EP0059855A1 - Combusteur catalytique pour des turbines à gaz stationnaires avec injection de carburant secondaire pour réduction de NOx - Google Patents

Combusteur catalytique pour des turbines à gaz stationnaires avec injection de carburant secondaire pour réduction de NOx Download PDF

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Publication number
EP0059855A1
EP0059855A1 EP82101110A EP82101110A EP0059855A1 EP 0059855 A1 EP0059855 A1 EP 0059855A1 EP 82101110 A EP82101110 A EP 82101110A EP 82101110 A EP82101110 A EP 82101110A EP 0059855 A1 EP0059855 A1 EP 0059855A1
Authority
EP
European Patent Office
Prior art keywords
fuel
catalytic
primary
zone
basket
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP82101110A
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German (de)
English (en)
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EP0059855B1 (fr
Inventor
Paul Walter Pillsbury
Paul Edward Scheihing
James Anthony Laurelli
Joel Lyle Toof
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CBS Corp
Original Assignee
Westinghouse Electric Corp
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Publication date
Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
Publication of EP0059855A1 publication Critical patent/EP0059855A1/fr
Application granted granted Critical
Publication of EP0059855B1 publication Critical patent/EP0059855B1/fr
Expired legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C13/00—Apparatus in which combustion takes place in the presence of catalytic material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/28—Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply
    • F23R3/34—Feeding into different combustion zones
    • F23R3/346—Feeding into different combustion zones for staged combustion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/40—Continuous combustion chambers using liquid or gaseous fuel characterised by the use of catalytic means

Definitions

  • This invention relates to stationary combustion turbines and more particularly to the implementation of catalytic combustion in such turbines to characterize the turbine operation with low NO emissions.
  • compressor discharge air is supplied at an elevated temperature to support the combustion of fuel supplied through one or more nozzles at the upstream end of multiple combustor baskets.
  • Combustion products are directed through ducting to the turbine blades.
  • the temperature of the compressor discharge air used in the fuel-air mix depends on the compression ratio of the compressor which is based on overall turbine design considerations. For any particular compressor design, the compressor discharge temperature also depends on the operating point of the turbine during the startup and load operating modes. Generally, as turbine speed or load increases, the compressor discharge air temperature increases.
  • the invention relates to a catalytic combustion system for a stationary gas turbine comprising a combustor basket having a tubular sidewall defining a primary combustion zone therein, primary nozzle means for supplying fuel for combustion in the primary zone, said combustor basket sidewall defining a secondary zone downstream from the primary zone, secondary means for injecting fuel and air into the secondary zone for mixing with the primary combustion product flow to provide a fuel-air mixture at a combustor basket outlet sufficiently mixed and heated to undergo catalytic reaction, a catalytic unit, means for supporting said catalytic unit to receive the outlet flow from said combustor basket, and means for supplying fuel to said primary nozzle means and said secondary injecting means in a predetermined coordinated manner characterized in that said basket sidewall is structured along the primary combustion zone such that the primary zone outlet cross-section is at least as great as the primary zone cross-section over the primary zone upstream from the primary zone outlet, said combustor basket including a downstream diffuser end portion having a sidewall which defines an expanding path for the
  • Figure 1 a generalized schematic representation of the preferred embodiment of the invention.
  • a turbine or generally cylindrical catalytic combustor 10 is combined with a plurality of like combustors (not shown) to supply hot motive gas to the inlet of a turbine (not shown in Figure 1) as indicated by the reference character 12.
  • the combustor 12 includes a catalytic unit 14 which preferably includes a conventional monolithic catalytic structure having substantial distributed catalytic surface area which effectively supports catalytic combustion (oxidation) of a fuel-air mixture flowing through the unit 14.
  • the catalytic structure is a honeycomb structure having its passages extending in the gas flow direction.
  • the combustor 10 includes a zone 11 into which fuel, such as oil, is injected by nozzle means 16 from a fuel valve 17 where fuel-air mixing occurs in preparation for entry into the catalytic unit 14. Proper mixing preferably entails vaporization of 80% to 90% of the injected fuel for efficient and effective catalytic reaction.
  • the fuel-air mix temperature (for example 800°F) required for catalytic reaction is higher than the temperature (for example 700°F) of the compressor discharge air supplied to the combustors from the enclosed space outside the combustor shells.
  • the deficiency in air supply temperature in typical cases is highest during startup and lower load operation.
  • a primary combustion zone 18 is accordingly provided upstream from the fuel preparation zone 11 within the combustor 10.
  • Nozzle means 20 are provided for injecting fuel from a primary fuel valve 22 into the primary combustion zone 18 where conventional flame combustion is supported by primary air" entering the zone 18 from the space within the turbine casing through openings in the combustor wall.
  • a hot gas flow is supplied to the catalytic fuel preparation zone where it can be mixed with the fuel and air mixture in the fuel preparation zone 11 to provide a heated fuel mixture at a sufficiently high temperature to enable proper catalytic unit operation.
  • the fuel injected by the nozzle means 16 for combustion in the catalytic unit is a secondary fuel flow which is mixed with secondary air and the primary combustion products which supply the preheating needed to raise the temperature of the mixture to the level needed for entry to the catalytic unit.
  • the catalytic combustion system is operated by a generally conventional analog or digital computer or digital/analog speed and load control 24 which operates the primary and secondary fuel valves 22 and 17 through conventional electropneumatic valve controls 26 and 28 respectively.
  • the control 24 is preferably arranged to operate the primary fuel system to energize the turbine through primary combustion only during startup and, after synchronization, during loading up to a predetermined load level. Thereafter, primary combustion is reduced by primary fuel cutback as secondary fuel flow is initiated by the control 24 to provide for turbine energization primarily through catalytic combustion.
  • primary combustion provides the turbine energization needed to drive the turbine operation to the point where motive gas temperatures are sufficient for sustained catalytic combustion operation.
  • FIGs 2 and 3 there is shown a structurally detailed catalytic combustion system 30 embodying the principles described for the combustor 10 of Figure 1.
  • the combustion system 30 generates hot combustion products which pass through stator vanes 31 to drive turbine blades (not shown).
  • a plurality of the combustion systems 30 are disposed about the rotor axis within a turbine casing 32 to supply the total hot gas flow needed to drive the turbine.
  • the catalytic combustor 30 includes a combustor basket 40, a catalytic unit 36 and a transition duct 38 which directs the hot gas to the annular space through which it passes to be directed against the turbine blades.
  • the combustor basket 40 is mounted on the casing 32 by bolt means 42 and preferably is provided with a primary and plural (six) secondary sidewall fuel nozzles 44 and 46. Fuel supplied through the primary nozzle 44 (readily removable for maintenance) is mixed with primary combustion support air, which enters the basket 40 through sidewall scoops 48 (or openings), and burned in a primary combustion zone 50 to provide hot gas for driving the turbine or preheating a downstream fuel-air mixture to the level required for catalytic reaction. Primary combustion support air also enters the basket 40 in this case through swirlers 52 which are disposed coaxially about the primary nozzle 44. Dilution air enters the zone 50 primarily through scoops 49.
  • the length of the primary zone 50 accordingly is sufficient to provide the space needed for primary combustion to occur followed by the space needed for mixing of the primary combustion products with dilution air.
  • the primary zone sidewall is conventionally structured from a plurality of sidewall rings which are securely held together in a telescopic arrangement by corrugated spacer bands.
  • the spacer bands thus provide an annular slot between adjacent sidewall ring members through which air is admitted to cool the internal sidewall ring surfaces.
  • the cross-section of the primary zone increases slightly in the downstream direction.
  • Primary ignition is provided by a conventional spark igniter in a tube 35 in one or more of the combustors 40.
  • Cross flame tube connectors indicated by reference character 37 are employed to ignite the other combustors 40.
  • the supplemental use of a conventional burner to produce part of the total fuel combustion in the system 30 enables compensation to be made for dropoff in catalytic activity with turbine operation time.
  • the ratio of conventional combustion to catalytic combustion is sufficient under all higher output operating conditions to achieve the needed combustion assistance without the production of an unacceptable NO penalty.
  • the resultant mix expands as it passes through an outwardly flared diffuser 56 which forms an end portion of the basket 40. It then enters a catalytic reaction element in the catalytic unit 36.
  • Proper penetration of secondary air jets into the combustor is important from the standpoint of fuel/air mixing because the jets carry the secondary fuel with them. If penetration is excessive, the center of the catalyst element receives too much fuel; if too little penetration is obtained, the edges of the catalyst receive too much fuel. For optimum mixing, the maximum penetration should be 33% of the tubular combustor diameter.
  • the diffuser 56 is employed because a smaller path diameter is needed for satisfactory fuel mixing in the combustor basket 40 as compared to the path diameter needed for catalytic combustion.
  • injection of secondary fuel into a smaller diameter basket provides improved fuel/air mixing and better fuel/air uniformity across the face of the catalyst.
  • the use of a larger basket diameter enables use of a larger catalyst diameter which results in a lower catalyst inlet velocity and produces a lower pressure drop and improved combustion efficiency.
  • the flared shape of the diffuser 56 is formed to prevent hot gas flow separation (i.e. to prevent turbulent layer formation near the diffuser wall). Back pressure from the catalyst structure provides forces needed to expand gas streamlines out to the diffuser wall and prevent turbulent layer buildup.
  • the system operates so that the residence time for the gaseous mixture (in this case, preheated to 800°F) in the secondary fuel preparation zone 54 is less than the ignition delay time from the primary zone 50. In this way, flame is contained in the primary combustion zone 50 away from the catalytic element.
  • the secondary fuel injection plane 58 is spaced from the catalyst face by a distance which is sufficient to permit proper fuel mixing (substantial uniformity across the catalyst face) and preparation for the catalyst but which is less than the critical distance which allows the fuel- air mixture to auto-ignite before it crosses the secondary zone 54 into the catalytic element. Normally, the fuel- air mixture is driven across the zone 54 within several milliseconds to avoid auto-ignition.
  • the secondary fuel nozzles 46 are supported preferably with a predetermined spacing outwardly from the combustor sidewall. In this case, the nozzles are angled for transversely directed fuel injection with a predetermined angle of spread.
  • Each nozzle 46 is connected (see Figure 5) to a tubular fuel supply line 60 which is supported coaxially within an outer tubular air line 62.
  • the air tube 62 in turn is supported by a sliding rail arrangement 64 (see Figure 4) which includes a bracket 65 attached to the sidewall of the combustor basket 40.
  • a flexible joint 69 ( Figure 3) provides for longitudinal expansion of the fuel nozzle assembly.
  • the air tube 62 is supported at its casing entry end by a mounting plate 66 which is bolted to a flange on a sleeve 70 as indicated at 68.
  • the sleeve 70 is secured suitably to the turbine casing 32 and it thus provides an opening through which the fuel nozzle assembly extends into the space within the casing 32. All secondary fuel nozzle assemblies are thus readily removable for maintenance simply by removing the bolts 68 and first sliding the tubular assembly so that mount 63 slides free of the rail bracket 65 and then continuing to slide the assembly until it is removed from the turbine casing.
  • the cooling air also atomizes the fuel to a fuel fog as it is injected through the scoops 55 into the combustor fuel preparation zone 54.
  • An additional air jet joins the nozzle flow in the scoop 55 and provides any additional air needed to achieve the desired fuel-air ratio (preferably lean) in the fuel preparation zone 54.
  • the scoop size and nozzle placement both can be varied to modify the amount of such air jet flow.
  • the diameter of the catalytic element is determined mainly by the maximum allowable reference gas velocity for complete emissions burnout at an acceptable pressure loss. Higher gas velocities require longer catalyst beds and result in higher emissions.
  • the mass transfer units required for complete emissions burnout are inversely proportional to the square root of reference velocity in laminar flow, but the effect of reference velocity on the mass transfer rate decreases with an increase in channel Reynolds number.
  • the maximum allowable reference velocity is limited in turbulent flow by the restriction of pressure losses.
  • the low limit boundary of reference velocity for the region of operability may be determined by flashback considerations in the fuel preparation zone.
  • the catalytic element includes a can within which a catalytic honeycomb structure is conventionally supported by suitable means.
  • the catalyst characteristics can be as follows:

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
EP82101110A 1981-03-05 1982-02-16 Combusteur catalytique pour des turbines à gaz stationnaires avec injection de carburant secondaire pour réduction de NOx Expired EP0059855B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US24069581A 1981-03-05 1981-03-05
US240695 1981-03-05

Publications (2)

Publication Number Publication Date
EP0059855A1 true EP0059855A1 (fr) 1982-09-15
EP0059855B1 EP0059855B1 (fr) 1985-05-22

Family

ID=22907562

Family Applications (1)

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EP82101110A Expired EP0059855B1 (fr) 1981-03-05 1982-02-16 Combusteur catalytique pour des turbines à gaz stationnaires avec injection de carburant secondaire pour réduction de NOx

Country Status (11)

Country Link
EP (1) EP0059855B1 (fr)
JP (2) JPS57161424A (fr)
AR (1) AR228640A1 (fr)
AU (1) AU557731B2 (fr)
BR (1) BR8201075A (fr)
CA (1) CA1169257A (fr)
DE (1) DE3263595D1 (fr)
IN (1) IN155701B (fr)
IT (1) IT1150246B (fr)
MX (1) MX159433A (fr)
ZA (1) ZA821005B (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU567486B2 (en) * 1982-01-05 1987-11-26 International Institute Of Cellular And Molecular Pathology Ig-minus-fc fragment reactant immunoassay
EP1114279A1 (fr) * 1998-09-18 2001-07-11 Woodward Governor Company Procede et systeme de regulation de la dynamique pour des processus a combustion catalytique et moteur a turbine a gaz y recourant
CN104583677A (zh) * 2012-05-15 2015-04-29 加热技术改良控股有限公司 用于操作液体燃料催化燃烧的催化加热器和反应器中的燃料喷射系统
US9091434B2 (en) 2008-04-18 2015-07-28 The Board Of Trustees Of The University Of Alabama Meso-scaled combustion system

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4726181A (en) * 1987-03-23 1988-02-23 Westinghouse Electric Corp. Method of reducing nox emissions from a stationary combustion turbine
US4870824A (en) * 1987-08-24 1989-10-03 Westinghouse Electric Corp. Passively cooled catalytic combustor for a stationary combustion turbine

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3797231A (en) * 1972-07-31 1974-03-19 Ford Motor Co Low emissions catalytic combustion system
US3928961A (en) * 1971-05-13 1975-12-30 Engelhard Min & Chem Catalytically-supported thermal combustion
US4072007A (en) * 1976-03-03 1978-02-07 Westinghouse Electric Corporation Gas turbine combustor employing plural catalytic stages
FR2375543A1 (fr) * 1976-12-22 1978-07-21 Engelhard Min & Chem Procede pour effectuer la combustion entretenue d'un combustible carbone
US4112675A (en) * 1975-09-16 1978-09-12 Westinghouse Electric Corp. Apparatus and method for starting a large gas turbine having a catalytic combustor
US4201046A (en) * 1977-12-27 1980-05-06 United Technologies Corporation Burner nozzle assembly for gas turbine engine

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3928961A (en) * 1971-05-13 1975-12-30 Engelhard Min & Chem Catalytically-supported thermal combustion
US3797231A (en) * 1972-07-31 1974-03-19 Ford Motor Co Low emissions catalytic combustion system
US4112675A (en) * 1975-09-16 1978-09-12 Westinghouse Electric Corp. Apparatus and method for starting a large gas turbine having a catalytic combustor
US4072007A (en) * 1976-03-03 1978-02-07 Westinghouse Electric Corporation Gas turbine combustor employing plural catalytic stages
FR2375543A1 (fr) * 1976-12-22 1978-07-21 Engelhard Min & Chem Procede pour effectuer la combustion entretenue d'un combustible carbone
US4118171A (en) * 1976-12-22 1978-10-03 Engelhard Minerals & Chemicals Corporation Method for effecting sustained combustion of carbonaceous fuel
US4201046A (en) * 1977-12-27 1980-05-06 United Technologies Corporation Burner nozzle assembly for gas turbine engine

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU567486B2 (en) * 1982-01-05 1987-11-26 International Institute Of Cellular And Molecular Pathology Ig-minus-fc fragment reactant immunoassay
EP1114279A1 (fr) * 1998-09-18 2001-07-11 Woodward Governor Company Procede et systeme de regulation de la dynamique pour des processus a combustion catalytique et moteur a turbine a gaz y recourant
EP1114279A4 (fr) * 1998-09-18 2002-04-17 Woodward Governor Co Procede et systeme de regulation de la dynamique pour des processus a combustion catalytique et moteur a turbine a gaz y recourant
US9091434B2 (en) 2008-04-18 2015-07-28 The Board Of Trustees Of The University Of Alabama Meso-scaled combustion system
CN104583677A (zh) * 2012-05-15 2015-04-29 加热技术改良控股有限公司 用于操作液体燃料催化燃烧的催化加热器和反应器中的燃料喷射系统
CN104583677B (zh) * 2012-05-15 2016-11-23 加热技术改良控股有限公司 用于操作液体燃料催化燃烧的催化加热器和反应器中的燃料喷射系统

Also Published As

Publication number Publication date
DE3263595D1 (en) 1985-06-27
IT8219962A0 (it) 1982-03-04
IN155701B (fr) 1985-02-23
ZA821005B (en) 1983-02-23
JPS6042290Y2 (ja) 1985-12-25
AU557731B2 (en) 1987-01-08
BR8201075A (pt) 1983-01-11
JPS57161424A (en) 1982-10-05
JPS6016867U (ja) 1985-02-05
CA1169257A (fr) 1984-06-19
AR228640A1 (es) 1983-03-30
IT1150246B (it) 1986-12-10
AU8049682A (en) 1982-09-09
MX159433A (es) 1989-06-01
EP0059855B1 (fr) 1985-05-22

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