Classifications

• • 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
  • 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
  • F23C13/08—Apparatus in which combustion takes place in the presence of catalytic material characterised by the 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
  • F23R3/343—Pilot flames, i.e. fuel nozzles or injectors using only a very small proportion of the total fuel to insure continuous 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
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23D—BURNERS
  • F23D2900/00—Special features of, or arrangements for burners using fluid fuels or solid fuels suspended in a carrier gas
  • F23D2900/00014—Pilot burners specially adapted for ignition of main burners in furnaces or gas turbines

Definitions

• the invention relates to a burner, in particular for a gas turbine, in which a catalytic auxiliary burner is provided for stabilizing a main burner.
• Natural gas, coal gas or some other gaseous hydrocarbon and / or hydrogen-containing mixture is provided as the fuel.
• Such a mixture or a fossil fuel in liquid form are also suitable.
• nitrogen oxides NO x are formed as particularly undesirable combustion products. In addition to sulfur dioxide, these nitrogen oxides are the main cause of the environmental problem of acid rain.
• One is therefore - also due to strict legal limit values for NO x emissions - willing to keep the NO x emissions of a burner in a gas turbine particularly low without significantly influencing the performance of the burner or the gas turbine.
• reducing the flame temperature in the burner reduces nitrogen oxide.
• water vapor is added to the fuel or compressed and preheated fresh air, or water is injected into the combustion chamber.
• Measures that reduce the burner's nitrogen oxide emissions per se are referred to as primary measures for nitrogen oxide reduction.
• a burner for generating such a pilot flame is usually a diffusion burner, which is a not insignificant source of nitrogen oxide.
• the aim is therefore to avoid any source of nitrogen oxide, however small, or at least to reduce its nitrogen oxide emission.
• the invention is therefore based on the object of specifying a burner, in particular for a gas turbine, in which the device for generating a pilot flame works particularly low in nitrogen oxide.
• a burner is provided for the combustion of a fuel, in which the fuel outlet of a catalytic auxiliary burner for stabilizing the main burner with catalytic combustion of a pilot fuel flow is provided in a flow channel in the flow direction of the fuel in a flow channel is.
• the burner uses a catalytic combustion of the pilot fuel flow to stabilize or support the main burner.
• the pilot flame required to stabilize the main burner or burners is generated by a catalytic combustion which is particularly low in nitrogen oxide.
• the catalytic auxiliary burner is central and the
• Main burners are arranged coronally. This is particularly advantageous for a homogeneous distribution of the pilot flame in the radial direction, so that the combustion of the main fuel stream can also take place on a uniform front.
• the pilot fuel flow is led to the catalytic auxiliary burner via a preforming stage.
• a lowering of the catalytic ignition temperature of the pilot fuel flow is achieved, because in the preforming stage the fuel turns into easily igniting compounds is decomposed.
• alcohols such as methanol, aldehydes and hydrogen are formed in the preforming stage, for example.
• pilot fuel stream is mixed with ambient and / or compressor air.
• NO x emissions of the pilot burner can be further reduced by setting the volume ratios of fuel / preformed fuel to ambient and / or compressor air.
• the fuel outlet of the catalytic auxiliary burner is arranged between 0.5 and 5 m in front of the fuel outlet of the main burner, this distance preferably being about 0 , Can be 75 to 2 m.
• the main burner is designed as a catalytic main burner.
• a burner like the catalytic auxiliary burner, is distinguished by comparatively low nitrogen oxide emissions.
• FIG. 2 and 4 each show a top view of a cross section through the flow channel in the burner part according to FIG. 1 and FIG. 3.
• FIGS. 1 and 2 coincides with one feature with the exemplary embodiment according to FIGS. 3 and 4.
• the explanations which now follow therefore apply mutatis mutandis to FIGS. 3 and 4.
• FIG. 1 shows a schematic representation of the burner part 2 of a gas turbine not shown here.
• the burner part 2 comprises a flow channel 4, into which a catalytic auxiliary burner 6 and a catalytic main burner 8 are installed.
• the catalytic support burner 6 and the main catalytic burner 8 are arranged rotationally symmetrically to the axis of symmetry 10 of the flow channel 4.
• the arrangement of the catalytic auxiliary burner 6 in the center of the flow channel 4 creates an outer annular space 12 and an inner central space 14.
• a fuel mixture 16, consisting of fuel gas, here natural gas, is compressed in the annular space 12 by means of the compressor part of the gas turbine (not shown here) 18, and air 20.
• a pilot fuel flow 22 flowing into the annular space 12 originally consists of the same natural gas / air-gas mixture 18, 20 which, however, is preformed in a preforming stage 24.
• the preformed pilot fuel flow 22 flowing into the support burner 6 can also be referred to as an easily igniting pilot fuel flow.
• the natural gas / air mixture 18, 20 is preformed on a noble metal-containing catalyst which, for example, has a honeycomb shape, comprises titanium dioxide as the main component and platinum and rhodium as the catalytically active components.
• the catalyst is installed in the preforming stage 24 in a manner not shown here.
• a heat exchanger can also be connected upstream of the catalyst in the preforming stage 24 in order to warm up the natural gas / air mixture 18, 20 entering the preforming stage and thus the effectiveness of the catalyst in the
• the fuel outlet of the catalytic auxiliary burner 6 is arranged in the flow direction of the fuel gas 16 at a distance d of approximately 1 m in front of the fuel outlet of the main catalytic burner 8.
• the catalytic auxiliary burner 6 comprises a honeycomb catalyst which has at least one of the substances titanium dioxide, silicon dioxide and zirconium oxide as the basic constituent.
• all noble metals and metal oxides which have a strongly oxidizing effect on the fuels mentioned are suitable as catalytically active components. These are, for example, noble metals, such as platinum, rhodium, rhenium, iridium, and metal oxides, such as. B.
• transition metal oxides vanadium oxide, tungsten oxide, molybdenum oxide, chromium oxide, copper oxide, manganese oxide and oxides of lanthanides, such as e.g. Cerium oxide.
• Metal ion exchanged zeolites and metal oxides of the spinel type can also be used.
• the pilot fuel flow 22 entering the catalytic auxiliary burner 6 is oxidized due to the catalytically active substances and burns with a pilot flame 26. Because the fuel outlet of the auxiliary burner 6 is arranged in the flow direction of the fuel gas 16 the distance d in front of the fuel outlet of the main burner 8, it is guaranteed that the main flame 28 cannot strike back into the main catalytic burner 8 or even into the areas in front of the catalytic burner 6, 8.
• the distance d is approximately 1 m in the selected exemplary embodiment.
• the catalyst material in the main burner 8 does not differ from the catalyst material of the auxiliary burner 6.
• a catalytically particularly active substance with regard to the oxidation of the hydrocarbons contained in the fuel 1% by weight of platinum and rhodium and 2% by weight of vanadium are in each case ⁇ oxide, chromium oxide and tungsten oxide provided.
• the burner exhaust gas emerging from the burner part 2 has a particularly low nitrogen oxide content because, on the one hand, the fuel 16 is burned catalytically in the main burner 8 and because the pilot flame 26 is also generated by catalytic combustion of the pilot fuel stream 22 in the auxiliary burner 6.
• diffusion burners or spin-stabilized premix burners known from the prior art can also be used as main burners.
• FIG. 2 shows a top view of the flow channel 4, in which the arrangement of the main burner 8 as a catalytically active honeycomb catalyst can be seen in a schematic representation.
• honeycomb catalysts usually have a cell number of 4 to 100 cells per inch ⁇ and have a wall thickness of the webs of 0.5 to 5 mm.
• metallic plate catalysts or, in principle, plate catalysts.
• the catalytic auxiliary burner 6 arranged centrally in the top view according to FIG. 2 is usually identical to the geometry of the catalytic main burner 8.
• FIGS. 3 and 4 show an exemplary embodiment of the invention, in which the main catalytic burner 8 recognizable from FIG. 1 and FIG. 2 is replaced by a non-catalytic main burner which has guide blades 31 as important distinguishing features. These guide vanes 31 impart a swirl to the fuel-air mixture flowing through, which stabilizes the combustion that starts in this mixture.
• the non-catalytic main burner is characterized by a particularly low operational pressure drop and by a particular simplicity of construction, which particularly recommends this main burner for use in a gas turbine. In any case, the fact that the main burner causes premix combustion is a comparatively small one NO x emissions guaranteed.
• the pilot burner 6 is also designed as a catalytic auxiliary burner 6 in the exemplary embodiment according to FIGS. 3 and 4, it is in any case not an essential source of nitrogen oxides; accordingly, the burner according to FIG. 3 and FIG. 4 is also qualified as a burner with particularly low NO x emissions.

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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)
• Gas Burners (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (1)

Family

ID=7764161

Family Applications (1)

Country Status (7)

Cited By (3)

Families Citing this family (3)

Citations (7)

Family Cites Families (2)

• 1996
  • 1996-06-11 RU RU98100357A patent/RU2149317C1/ru not_active IP Right Cessation
  • 1996-06-11 DE DE59604180T patent/DE59604180D1/de not_active Expired - Lifetime
  • 1996-06-11 EP EP96917334A patent/EP0832399B1/de not_active Revoked
  • 1996-06-11 WO PCT/DE1996/001019 patent/WO1996041991A1/de not_active Application Discontinuation
  • 1996-06-11 JP JP50249097A patent/JP4063871B2/ja not_active Expired - Fee Related
  • 1996-06-11 ES ES96917334T patent/ES2142588T3/es not_active Expired - Lifetime
  • 1996-06-12 IN IN1093CA1996 patent/IN191368B/en unknown

Patent Citations (7)

Non-Patent Citations (2)

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