Gradual oxidation with heat control

• US 9,347,664 B2
• Filed: 03/09/2012
• Issued: 05/24/2016
• Est. Priority Date: 03/09/2012
• Status: Active Grant

• Current Assignee: ReductoNox Corp.
• Original Assignee: Ener-Core Power, Inc. (Ener-Core, Inc.)
• Inventors: Lampe, Steve, Hamrin, Douglas
• Primary Examiner(s): Sutherland, Steven
• Application Number:
  US13/417,050
• Publication Number:
  US 20130232943A1
• Time in Patent Office: 1,537 Days
• Field of Search: 607/74, 607/22, 607/23, 607/33, 607/77, 60/395, 60/392.81, 607/91, 60/391.82, 60/395.2, 431/268, 431/2, 431/5, 431/7, 422/168, 422/176, 422/173
• 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: F23C 2202/10 Premixing fluegas with fuel and combustion air
• CPC Class Codes: F23C 2900/99001 Cold flame combustion or flameless oxidation processes
• CPC Class Codes: F23C 9/08 for reducing temperature in combustion chamber, e.g. for protecting walls of combustion chamber
• CPC Class Codes: F23C 99/00 Subject-matter not provided for in other groups of this subclass
• 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: F23G 2206/203 with a power/heat generating installation
• CPC Class Codes: F23G 5/46 Recuperation of heat
• CPC Class Codes: F23G 7/065 using gaseous or liquid fuel
• CPC Class Codes: F23K 2900/05004 Mixing two or more fluid fuels
• CPC Class Codes: F23L 2900/07002 Injecting inert gas, other than steam or evaporated water, into the combustion chambers
• CPC Class Codes: F23M 2900/05004 Special materials for walls or lining
• CPC Class Codes: F23N 1/022 using electronic means
• CPC Class Codes: F23N 1/082 using electronic means
• CPC Class Codes: F23N 2225/16 burner temperature
• CPC Class Codes: F23N 5/003 using detectors sensitive to combustion gas properties F23N5/02, F23N5/18 - F23N5/26 take precedence
• CPC Class Codes: F23N 5/02 using devices responsive to thermal changes or to thermal expansion of a medium
• CPC Class Codes: F23R 2900/00002 Gas turbine combustors adapted for fuels having low heating value [LHV]
• CPC Class Codes: Y02E 20/12 Heat utilisation in combustion or incineration of waste
• 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
• CPC Class Codes: Y02T 50/60 : Efficient propulsion technologies, e.g. for aircraft

Abstract

Described herein are embodiments of systems and methods for oxidizing gases. In some embodiments, a reaction chamber is configured to receive a fuel gas and maintain the gas at a temperature within the reaction chamber that is above an autoignition temperature of the gas. The reaction chamber may also be configured to maintain a reaction temperature within the reaction chamber below a flameout temperature. In some embodiments, heat and product gases from the oxidation process can be used, for example, to drive a turbine, reciprocating engine, and injected back into the reaction chamber.

Claims

1. A system for oxidizing fuel, comprising:

an oxidizer having a reaction chamber with an inlet and an outlet, the reaction chamber configured to receive a gas comprising an oxidizable fuel through the inlet and to maintain an oxidation process within the reaction chamber;

a sensor that detects when a reaction chamber inlet temperature of the gas at an inlet side within the reaction chamber drops below an autoignition threshold of the-fuel; and

a controller that outputs instructions, based on the reaction chamber inlet temperature, to a control module (i) to increase flow of media from an outlet side within the reaction chamber to the inlet side within the reaction chamber, (ii) to contact the media with the gas, and (iii) to change the reaction chamber inlet temperature of the gas to above the autoignition threshold, such that the gas within the reaction chamber oxidizes without a catalyst.

2. The system of claim 1, wherein the media is a flue gas from the reaction chamber.

3. The system of claim 2, wherein the flue gas comprises a diluent.

4. The system of claim 1, wherein the reaction chamber is configured to maintain oxidation of the gas beneath a flameout temperature of the fuel within the reaction chamber.

5. The system of claim 1, further comprising a turbine or a piston engine that receives gas from the reaction chamber and expands the gas.

6. The system of claim 1, further comprising a compressor that receives and compresses gas, comprising a fuel mixture, prior to introduction of the fuel mixture into the reaction chamber.

7. The system of claim 1, wherein the oxidizable fuel comprises at least one of hydrogen, methane, ethane, ethylene, natural gas, propane, propylene, propadiene, n-butane, iso-butane, butylene-1, butadiene, iso-pentane, n-pentane, acetylene, hexane, and carbon monoxide.

8. A system for oxidizing fuel, comprising:

an oxidizer having a reaction chamber with an inlet and an outlet, the reaction chamber configured to receive a gas comprising an oxidizable fuel through the inlet and to maintain an oxidation process within the reaction chamber;

a sensor that detects when a reaction chamber inlet temperature of the gas at an inlet side within the reaction chamber drops below an autoignition threshold of the fuel; and

a control module that, based on the reaction chamber inlet temperature, (i) increases flow of media from an outlet side within the reaction chamber to the inlet side within the reaction chamber, (ii) contacts the media with the gas, and (iii) maintains the reaction chamber inlet temperature above the autoignition threshold.

9. The system of claim 8, wherein the media is a flue gas from the reaction chamber.

10. The system of claim 9, wherein the flue gas comprises a diluent.

11. The system of claim 8, wherein the control module is configured to maintain an actual temperature within the reaction chamber beneath a flameout temperature of the fuel.

12. The system of claim 8, further comprising a turbine or a piston engine that receives gas from the reaction chamber and expands the gas.

13. The system of claim 8, further comprising a compressor that receives and compresses gas, comprising a fuel mixture, prior to introduction of the gas into the reaction chamber.

14. The system of claim 8, wherein the oxidizable fuel comprises at least one of hydrogen, methane, ethane, ethylene, natural gas, propane, propylene, propadiene, n-butane, iso-butane, butylene-1, butadiene, iso-pentane, n-pentane, acetylene, hexane, and carbon monoxide.

15. A system for oxidizing fuel, comprising:

an oxidizer having a reaction chamber with an inlet and an outlet, the reaction chamber configured to receive a gas comprising an oxidizable fuel through the inlet and to maintain an oxidation process;

a recirculation pathway connected to an outlet side of the reaction chamber and an inlet side of the reaction chamber; and

a control module that, when a reaction chamber inlet temperature of the gas at the inlet side drops below an autoignition threshold of the fuel, (i) increases flow of media along the recirculation pathway from the outlet side to the inlet side, (ii) contacts the media with the gas, and (iii) maintains the reaction chamber inlet temperature above the autoignition threshold of the fuel, such that the fuel oxidizes within the reaction chamber above the autoignition threshold and beneath a flameout temperature of the fuel.

16. The system of claim 15, further comprising a sensor that detects when the reaction chamber inlet temperature approaches the autoignition threshold.

17. The system of claim 15, wherein the media is flue gas from the reaction chamber.

18. The system of claim 15, further comprising a turbine or a piston engine that receives gas from the reaction chamber and expands the gas.

19. The system of claim 15, further comprising a compressor that receives and compresses gas, comprising a fuel mixture, prior to introduction of the fuel mixture into the reaction chamber.

20. The system of claim 15, wherein the oxidizable fuel comprises at least one of hydrogen, methane, ethane, ethylene, natural gas, propane, propylene, propadiene, n-butane, iso-butane, butylene-1, butadiene, iso-pentane, n-pentane, acetylene, hexane, and carbon monoxide.