CN218914919U - Low-emission high-speed combustor and flameless combustion device - Google Patents

Abstract

The utility model discloses a low-emission high-speed combustor and a flameless combustion device; the low-emission high-speed burner is characterized in that a primary axial air inlet is formed in the inner side of the flame holder, and a secondary axial air inlet is formed in the outer side of the flame holder, so that air flow conveyed by the air conveying channel enters the flame holder in a multi-way manner and is subjected to staged combustion with air-fuel premixed air flow discharged by the air-fuel premixing device, and generation of NOx is better inhibited; and the premixed flame burns fast in the flame tube with the contracted flame nozzle, and the gas expansion is caused by the high temperature to generate certain back pressure in the flame tube, and the back pressure drives the flame to jet from the flame nozzle at high speed, so that the smoke recirculation combustion in the furnace is enhanced, the generation of NOx and CO is inhibited, the fuel gas is well combusted, the emission of nitrogen oxides and combustion particles is reduced, and the use effect is good.

Description

Low-emission high-speed combustor and flameless combustion device

Technical Field

The utility model belongs to the technical field of combustors, and particularly relates to a low-emission high-speed combustor and a flameless combustion device.

Background

Industrial heating furnaces for high temperature heating and melting applications, such as melting furnaces, industrial heating or heat treatment kilns, ceramic kilns and the like, often have corresponding requirements on the flame speed of a burner due to process requirements, and the traditional high-speed burner has a simple gas and air premixing structure, and has many defects, such as insufficient combustion of gas fuel, low gas regulation ratio, poor flame stability, high content of discharged nitrogen oxides and combustion particles.

Disclosure of Invention

The utility model aims to solve the problems of insufficient fuel combustion and high emission content of nitrogen oxides and combustion particles in the existing burner, and provides a low-emission high-speed burner for increasing flame speed and realizing low emission of nitrogen oxides and combustion particles by gas staged combustion.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

a low emission high speed burner comprising: the burner comprises a burner body, a gas input device, an air-fuel premixing device, a flame holder and a flame tube.

The burner body is provided with a gas conduit, an air conveying passage and an air input port communicated with the air conveying passage, wherein the air conveying passage is arranged on the outer side of the gas conduit along the axial direction in a surrounding manner.

The gas input device is connected to the upstream end of the gas conduit and is provided with a gas input port communicated with the gas conduit.

The air-fuel premixing device is provided with an air-fuel premixing cavity and a premixing air main nozzle, wherein the air-fuel premixing cavity is respectively communicated with the gas guide pipe and the air conveying channel, and the premixing air main nozzle is communicated with the air-fuel premixing cavity.

The flame holder is provided with a flame stabilizing cavity communicated with the premixed gas main nozzle, a plurality of primary axial air inlet ports communicated with the flame stabilizing cavity, a plurality of secondary axial air inlet ports positioned at the outer side of the flame holder and communicated with the air conveying channel, and a premixed flame nozzle which is positioned at the downstream end of the flame holder and circumferentially provided with a plurality of wave-shaped structures, wherein the secondary axial air inlet ports are positioned between adjacent lobe-shaped structures.

And the flame tube is positioned at the downstream end of the burner body and is provided with a flame nozzle with a gradually narrowed caliber communicated with the flame stabilizing cavity.

Compared with the prior art, the low-emission high-speed combustor has the advantages that the primary axial air inlet is formed in the inner side of the flame holder, and the secondary axial air inlet is formed in the outer side of the flame holder, so that air flow conveyed by the air conveying channel enters the flame holder in a multi-way manner and is subjected to staged combustion with air-fuel premixed air flow discharged by the air-fuel premixing device, and the full combustion reaction of the low-emission high-speed combustor can better inhibit NOx generation; the secondary axial air inlet is arranged between the adjacent lobe-shaped structures, so that effective mixing of air flow generated by the secondary axial air inlet and premixed flame generated by the premixed flame nozzle is enhanced, a plurality of relatively complex premixed flame vortex air flows are formed between the outlets of the lobe-shaped structures and the lips of the premixed flame nozzle, the secondary axial air inlet becomes a reliable flame stabilizing structure for secondary combustion of the premixed flame, and the premixed flame vortex air flows form conical expanding flames under the action of centrifugal force, so that the air sprayed by the secondary axial air inlet is better mixed and combusted with air sprayed by the secondary axial air inlet. And the premixed flame burns fast in the flame tube with the contracted flame nozzle, and the gas expansion is caused by the high temperature to generate certain back pressure in the flame tube, and the back pressure drives the flame to jet from the flame nozzle at high speed, so that the smoke recirculation combustion in the furnace is enhanced, the generation of NOx and CO is inhibited, the fuel gas is well combusted, the emission of nitrogen oxides and combustion particles is reduced, and the use effect is good.

Further, the flame nozzle is a butterfly nozzle with a flat middle part and caliber increasing along the outside of two adjacent sides; through setting up like this, through adjusting spout length direction's gas flow distribution, obtain more even flat flame for the flame has better heating performance, simultaneously owing to have bigger contact surface area with the stove gas, can improve the injection and the entrainment ability of flame, and make the interior flue gas of stove dispel the heat more fast, the ability of restraining NOx and generating is stronger.

Further, the flame holder is also provided with a plurality of radial air inlets and a plurality of tangential air inlets which are communicated with the flame holding cavity, the plurality of primary axial air inlets and the premixed gas main nozzle are arranged in the same direction and surround the outer side of the central axis of the flame holder, the plurality of radial air inlets are arranged around the outer side of the flame holder along the radial direction, and the plurality of tangential air inlets are arranged around the outer side of the flame holder and are arranged in a relatively inclined way along the radial direction; through the arrangement, the primary axial air inlet, the radial air inlet and the tangential air inlet are arranged in the flame stabilizing cavity, so that three-dimensional and crossed net-shaped jet structures are formed in the flame stabilizer by air flows with three different angles, directions and diameters and air-fuel premixed air flows, and innumerable vortexes with different dimensions, momentum and directions can be formed, so that possible residence points of innumerable flames are generated, and the flame stability, the flame regulation ratio and the combustion intensity of the burner are greatly improved.

Further, the air-fuel premixing device is also provided with a plurality of premixed gas radial flame stabilizing nozzles, the premixed gas main nozzle is arranged at the downstream end of the air-fuel premixing device along the axial direction, and the plurality of premixed gas radial flame stabilizing nozzles are annularly arranged at the outer side of the premixed gas main nozzle along the radial direction and are arranged in the flame stabilizing cavity; by the arrangement, the air-fuel premixing auxiliary air flow generated by the premixing air radial flame stabilizing nozzle is matched with the primary air jet generated by the primary air axial input port at the upstream part of the flame stabilizer to form a plurality of stable ignition sources, so that the flame stability of the combustor is improved.

Further, a gas nozzle is arranged at the downstream end of the gas conduit, an axial premixing gas inlet matched with the gas nozzle and a radial premixing air inlet communicated with the air conveying channel are arranged at the upstream end of the air-fuel premixing device; through the arrangement, a plurality of radial premixing air inlets in the air-fuel premixing device are used for premixing fuel gas input by the axial premixing fuel gas inlets from a plurality of different directions and angles, and the mixing effect of air and fuel gas is good.

Further, the plurality of tangential air inlet openings are arranged at the same inclination angle along the radial direction; through the arrangement, the air flow input by the tangential air inlet cuts and slows down the air-fuel premixed jet flow input by the premixed air main nozzle and simultaneously pushes the air-fuel premixed jet flow to rotate, the swirl flame is subjected to centrifugal force action at the outlet of the flame holder to form conical expanded flame, and better conditions are created for mixed combustion with the air flow input by the secondary axial air inlet.

Or further, the plurality of tangential air inlet openings are arranged at different oblique angles in the radial direction; through the arrangement, the air jet flow which is convenient to generate forms a plurality of flame stabilizing ignition points which are not at the same plane height with the gas jet flow which is generated by the gas jet, so that the flame stabilizing burner has larger gas regulation ratio, and can fully burn the gas when the gas flow of the gas jet is smaller, thereby having good use effect.

Further, the flame ion probe and the igniter are arranged in the flame stabilizer; the flame stabilizer is characterized in that a flame rectifying tube is sleeved on the outer side of the downstream end of the flame stabilizer, and the flame tube is sleeved on the outer sides of the flame rectifying tube and the downstream end of the burner body.

Another object of the present utility model is to provide a flameless combustion device using the low-emission high-speed burner, which comprises a flameless burner and the low-emission high-speed burner, wherein the flameless burner comprises a flameless gas combustion pipe, a flameless gas inlet provided at an input end of the flameless gas combustion pipe, and a flameless gas combustion nozzle provided at an output end of the flameless gas combustion pipe. With this arrangement, since a certain critical furnace temperature condition (typically 750 ℃) is required to operate the flameless combustion mode, it is not possible to operate below the critical furnace temperature condition, and other combustion modes must be used. The low-emission high-speed burner has excellent low-nitrogen performance in a low-temperature state, so that the low-nitrogen burner can be combined with a flameless burner to realize the aim of ultralow nitrogen in the whole process from low-temperature start to high-temperature operation.

Further, the flameless burner is provided with at least two flameless burners, and is annularly arranged on the outer side of the low-emission high-speed burner, and one side of the flameless gas combustion tube close to the flameless gas combustion nozzle is obliquely arranged along one side of the flame nozzle of the low-emission high-speed burner. By this arrangement, when the furnace rises above the critical furnace temperature condition, the gas supply to the low-emission high-speed burner is turned off, and the flame tube is used only as air transportation. When the gas supply of the flameless burner is opened, the gas injection speed is not lower than 80m/s, the flameless burner and the low-emission high-speed burner are arranged at an opposite included angle, so that gas jet and air jet generated by the flameless burner and the low-emission high-speed burner are mutually attracted and fused at a preset position, and simultaneously, the high-speed gas jet has ERG effect on the strong entrainment capacity of inert smoke, and NOx generation is further effectively inhibited.

Drawings

FIG. 1 is a schematic view of a low emission high speed combustor

FIG. 2 is a side view of a low emission high speed combustor

FIG. 3 is a cross-sectional view of a low emission high speed combustor

FIG. 4 is a cross-sectional view of a low emission high speed combustor removal rocket barrel

FIG. 5 is a cross-sectional view of the low emission high speed combustor operating condition

FIG. 6 is a schematic view of premixed flame ports of a flame holder producing a premixed flame

FIG. 7 is a diagram of the tangential and radial air intake of the flame holder into an air flow

FIG. 8 is a schematic view of a circular flame port

FIG. 9 is a schematic view of a rectangular flame nozzle

FIG. 10 is a schematic view of a butterfly flame nozzle

FIG. 11 is a schematic view of an oblong flame nozzle

FIG. 12 is a cross-sectional view of a gas conduit and an air-fuel premixer

FIG. 13 is a cross-sectional view of a gas conduit and an air-fuel premixer of the first embodiment

FIG. 14 is a schematic view of a flameless combustion device

FIG. 15 is a line graph of NOx emissions from a low emission high speed combustor as a function of furnace temperature

FIG. 16 is a line graph showing the variation of combustion NOx emissions with furnace temperature in the two-and three-flame combustion and flameless combustion modes of the second and third embodiments

Detailed Description

The technical scheme of the utility model is described below with reference to the accompanying drawings:

embodiment one:

referring to fig. 1 to 15, the low-emission high-speed combustor 10 of the present utility model includes: the burner comprises a burner body 1, agas input device 2, an air-fuel premixing device 3, a flame stabilizer 4 and aflame tube 5, wherein central axes of the burner body 1, the air-fuel premixing device 3, the flame stabilizer 4 and theflame tube 5 are arranged in the same direction.

The burner body 1 is provided with agas duct 11, anair delivery passage 12 and anair input port 121 communicating with theair delivery passage 12, wherein thegas duct 11 is provided in theair delivery passage 12, and theair delivery passage 12 is circumferentially arranged on the outer side of thegas duct 11 in the axial direction.

Thegas input device 2 is connected to the upstream end of thegas conduit 11, and has agas input port 21 communicating with thegas conduit 11.

The air-fuel premixing device 3 is of a hollow tubular structure, is provided with an air-fuel premixing cavity 31 communicated with thegas conduit 11 and theair conveying channel 12 respectively, and is provided with a premixing gasmain nozzle 32 communicated with the air-fuel premixing cavity 31.

The flame holder 4 is sleeved at the downstream end of the air-fuel premixing device 3, and is provided with aflame holding cavity 41 communicated with the premixed gasmain nozzle 32, a plurality of primary axialair inlet ports 42 communicated with theflame holding cavity 41, a plurality of secondary axialair inlet ports 43 positioned at the outer side of the flame holder 4 and communicated with theair conveying channels 12, and a premixedflame nozzle 44 positioned at the downstream end opening of the flame holder 4 and provided with a plurality oflobe structures 441 in the circumferential direction, wherein the primary axialair inlet ports 42 are arranged at the upstream end of the flame holder 4 and are arranged in the same direction as the premixed gasmain nozzle 32, a plurality of secondaryair conveying channels 431 are circumferentially arranged at the outer side of the flame holder 4 along the length direction, the secondary axialair inlet ports 43 are arranged at the downstream ports of the secondaryair conveying channels 431, and the secondary axialair inlet ports 43 are positioned between theadjacent lobe structures 441 of thepremixed flame nozzle 44.

Theflame tube 5 is positioned at the downstream end of the burner body 1 and is communicated with theflame stabilizing cavity 41, aflame nozzle 51 with a gradually narrowing caliber communicated with theflame stabilizing cavity 41 is arranged, and the premixedflame nozzle 44 is positioned in theflame tube 5.

Thepremixed flame ports 44 having a plurality of wave-shaped structures 441 in the circumferential direction are, for example, a structure in which a plurality of semicircular or semi-elliptical holes are provided in the circumferential direction of thepremixed flame ports 44.

Compared with the prior art, the low-emission high-speed combustor 10 of the utility model ensures that the air flow conveyed by theair conveying channel 12 enters the flame holder 4 in a multi-way and is subjected to staged combustion with the air premixed flow discharged by the air premixedmixer 3 by arranging the primaryaxial air inlet 42 on the inner side of the flame holder 4 and the secondaryaxial air inlet 43 on the outer side of the flame holder 4 respectively, and forms staged combustion of theprimary combustion zone 442 and thesecondary combustion zone 443 at the premixedflame nozzle 44 of the flame holder 4, so that the full combustion reaction can better inhibit NOx generation; the provision of secondary axialair intake ports 43 between adjacent lobe-like structures 441 enhances the effective mixing of the air flow generated by the secondary axial air intake ports with the premixed flame generated by thepremixed flame ports 44, while providing a more complex swirling flow of the premixed flame between the lobe-like structure outlets and the lips of thepremixed flame ports 44, providing a reliable flame stabilizing structure for secondary combustion of the premixed flame, and providing a conical expanding flame under centrifugal force when rotated, better mixing with the air ejected from the secondary axialair intake ports 43 when exiting thepremixed flame ports 44. In addition, the premixed flame burns rapidly in theflame tube 5 with the contractedflame nozzle 51, and the gas expands due to high temperature to generate certain back pressure in theflame tube 5, and the back pressure drives the flame to jet from theflame nozzle 51 at high speed, so that the smoke recirculation combustion in the furnace is enhanced, the generation of NOx and CO is restrained, the fuel gas is well combusted, the emission of nitrogen oxides and combustion particles is reduced, and the use effect is good.

Referring to fig. 1 to 7, in one embodiment, theflame ports 51 are butterfly ports with a flat middle and increased calibers on two adjacent sides; through such setting, through adjusting the gas flow distribution offlame nozzle 51 length direction, obtain more even flat flame for the flame has better heating performance, simultaneously owing to have bigger contact surface area with the stove gas, can improve the drawing and entrainment ability of flame to and make the interior flue gas of stove dispel the heat and cool down more fast, the ability of restraining NOx formation is stronger.

The flame holder 4 provides excellent mixing effect of fuel gas and air, so that the combustion intensity and the back pressure of a combustion chamber in theflame tube 5 are greatly improved, and theflame tube 5 has the basic condition of realizing ultra-high-speed flame jet. Due to the excellent flame stabilizing performance of the flame stabilizer 4, the combustion boundary conditions of the burner are greatly expanded, so that the burner has an ultra-wide adjusting range.

In other embodiments, theflame ports 51 may be oblong, round, rectangular, oblong, rectangular, etc.

Referring to fig. 3 to 7, in one embodiment, the flame holder 4 is further provided with a plurality ofradial air inlets 45 and a plurality oftangential air inlets 46 communicated with theflame holding cavity 41, a plurality of primaryaxial air inlets 42 are arranged in the same direction as the premixed gasmain nozzle 32 and surround the central axis of the flame holder 4, the primaryaxial air inlets 42 can be arranged with a ring or multiple rings, the plurality ofradial air inlets 45 are arranged around the flame holder 4 along the radial direction, the plurality oftangential air inlets 46 are arranged around the flame holder 4 and are arranged in opposite inclination along the radial direction, the plurality oftangential air inlets 46 are arranged at intervals with the plurality ofradial air inlets 45, the plurality oftangential air inlets 46 are arranged at the downstream of the plurality ofradial air inlets 45, the circumferentially adjacenttangential air inlets 46 are arranged in a staggered manner, and the circumferentially adjacentradial air inlets 45 are arranged in a staggered manner; by means of the arrangement, the primaryaxial air inlet 42, theradial air inlet 45 and thetangential air inlet 46 are arranged in theflame stabilizing cavity 41, so that three-dimensional and crossed net-shaped jet structures are formed in the flame stabilizer 4 by air flows and air-fuel premixed air flows with three different angles, directions and diameters, and innumerable vortexes with different dimensions, momentum and directions can be formed, and therefore possible residence points of innumerable flames are generated, and flame stability, flame regulation ratio and combustion intensity of the burner are greatly improved.

Referring to fig. 3 to 7, in one embodiment, the air-fuel premixer 3 is further provided with a plurality of premixed gas radialflame stabilizing nozzles 33, the premixed gasmain nozzle 32 is disposed at the downstream end of the air-fuel premixer 3 along the axial direction, and the plurality of premixed gas radialflame stabilizing nozzles 33 are disposed at the outer side of the premixed gasmain nozzle 32 along the radial direction in a circumferential direction and are disposed in theflame stabilizing cavity 41; by this arrangement, the air-fuel premixing auxiliary air flow generated by the premixed air radialflame stabilizing nozzle 33 forms a plurality of stable ignition sources by matching with the primary air jet generated by the primary air axial input port at the upstream part of the flame stabilizer 4, thereby improving the flame stability of the burner.

Referring to fig. 3 to 7, 12 and 13, in one embodiment, the downstream end of thegas conduit 11 is provided with agas nozzle 13, thegas nozzle 13 may be a single-hole ormulti-hole gas nozzle 13, the upstream end of the air-fuel premixer 3 is provided with an axialpremix gas inlet 34 matched with thegas nozzle 13, and a radialpremix air inlet 35 circumferentially arranged outside the axialpremix gas inlet 34 and communicated with theair conveying channel 12; by this arrangement, the plurality of radialpremix air inlets 35 in the air-fuel premixer 3 premix the fuel gas inputted from the axial premixfuel gas inlets 34 from a plurality of different directions and angles, and the air-fuel gas mixing effect is good.

Referring to fig. 3 to 7, in the present embodiment, several tangentialair intake openings 46 are arranged at the same oblique angle in the radial direction; by means of the arrangement, the air jet flow input by the radialair inlet opening 45 is used for smashing the air-fuel premixed jet flow input by the premixed airmain nozzle 32, mixing is promoted, the air-fuel premixed jet flow input by the premixed airmain nozzle 32 is slowed down by matching with air flow cutting input by the tangentialair inlet opening 46, meanwhile, the air-fuel premixed jet flow is pushed to rotate, the swirl flame is subjected to centrifugal force at the outlet of the flame holder 4 to form conical expansion flame, and better conditions are created for mixing combustion with the air flow input by the secondary axialair inlet opening 43.

In an alternative embodiment (not shown), several tangentialair inlet openings 46 are arranged at different oblique angles in the radial direction; through the arrangement, the air jet flow which is convenient to generate forms a plurality of flame stabilizing ignition points which are not at the same plane height with the gas jet flow which is generated by the gas jet, so that the flame stabilizing burner has larger gas regulation ratio, and can fully burn the gas when the gas flow of the gas jet is smaller, thereby having good use effect.

Referring to fig. 1, in one embodiment, further comprising aflame ion probe 47 and anigniter 48 disposed within the flame holder 4; theflame rectifying tube 49 is sleeved outside the downstream end of the flame holder 4, and theflame tube 5 is sleeved outside theflame rectifying tube 49 and the downstream end of the burner body 1.

Referring to fig. 3 to 7, in operation, the low emission high speed burner 10 of the present utility model is operated by introducing air into the air passage from the air input port 121 and introducing fuel gas into the fuel gas input port 21, respectively; the fuel gas enters the air-fuel premixing cavity 31 of the air-fuel premixing device 3 from the fuel gas conduit 11 through the fuel gas nozzle 13 and the axial premixing fuel gas inlet 34 in the axial direction, and the air enters the air-fuel premixing cavity 31 of the air-fuel premixing device 3 from the radial premixing air inlet 35 in different radial angles respectively and is fully mixed with the fuel gas to form air-fuel premixing airflow; the air-fuel premixed gas flows respectively enter the flame stabilizing cavity 41 from the premixed gas main nozzle 32 in the axial direction and the premixed gas radial flame stabilizing nozzle 33 in the radial directions, and in addition, part of air in the air channel respectively enters the flame stabilizing cavity 41 from the primary axial air inlet 42, the radial air inlet 45 and the tangential air inlet 46 in different angles to be further mixed with the air-fuel premixed gas flows and is combusted under the action of the igniter 48 to generate flame; the air jet flow input by the radial air inlet 45 breaks up and slows down the air-fuel premixed jet flow input by the premixed air main nozzle 32, promotes mixing, simultaneously pushes the air-fuel premixed jet flow to rotate when being matched with the air flow cutting input by the tangential air inlet 46 to slow down the air-fuel premixed jet flow input by the premixed air main nozzle 32, the swirl flame forms conical expansion flame under the action of centrifugal force on the outlet of the flame holder 4 and the action of the lobe structure outlet, the formed conical expansion flame is further mixed and combusted with air sprayed by the secondary axial air inlet 43 in the flame tube 5 after being discharged by the premixed flame nozzle 44, and finally the flame is sprayed from the flame nozzle 51 at a high speed through back pressure in the flame tube 5.

Embodiment two:

referring to fig. 1 to 16, a main object of the present embodiment is to provide a flameless combustion device of the low-emission high-speed combustor 10 according to the first embodiment, which includes aflameless combustor 6 and the low-emission high-speed combustor 10, wherein theflameless combustor 6 includes a flameless gas combustion tube 61, a flameless gas inlet (not shown) provided at an input end of the flameless gas combustion tube 61, and a flamelessgas combustion nozzle 63 provided at an output end of the flameless gas combustion tube 61. With this arrangement, since a certain critical furnace temperature condition (typically 750 ℃) is required to operate the flameless combustion mode, it is not possible to operate below the critical furnace temperature condition, and other combustion modes must be used. The low-emission high-speed burner 10 of the present utility model has excellent low-nitrogen performance in a low-temperature state, so that the low-nitrogen target can be achieved in the whole process from low-temperature start-up to high-temperature operation by combining it with theflameless burner 6.

Referring to fig. 1 to 16, in a further embodiment, the burner block 7 is further comprised, theflameless burner 6 and the low-emission high-speed burner 10 are mounted and fixed on the burner block 7, theflameless burner 6 is provided with at least two, and is arranged circumferentially outside the low-emission high-speed burner 10, and the side of the flameless gas combustion tube 61 near the flamelessgas combustion nozzle 63 is arranged obliquely along the side of theflame ports 51 of the low-emission high-speed burner 10. By this arrangement, when the furnace rises above the critical furnace temperature condition, the gas supply to the low-emission high-speed burner 10 is turned off, and theliner 5 is used only as air transportation. When the gas supply of theflameless burner 6 is turned on, the gas injection speed is not lower than 80m/s, theflameless burner 6 and the low-emission high-speed burner 10 are arranged at an opposite included angle, so that gas jet and air jet generated by theflameless burner 6 and the low-emission high-speed burner are mutually attracted and fused at a preset position, and simultaneously, the high-speed gas jet has ERG effect on the strong entrainment capacity of inert smoke, so that the high-temperature smoke is promoted to be recycled internally or externally, and the generation of NOx is further effectively inhibited.

Embodiment III:

referring to fig. 1 to 16, a main object of the present embodiment is to provide a method for igniting a flameless combustion device to which the flameless combustion device of the second embodiment is applied, involving the flameless combustion device provided in a furnace, the method comprising the steps of:

a. the low-emission high-speed burner 10 is respectively fed with fuel gas and air, and theflameless burner 6 is fed with fuel gas, and theigniter 48 of the low-emission high-speed burner 10 ignites the mixed gas consisting of the fuel gas and air in the flame holder 4 to generate flame through theflame nozzle 51.

b. When the temperature in the furnace reaches [720,780 ]. DEG C, the gas input to the low-emission high-speed combustor 10 is turned off, thereby starting the flameless combustion mode of the flameless combustion device.

With this arrangement, since a certain critical furnace temperature condition (typically 750 ℃) is required to operate the flameless combustion mode, it is not possible to operate below the critical furnace temperature condition, and other combustion modes must be used. The low-emission high-speed burner 10 of the present utility model has excellent low-nitrogen performance in a low-temperature state, so that the low-nitrogen target can be achieved in the whole process from low-temperature start-up to high-temperature operation by combining it with theflameless burner 6.

Variations and modifications to the above would be obvious to persons skilled in the art to which the utility model pertains from the foregoing description and teachings. Therefore, the utility model is not limited to the specific embodiments disclosed and described above, but some modifications and changes of the utility model should be also included in the scope of the claims of the utility model. In addition, although specific terms are used in the present specification, these terms are for convenience of description only and do not limit the present utility model in any way.

Claims (9)

1. A low emission high speed burner comprising:

the burner comprises a burner body, a gas guide pipe, an air conveying channel and an air input port, wherein the gas guide pipe, the air conveying channel and the air input port are arranged in the burner body;

the fuel gas input device is connected to the upstream end of the fuel gas conduit and is provided with a fuel gas input port communicated with the fuel gas conduit;

the air-fuel premixing device is provided with an air-fuel premixing cavity communicated with the gas guide pipe and the air conveying channel respectively and a premixing gas main nozzle communicated with the air-fuel premixing cavity;

the flame stabilizer is provided with a flame stabilizing cavity communicated with the premixed gas main nozzle, a plurality of primary axial air inlet ports communicated with the flame stabilizing cavity, a plurality of secondary axial air inlet ports positioned at the outer side of the flame stabilizer and communicated with the air conveying channel, and a premixed flame nozzle which is positioned at the downstream end of the flame stabilizer and circumferentially provided with a plurality of wave-shaped structures, wherein the secondary axial air inlet ports are positioned between adjacent lobe-shaped structures;

the flame tube is positioned at the downstream end of the burner body and is provided with a flame nozzle with a gradually narrowed caliber communicated with the flame stabilizing cavity.

2. The low emission high-speed burner of claim 1, wherein the flame ports are butterfly ports having a flat middle portion and increasing calibers on adjacent sides.

3. The low emission high velocity burner according to claim 1, wherein the flame holder is further provided with a plurality of radial air inlet openings and a plurality of tangential air inlet openings communicating with the flame holding chamber, the plurality of primary axial air inlet openings being arranged co-directionally with the premix gas main nozzle and surrounding the central axis of the flame holder, the plurality of radial air inlet openings being arranged circumferentially outside the flame holder in a radial direction, the plurality of tangential air inlet openings being arranged circumferentially outside the flame holder and being arranged relatively obliquely in a radial direction.

4. The low-emission high-speed combustor according to claim 1, wherein the air-fuel premixer is further provided with a plurality of premixed gas radial flame stabilizing nozzles, the premixed gas main nozzle is arranged at the downstream end of the air-fuel premixer along the axial direction, and the plurality of premixed gas radial flame stabilizing nozzles are annularly arranged at the outer side of the premixed gas main nozzle along the radial direction and are arranged in the flame stabilizing cavity.

5. The low-emission high-speed combustor according to claim 1, wherein the gas conduit is provided with a gas nozzle at a downstream end thereof, an axial premix gas inlet matched with the gas nozzle is provided at an upstream end thereof, and a radial premix air inlet communicated with the air conveying passage is circumferentially provided outside the axial premix gas inlet.

6. A low emission high speed burner as claimed in claim 3, wherein the tangential air inlet openings are arranged at the same inclination angle in the radial direction

Alternatively, several tangential air inlet openings are arranged at different oblique angles in the radial direction.

7. The low emission high-speed combustor according to any one of claims 1 to 6, further comprising a flame ion probe and igniter disposed within the flame holder;

the flame stabilizer is characterized in that a flame rectifying tube is sleeved on the outer side of the downstream end of the flame stabilizer, and the flame tube is sleeved on the outer sides of the flame rectifying tube and the downstream end of the burner body.

8. A flameless combustion device, characterized by comprising a flameless burner and the low-emission high-speed burner according to any one of claims 1 to 7, wherein the flameless burner comprises a flameless gas combustion tube, a flameless gas inlet provided at an input end of the flameless gas combustion tube and a flameless gas combustion nozzle provided at an output end of the flameless gas combustion tube.

9. The flameless combustion device according to claim 8, wherein the flameless combustors are provided in at least two and are disposed circumferentially outside the low-emission high-speed combustor, and a side of the flameless gas combustion tube adjacent to the flameless gas combustion nozzle is disposed obliquely along a flame port side of the low-emission high-speed combustor.

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