Fuel oxidation in a gas turbine system

• US 9,587,564 B2
• Filed: 03/17/2014
• Issued: 03/07/2017
• Est. Priority Date: 10/23/2007
• Status: Active Grant

• Current Assignee: ReductoNox Corp.
• Original Assignee: Ener-Core Power, Inc. (Ener-Core, Inc.)
• Inventors: Prabhu, Edan
• Primary Examiner(s): SUTHERLAND, STEVEN M
• Application Number:
  US14/217,106
• Publication Number:
  US 20140196467A1
• Time in Patent Office: 1,086 Days
• Field of Search: 607/75, 607/76, 607/77, 60/392.81, 60/393, 608/00, 60/394.63, 607/33, 60/395.3
• US Class Current: 1/1
• CPC Class Codes: F02C 3/205 in a fluidised-bed combustor in combination with a steam cycle see F01K23/061; fluidised-bed apparatus in general B01J8/18; fluidised-bed combustors in general F23C10/00
• CPC Class Codes: F02C 3/22 the fuel or oxidant being gaseous at standard temperature and pressure F02C3/28 takes precedence
• CPC Class Codes: F02C 9/28 Regulating systems responsive to plant or ambient parameters, e.g. temperature, pressure, rotor speed F02C9/30 - F02C9/38, F02C9/44 take precedence
• CPC Class Codes: F23C 2900/99001 Cold flame combustion or flameless oxidation processes
• CPC Class Codes: F23C 99/006 Flameless combustion stabilised within a bed of porous heat-resistant material F23C13/00 takes precedence; gas burners with radiant combustion on a porous surface F23D14/16
• CPC Class Codes: F23R 3/26 Controlling the air flow
• CPC Class Codes: F23R 3/28 characterised by the fuel supply burners F23D
• CPC Class Codes: Y02E 20/34 Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Abstract

A mixture of air and fuel is received into a reaction chamber of a gas turbine system. The fuel is oxidized in the reaction chamber, and a maximum temperature of the mixture in the reaction chamber is controlled to be substantially at or below an inlet temperature of a turbine of the gas turbine system. The oxidation of the fuel is initiated by raising the temperature of the mixture to or above an auto-ignition temperature of the fuel. In some cases, the reaction chamber may be provided without a fuel oxidation catalyst material.

Claims

1. A method of operating a gas turbine system, comprising:

oxidizing a fuel of an air and fuel mixture in a reaction chamber, wherein a fuel oxidation catalyst material is not used during the oxidizing; and

controlling a maximum temperature of the air and fuel mixture to be between an auto-ignition temperature of the fuel and 1300°

C. by receiving a control flow comprising supplemental fuel through a plurality of ports located at a plurality of locations along a reaction chamber flow path in the reaction chamber, each of the plurality of ports being connected to a supplemental fuel source for introduction of the supplemental fuel into the reaction chamber through the plurality of ports.

2. The method of claim 1, wherein the air and fuel mixture is a mixture of air and one or more of oxidizable gas, oxidizable vapor, or oxidizable particles.

3. The method of claim 1, wherein the reaction chamber defines an air and fuel mixture flow path of sufficient duration that a flow rate of the air and fuel mixture along the air and fuel mixture flow path provides sufficient time for the fuel to oxidize to completion.

4. The method of claim 1, further comprising heating the air and fuel mixture before oxidizing the fuel in the reaction chamber.

5. The method of claim 1, wherein the control flow further comprises air, and controlling the maximum temperature of the air and fuel mixture comprises increasing an amount of the control flow received into the reaction chamber to decrease the maximum temperature of the air and fuel mixture.

6. The method of claim 1, wherein the control flow further comprises a non-reactive fluid, and controlling the maximum temperature of the air and fuel mixture comprises increasing an amount of the control flow received into the reaction chamber to decrease the maximum temperature of the air and fuel mixture.

7. The method of claim 1, wherein oxidizing the fuel comprises gradually oxidizing a majority of the fuel.

8. The method of claim 1, further comprising

detecting a characteristic comprising a temperature at one or more positions in the reaction chamber;

and

adjusting an amount of the control flow received into the reaction chamber based at least in part on the characteristic.

9. A method of operating a gas turbine system, the method comprising:

oxidizing a fuel of an air and fuel mixture in a reaction chamber of the gas turbine system while controlling a maximum temperature of the air and fuel mixture in the reaction chamber to be between an auto-ignition temperature of the fuel and 1300°

C., wherein a fuel oxidation catalyst material is not used during the oxidation;

receiving a control flow comprising supplemental fuel (i) from a supplemental fuel source, (ii) through a plurality of ports located at a plurality of locations along a reaction chamber flow path in the reaction chamber, and (iii) into the reaction chamber, each of the plurality of ports being spaced from another of the plurality of ports along the reaction chamber flow path; and

adjusting the control flow to control the maximum temperature of the air and fuel mixture.

10. The method of claim 9, further comprising, prior to oxidizing the fuel, pressurizing the air and fuel mixture in a compressor of the gas turbine system.

11. The method of claim 9, further comprising detecting a characteristic comprising a temperature at one or more positions in the reaction chamber;

wherein adjusting the control flow comprises adjusting an amount of the control flow received into the reaction chamber based at least in part on the characteristic.

12. The method of claim 9, further comprising expanding the air and fuel mixture in a turbine of the gas turbine system.

13. The method of claim 9, wherein the air and fuel mixture comprises a fuel concentration below a sustainable-combustion threshold concentration.

14. The method of claim 9, wherein oxidizing the fuel comprises gradually oxidizing all of the fuel.

15. The method of claim 9, a plurality of temperatures along the reaction chamber flow path defines a temperature gradient, and the temperature gradient generally increases from a flow path inlet temperature to a flow path outlet temperature.

16. The method of claim 9, wherein the fuel is oxidized in the reaction chamber flow path, the method further comprising at least one of:

adjusting a flow rate of the air and fuel mixture along the reaction chamber flow path;

adjusting a fuel concentration of the air and fuel mixture;

receiving into the reaction chamber flow path air to decrease the temperature of the air and fuel mixture;

receiving into the reaction chamber flow path air to decrease a rate of increase of the temperature of the air and fuel mixture;

receiving into the reaction chamber flow path one or more non-reactive fluids to decrease a rate of increase of the temperature of the air and fuel mixture;

or

receiving into the reaction chamber flow path one or more non-reactive fluids to decrease the temperature of the air and fuel mixture.

17. The method of claim 9, further comprising heating the air and fuel mixture before oxidizing the air and fuel mixture in the reaction chamber.

18. The method of claim 9, wherein the control flow further comprises air, and controlling the maximum temperature of the air and fuel mixture comprises increasing an amount of the control flow received into the reaction chamber to decrease the maximum temperature of the air and fuel mixture.

19. The method of claim 9, wherein the control flow further comprises a non-reactive fluid, and controlling the maximum temperature of the air and fuel mixture comprises increasing an amount of the control flow received into the reaction chamber to decrease the maximum temperature of the air and fuel mixture.

20. A gas turbine system comprising:

a reaction chamber adapted to oxidize a fuel of an air and fuel mixture and maintain a maximum temperature of the air and fuel mixture in the reaction chamber between an auto-ignition temperature of the fuel and 1300°

C., wherein the reaction chamber is provided without a fuel oxidation catalyst material;

a plurality of ports located at a plurality of locations along a reaction chamber flow path in the reaction chamber, each of the plurality of ports being connected to a supplemental fuel source;

a controller adapted to adjust a control flow of a supplemental fuel through the plurality of ports into the reaction chamber to control the maximum temperature of the air and fuel mixture within the reaction chamber.

21. The gas turbine system of claim 20, further comprising a compressor having a compressor inlet and a compressor outlet, the compressor adapted to compress the air and fuel mixture between the compressor inlet and the compressor outlet, the compressor outlet being in communication with an inlet of the reaction chamber.

22. The gas turbine system of claim 20, further comprising a sensor adapted to detect a characteristic comprising a temperature at one or more positions in the reaction chamber, wherein the controller is adapted to adjust an amount of the control flow received into the reaction chamber based at least in part on the characteristic.

23. The gas turbine system of claim 20, further comprising a turbine in communication with the reaction chamber, the turbine adapted to convert energy from the air and fuel mixture into rotational movement.

24. The gas turbine system of claim 20, the reaction chamber comprising a reaction chamber inlet to receive the air and fuel mixture into the reaction chamber, and a flame arrestor to reduce transfer of heat energy from the reaction chamber inlet to upstream of the reaction chamber inlet.

25. The gas turbine system of claim 20, wherein each of the plurality of ports is further connected to a non-reactive fluid source and an air source for introduction of a non-reactive fluid and air into the reaction chamber through the plurality of ports.