Hybrid gradual oxidation

• US 9,534,780 B2
• Filed: 03/09/2012
• Issued: 01/03/2017
• Est. Priority Date: 03/09/2012
• Status: Active Grant

• Current Assignee: ReductoNox Corp.
• Original Assignee: Ener-Core Power, Inc. (Ener-Core, Inc.)
• Inventors: Martin, Richard, Armstrong, Jeffrey, Hamrin, Douglas
• Primary Examiner(s): PEREIRO, JORGE ANDRES
• Application Number:
  US13/417,165
• Publication Number:
  US 20130233213A1
• Time in Patent Office: 1,761 Days
• Field of Search: 431/5, 431/11, 431/12, 431/7, 110/348, 60/395.11, 60/395.2
• US Class Current: 1/1
• 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: F23C 99/008 Combustion methods wherein flame cooling techniques other than fuel or air staging or fume recirculation are used
• 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 5/50 Control or safety arrangements
• 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: F23L 7/00 Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
• 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 5/022 using electronic means F23N5/04 - F23N5/14 take precedence
• 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 configured to receive and oxidize a gas mixture comprising an oxidizable fuel in a gradual oxidation process within the reaction chamber;

an inlet configured to introduce water into the reaction chamber during the oxidation process, the water being at an inlet temperature lower than an internal temperature of the reaction chamber, such that the water is heated as it is introduced into the reaction chamber; and

an outlet configured to extract the heated water from the reaction chamber; and

a controller configured to;

calculate an adiabatic temperature of the gas mixture;

determine when the adiabatic temperature exceeds or is equal to a flameout temperature of the gas mixture;

when the adiabatic temperature exceeds or is equal to the flameout temperature, output a first signal to regulate an introduction of the water such that the internal temperature within the reaction chamber is reduced; and

when the adiabatic temperature is below the flameout temperature, output a second signal to regulate the introduction of the water such that the internal temperature within the reaction chamber exceeds an autoignition temperature within the reaction chamber.

2. The system of claim 1, wherein inlet is configured to introduce a liquid into the reaction chamber.

3. The system of claim 2, wherein the liquid is introduced into the reaction chamber by passing through one or more coils within the reaction chamber.

4. The system of claim 3, wherein the coils are not in fluid communication with the reaction chamber.

5. The system of claim 2, wherein the liquid is introduced into the reaction chamber by injecting the liquid into the reaction chamber, such that the liquid mixes with the gas mixture within the reaction chamber.

6. The system of claim 1, wherein the inlet is configured to introduce the water into the reaction chamber as a gas.

7. The system of claim 6, wherein the gas is introduced into the reaction chamber by passing through one or more coils within the reaction chamber.

8. The system of claim 7, wherein the coils do not permit mixing of the gas and the gas mixture within the reaction chamber.

9. The system of claim 6, wherein the gas is introduced into the reaction chamber by injecting the gas into the reaction chamber, such that the gas mixes with the gas mixture within the reaction chamber.

10. The system of claim 1, wherein the outlet is configured to extract the heated water from the reaction chamber as a gas.

11. The system of claim 10, wherein the outlet is configured to redirect the gas into the reaction chamber, such that the gas mixes with the gas mixture within the reaction chamber.

12. The system of claim 1, wherein when an adiabatic reaction temperature within the reaction chamber is lower than and approaches the flameout temperature, the water is introduced into the reaction chamber.

13. The system of claim 1, wherein the inlet temperature is below the autoignition temperature of the fuel.

14. 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.

15. A method for oxidizing fuel, comprising:

directing a gas mixture, comprising an oxidizable fuel, to an oxidizer having a reaction chamber configured to receive and oxidize the fuel in a gradual oxidation process within the reaction chamber;

introducing water into the reaction chamber during the oxidation process, the water being at an inlet temperature lower than the internal temperature of the reaction chamber, such that the water is heated as it is introduced into the reaction chamber;

calculating an adiabatic temperature of the gas mixture;

determining when the adiabatic temperature exceeds or is equal to a flameout temperature of the gas mixture;

when the adiabatic temperature exceeds or is equal to the flameout temperature, regulating an introduction of the water such that the internal temperature within the reaction chamber is reduced; and

when the adiabatic temperature is below the flameout temperature, regulating the introduction of the water such that the internal temperature within the reaction chamber exceeds the autoignition temperature within the reaction chamber.

16. The method of claim 15, wherein the water is introduced into the reaction chamber as a liquid.

17. The method of claim 16, wherein the liquid is introduced into the reaction chamber by passing through one or more coils within the reaction chamber.

18. The method of claim 16, wherein the liquid is injected into the reaction chamber, such that the liquid mixes with the gas mixture within the reaction chamber.

19. The method of claim 15, wherein the water is introduced into the reaction chamber as a gas.

20. The method of claim 19, wherein the gas is introduced into the reaction chamber by passing the gas through one or more coils within the reaction chamber.

21. The method of claim 19, wherein the gas is injected into the reaction chamber, such that the gas mixes with the gas mixture within the reaction chamber.

22. The method of claim 15, wherein the heated water is extracted from the reaction chamber as a heated gas.

23. The method of claim 22, further comprising redirecting the heated gas into the reaction chamber, such that the heated gas mixes with the gas mixture within the reaction chamber.

24. The method 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.