WO2011010160A1 - Appareil de combustion - Google Patents

Appareil de combustion Download PDF

Info

Publication number
WO2011010160A1
WO2011010160A1 PCT/GB2010/051216 GB2010051216W WO2011010160A1 WO 2011010160 A1 WO2011010160 A1 WO 2011010160A1 GB 2010051216 W GB2010051216 W GB 2010051216W WO 2011010160 A1 WO2011010160 A1 WO 2011010160A1
Authority
WO
WIPO (PCT)
Prior art keywords
combustion
gas
burner
lance
outlet
Prior art date
Application number
PCT/GB2010/051216
Other languages
English (en)
Inventor
Gerard John Hesselmann
Angus Duncan
Original Assignee
Doosan Power Systems Limited
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Doosan Power Systems Limited filed Critical Doosan Power Systems Limited
Publication of WO2011010160A1 publication Critical patent/WO2011010160A1/fr

Links

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 
    • F23C9/00—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
    • F23C9/003—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for pulverulent fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D1/00—Burners for combustion of pulverulent fuel
    • F23D1/02—Vortex burners, e.g. for cyclone-type combustion apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
    • F23L7/00—Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
    • F23L7/007—Supplying oxygen or oxygen-enriched air
    • 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 
    • F23C2202/00—Fluegas recirculation
    • F23C2202/20—Premixing fluegas with fuel
    • 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 
    • F23C2900/00—Special features of, or arrangements for combustion apparatus using fluid fuels or solid fuels suspended in air; Combustion processes therefor
    • F23C2900/07021—Details of lances
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2201/00—Burners adapted for particulate solid or pulverulent fuels
    • F23D2201/10—Nozzle tips
    • F23D2201/101—Nozzle tips tiltable
    • 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
    • F23D2900/00006—Liquid fuel burners using pure oxygen or O2-enriched air as oxidant
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Definitions

  • the invention relates to a combustion apparatus, to a fuel burner for a combustion apparatus, and to a method of operating a fuel burner/ combustion apparatus.
  • the invention in particular relates to an apparatus and method for improving oxyfuel burner performance by controlling the mixing of oxygen and fuel using adjustable direct injection lances.
  • the oxygen required to burn the fuel is supplied via atmospheric air.
  • the combustion of the fuel in air releases the chemical energy stored in the fuel as heat, which is then transferred to the water in the boiler to generate steam.
  • the air is supplied to the boiler via burners, which are typically of low NOx design, and via overfire air ports.
  • the boiler may have one or, more typically, a number of burners and overfire air ports.
  • the burners will typically comprise a fuel stream surrounded by one or more air streams; the air streams may be swirled, the swirling air providing the stabilisation of the flame on the burner.
  • the air may be supplied individually to each burner or overfire air port via ducts, or to a group of burners or overfire air ports via a common plenum typically known as a windbox.
  • the efficiency of combustion (as indicated by the level of carbon monoxide and unburned carbon that remains after combustion is complete) and propensity for the formation of nitrogen oxides (NOx) are related to the quantity of oxygen provided and the rate of mixing of the oxidising media with the combusting fuel. Since the concentration of oxygen in air is fixed, it is necessary to adjust the overall amount of air and/or the proportion of air to the individual registers to achieve the optimum burner performance.
  • the combustion process will utilise a recycled flue gas stream to which is added upstream of the burners a pure, or nearly pure, oxygen injection stream to produce a single comburant gas which gives combustion process performance equivalent to that of conventional air firing.
  • the oxygen concentration of the comburant gas is variable, and increases with reducing flue gas recycle rate. This approach is sometimes referred to as "simulated air" firing. A proportion of oxyfuel plant is expected to retain an air firing capability.
  • a burner for a combustion apparatus comprising:
  • a primary, fuel input conduit defining an inlet for a fuel supply and an outlet for supplying fuel to a combustion site;
  • a secondary, combustion gas input conduit defining an inlet for a first gas supply and an outlet for supplying combustion gas to a
  • a first combustion gas supply means fluidly connected to an inlet of the combustion gas input conduit
  • a second combustion gas supply means adapted to supply an oxygen rich gas directly to the combustion site generally at the outlet of the combustion gas input conduit; wherein the second combustion gas supply means comprises at least one lance having an elongate portion extending along the burner in a lance elongate direction parallel to a burner centreline and an outlet portion adapted to outlet at least a part of the oxygen rich gas in a direction at an angle to the lance elongate direction.
  • oxygen rich gas is intended to cover a gas supply that includes an oxygen content by volume substantially higher than air.
  • the second gas supply comprises substantially pure oxygen.
  • the first gas supply means may be adapted to supply a first gas other than air, for example comprising a gas composition having a reduced oxygen concentration relative to air and/ or a reduced nitrogen
  • the first gas supply comprises a mixture including recycled flue gas and the first gas supply means is adapted to supply such a mixture to the combustion gas input conduit.
  • the first gas supply is not enriched with oxygen.
  • the first gas supply means comprises a supply of reduced oxygen levels.
  • a suitable combustion mixture is created by supplying an oxygen enriched second gas supply.
  • the resultant combustion mixture thus preferably comprises oxygen enriched recycled flue gas, with optional further component gases.
  • the firing mode comprises an "oxyfuel" firing mode.
  • the addition of the pure, or nearly pure, oxygen occurs neither upstream of nor within the burner, but at the burner exit.
  • a second gas supply preferably comprising pure, or nearly pure, oxygen may be directly injected into an individual burner via the second gas supply means.
  • the second gas supply means comprises at least one lance acting as a conduit for passage of the second gas supply of oxygen rich gas from a suitable source at one end of the lance to the combustion site at the other end of the lance.
  • the lance defines a gas flow conduit and with an elongate portion extending along the burner in a lance elongate direction parallel to a burner centreline axis.
  • the lance directs at least some of the oxygen rich gas off axis at the point of outlet (that is, in a direction at an angle to the parallel with the burner centreline axis).
  • the output of such a lance is thus asymmetric and off-axial to the axial centerline longitudinal direction in the burner. This makes the injected supply directional which is a key aspect of the control of the present invention.
  • the lance is further adapted such that the off-axis injection direction is variable dynamically during use, most conveniently at least in that the lance is rotatable about an elongate axis. This changes the injection direction of the lance in simple manner.
  • the lance may also be
  • the flow rate into a lance may be variable.
  • the point at which the oxygen rich gas and the fuel carrying streams intersect, and the level of swirl imparted by the angled oxygen streams, can both be adjusted.
  • the rotation of a lance, and especially of an array of lances as a group or individually, therefore provides the ability to control the rate at which the oxygen rich gas mixes with the fuel and therefore the rate of combustion and heat release along the path of the flame. It is the asymmetrical nature of the lance outlet and the consequent off-axis injection direction in combination with the ability at least to rotate the lance to change the directionality of the off-axis outlet flow that enables the burner to achieve this controlled variability in the oxyfuel process.
  • the invention is intended to encompass a burner having a lance with an outlet portion that is adapted to outlet at least some of the oxygen rich gas in a gas injection direction at an angle to the lance elongate direction. So long as a lance does this, the required directionality of injection is obtained. In particular the invention does not preclude the use of lance(s) that also outlet at least some of the oxygen rich gas in a gas injection direction parallel to the lance elongate direction and/ or the use of directional and non-directional lances in the same burner.
  • the lance in particular may be so adapted by provision of asymmetrically arrayed outlet aperture(s), asymmetrically configured outlet portion structure(s) or combinations thereof.
  • a lance outlet portion may define a conduit portion in deviating from the lance elongate direction. In this way, the part of the lance proximal the injection site is itself diverted off-axis into a gas injection direction at an angle to the lance elongate direction.
  • one or more outlet apertures may be provided on an outlet portion end face, which end face is at an angle to the perpendicular to the lance elongate direction.
  • the outlet aperture(s) tend to outlet gas in a manner which is asymmetrically off-axis in an injection direction at an angle to the lance elongate direction.
  • one or more outlet apertures may be provided on a wall of the outlet portion upstream of an end face. Such aperture(s) may be asymmetrically arrayed to provide injection of at least a part of the gas flow in a manner which is asymmetrically off-axis.
  • the outlet portion will feature one or more outlet apertures which are asymmetrically structured and/ or located and/ or directed in such manner as to create such asymmetric off-axial outlet flow.
  • the end portion of the lance will feature one or more outlet holes on a sloped end face (a face deviating from a direction perpendicular to the lance elongate direction) plus, optionally, further holes along the lance length.
  • the size of the holes may be the same or different.
  • Such a configuration means the lance itself can have a simple elongate structure disposed to lie parallel to the burner centreline axis but still generate the required asymmetric injection at the oxygen rich gas injection location.
  • the second gas supply means comprises a plurality of lances arranged around the fuel stream defined by the primary conduit.
  • the second gas supply means comprises a plurality of lances arranged around the fuel stream defined by the primary conduit in generally evenly spaced manner.
  • the second gas supply means comprises a plurality of lances arranged around the fuel stream defined by the primary conduit
  • each lance has an independently adjustable gas supply and/ or is independently directionally adjustable (for example, being independently rotatable and or translatable) to control the fuel / oxygen mixing location and intensity.
  • the first gas supply has a similarly independently controllable adjustable gas supply with respect to an individual burner or burner conduit register to provide the balancing inert mass of the first gas to moderate the flame temperature.
  • the invention provides a means of optimising the combustion process with regard to combustion efficiency, emissions, and flue gas recycle rate within oxyfuel technology.
  • the resultant mixture of combustion gas supplied to the combustion site by a burner in accordance with the invention may have any proportion of oxygen capable of supporting combustion at the first site.
  • the resultant mixture has a proportion of oxygen which generally gives combustion process performance equivalent to that achieved with air, for example being around 20 to 50%. That is, the firing mode comprises a "simulated air" oxyfuel firing mode
  • the implementation of the invention leads to the creation of an "advanced oxyfuel burner" in particular based on the use of "simulated air”.
  • a further gas supply means is adapted to supply gas
  • both of the first combustion gas supply means and the further gas supply means are adapted to supply a mixture including recycled flue gas, for example in that both are fluidly linked to a recycled flue gas supply means.
  • the further gas supply means comprises a supply of a primary flue gas recycle (PFGR) stream
  • the first combustion gas supply means comprises a supply of a secondary flue gas recycle (SFGR) stream in familiar manner.
  • PFGR primary flue gas recycle
  • SFGR secondary flue gas recycle
  • the PFGR stream is enriched by oxygen upstream of the burner.
  • the SFGR stream is not enriched by oxygen upstream of the burner, but by the oxygen supply at the burner exit.
  • the burner may comprise further fluidly independent combustion gas input conduits, for example comprising additional tertiary or higher order input conduits, fluidly connected to additional gas supply means for supplying combustion gas to a combustion site defined by the burner, for example directly to the burner or otherwise to a combustion apparatus in which the burner is located.
  • additional gas supply means for supplying combustion gas to such additional tertiary or higher order input conduits are adapted to supply a mixture including recycled flue gas, for example in that they are fluidly linked to a recycled flue gas supply means.
  • the additional gas supply means comprises a supply of a tertiary (or higher order) flue gas recycle stream.
  • the stream is enriched by oxygen upstream of the burner, for example to approximate simulated air concentrations.
  • a primary fuel input conduit may extend along a burner, a secondary combustion gas input conduit may be disposed outwardly of and for example annularly arrayed about the primary fuel input conduit, and higher order combustion gas input conduits, where present, may be disposed outwardly of and for example annularly arrayed about the secondary input conduit in familiar manner.
  • the primary input conduit may be a central conduit extending generally axially along the burner, for example on a burner centreline.
  • the primary input conduit may itself be disposed about a central conduit, for example annularly, with the central conduit serving another purpose.
  • the primary input conduit is still preferably nearer to the centre line than the secondary and higher order conduits, but the primary stream does not necessarily flow along the centreline itself.
  • a conduit may include suitable swirl generation structures to impart an axial swirl to a gas supply therein.
  • the burner comprises:
  • an axially extending primary fuel input conduit defining an inlet for a fuel supply and an outlet for supplying fuel to a combustion site, and having a primary recycled flue gas supply means to supply recycled flue gas to the inlet;
  • a secondary combustion gas input conduit disposed outwardly of and for example annularly surrounding the primary fuel input conduit, defining an inlet for a gas supply and an outlet for supplying gas to a combustion site, and having a secondary recycled flue gas supply means fluidly connected to the inlet, and a plurality of oxygen rich gas supply means adapted to supply an oxygen rich gas directly to the combustion site generally at the outlet arrayed around the fuel stream, wherein the second combustion gas supply means comprises at least one lance having an elongate portion extending along the burner in a lance elongate direction parallel to a burner centreline and an outlet portion adapted to outlet the oxygen rich gas in a direction at an angle to the lance elongate direction; and further preferably
  • a tertiary combustion gas input conduit disposed outwardly of and for example annularly surrounding the primary and secondary conduits, defining an inlet for a gas supply and an outlet for supplying combustion gas to a combustion site, and having a tertiary recycled flue gas supply means fluidly connected to the inlet.
  • the axially extending primary fuel input conduit preferably extend along a burner axial direction about the burner centreline.
  • the primary conduit may comprise a central cylinder.
  • the primary conduit may comprise an annular conduit disposed around a central cylinder symmetrically about the burner centreline.
  • the gas supply means includes varying means, such as a baffle or valve means, for varying the proportion of gas supplied to one or both or all where applicable of the fuel input conduit and the secondary and higher order combustion gas input conduits.
  • a further oxygen rich gas supply means is provided to supply oxygen rich gas into the primary and/ or tertiary recycled flue gas supply upstream of the burner.
  • a combustion apparatus comprising:
  • At least one and preferably a plurality of burners as hereinbefore described located so as to define combustion sites within the combustion chamber.
  • the combustion apparatus comprises a boiler for generating steam.
  • the fuel used is coal, most preferably pulverised coal.
  • the combustion apparatus includes a flue gas recirculation conduit.
  • the flue gas recirculation conduit is fluidly connected to a flue gas supply means and/ or to at least one of the primary fuel input conduit and the secondary and/ or higher order combustion gas input conduits such that a mixture including flue gas may be supplied to the combustion chamber.
  • the flue gas recirculation conduit is fluidly connected to both of the fuel input conduit and the/ each
  • the injection direction is controlled at least in that the lance is rotatable about an elongate axis.
  • the lance may also be translatable longitudinally.
  • the flow rate into a lance may be variable.
  • the fuel is entrained in the first combustion gas, and the method enable the point at which the oxygen rich gas and the fuel carrying streams intersect, and the level of swirl imparted by the angled oxygen streams, to be adjusted in simple and convenient manner.
  • the combustion site generally at an outlet of the combustion gas input conduit; the combustion gas mixture comprising a mixture of the first gas and the second gas being formed at the outlet of the combustion gas input conduit.
  • the first gas comprises a composition having a reduced oxygen concentration relative to air and/ or a reduced nitrogen concentration relative to air.
  • the first gas supply comprises a mixture including recycled flue gas.
  • the first gas is not enriched with oxygen.
  • a suitable mixture is created rather by supplying an oxygen enriched and for example substantially pure oxygen second gas directly at the burner exit.
  • combustion gases are supplied to the
  • combustion site via primary, secondary and where applicable additional supply streams, in such manner that the resultant mixture has a proportion of oxygen that produces combustion process performance equivalent to that achieved with air, for example being around 20 to 50%.
  • Figure 1 is a schematic of a conventional air firing burner
  • FIG. 2 is a schematic of the oxyfuel process
  • Figure 3 is a schematic of a modified burner embodying the principles of the invention
  • Figure 4 is a close up view of alternative arrangements of lance outlet for use in the modified burner of figure 3.
  • Figure 1 is a schematic of an air firing burner of conventional design.
  • Figure 2 is a schematic of the oxyfuel process into which either a burner of conventional design such as illustrated in figure 1 or a burner in
  • the combustion air containing the required oxygen to burn the fuel
  • FD fan forced draught fan
  • the primary air (PA) which conveys the coal
  • SA secondary air
  • TA tertiary air
  • specific burner designs may have fewer or more air streams.
  • the primary air (PA) stream follows the burner axis (11 ) and the secondary air (SA), and the tertiary air (TA) streams are axially directed in ducts concentrically therearound.
  • the burner (1 ) is fired through an outlet in a furnace wall (FW).
  • the primary air stream is in a central conduit.
  • the invention is not limited to such arrangements.
  • One alternative design option involves moving the primary air (or PFGR/Oxygen/Fuel mix) to a conduit annularly parallel to the central line, but with a central cylinder along the axis used for other purposes (core air and/or for oil/gas igniters). In this case, the primary stream would still be nearer the centre line than the secondary and tertiary streams, but wouldn't flow along the actual centerline.
  • Dampers (3) control the division of the air between the secondary and tertiary streams (SA, TA).
  • SA, TA secondary and tertiary air streams
  • the secondary and tertiary air streams may be swirled, and the extent of swirl may be adjustable.
  • Swirl devices (5) are provided downstream of the dampers for this purpose. Optimisation of the burner with respect to combustion efficiency, emissions, and flame stability is achieved by variation of the total quantity of the air supplied to the burner, the division of the air between the various streams, and the level of swirl applied.
  • flue gas is recycled to the coal pulverising mill (21 ) (primary flue gas recycle, or PFGR) and to the windbox (23) containing the burners (not specifically shown in figure 2) (secondary flue gas recycle, or SFGR) by means of dedicated fans (respectively the primary flue gas recycle fan 25 and the secondary flue gas recycle fan 27).
  • the composition of the recycled flue gas is related to the combustion process, but the stream extracted from the boiler exit will contain low levels of oxygen, typically less than 5% by volume, and insufficient to support combustion. Pure, or nearly pure, oxygen is introduced into the PFGR and SFGR streams to provide the oxidant required to combust the fuel.
  • the composition of the PFGR and SFGR streams will depend upon the detailed implementation of the oxyfuel technology, but typically the PFGR will contain around 20 to 25% by volume of oxygen or higher, whereas the SFGR will contain a significantly higher oxygen
  • concentration for example 25 to 50%.
  • concentration levels will be dependant upon a number of factors including the overall furnace stoichiometry, the quantity of flue gas that is recycled to the boiler, the amount of combustion generated moisture that is removed from the recycle stream, the amount of air that leaks into the process, etc.
  • the streams supply burners (not specifically shown) via the windbox (23) to fire the furnace/ boiler (31 ) in generally known manner, with flue gases being drawn off via a particulate removal system (33) to remove solids (ash, etc, 34) and drawn by means of an ID fan (35) to a stack or capture stage (37) as will be familiar.
  • FIG. 3 is a schematic of an example embodiment of oxyfuel burner (41 ) in accordance with the invention. This is suitable for incorporation into a general oxyfuel process such as, but not limited to, the process
  • the addition of the pure, or nearly pure, oxygen occurs neither upstream nor within the burner, but at the burner exit.
  • coal is transported with primary flue gas recycle (PFGR) along the burner centreline axis (51 ).
  • PFGR primary flue gas recycle
  • the oxygen concentration in this stream may typically be enriched to an oxygen level equal to or less than 21 % by volume, or some other value.
  • a secondary annular register (44) carries a proportion of secondary flue gas recycle (SFGR) to which no additional oxygen has been supplied. Furthermore the secondary annulus accommodates a series of oxygen injection lances (45) spaced around the circumference of this annulus for the direct introduction of oxygen at the confluence of the primary and secondary streams. The main part of the length of each lance (45) extends axially parallel to the burner centerline axis and along the secondary annulus.
  • SFGR secondary flue gas recycle
  • Each lance has an outlet formation at the end portion proximal the confluence of the primary and secondary streams which is so configured as to direct at least some of the outlet flow away from the axial direction (that is, the lance elongate direction parallel to the burner centerline axis).
  • the end portion of the lance will feature one or more outlet holes which are asymmetrically structured and/ or located and/ or directed in such manner as to create such asymmetric off-axial outlet flow.
  • the end portion of the lance will feature one or more outlet holes on a sloped face (a face deviating from a direction perpendicular to the lance elongate direction) plus, optionally, further holes along the lance length.
  • the size of the holes may be the same or different.
  • Each lance will have the capability for it to be rotated; by this means the point at which the oxygen and fuel streams intersect, and the level of swirl imparted by the angled oxygen streams, can be adjusted.
  • the rotation of each lance as a group or individually, therefore provides the ability to control the rate at which the oxygen mixes with the coal and therefore the rate of combustion and heat release along the path of the flame. It is the asymmetrically acting outlets acting such as to create asymmetric off-axial outlet flow in combination with the ability to rotate the lance to change the directionality of the asymmetric off-axial outlet flow that enables the burner to achieve this controlled variability in the oxyfuel process.
  • a tertiary annulus On the outside of the secondary annulus is a tertiary annulus (46).
  • the tertiary annulus contains a means of imparting a swirl on the flow in the form of a swirl device (49), introduces the remaining SFGR to the flame and provides ballast and a further means of flame temperature control.
  • the swirl device (49) in the tertiary annulus (46) will have the capability to vary the level of swirl imparted.
  • Figure 4a is merely an enlargement of the end of the lance in figure 3.
  • the end face of the lance is a single bevel (a face deviating from a direction perpendicular to the lance elongate direction).
  • a simple aperture in the face thus generates directional flow.
  • Figure 4b illustrates a more complex end structure with more than one face.
  • at least one face slopes from a direction perpendicular to the lance elongate direction to create directional flow.
  • this simple schematic is merely illustrative of alternatives which could have multiple faces at multiple angles.
  • Figure 4c the end portion of the lance itself deviates from an axial direction. In such a case even a simple aperture in a perpendicular face generates an off-axis outlet flow.
  • Combinations of such arrangements, optionally with further aperture outlets in the elongate lance wall proximal the end face, and of any other arrangements producing directional off-axis outlet flow, can be considered without departing from the principles of lance design exploited by the invention.
  • the figures show planar faces
  • faces are concave or convex
  • faces are shown for simplicity with a single aperture, there are likely in practice to be plural arrays of apertures in angled faces and/ or cylinder walls in the manner of a pepperpot.
  • Arrangements of aperture and end structure may be such that some flow is off-axis and some is axial.
  • axial injection lances may also be provided. The condition for the invention is satisfied so long as there is at least some off-axis flow the direction of which can be affected by rotation of the asymmetric lances.
  • a fraction of the pure, or nearly pure, oxygen is additionally supplied upstream of the burner to increase the oxidant concentration to a level higher than that exiting the boiler, but not sufficient to supply the required oxidant to completely combust the fuel.
  • a second variation of this invention there may be supplemental addition of pure or nearly pure oxygen to the tertiary annulus upstream of the swirl generation device.
  • the amount of pure or nearly pure oxygen supplied to an individual burner will be controlled, so as to allow the biasing of the stoichiometry between burners to optimize the overall system performance with regard to combustion efficiency, emissions, flame stability, and gas composition at the furnace walls.
  • the invention provides a number of potential advantages including some or all of the following.
  • the mixing point of the injected oxygen stream with the fuel stream can be controlled by the use of the directional (for example, in the embodiment, the chisel-faced) injection lances and variable swirl recycled flue gas.
  • the mixing point of the injected oxygen and fuel can further be controlled by the rotation of the injection lances.
  • the oxygen flow to individual burners can be controlled by adjusting the supply to each burner's injection lances, thereby allowing the biasing of stoichiometry between burners.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Pre-Mixing And Non-Premixing Gas Burner (AREA)

Abstract

L'invention porte sur un brûleur pour un appareil de combustion, sur un appareil de combustion comprenant de tels brûleurs et sur un procédé de fonctionnement de ceux-ci. Le brûleur comprend : une conduite primaire d'entrée de combustible délimitant une entrée pour une alimentation en combustible et une sortie pour alimenter un site de combustion en combustible; une conduite secondaire d'entrée de gaz de combustion délimitant une entrée pour une première alimentation en gaz et une sortie pour alimenter un site de combustion en gaz de combustion; un premier moyen d'alimentation en gaz de combustion en communication fluidique avec une entrée de la conduite d'entrée de gaz de combustion; et un second moyen d'alimentation en gaz de combustion conçu pour alimenter directement le site de combustion en un gaz riche en oxygène généralement à la sortie de la conduite d'entrée de gaz de combustion. Le second moyen d'alimentation en gaz de combustion comprend au moins une lance ayant une partie allongée s'étendant le long du brûleur dans une direction allongée de lance parallèle à un axe de brûleur et une partie de sortie conçue pour faire sortir le gaz riche en oxygène dans une direction à un angle par rapport à la direction allongée de la lance pour ajuster le point auquel les premier et second courants de gaz se croisent. Le premier gaz est de préférence du gaz effluent recyclé et le second gaz est de préférence de l'oxygène pratiquement pur.
PCT/GB2010/051216 2009-07-23 2010-07-23 Appareil de combustion WO2011010160A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB0912770.5A GB0912770D0 (en) 2009-07-23 2009-07-23 Combustion apparatus
GB0912770.5 2009-07-23

Publications (1)

Publication Number Publication Date
WO2011010160A1 true WO2011010160A1 (fr) 2011-01-27

Family

ID=41058384

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2010/051216 WO2011010160A1 (fr) 2009-07-23 2010-07-23 Appareil de combustion

Country Status (2)

Country Link
GB (1) GB0912770D0 (fr)
WO (1) WO2011010160A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2500640A1 (fr) * 2011-03-16 2012-09-19 L'AIR LIQUIDE, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Procédé de combustion à faible NOx et brûleur correspondant
EP2926891A1 (fr) * 2013-01-28 2015-10-07 Alstom Technology Ltd Grille de distribution et de mélange de fluide pour mélanger des gaz

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0633428A1 (fr) * 1993-07-08 1995-01-11 ROLLS-ROYCE POWER ENGINEERING plc Ajutage d'air et de combustible/air à faible taux de NOx
WO2003098105A1 (fr) * 2002-05-15 2003-11-27 Praxair Technology, Inc. Combustion avec teneur réduite en carbone dans la cendre
US7028622B2 (en) * 2003-04-04 2006-04-18 Maxon Corporation Apparatus for burning pulverized solid fuels with oxygen
WO2008141412A1 (fr) * 2007-05-18 2008-11-27 Her Majesty The Queen In Right Of Canada As Represented By The Minister Of Natural Resources Procédé de combustion de charbon à l'aide d'oxygène dans un courant de gaz de combustion recyclé pour une capture de dioxyde de carbone

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0633428A1 (fr) * 1993-07-08 1995-01-11 ROLLS-ROYCE POWER ENGINEERING plc Ajutage d'air et de combustible/air à faible taux de NOx
WO2003098105A1 (fr) * 2002-05-15 2003-11-27 Praxair Technology, Inc. Combustion avec teneur réduite en carbone dans la cendre
US7028622B2 (en) * 2003-04-04 2006-04-18 Maxon Corporation Apparatus for burning pulverized solid fuels with oxygen
WO2008141412A1 (fr) * 2007-05-18 2008-11-27 Her Majesty The Queen In Right Of Canada As Represented By The Minister Of Natural Resources Procédé de combustion de charbon à l'aide d'oxygène dans un courant de gaz de combustion recyclé pour une capture de dioxyde de carbone

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2500640A1 (fr) * 2011-03-16 2012-09-19 L'AIR LIQUIDE, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Procédé de combustion à faible NOx et brûleur correspondant
WO2012123382A1 (fr) * 2011-03-16 2012-09-20 L'air Liquide Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Procédé de combustion à faible émission d'oxyde d'azote et brûleur correspondant
US9447969B2 (en) 2011-03-16 2016-09-20 L'Air Liquide Société Anonyme Pour L'Étude Et L'Exploitation Des Procedes Georges Claude Low NOx combustion process and burner therefor
EP2926891A1 (fr) * 2013-01-28 2015-10-07 Alstom Technology Ltd Grille de distribution et de mélange de fluide pour mélanger des gaz
US9518734B2 (en) 2013-01-28 2016-12-13 General Electric Technology Gmbh Fluid distribution and mixing grid for mixing gases

Also Published As

Publication number Publication date
GB0912770D0 (en) 2009-08-26

Similar Documents

Publication Publication Date Title
KR100709849B1 (ko) 농축된 석탄 스트림의 ＮＯｘ 감소성 연소 방법
EP2518404B1 (fr) Brûleur et chaudière avec un tel bruleur
AU2003237815B2 (en) Low nox combustion
CA2653890C (fr) Procede et dispositif pour combustion etagee d'air et de combustible
AU2011310173B2 (en) Combustion system and method for operating same
US7430970B2 (en) Burner with center air jet
JPH0926112A (ja) 微粉炭バーナ
JPWO2012114370A1 (ja) 燃焼装置
PL184438B1 (pl) Sposób sterowania palnikiem z uwarstwionym promieniowo jądrem płomienia
WO2011010160A1 (fr) Appareil de combustion
US20230213185A1 (en) Combustion system for a boiler with fuel stream distribution means in a burner and method of combustion
JP2012215364A (ja) ボイラ及びボイラの運転方法
CA2805689C (fr) Appareil de combustion
JP6732960B2 (ja) 燃料を燃焼させる方法及びボイラー
JP5032071B2 (ja) 中心空気噴出口を有するバーナー
CA2556822C (fr) Bruleur avec jet d'air centralise
JP5443525B2 (ja) 中心空気ジェットバーナーにおけるｎｏｘ排出削減方法
AU2006203560B2 (en) Burner with center air jet
EP2051005B1 (fr) Brûleur à jet d'air central
KR101311008B1 (ko) 중앙 공기제트 버너 및 연소방법
KR20190023829A (ko) 메인노즐을 개선한 저 질소산화물 연소기
MXPA06009338A (es) Quemador con chorro de aire central.

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 10742229

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 10742229

Country of ref document: EP

Kind code of ref document: A1