in the liquid hydrogen tank reaches a second predetermined pressure which is lower than the first predetermined pressure.

7. A boil-off gas processing system as claimed in claim 1, wherein the electric heater has an electric heating wire consisting of a heating wire and a catalyst which is adhered to a surface of the heating wire.

8. A boil-off gas processing system as claimed in claim 1, wherein:

the discharge passage is heated by waste heat of a combustion gas which is discharged from the catalytic combustor.

9. A boil-off gas processing system as claimed in claim 8, wherein:

a combustion gas passage for discharging the combustion gas is provided in a manner such that a portion of the discharge passage, disposed from the catalytic combustor to the upstream side of the electric heater, is surrounded by the combustion gas passage.