Supplying gaseous fuel from a liquid state to an internal combustion engine

• US 9,863,365 B2
• Filed: 12/04/2014
• Issued: 01/09/2018
• Est. Priority Date: 06/05/2012
• Status: Active Grant

• Current Assignee: Westport Fuel Systems Canada Inc. (Westport Fuel Systems, Inc.)
• Original Assignee: Westport Power Inc. (Westport Fuel Systems, Inc.)
• Inventors: Melanson, Bradley E., Mumford, David K., Blomerus, Paul M., McKinnon, Melissa S. A.
• Primary Examiner(s): Lathers, Kevin A
• Application Number:
  US14/561,184
• Publication Number:
  US 20150083055A1
• Time in Patent Office: 1,132 Days
• CPC Class Codes: F02B 63/04 for electric generators
• CPC Class Codes: F02G 5/04 in combination with other waste heat from combustion engines
• CPC Class Codes: F02M 21/02 for gaseous fuels
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels

Abstract

An improved apparatus supplies gaseous fuel from a liquid state to an internal combustion engine comprising an electrical energy generating apparatus for generating electrical energy from a store of chemical energy. A liquid pumping apparatus for pumping the gaseous fuel in the liquid state includes an energy converter for converting the electrical energy to mechanical energy which drives the liquid pumping apparatus. The liquid pumping apparatus also includes a first heat exchanger for vaporizing the gaseous fuel received from the pumping apparatus and a controller programmed to operate the liquid pumping apparatus to maintain a pressure of the gaseous fuel supplied to the internal combustion engine within a predetermined range.

Claims

1. A method for supplying gaseous fuel from a liquid state to a first internal combustion engine comprising:

consuming a combustible fuel in a second internal combustion engine;

driving an electrical generator with said second internal combustion engine, whereby said electrical generator generates electrical energy;

pumping said gaseous fuel in said liquid state by transforming at least some of said electrical energy into mechanical work;

vaporizing said gaseous fuel pumped from said liquid state with waste heat generated by operating said second internal combustion engine; and

delivering said gaseous fuel vaporized from said liquid state to said first internal combustion engine, wherein a pressure of said gaseous fuel delivered to said first internal combustion engine is maintained within a predetermined range by said pumping.

2. The method of claim 1, further comprising vaporizing said gaseous fuel pumped from said liquid state with heat generated by transforming at least some of said electrical energy into thermal energy.

3. The method of claim 1, further comprising vaporizing said gaseous fuel pumped from said liquid state with heat generated by burning boil-off gas from said gaseous fuel in said liquid state.

4. The method of claim 1, further comprising:

generating heat by transforming at least some of said electrical energy into thermal energy at least before said first internal combustion engine starts;

vaporizing said gaseous fuel pumped from said liquid state with said heat;

generating waste heat by operating said first internal combustion engine; and

vaporizing said gaseous fuel pumped from said liquid state with said waste heat.

5. The method of claim 1, further comprising:

generating heat by burning boil-off gas from said gaseous fuel in said liquid state at least before said first internal combustion engine starts;

vaporizing said gaseous fuel pumped from said liquid state with said heat;

generating waste heat by operating said first internal combustion engine; and

vaporizing said gaseous fuel pumped from said liquid state with said waste heat from said first internal combustion engine.

6. An apparatus for supplying gaseous fuel from a liquid state to a first internal combustion engine comprising:

a second internal combustion engine for consuming a combustible fuel;

an electrical generator driven by said second internal combustion engine for generating electrical energy;

a pump for pumping said gaseous fuel in said liquid state comprising an energy converter for converting at least some of said electrical energy to mechanical energy which drives said pump;

a first heat exchanger for vaporizing said gaseous fuel received from said pump;

piping conduit for communicating waste heat in a first heat exchange fluid from said second internal combustion engine to said first heat exchanger, said waste heat in said first heat exchange fluid for vaporizing said gaseous fuel in said liquid state; and

a controller programmed to operate said pump to maintain a pressure of said gaseous fuel supplied to said first internal combustion engine within a predetermined range.

7. The apparatus of claim 6, further comprising a second heat exchanger for heating a second heat exchange fluid by transforming at least some of said electrical energy into heat, wherein said second heat exchange fluid transfers heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state.

8. The apparatus of claim 6, further comprising a second heat exchanger for heating a second heat exchange fluid by generating heat by burning boil-off gas from said gaseous fuel in said liquid state, wherein said second heat exchange fluid transfers heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state.

9. The apparatus of claim 6, further comprising a second heat exchanger for heating a second heat exchange fluid by transferring waste heat from said first internal combustion engine to said second heat exchange fluid, wherein said second heat exchange fluid transfers heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state.

10. The apparatus of claim 6, further comprising a second heat exchanger for heating a second heat exchange fluid by transferring waste heat from said first internal combustion engine to said second heat exchange fluid;

and

at least one more heat exchanger operable for one of;

(i) heating said second heat exchange fluid by transforming at least some of said electrical energy into heat; and

(ii) heating said second heat exchange fluid with heat generated by burning boil-off gas from said gaseous fuel in said liquid state, wherein said second heat exchange fluid transfers heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state.

11. The apparatus of claim 6, further comprising a heat exchange loop comprising engine coolant from said first internal combustion engine as a second heat exchange fluid for transferring heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state.

12. The apparatus of claim 11, further comprising at least one more heat exchanger operable for one of:

(i) heating said second heat exchange fluid by transforming at least some of said electrical energy into heat; and

(ii) heating said second heat exchange fluid with heat generated by burning boil-off gas from said gaseous fuel in said liquid state.

13. The apparatus of claim 6, further comprising:

a first heat exchange loop comprising engine coolant from said first internal combustion engine as a second heat exchange fluid for transferring heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state; and

a second heat exchange loop comprising a third heat exchange fluid for transferring heat to said gaseous fuel in said first heat exchanger for vaporizing said gaseous fuel in said liquid state;

at least one more heat exchanger operable for one of;

(i) heating said third heat exchange fluid by transforming at least some of said electrical energy into heat; and

(ii) heating said third heat exchange fluid with heat generated by burning boil-off gas from said gaseous fuel in said liquid state.

14. The apparatus of claim 6, further comprising a second heat exchanger for heating said first heat exchange fluid by transforming said at least some of electrical energy into heat thereby increasing a temperature of said first heat exchange fluid.

15. The apparatus of claim 6, further comprising a second heat exchanger for heating said first heat exchange fluid by burning boil-off gas from said gaseous fuel in said liquid state thereby increasing a temperature of said first heat exchange fluid.