CN112204307B - Low NOx burner with punched plate type burner head - Google Patents
Low NOx burner with punched plate type burner head Download PDFInfo
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- CN112204307B CN112204307B CN201980000915.3A CN201980000915A CN112204307B CN 112204307 B CN112204307 B CN 112204307B CN 201980000915 A CN201980000915 A CN 201980000915A CN 112204307 B CN112204307 B CN 112204307B
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- stage
- pipe
- combustion chamber
- fuel
- plate type
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Classifications
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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
- F23C9/00—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
- F23C9/06—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for completing combustion
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/02—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/20—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone
- F23D14/22—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone with separate air and gas feed ducts, e.g. with ducts running parallel or crossing each other
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details, e.g. noise reduction means
- F23D14/48—Nozzles
- F23D14/58—Nozzles characterised by the shape or arrangement of the outlet or outlets from the nozzle, e.g. of annular configuration
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details, e.g. noise reduction means
- F23D14/70—Baffles or like flow-disturbing devices
Abstract
The present invention relates to a low nox burner equipped with a perforated plate type burner, wherein a 1 st stage pipe is installed so as to protrude into the inside of a combustion chamber, a 1 st stage fuel supply pipe is disposed inside the 1 st stage pipe, the perforated plate type burner is disposed at the tip of the 1 st stage fuel supply pipe so as to be spaced apart from the tip of the 1 st stage pipe, a plurality of 2 nd stage fuel injection bodies are disposed so as to surround the 2 nd stage pipe, and a distance adjusting means is provided to adjust the distance between the perforated plate type burner and the tip of the 1 st stage pipe by moving the perforated plate type burner in the axial direction. The present invention can be applied to a smoke tube boiler equipped with a combustion chamber structure in which reduction of nitrogen oxides is difficult to achieve because the volume of the combustion chamber is relatively small and the reduction of flame temperature is relatively slow, and can reduce the generation of nitrogen oxides more effectively.
Description
Technical Field
The present invention relates to a low nitrogen oxide burner (Low NOx Burner Having Combustion Head of Perforated Plate Type) equipped with a punched plate type burner, and more particularly, to a low nitrogen oxide burner which can easily repair, replace and adjust the burner, and can more effectively reduce the generation of nitrogen oxides (NOx) (hereinafter, simply referred to as "nitrogen oxides"), and which is equipped with a punched plate type diffuser suitable for use as a burner of a flue tube type boiler.
Background
Nitrogen oxides are compounds of nitrogen and oxygen, such as nitric oxide and nitrogen dioxide, that are generated when fossil fuels are combusted.
Nitrogen oxides can be classified into fuel-type nitrogen oxides (fuel Nox), thermal-type nitrogen oxides (transient Nox) according to their formation mechanism. The fuel-type nitrogen oxides are generated because nitrogen contained in the fuel is oxidized during combustion. The thermal nitrogen oxides are produced by the oxidation of nitrogen contained in the combustion air after the dissociation thereof at a high temperature of 1300 ℃ or higher during the combustion. The transient nitrogen oxides are generated by exposing the fuel in a high concentration state to a high temperature of 1000 ℃ or higher before mixing with the combustion air.
The nitrogen oxides as described above, together with the hydrocarbon, become causes of generation of photochemical smog occurring under the influence of sunlight. Furthermore, nitrogen oxides smell even in the presence of only 1 to 3ppm, and not only cause a decrease in immunity against respiratory diseases, but also form methemoglobin (methemoglobin) by reacting with hemoglobin in blood and thus hinder the transfer of oxygen. In addition, nitrogen dioxide is a reddish brown irritant gas that is more toxic than nitric oxide, resulting in acute pulmonary edema, obstructive tracheitis, pneumonia, and the like. Accordingly, research and development of related technologies capable of reducing nitrogen oxides have been continuously pursued.
Low-nox burners have been studied and developed in the direction of reducing the concentration of nitrogen oxide emissions by reducing the formation of nitrogen oxides by modifying the burner configuration in which fuel and oxygen are combined so that the formation of nitrogen oxides can be suppressed.
In addition, boilers applicable to the burner are classified into a water pipe type boiler and a smoke pipe type boiler.
The water tube type boiler is a boiler for generating high pressure steam by heating water circulating through a steam boiler drum and a water boiler drum, has the characteristics of a wide area of a combustion chamber, a short length and a flame which is required to be large and short according to the characteristics of the combustion chamber, can realize more heat transfer by means of a structure with a large volume of the combustion chamber, and is a combustion chamber structure which is favorable for reducing nitrogen oxides.
As shown in fig. 1, a water tube type burner 1 suitable for a water tube type boiler includes: the stage 1 fuel injection body 10 is disposed in the center of an opening formed in front of the combustion chamber FR; a stage 2 fuel injection body 20 which is disposed around the stage 1 fuel injection body and is closely adhered to the inner side of the opening; a swirler 30 disposed at the front end of the stage 1 fuel injection body 10; a stage 1 pipe 40 disposed so as to surround the stage 1 fuel injection body 10 and the swirler 30; the recirculation inducing portion 50 is of a double pipe type, and includes a stage 2 pipe 51 and a recirculation pipe 52 disposed between the stage 1 pipe 40 and the stage 2 fuel injection body 20.
The water tube burner 1 as described above can maximize the distance between the outer flames by enlarging the arrangement diameter D of the 2 nd stage fuel injection body 20 in the water tube boiler having a wide combustion chamber, can form a flame having a short distance and wide spread by the cyclone 30 from the center flame injected and generated by the 1 st stage fuel injection body 10, and can form a partially premixed (partial premix) flame by reversely injecting a part of the 1 st stage fuel gas and swirling it with air before reaching the cyclone 30, thereby reducing the generation amount of nitrogen oxides.
However, the partially premixed flame as described above has a problem in that combustion instability increases when operating in a state where the amount of fuel gas on the 1 st stage side is about 20% or less of the total amount of fuel gas, because the length of the flame is short.
Prior art literature
Patent literature
Chinese patent publication CN107690557A (date of publication: 2018.02.13.)
Patent content
The invention aims to provide a low nitrogen oxide burner with a punched plate type burner, which can be easily maintained, replaced and adjusted by changing the structure to be suitable for the burner of a smoke tube type boiler and applying the punched plate type burner.
Another object of the present invention is to provide a low nox burner equipped with a punched plate type burner that can be applied to a smoke tube type boiler equipped with a combustion chamber structure in which reduction of nox is difficult to achieve because the volume of the combustion chamber is relatively small and the reduction of flame temperature is relatively slow and can reduce the generation of nox more effectively.
It is still another object of the present invention to provide a low nox burner equipped with a perforated plate type burner head capable of ensuring combustion stability of the burner even when the gas fuel amount on the 1 st stage side is about 10% or less of the total gas amount by means of a stable center flame.
It is still another object of the present invention to provide a low nox burner equipped with a perforated plate type burner capable of reducing nitrogen oxides by reducing the arrangement diameter of the 2 nd stage fuel injection body and increasing the inflow amount of the recirculated fuel gas.
In order to achieve the object of the present invention, a low nox burner equipped with a punch plate type burner according to the present invention comprises: a stage 1 pipe installed to protrude toward the inside of the combustion chamber for guiding air to the inside of the combustion chamber; a stage 1 fuel supply pipe disposed inside the stage 1 pipe for realizing stage 1 fuel supply; a perforated plate type burner head disposed at a front end of the 1 st stage fuel supply pipe at a predetermined interval from a distal end of the 1 st stage pipe, for radially injecting fuel supplied through the 1 st stage fuel supply pipe while diffusing air guided by the 1 st stage pipe; a stage 2 pipe disposed in such a manner as to surround the stage 1 pipe for inducing unburned gas of the combustion chamber between the stage 1 pipes and thereby guiding injection into the interior of the combustion chamber; a plurality of stage 2 fuel injection bodies arranged around the stage 2 pipe for injecting the stage 2 fuel; and a distance adjusting means for moving the punched plate type combustion head in the axial direction and thereby adjusting the distance of separation from the end of the stage 1 pipe.
A distance adjustment appliance, comprising: the flange is fixed on the outer side surface of the 1 st-stage fuel supply pipe; a connecting rod connected to the flange; and an adjusting rod coupled to the connecting rod for adjusting the position of the stage 1 fuel supply pipe by moving the same.
The stage 1 pipe is connected to an inside of an air induction pipe fixed to a wall of the combustion chamber and used for guiding air induction to the inside of the stage 1 pipe and the outside.
An inclined part inclined to the outer side surface of the 1 st stage pipe is formed in front of the air guiding pipe, and a combustion gas circulation interval for circulating combustion gas of the combustion chamber and re-supplying the combustion gas into the combustion chamber is formed between the inclined part and the 2 nd stage pipe.
A plurality of 1 st support ribs for providing support in the case of aligning centers are provided between the 1 st stage pipe and the 2 nd stage pipe, and a plurality of 2 nd support ribs protruding toward the 2 nd stage pipe side and supporting the outer side surface of the 2 nd stage pipe are provided in the air induction pipe inclined portion.
An axial diameter portion having a cross section inclined at a specific angle to the punched plate type burner head is formed at the front end portion of the stage 1 pipe.
An expansion pipe portion for diffusing air at the combustion chamber side end of the cylindrical portion to the outside of the combustion chamber is formed in the stage 2 pipe, and a support portion for supporting the stage 2 fuel injection body is provided on the outer peripheral surface of the expansion pipe portion.
The end of the nozzle pipe for injecting the stage 2 fuel in the stage 2 fuel injection body is provided with a fork pipe into which combustion gas of the combustion chamber flows and which redirects the injection into the combustion chamber.
An inclined surface for injecting the mixture of the 2 nd-stage fuel and the combustion gas obliquely to the outside of the combustion chamber is formed at the end of the fork pipe. The center length of the fork tube is more than 10 times of the inner diameter.
By applying the low nox burner equipped with the punched plate type burner of the present invention as described above, the burner can be more easily repaired, replaced and adjusted, and can be applied to a smoke tube type boiler equipped with a burner structure in which it is difficult to achieve reduction of nox because the volume of the burner is relatively small and the reduction of flame temperature is relatively slow, and the generation of nox can be more effectively reduced.
Further, the combustion stability of the burner can be ensured even when the gas fuel amount on the 1 st stage side is about 10% or less of the entire gas amount by means of the stable center flame, and the nitrogen oxides can be reduced by reducing the arrangement diameter of the 2 nd stage fuel injection body and increasing the inflow amount of the recirculated fuel gas.
Drawings
Fig. 1 is a schematic view illustrating a water tube burner applied to a conventional water tube boiler.
Fig. 2 is a schematic view of a low nox burner equipped with a punch plate type burner head to which an embodiment of the present invention is applied.
Fig. 3 is a front view as seen from the front side (combustion head side) of fig. 2.
Fig. 4 is an end detail view of the burner of fig. 2.
Fig. 5 is a view showing the operation of a low nox burner equipped with a punch plate type burner head to which an embodiment of the present invention is applied.
Fig. 6 is a schematic view of a comparative burner to which the low nox burner equipped with the punched plate type burner head according to the present invention is applied.
Fig. 7 is a graph showing the results of testing the nitrogen oxide generation amounts of the low nitrogen oxide burner of fig. 2 to which the embodiment of the present invention is applied and the comparative burner of fig. 6.
[ symbolic description ]
100: low nitrogen oxide burner
110: 1 st stage tube
111: shaft diameter part
112: spacing maintaining rib
113: connecting rib
120: level 1 fuel supply pipe
121: stage 1 auxiliary fuel nozzle
130: punching plate type combustion head
131: punching plate
132: fuel injection pipe
140: 2 nd stage pipe
141: cylindrical portion
142: pipe expanding part
143: support part
144: 1 st support rib
150: 2 nd stage fuel injection body
151: level 2 fuel supply pipe
152: nozzle tube
153: fork tube
160: distance adjusting device
161: flange
162: connecting rod
163: adjusting rod
170: air induction pipe
171: cylindrical tube portion
172: inclined part
173: 2 nd support rib
180: air supply cavity
FR: combustion chamber
FC: interval of combustion gas circulation
Detailed Description
Next, preferred embodiments to which the present invention is applied will be described in detail with reference to the accompanying drawings, but this is only provided for the purpose of easily implementing the present invention by those having ordinary skill in the art to which the present invention pertains, and does not represent the technical idea and scope of the present invention and is thus limited.
Next, a low nox burner to which one embodiment of the present invention is applied will be described in detail with reference to the accompanying drawings.
Fig. 2 is a configuration diagram illustrating a low nox burner equipped with a punch plate type burner head to which an embodiment of the present invention is applied, fig. 3 is a front view seen from the front side (burner head side) of fig. 2, and fig. 4 is an end portion detail view of the burner in fig. 2.
As shown in fig. 2 to 4, the low nox burner 100 equipped with the punched plate type burner head to which the embodiment of the present invention is applied includes a stage 1 pipe 110, a stage 1 fuel supply pipe 120, a punched plate type burner head 130, a stage 2 pipe 140, a stage 2 fuel injection body 150, and a distance adjusting tool 160.
The stage 1 pipe 110 is installed to protrude toward the inside of the combustion chamber FR for guiding air to the inside of the combustion chamber FR. A shaft diameter portion 111 having a cross section inclined at a specific angle to the punched plate type burner head 130 is formed at the front end portion of the stage 1 pipe 110. The inclined shaft diameter portion 111 suppresses the phenomenon that the width of the center flame is widened by focusing air at the center of the burner, and at the same time, increases the air supply speed by reducing the air passing area of the air supply passage of the air supplied to the inside of the combustion chamber FR.
A plurality of (3 in this embodiment) interval maintaining ribs 112 are formed at regular intervals along the inner circumferential surface of the stage 1 pipe 110 at the end inner circumferential surface of the stage 1 pipe 110, and the interval maintaining ribs 112 maintain the interval C between the perforated plate of the perforated plate type burner head 130 and the shaft diameter portion 111 of the stage 1 pipe 110 while guiding the movement of the perforated plate type burner head 130. A blocking ridge 112a is formed at the outer end of the interval maintaining rib 112 so as to limit the protruding distance of the punched plate type burner 130. The opposite side of the barrier rib 112a of the interval maintaining rib 112 is bent in the radial direction of the stage 1 pipe 110 and fixed to the inner circumferential surface of the stage 1 pipe 110. The intermediate portion of the interval maintaining rib 112 will slidingly guide a later-described perforated plate of the perforated plate type burner 130 when it moves.
Further, the stage 1 pipe 110 is connected to the inside of an air induction pipe 170 communicating with an air supply chamber to be described later in the circumferential direction by a plurality of connection ribs 113.
The stage 1 fuel supply pipe 120 is a pipe disposed inside the stage 1 pipe 110 for achieving the stage 1 fuel supply, and an end thereof is combined with the perforated plate type burner head 130. The end of the stage 1 fuel supply pipe 120 is in a closed state, and the end thereof is connected to a fuel injection pipe of a later-described perforated plate type burner 130, so that the stage 1 fuel is injected in a radial shape.
A central air injection pipe that independently injects air with a flame as a central portion can be provided inside the stage 1 fuel supply pipe 120. When the diameter of the stage 1 pipe 110 is large, the flame center portion is brought into a high temperature state due to the large diameter of the generated flame, and the central air injection pipe is used to solve the above-described problem (appropriately reduce the temperature) and the tip portion thereof is opened to the combustion chamber FR so that air can be independently supplied to the flame center portion.
The perforated plate type burner 130 is disposed at the front end of the stage 1 fuel supply pipe 120 with a certain interval C from the end of the stage 1 pipe 110, and radially injects fuel, which is supplied in the stage 1 through the stage 1 fuel supply pipe 120 while diffusing air guided by the stage 1 pipe 110, including a perforated plate 131, a plurality of fuel injection pipes 132, and an igniter 133.
The perforated plate 131 is provided so that the end of the stage 1 fuel supply pipe 120 is installed through the center, and a plurality of air injection holes 131a are formed between the respective fuel injection pipes 132 in an aligned manner. The air supplied to the inside of the combustion chamber through the air injection holes 131a forms a plurality of high-speed airflows, and a vortex is formed at the periphery thereof by the plurality of high-speed airflows as described above, and uniform mixing of fuel and air can be achieved by the vortex as described above.
The plurality of fuel injection pipes 132 are radially connected to the outer circumferential surface of the stage 1 fuel supply pipe 120 on the outside (combustion chamber side) of the perforated plate 130, and stage 1 main fuel nozzles 132a are individually formed at the ends thereof. The respective fuel injection pipes 132 can be disposed at mutually different positions along the axial direction of the 1 st stage fuel supply pipe 120, and therefore, the injection positions of the respective 1 st stage main fuel nozzles 132a provided in the fuel injection pipes 132 will also be mutually different, thereby achieving uniform fuel injection in a wider area, and thereby further preventing the phenomenon of an increase in fuel concentration in a specific area.
Further, a plurality of stage 1 auxiliary fuel nozzles 121 are radially formed in the outer peripheral surface of the front end of the stage 1 fuel supply pipe 120 adjacent to the fuel injection pipe 132. The respective 1 st-stage auxiliary fuel nozzles 121 are identical to the respective 1 st-stage main fuel nozzles, and can achieve uniform fuel injection by being disposed at mutually different positions of the front end of the 1 st-stage fuel supply pipe 120.
An igniter 133 is attached to the outer peripheral surface of the end portion of the stage 1 fuel supply pipe 120 via a support base, and a spark plug is disposed so as to penetrate the perforated plate 131.
The stage 1 pipe 140 is disposed in such a manner as to surround the stage 1 pipe 110 for inducing unburned gas of the combustion chamber FR between the stage 1 pipes 110 and thereby guiding injection into the interior of the combustion chamber FR. A stage 2 pipe 140 comprising: a cylindrical portion 141; an expansion pipe portion 142 for diffusing air at the combustion chamber side end portion of the cylindrical portion 141 to the outside of the combustion chamber FR; and a support portion 143 for supporting the stage 2 fuel injection body 150 outside the expanded pipe portion 142 at Zhou Miandui. Further, a plurality of 1 st support ribs 144 for supporting the tube with ease of centering the tube are provided between the 1 st stage tube 110 and the cylindrical portion 141 of the 2 nd stage tube 140, and a plurality of 2 nd support ribs described later are provided on the outer peripheral surface of the 2 nd stage tube 140.
The stage 2 fuel injection body 150 is disposed in plurality so as to surround the stage 2 pipe 140 and the air induction pipe 170, thereby achieving the stage 2 fuel injection. A stage 2 fuel injector 150, comprising: a nozzle pipe 152 connected to an end of a 2 nd stage fuel supply pipe 151 penetrating the combustion chamber wall and supplying 2 nd stage fuel; and a fork tube 153 for injecting the fuel from the end of the nozzle tube 152 to induce the injection of the 2 nd stage fuel mixed with the combustion gas after the inflow of the unburned gas of the combustion chamber into the combustion chamber FR.
An inclined surface 153a for injecting the mixture of the stage 2 fuel and the combustion gas obliquely to the outside of the combustion chamber FR is formed at the end of the fork tube 153. By providing the inclined surface 153a inclined to the outside of the combustion chamber FR, the fuel of stage 2 is prevented from being injected toward the center and burned together with unburned gas at a low temperature in the periphery, thereby reducing the amount of nitrogen oxides generated.
The center length L of the fork tube 153 is 10 times or more the inner diameter d 1. When the length of the fork tube 153 is short, a stable flow path cannot be ensured due to insufficient dilution of the fuel and the combustion gas, and combustion efficiency is reduced.
The distance adjusting means 160 for moving the punched plate type burner 130 in the axial direction and thereby adjusting the interval distance from the end of the stage 1 pipe 110 includes: a flange 161 fixed to an outer side surface of the stage 1 fuel supply pipe 120; a connecting rod 162 connected to the flange 161; and an adjustment rod 163 coupled to the connection rod 162 for adjusting the position (moving distance) of the stage 1 fuel supply pipe 120 by moving it. The adjustment bar 163 is adjusted outside the burner by a handle or an adjustment mechanism.
The air induction pipe 170 guides air induction to the inside and outside of the stage 1 pipe 110 by fixing the cylindrical pipe portion 171 to the wall of the combustion chamber, and is protruded to be installed to the inside of the air supply chamber 180 installed at the front outside of the combustion chamber FR.
An inclined portion 172 inclined toward the outer side surface of the 1 st stage pipe 110 is formed in front of the cylindrical pipe portion 171 of the air induction pipe 170, and a combustion gas circulation interval RC through which combustion gas of the combustion chamber FR circulates and is resupplied to the inside of the combustion chamber FR is formed between the inclined portion 172 and the 2 nd stage pipe 140. Further, a plurality of 2 nd support ribs 173 protruding toward the 2 nd pipe 14 side and supporting the outer side surface of the 2 nd pipe 140 are provided in the circumferential direction in the inclined portion 172. At this time, the 2 nd support rib 173 can support the outer side surface of the 2 nd stage pipe 140 longer in the length direction, thereby improving stability thereof and making center alignment of the 2 nd stage pipe 140 easier.
As shown in fig. 5, the low nox burner equipped with the punched plate type burner of the embodiment of the present invention constructed as described above, the 1 st stage fuel will be supplied to the center of the combustion chamber through the 1 st stage fuel supply pipe 120 in the direction of arrow a, while the 2 nd stage fuel will be supplied to the center periphery of the combustion chamber through the plurality of 2 nd stage fuel supply pipes 151 of the 2 nd stage fuel injection body 150 in the direction of arrow B, air will be supplied to the combustion chamber through the air induction pipe 170 via the inside and outside of the 1 st stage pipe 110 in the direction of arrow E, and the mixture of fuel and air will burn and form a center flame (1 st stage flame) and a peripheral flame (2 nd stage flame).
The stage 1 fuel supplied through the stage 1 fuel supply pipe 120 is injected in the punched plate type combustion head 130 in a radial shape through the fuel injection pipe 132 in the stage 1 main fuel nozzle 132a and is injected into the combustion chamber after being mixed with air injected through the tip of the stage 1 pipe 110 and the interval C between the punched plates 131, while the combustion occurs through the stage 1 auxiliary fuel nozzle 121 and is injected into the combustion chamber after being mixed with air. At this time, the fuel injected through the stage 1 main fuel nozzle 132a and the air supplied through the interval C between the tip of the stage 1 pipe 110 and the outer circumferential surface of the perforated plate 131 will intersect at right angles to each other, whereby the supplied air and the fuel telled to be injected through the plurality of nozzles will intersect and mix at right angles to each other, thereby achieving a very rapid mixing action of the air and the fuel.
The fuel and air can be uniformly mixed by the extremely rapid mixing as described above, so that the phenomenon that the fuel burned in the combustion chamber FR is partially air-deficient is avoided. The condition of complete combustion is that the supply of air required for combustion is received from the periphery in time at the time of fuel combustion, and the extremely rapid mixing can satisfy the condition required for complete combustion to a considerable extent by enabling proper mixing of air and fuel. At this time, by properly mixing air with fuel by means of the extremely rapid mixing, not only the occurrence of incomplete combustion at the time of fuel combustion can be minimized, but also the generation of transient nitrogen oxides can be minimized. This means that the fuel can achieve a combustion state close to complete combustion, at which time the generation of carbon monoxide (CO) can be minimized because the fuel exhibits combustion characteristics close to complete combustion.
In addition, although the opposed jet system in which air and fuel are injected and mixed in the opposed direction at an angle of 180 degrees contributes to the maximization of the mixing effect, the opposed jet system as described above may cause air to obstruct the flow of fuel when applied to most of the burners in which the amount of combustion needs to be adjusted, and therefore should be designed to be maximally close to the opposed jet system in a range in which the flow angle of air does not hinder the injection of fuel. Therefore, the traveling direction of the air supplied along the interval C in the present invention should employ an angle corresponding to the inclination angle of the shaft diameter portion 111 of the stage 1 pipe 110, whereby the crossing angle of the air and the fuel can form an obtuse angle slightly greater than 90 degrees so as to be closer to the opposed jets.
As described above, in the embodiment to which the present invention is applied, it is possible to achieve the extremely rapid mixing of air and fuel by maximizing the supply speed of air by means of the shaft diameter portion 111 of the stage 1 pipe 110 and making the injection direction of fuel injected at high speed by the stage 1 main fuel nozzle 132a nearly at right angles to the supply direction of air, whereas by the extremely rapid mixing as described above, not only the generation of transient nitrogen oxides (prompt NOx) can be prevented, but also more compact flames can be further achieved.
Further, by injecting the stage 2 fuel supplied via the stage 2 fuel supply pipe 151 through the fork pipe 153 at the end of the nozzle pipe 152, the unburned gas of the combustion chamber FR will flow into the interior of the fork pipe 153 in the direction of arrow F and be injected into the combustion chamber after the unburned gas is mixed. At this time, since the inclined surface 153a inclined to the outside of the combustion chamber FR is provided at the end portion of the fork tube 153, the 2 nd stage fuel can be prevented from being injected toward the center and burned together with the unburned gas under the surrounding low temperature condition, and the amount of nitrogen oxide generated can be reduced.
Further, a part of the air (in the arrow E direction) flowing into the inside of the air inducing tube 170 through the air supply chamber 180 will be injected into the inside of the combustion chamber FR through the air injection holes 131a of the perforated plate 131 after passing through the space (in the arrow E1 direction) between the stage 1 fuel supply tube 120 and the stage 1 tube 110, while being injected into the inside of the combustion chamber FR through the space C between the tip of the stage 1 tube 110 and the perforated plate 131.
Further, of the air (in the arrow E direction) flowing into the inside of the air inducing duct 170, the air (in the arrow E2 direction) guided by the inclined portion 172 of the air inducing duct 170 will be mixed with the unburned gas recirculated through the combustion gas circulation interval RC in the arrow G direction and injected to the combustion chamber in the process of passing through the interval between the 1 st stage duct 110 and the 2 nd stage duct 140. At this time, since the 2 nd stage pipe 140 adopts a "single pipe type" different from the conventional double pipe type, it is possible to make the unburned gas more easily flow into the inside and shorten the interval with the 2 nd stage fuel injection body 150 (reduce the disposition diameter of the 2 nd stage fuel injection body), thereby improving its manufacturing and workability. Further, since the 2 nd stage pipe 140 is in a horizontal state (in a bent state in the conventional manner) in the combustion gas circulation interval RC, it is possible to make the inflow of unburned gas easier and to increase the inflow amount (circulation amount) thereof, thereby improving the combustion efficiency of the unburned gas.
The recirculation of unburned gas in the directions of arrow F and arrow G is not only for supplying air to the fuel, but also for enabling mixing of swirling air with the fuel by forming a vortex, thereby achieving uniform mixing of the fuel and the air. In a state where the fuel particles and the air particles are uniformly mixed, the air particles around the combustion time of each fuel particle can effectively assist the combustion of the fuel particles, thereby minimizing incomplete combustion, which means that the generation of by-products (e.g., carbon monoxide) due to incomplete combustion is reduced.
Table 1 shows the amounts of nitrogen oxides (NOx) and carbon monoxide (CO) produced in different amounts of fuel (LNG) and air (O2) supplied in burners equipped with burner heads (cyclone type and perforated plate type) applied to a flue type boiler.
[ Table 1 ]
As shown in table 1, it was found that a burner equipped with a perforated plate type burner head was a low nitrogen oxide burner in which the amount of nitrogen oxides (NOx) was significantly reduced although the amount of carbon monoxide (CO) was increased in a state where the amount of the stage 1 fuel was reduced relative to the stage 2 fuel (the amount of the stage 1 fuel was 10% or less of the total fuel amount) as compared with a burner equipped with a swirler type burner head.
Fig. 7 is a graph showing the results of testing the nitrogen oxide generation amounts of the low nitrogen oxide burner 100 of fig. 2 to which the embodiment of the present invention is applied and the comparative example burner c100 of fig. 6, specifically, examples in which burners of different structures are compared. The difference between the comparative example burner c100 in fig. 6 and the embodiment to which the present invention is applied in fig. 2 is that an expanded pipe portion c121 is formed at the end and injection ports c122 for forming the premixing area are formed in the space between the interiors of the stage 1 pipes c110, the end of the expanded pipe portion c121 is horizontally formed and the swirler c130 is mounted, and an inclined surface c154 inclined toward the inside of the combustion chamber FR is formed at the end of the fork pipe c 153.
The comparative test was performed in the case where the remaining structure of the burner in the comparative example was almost the same as that of the example (fig. 2) to which the present invention was applied. The total fuel (LNG) supply amounts at the time of the test were 330Nm3/h and 260Nm3/h, and the amounts of change in nitrogen oxides (NOx) at different air (O2) supply amounts were measured according to the general test method (the same test method as in Table 1).
It can be seen from the graph that the low nitrogen oxide burner (fig. 2) equipped with the punched plate type burner head to which the embodiment of the present invention is applied has a reduction in the amount of nitrogen oxide (NOx) by about 40% as compared with the burner (fig. 6) equipped with the swirler type burner head in the comparative example.
In addition, the present invention can make maintenance and replacement of the burner head easier by adopting a structure in which the stage 1 fuel supply pipe 120 inside the stage 1 pipe 110 and the burner head 130 can be separated from the stage 1 fuel 110 alone. Further, the present invention can easily adjust the air passage area injected into the combustion chamber according to the combustion conditions by adopting a structure in which the stage 1 fuel supply pipe 120 and the combustion head 130 can be moved by the distance adjusting means 160. Regarding the position adjustment of the burner head 130, the stage 1 fuel supply pipe 120 fixed to the flange 161 and the burner head 130 can be adjusted in movement by pushing and pulling the connecting rod 162 by rotating the adjusting rod 163 outside the burner.
As described above, the low nox burner equipped with the punched plate type burner head to which the embodiment of the present invention is applied can be more easily repaired, replaced and adjusted, and can be applied to a smoke tube type boiler equipped with a combustion chamber structure in which reduction of nox is difficult to achieve because the volume of the combustion chamber is relatively small and the reduction of flame temperature is relatively slow, and can more effectively reduce the generation of nox. Further, the combustion stability of the burner can be ensured even when the gas fuel amount on the 1 st stage side is about 10% or less of the entire gas amount by means of the stable center flame, and the nitrogen oxides can be reduced by reducing the arrangement diameter of the 2 nd stage fuel injection body and increasing the inflow amount of the recirculated fuel gas.
While the invention has been described with reference to the embodiments illustrated in the drawings, the foregoing is for illustrative purposes only, and it will be appreciated by those skilled in the art that the invention may be embodied in other various modifications and equivalent embodiments. Therefore, the true technical scope of the present invention should be defined based on the technical ideas of the claims.
Claims (5)
1. A low nox burner equipped with a punch plate type burner head, comprising:
a stage 1 pipe installed to protrude toward the inside of the combustion chamber for guiding air to the inside of the combustion chamber;
a stage 1 fuel supply pipe disposed inside the stage 1 pipe for realizing stage 1 fuel supply;
a perforated plate type burner head disposed at a tip of the stage 1 fuel supply pipe at a predetermined distance from a tip of the stage 1 pipe, for radially injecting fuel supplied from the stage 1 fuel supply pipe while diffusing air guided by the stage 1 pipe;
a stage 2 pipe disposed so as to surround the stage 1 pipe, for guiding the unburned gas in the combustion chamber between the stage 1 pipes and injecting the gas into the combustion chamber;
a plurality of stage 2 fuel injection bodies arranged around the stage 2 pipe for injecting the stage 2 fuel;
a distance adjusting device for moving the punching plate type combustion head along the axial direction and adjusting the distance between the punching plate type combustion head and the tail end of the 1 st stage pipe;
a shaft diameter part provided with a section inclined at a specific angle to a punch plate type combustion head is formed at the front end part of the 1 st stage pipe; and
a plurality of interval maintaining ribs for guiding the movement of the punch plate type burner head and maintaining the interval between the punch plate of the punch plate type burner head and the shaft diameter part of the 1 st stage pipe,
the stage 1 pipe is connected to an air inducing pipe fixed to the wall of the combustion chamber for inducing air to the inside of the stage 1 pipe and the outside,
an inclined part inclined to the outer side surface of the 1 st stage pipe is formed in front of the air inducing pipe,
a combustion gas circulation interval for circulating the combustion gas of the combustion chamber and re-supplying the combustion gas into the combustion chamber is formed between the inclined portion and the 2 nd stage pipe,
the end of the nozzle pipe for injecting the 2 nd stage fuel in the 2 nd stage fuel injection body is provided with a fork pipe for flowing in and redirecting the combustion gas of the combustion chamber to be injected into the combustion chamber,
an inclined surface for injecting the mixture of the 2 nd-stage fuel and the combustion gas obliquely to the outside of the combustion chamber is formed at the end of the fork pipe.
2. The burner of low nox with a punch-plate type burner according to claim 1, wherein:
the distance adjusting device includes:
a flange fixed on the outer side surface of the 1 st stage fuel supply pipe;
a connecting rod connected to the flange; the method comprises the steps of,
and an adjusting rod coupled to the connecting rod, for adjusting the position of the level 1 fuel supply pipe by moving the level 1 fuel supply pipe.
3. The burner of low nox with a punch-plate type burner according to claim 1, wherein:
a plurality of 1 st support ribs for supporting the tube while aligning the center are provided between the 1 st tube and the 2 nd tube,
the inclined portion is provided with a plurality of 2 nd support ribs protruding toward the 2 nd pipe side and supporting the outer surface of the 2 nd pipe.
4. The burner of low nox with a punch-plate type burner according to claim 1, wherein:
an expansion pipe portion for diffusing the air at the combustion chamber side end portion to the outside of the combustion chamber is formed in the 2 nd stage pipe,
a support part for supporting the 2 nd stage fuel injection body is provided on the outer peripheral surface of the expansion part.
5. The burner of low nox with a punch-plate type burner according to claim 1, wherein:
the center length of the fork tube is more than 10 times of the inner diameter.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/KR2019/005491 WO2020226206A1 (en) | 2019-05-08 | 2019-05-08 | Low-nox burner having perforated plate-type combustion head |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112204307A CN112204307A (en) | 2021-01-08 |
| CN112204307B true CN112204307B (en) | 2023-08-04 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201980000915.3A Active CN112204307B (en) | 2019-05-08 | 2019-05-08 | Low NOx burner with punched plate type burner head |
Country Status (3)
| Country | Link |
|---|---|
| CN (1) | CN112204307B (en) |
| RU (1) | RU2743686C1 (en) |
| WO (1) | WO2020226206A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112984508B (en) * | 2021-02-24 | 2021-12-28 | 西安交通大学 | Hydrogen injection type ammonia low-nitrogen cyclone burner |
| CN115325536A (en) * | 2022-08-17 | 2022-11-11 | 东北大学 | Low NOx discharges nozzle |
Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB191112703A (en) * | 1911-05-26 | 1912-05-28 | Matthew Steel | Improvements in or connected with Blow Pipe Burners. |
| JPH05113206A (en) * | 1991-10-22 | 1993-05-07 | Sanyo Electric Co Ltd | Gas burner |
| JPH05215306A (en) * | 1991-04-16 | 1993-08-24 | Babu Hitachi Eng Service Kk | Divided flame type low nox gas burner |
| JPH11201416A (en) * | 1998-01-06 | 1999-07-30 | Chugai Ro Co Ltd | Exhaust gas circulation type low nox radiant tube burner |
| US6698207B1 (en) * | 2002-09-11 | 2004-03-02 | Siemens Westinghouse Power Corporation | Flame-holding, single-mode nozzle assembly with tip cooling |
| JP2004177037A (en) * | 2002-11-28 | 2004-06-24 | Osaka Gas Co Ltd | Combustion equipment |
| KR20130106778A (en) * | 2012-03-20 | 2013-09-30 | 주식회사 대열보일러 | A lo-nox burner of eco-friendly for nox decrease |
| CN104633655A (en) * | 2013-11-12 | 2015-05-20 | 韩国生产技术研究院 | Ultra-low nitrogen oxide combustion apparatus using internal recirculation of combustion gas and method therefor |
| KR101569455B1 (en) * | 2015-07-14 | 2015-11-16 | 주식회사 수국 | Complex burner for Low nitrogen oxide |
| CN105698172A (en) * | 2016-04-11 | 2016-06-22 | 徐州科融环境资源股份有限公司 | Petal-shaped staged combustion gas low-nitrogen combustor |
| JP2017181005A (en) * | 2016-03-31 | 2017-10-05 | 大阪瓦斯株式会社 | Gas burner and heating furnace including the same |
| CN107477580A (en) * | 2017-09-07 | 2017-12-15 | 温岭威索燃烧器有限公司 | Low NO |
| CN107477579A (en) * | 2016-06-08 | 2017-12-15 | 株式会社水国 | Low nitrogen oxide burner |
| CN107690557A (en) * | 2016-06-03 | 2018-02-13 | 韩国生产技术研究院 | Super low nitrogen oxide burning device |
| CN108738333A (en) * | 2017-02-23 | 2018-11-02 | 株式会社水国 | Compound low nitrogen oxide burner |
| CN109028058A (en) * | 2018-08-31 | 2018-12-18 | 上海华之邦科技股份有限公司 | A kind of flame-stabilising type low NO |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2008559C1 (en) * | 1991-04-15 | 1994-02-28 | Шестаков Николай Сергеевич | Method and device for burning gas |
| JP2537451B2 (en) * | 1992-09-22 | 1996-09-25 | 株式会社ヒラカワガイダム | Low NOx burner |
| CA2524760A1 (en) * | 2004-11-02 | 2006-05-02 | Babcock-Hitachi K.K. | After-air nozzle for two-stage combustion boiler, and a two-stage combustion boiler, boiler and combustion method using the same |
| KR101235638B1 (en) * | 2012-06-05 | 2013-02-21 | (주) 청우지엔티 | Low nox burner |
| KR101324945B1 (en) * | 2012-11-09 | 2013-11-04 | 주식회사 부-스타 | Low pressure low nox burner |
| KR101466809B1 (en) * | 2014-09-23 | 2014-11-28 | 주식회사 수국 | Burner head for Low nitrogen oxide and high efficiency and burner using the same |
| WO2017209503A1 (en) * | 2016-06-03 | 2017-12-07 | 한국생산기술연구원 | Ultra-low nitrogen oxide combustion apparatus |
| US11415317B2 (en) * | 2017-06-26 | 2022-08-16 | C.I.B. Unigas S.P.A. | Combustion head with low emission of NOx for burners and burner comprising such a head |
-
2019
- 2019-05-08 CN CN201980000915.3A patent/CN112204307B/en active Active
- 2019-05-08 WO PCT/KR2019/005491 patent/WO2020226206A1/en active Application Filing
- 2019-05-08 RU RU2020103391A patent/RU2743686C1/en active
Patent Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB191112703A (en) * | 1911-05-26 | 1912-05-28 | Matthew Steel | Improvements in or connected with Blow Pipe Burners. |
| JPH05215306A (en) * | 1991-04-16 | 1993-08-24 | Babu Hitachi Eng Service Kk | Divided flame type low nox gas burner |
| JPH05113206A (en) * | 1991-10-22 | 1993-05-07 | Sanyo Electric Co Ltd | Gas burner |
| JPH11201416A (en) * | 1998-01-06 | 1999-07-30 | Chugai Ro Co Ltd | Exhaust gas circulation type low nox radiant tube burner |
| US6698207B1 (en) * | 2002-09-11 | 2004-03-02 | Siemens Westinghouse Power Corporation | Flame-holding, single-mode nozzle assembly with tip cooling |
| JP2004177037A (en) * | 2002-11-28 | 2004-06-24 | Osaka Gas Co Ltd | Combustion equipment |
| KR20130106778A (en) * | 2012-03-20 | 2013-09-30 | 주식회사 대열보일러 | A lo-nox burner of eco-friendly for nox decrease |
| CN104633655A (en) * | 2013-11-12 | 2015-05-20 | 韩国生产技术研究院 | Ultra-low nitrogen oxide combustion apparatus using internal recirculation of combustion gas and method therefor |
| KR101569455B1 (en) * | 2015-07-14 | 2015-11-16 | 주식회사 수국 | Complex burner for Low nitrogen oxide |
| JP2017181005A (en) * | 2016-03-31 | 2017-10-05 | 大阪瓦斯株式会社 | Gas burner and heating furnace including the same |
| CN105698172A (en) * | 2016-04-11 | 2016-06-22 | 徐州科融环境资源股份有限公司 | Petal-shaped staged combustion gas low-nitrogen combustor |
| CN107690557A (en) * | 2016-06-03 | 2018-02-13 | 韩国生产技术研究院 | Super low nitrogen oxide burning device |
| CN107477579A (en) * | 2016-06-08 | 2017-12-15 | 株式会社水国 | Low nitrogen oxide burner |
| CN108738333A (en) * | 2017-02-23 | 2018-11-02 | 株式会社水国 | Compound low nitrogen oxide burner |
| CN107477580A (en) * | 2017-09-07 | 2017-12-15 | 温岭威索燃烧器有限公司 | Low NO |
| CN109028058A (en) * | 2018-08-31 | 2018-12-18 | 上海华之邦科技股份有限公司 | A kind of flame-stabilising type low NO |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112204307A (en) | 2021-01-08 |
| RU2743686C1 (en) | 2021-02-24 |
| WO2020226206A1 (en) | 2020-11-12 |
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