GAS TURBINE PROCESS UTILIZING PURIFIED FUEL GAS

• US 3,868,817 A
• Filed: 12/27/1973
• Issued: 03/04/1975
• Est. Priority Date: 12/27/1973
• Status: Expired due to Term

• Current Assignee: Albert Brent, Charles P. Marion, James R. Muenger, Warren G. Schlinger
• Original Assignee: Albert Brent, Charles P. Marion, James R. Muenger, Warren G. Schlinger
• Inventors: Schlinger, Warren G., Muenger, James R., Marion, Charles P., Brent, Albert
• Primary Examiner(s): Husar, C. J.
• Assistant Examiner(s): Olsen, Warren
• Application Number:
  US05/428,981
• Time in Patent Office: 432 Days
• Field of Search: 60/39.12,39.46,39.02,39.05,39.52,39.18B 48/215,213,206
• US Class Current: 60/781
• CPC Class Codes: C01B 3/36 using oxygen or mixtures containing oxygen as gasifying agents
• CPC Class Codes: F02C 3/20 using a special fuel, oxidant, or dilution fluid to generate the combustion products
• CPC Class Codes: F05D 2200/262 Cosine

Abstract

Gas turbines for producing mechanical and electrical power without polluting the atmosphere are fueled by an improved clean fuel gas having a heat of combustion in the range of about 75-350 BTU/SCF and a mole ratio (CO/H2) of at least 0.30. The fuel-gas is produced by partial oxidation of a hydrocarbonaceous fuel in a free-flow noncatalytic fuel-gas generator. Feedstock to the fuelgas generator may include high ash, high sulfur, hydrocarbonaceous fuels. Pollutants are separated from the process stream of fuel gas, and a CO2- rich stream is recovered. The CO2-rich stream may be used either as a portion of the temperature moderator in the gas generator or in a noncatalytic, thermal, reverse water-gas shift reaction with hydrogen in the process fuel gas stream to increase the mole ratio (CO/H2), or for both purposes. Sensible heat in the clean fuel gas leaving the gas turbine may be recovered by superheating steam. The superheated steam may be used as the working fluid in a steam turbine used to drive an electric generator or a turbocompressor or both. At least a portion of the clean flue gas leaving the turbine may be introduced into the gas generator as a temperature moderating gas. The remainder of the clean flue gas may be safely discharged to the atmopshere without causing pollution.

Claims

1. REACTING A HYDROCARBONACEOUS FUEL WITH A FREE-OXYGEN CONTAINING GAS BY PARTIAL OXIDATION IN THE PRESENCE OF A TEMPERATURE MODERATOR SELECTED FROM THE GROUP CONSISTING OF AT LEAST A PORTION OF THE CO2-RICH GAS STREAM FROM STEP (3), AT LEAST A PORTION OF THE EXHAUST FLUE GAS FROM STEP (4), AND MIXTURES THEREOF IN THE REACTION ZONE OF A NON-CATALYTIC FREE-FLOW GAS GENERATOR AT AN AUTOGENOUS TEMPERATURE IN THE RANGE OF ABOUT 1500*FF TO 3500*F AND A PRESSURE IN THE RANGE OF ABOUT 10 TO 180 ATOMSPHERES ABSOLUTE TO PRODUCE AN EFFLUENT GAS STREAM COMPRISING MIXTURES OF H2, CO, CO2 AND H2O AND ONE OR MORE OF THE MEMBERS OF THE GROUP N2, CH4, COS, H2S AND AR, AND PARTICULATE CARBON;

AND WHEREIN THE MOLE RATIO (CO/H2) DRY BASIS OF THE EFFLUENT GAS FROM THE GENERATOR IS AT LEAST 0.30;

2. mixing a supplemental CO2-rich gas stream produced subsequently in the process with the effluent gas stream from (1) and in a free-flow thermal shift conversion zone subjecting the resulting mixed gas stream to non-catalytic thermal reverse water-gas shift reaction at a temperature of at least 1500*F., thereby increasing the mole ratio (CO/H2) dry basis of the effluent gas stream from (1);

3. The process of claim 1 further provided with the steps of compressing free-oxygen containing gas to a pressure above that in the gas generator in step (1) by means of a compressor driven by the expansion turbine in step (4) and introducing the compressed free-oxygen containing gas into said gas generator as the free-oxygen containing gas specified therein.

4. introducing the cooled effluent gas from (3) into a gas cleaning and purification zone and separately obtaining therefrom a stream of improved fuel gas comprising H2, CO, and optionally N2 and CH4;

a CO2-rich gas stream;

a slurry stream comprising particulate carbon and a liquid carrier; and

a gas stream comprising H2S and COS;

5. The process of claim 1 further provided with the steps of compressing a portion of the CO2-rich gas stream from step (3) to a pressure above that in the gas generator in step (1) by means of a compressor driven by the expansion turbine in step (4), mixing the compressed CO2-rich gas stream with the effluent gas stream from step (1), and in a free-flow thermal shift conversion zone subjecting the resulting mixed gas stream to noncatalytic thermal reverse water-gas shift reaction at a temperature of at least 1500*F. to increase the CO/H2 mole ratio to a value (dry basis) in the range of about greater than 0.3 to 6.0.

6. burning the improved stream of fuel gas from (4) with air in said combustion chamber and passing the resulting flue gas as the working fluid through said power-developing expansion turbine;

and

7. The process of claim 1 further provided with the step of passing the cooled effluent gas stream from step (2), at a pressure substantially that of said generator less ordinary line drop, through an expansion turbine located upstream from said gas turbine.

8. The process of claim 1 wherein the free-oxygen containing gas in step (1) is selected from the group consisting of air, oxygen-enriched air (more than 21 mole percent O2) and substantially pure oxygen (more than 95 mole percent O2).

9. The process of claim 1 wherein said hydrocarbonaceous fuel is a liquid hydrocarbon selected from the group consisting of liquefied petroleum gas;

petroleum distillates and residues, gasoline, naphtha, kerosine, crude petroleum, asphalt, gas oil, residual oil, tar-sand oil, shale oil, coal oil;

aromatic hydrocarbons such as benzene, toluene, xylene fractions coal tar, cycle gas oil from fluid-catalytic-cracking operation;

furfural extract of coker gas oil; and

mixtures thereof.

10. The process of claim 1 wherein said hydrocarbonaceous fuel is a gaseous hydrocarbon selected from the group consisting of methane, ethane, propane, butane, pentane, natural gas, water gas, coke-oven gas, refinery gas, acetylene tail gas, ethylene off-gas, and mixtures thereof.

11. The process of claim 1 wherein said hydrocarbonaceous fuel is an oxygenated hydrocarbonaceous organic material selected from the group consisting of carbohydrates, cellulosic materials, aldehydes, organic acids, alcohols, ketones, oxygenated fuel oil, waste liquids and by-products from chemical processes containing oxygenated hydrocarbonaceous organic materials and mixtures thereof.

12. The process of claim 1 wherein said hydrocarbonaceous fuel is a pumpable slurry of solid carbonaceous fuels selected from the group consisting of coal, particulate carbon, petroleum cokes, concentrated sewer sludge in a vaporizable carrier such as water, liquid hydrocarbon fuel and mixtures thereof.

13. The process of claim 1 further provided with the step of preheating the hydrocarbonaceous fuel to a temperature up to 1200*F. but below its cracking temperature proir to introducing said fuel into the gas generator in step (1).

14. The process of claim 1 further provided with the steps of introducing at least a portion of said steam from step (2) into a steam turbine driving a turbocompressor, compressing air in said turbocompressor, introducing said compressed air into an air separation unit in which oxygen and nitrogen are separated from the air feed, and compressing at least a portion of said oxygen and introducing same into said gas generator as at least a portion of said free-oxygen-containing gas.

15. The process of claim 14 further provided with the step of introducing at least a portion of said separated nitrogen into the gas purification zone of step (3) to aid in the separation of said streams.

16. The process of claim 1 wherein H2O is passed through burner into the reaction zone in step (1).

17. A process for the generation of power by means of a gas turbine wherein a hydrocarbonaceous fuel is gasified to produce a fuel gas which is burned in a combustion chamber to produce a flue gas which is introduced into a power-developing expansion turbine, the improvement which comprises

18. The process of claim 17 provided with the added step of compressing a portion of the exhaust flue gas leaving step (7) in a compressor driven by the steam turbine in step (7) to a pressure greater than that in the said gas generator and introducing the compressed flue gas into the gas generator in step (1) as said temperature moderating gas.

19. The process of claim 17 further provided with the step of compressing a portion of the CO2-rich gas stream from step (4) to a pressure greater than that of said gas generator and introdcing the compressed gas into the gas generator in step (1) as said temperature moderating gas.

20. The process of claim 17 further provided with the step of compressing air in a compressor driven by the expansion turbine in step (6) to a pressure greater than that in said gas generator, and introducing said cOmpressed air into the gas generator in step (1), as at least a portion of said free-oxygen containing gas.

21. The process of claim 17 further provided with the step of compressing air in a compressor driven by the expansion turbine in step (6), and introudcing said compressed air into the combustion chamber as the air specified in step (6).

22. The process of claim 17 whereby the improved fuel gas stream separated in step (4) has a Heat of Combustion in the range of about 75 to 350 BTU/SCF.

23. The process of claim 17 where the pressure in the system up through the combustion chamber in step (6) is substantially the same as that in the gas generator in step (1) less ordinary pressure drop in the line.

24. The process of claim 17 with the addition of steam to the combustion chamber in step (6).