CN110056869B

CN110056869B - Burner

Info

Publication number: CN110056869B
Application number: CN201910153691.1A
Authority: CN
Inventors: 马晓阳; 邵松; 张猛; 王文奇; 乔亮
Original assignee: Luoyang Ruichang Environmental Engineering Co ltd
Current assignee: Luoyang Ruichang Environmental Engineering Co ltd
Priority date: 2019-02-28
Filing date: 2019-02-28
Publication date: 2024-09-24
Anticipated expiration: 2039-02-28
Also published as: CN110056869A

Abstract

The invention provides a combustor, which comprises a combustor cylinder, a primary fuel spray gun, a mixer, a secondary fuel spray gun and refractory bricks, wherein the mixer penetrates through the combustor cylinder, the primary fuel spray gun is connected to the bottom of the combustor cylinder, the primary fuel spray gun extends into an inlet at the lower part of the mixer through the bottom of the combustor cylinder, a mixing gas collection cavity is arranged at the top of the mixer, primary fuel gas adopts a premixed combustion technology, and the mixed gas of the primary fuel gas and combustion air is sprayed into a primary combustion zone for rapid combustion after being mixed in the mixing gas collection cavity. The fuel classification technology is adopted, the primary fuel adopts the premixing technology, the secondary fuel adopts the flue gas reflux technology, two independent gas regulating valves are arranged, a pressure gauge is arranged between the regulating valves and the burner, and the proportion of the primary fuel and the secondary fuel can be independently regulated and controlled according to the requirement. The problem of CO exceeding of low-temperature hearth flue gas is effectively solved, and the burnout rate is improved. Eliminating the potential safety hazard of the heating furnace.

Description

Burner

Technical Field

The invention belongs to the technical field of burner application for a tubular heating furnace, and mainly relates to a burner.

Background

With the rapid development of industries such as oil refining chemical industry, electric power, metallurgy and the like, an industrial tubular furnace has higher environmental protection requirement on a burner, and an ultralow NO _X burner is widely applied in the petrochemical industry.

The ultra low NO _X burner reduces the formation of thermal NO _X during combustion by reducing the flame zone temperature. The lower the flame zone temperature, the less NO _X is produced. However, in the practical application process, when the temperature of a heating furnace hearth is low and the temperature of the hearth is lower than 600 ℃, the ultralow NO _X burner is extremely easy to burn incompletely, a large amount of intermediate product CO is generated, and the incompletely burned CO in the hearth can detonate in a flame area to cause negative pressure fluctuation of the hearth. And when the combustion is serious, faults such as positive pressure of a hearth, insufficient combustion air, flameout of a burner and the like occur, and potential safety hazards exist.

The patent with the application number 201710097275.5 in the prior art discloses a bottom staged combustion low NOx gas burner, which comprises a bellows, refractory bricks, an ejector and a fuel gun, wherein the refractory bricks are arranged at the bottom of the furnace, the hollow part in the interior is an air flow passage, and the ejector penetrates through the bellows and stretches into the air flow passage; a duct is arranged between the refractory bricks and the furnace bottom, and the fuel gun passes through the bellows and the duct to extend into the hearth; the fuel gun is provided with a fuel spray head at the tail end, and the fuel gun sprays in two directions: spraying the mixture into an air flow channel through a through hole on the refractory brick and spraying the mixture to an outlet of the refractory brick parallel to the side wall of the refractory brick; the air box is internally provided with a baffle plate which divides the air box into an upper part and a lower part, the lower part is provided with a primary air door, the upper part is provided with a secondary air door, an air inlet of the ejector is positioned at the lower part of the air box, and the ejector ejection ratio is 25-41. The burner can effectively reduce the emission of nitrogen oxides by adopting a lean premixed technology and a staged combustion technology. However, in the actual use process, NO _X is required to realize low emission, and under the condition of low hearth temperature, fuel combustion is complete and sufficient, and the CO emission meets the normal operation requirement of the heating furnace.

Disclosure of Invention

In view of this, the present invention is specifically directed to solve the problem that the fuel combustion is insufficient and the CO emission does not meet the normal requirements when the NO _X is low.

In order to achieve the above purpose, the technical scheme of the invention is realized as follows:

The utility model provides a combustor, includes combustor barrel, one-level fuel spray gun, blender, second grade fuel spray gun, resistant firebrick, the blender passes the combustor barrel form barrel runner between combustor barrel and the blender, the fuel gas adopts the staged combustion technique, and every level fuel is all through independent governing valve individual control load combustor barrel connects one-level fuel spray gun bottom, one-level fuel spray gun stretches into blender lower part entrance through combustor barrel bottom the top of blender sets up the mixing gas collection chamber, and the one-level fuel gas adopts the premixed combustion technique, and the mixture of one-level fuel gas and combustion air is in after mixing the inside mixed gas collection chamber sprays into the one-level combustion zone and burns rapidly.

Further, the mixed gas collecting cavity is arranged in a ring shape or a cone shape, a mixed gas spray hole is arranged on the mixed gas collecting cavity, and the mixed gas spray hole is directly arranged on the mixed gas collecting cavity or led out through a branch pipe.

Further, the mixing gas collection cavity is connected with the mixer through a gas guide pipe, the gas guide pipe is divided into a vertical section and an inclined section, the inclined section is connected with the mixer, and the inclined section is inclined towards the direction close to the refractory bricks.

Further, the top of the inclined section is connected with a vertical section, and a mixed gas collection cavity is arranged at the top of the vertical section.

Further, a mixed gas collecting cavity is arranged at the connecting part of the top of the inclined section and the vertical section.

Further, the refractory brick is sequentially provided with an air inlet section, a transition section and an air outlet section from bottom to top, the air inlet section is provided with an air contraction flow passage with gradually smaller cross section area from bottom to top, the air outlet section is provided with a refractory material higher than the furnace bottom or the furnace wall and stretches into the furnace chamber section, the cross section area of the flow passage of the air outlet section can be kept unchanged, and also can be contracted or expanded, and the transition section is provided with a straight flow passage with unchanged cross section area.

Further, the mixed gas spray holes are uniformly arranged in the area surrounded by the refractory bricks along the circumference of the inner side of the refractory bricks, and the top parts of the mixed gas spray holes incline towards the direction close to the wall of the combustor cylinder.

Further, a duct is arranged between the refractory brick and the furnace bottom, the secondary fuel spray gun penetrates through the duct and stretches into the furnace chamber, and secondary fuel sprayed by the secondary fuel spray gun is mixed with combustion air and smoke generated by primary fuel for combustion.

Further, a secondary fuel gas collection cavity is arranged at the bottom of the burner cylinder, and the secondary fuel regulating valve is used for introducing secondary fuel into the secondary fuel gas collection cavity through a connecting pipeline.

Further, a heat-accumulating flame-stabilizing cover is arranged in the primary combustion area, the bottom of the heat-accumulating flame-stabilizing cover is arranged on the upper surface of the inner circumference of the mixed gas collection cavity, and the heat-accumulating flame-stabilizing cover can be divided into a plurality of parts which are respectively arranged at the heads of the branch pipes and extend to the direction close to the refractory bricks in parallel to the gas mixture spray heads.

Compared with the prior art, the burner provided by the invention has the following advantages:

The burner adopts a fuel classification technology, and the main fuel gas is divided into two stages. The primary fuel adopts a premixing technology. The primary fuel and the combustion air are mixed uniformly through venturi, so that the primary fuel can be combusted in a short time and can be completely combusted. Avoiding the formation of the process product CO of combustion.

The opening degree of the primary fuel regulating valve is regulated, so that the flow rate of primary fuel can be increased, the temperature of a combustor of a primary fuel combustion zone is further increased, and CO generation is reduced. Meanwhile, the secondary fuel can be ignited, so that the stable combustion of the secondary fuel is ensured, and the phenomenon of fire loss is avoided. The opening degree of the secondary fuel regulating valve can be regulated, so that the content of secondary fuel is increased, the smoke circulation quantity is further increased, the combustion flame temperature of the secondary fuel is controlled, and the generation of NO _X in the combustor is effectively controlled.

The burner is provided with two independent gas regulating valves, a pressure gauge is arranged between the regulating valves and the burner, and the proportion of primary fuel and secondary fuel can be independently regulated and controlled according to the requirement. Decreasing the secondary fuel increases the primary fuel, which may decrease CO. Increasing the secondary fuel and decreasing the primary fuel can reduce NO _X, and the on-site flexible adjustment can be performed according to actual emission data. The operating pressures of the primary fuel and the secondary fuel can be respectively regulated between 0.01 Mpa and 0.2 Mpa.

The problem of CO exceeding of low-temperature hearth flue gas is effectively solved, and the burnout rate is improved. Eliminating the potential safety hazard of the heating furnace.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention. In the drawings:

FIG. 1 is a schematic view of a burner according to an embodiment of the present invention;

FIG. 2 is a top view of the burner according to an embodiment of the present invention;

FIG. 3 is a schematic view of a burner according to a second embodiment of the present invention;

FIG. 4 is a top view of a burner according to a second embodiment of the invention;

FIG. 5 is a schematic view of a burner according to a third embodiment of the present invention;

FIG. 6 is a schematic view of a three-dimensional structure of a catalytic bed according to a third embodiment of the present invention;

fig. 7 is a top view of a catalytic bed according to a third embodiment of the present invention.

Reference numerals illustrate:

1. Primary fuel lance, 2, burner cylinder, 3, venturi mixer, 4, secondary fuel lance, 5, mixed gas collecting chamber, 6, mixed gas injection orifice, 7, refractory brick, 8, secondary fuel collecting chamber, 9, secondary fuel regulating valve, 10, primary fuel regulating valve, 11, air regulating baffle, 12, pilot burner, 13, furnace bottom, 14, furnace, 15, gas tee, 16, air inlet, 17, primary combustion zone, 18, gas duct, 19, vertical section, 20, inclined section, 21, set screw, 22, air inlet section, 23, transition section, 24, air outlet section, 25, cylinder flow passage, 26, connection, 27, heat accumulating flame stabilizing cap, 28, branch pipe, 29, catalytic bed, 30, flank, 31, bottom plate, 32, support

Detailed Description

The following describes in further detail the embodiments of the present invention with reference to the drawings and examples. The following examples are illustrative of the invention and are not intended to limit the scope of the invention.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

Example 1

As shown in fig. 1 and 2, the present embodiment provides a burner comprising main components of a burner cylinder 2, a primary fuel lance 1, a mixer 3, a secondary fuel lance 4, a mixing gas collection chamber 5, a gas mixture nozzle 6, refractory bricks 7, a secondary fuel collection chamber 8, a secondary fuel regulating valve 9, a primary fuel regulating valve 10, an air regulating baffle 11, a pilot lamp 12, and the like.

The refractory brick 7 is sequentially provided with an air inlet section 22, a transition section 23 and an air outlet section 24 from bottom to top, wherein the air inlet section 22 is provided with an air contraction flow passage with the cross section area gradually reduced from bottom to top, the transition section 23 is a straight flow passage with the constant cross section area, the air outlet section 24 is provided with a refractory material higher than the furnace bottom or the furnace wall and extends into the hearth section, and the flow passage cross section area of the air outlet section 24 can be kept unchanged and can also be contracted or expanded. The air inlet section 22 is arranged in a structure that the cross section area is gradually reduced from bottom to top, so that combustion air can smoothly enter an air flow passage formed by the refractory bricks 7 from the barrel flow passage 25, and then the combustion air passes through the flat transition section 23, reaches the hearth 14 through the air outlet section 24 and is mixed with secondary fuel for combustion.

Wherein the burner cylinder 2 is provided in a cylindrical configuration and the burner is mounted to the furnace floor 13 by means of set screws 21. A mixer 3 for mixing fuel and air is provided inside the burner cylinder 2. A primary fuel lance 1 is arranged at the bottom of the burner cylinder 2, said primary fuel lance 1 extending into the burner cylinder 2 through the bottom of the burner cylinder 2. And the primary fuel spray gun 1 is arranged concentrically with the mixer 3 inside the burner cylinder 2, and the primary fuel spray gun 1 extends to the inlet of the lower part of the mixer 3 and is communicated with the inside of the mixer 3. Preferably, the mixer 3 is configured as a venturi mixer, which facilitates adequate mixing of fuel and air.

A mixing gas collection cavity 5 is arranged near the upper part of the venturi mixer 3, and the mixing gas collection cavity 5 is connected with the venturi mixer 3 through a gas guide pipe 18. The air duct 18 is divided into a vertical section 19 and an inclined section 20, the inclined section 20 is connected with the Venturi mixer 3, the inclined section 20 is inclined towards the direction close to the refractory bricks 7, the top of the inclined section 20 is connected with the vertical section 19, the vertical section 19 extends upwards parallel to the cylinder wall of the burner, and the top of the vertical section 19 is connected with the gas mixture collecting cavity 5. Preferably, the gas mixture collection chamber 5 may be provided in a circular ring-shaped or a conical structure.

Further, a plurality of fuel mixture injection holes 6 are provided in the mixture gas collecting chamber 5. And the mixture gas injection holes 6 may be provided to open directly into the mixture gas collection chamber 5. The primary fuel and the air sucked into the venturi mixer 3 after being injected by the primary fuel are completely mixed, pass through the mixed gas collecting cavity 5 and are sprayed and combusted through the plurality of mixed gas spray holes 6. The arrangement of the gas mixture gas collecting cavity 5 ensures that fuel can be fully mixed before combustion, the uniformity of mixing is improved, the flow area of combustion air mixed with primary fuel in the gas mixture gas collecting cavity 5 is rapidly reduced when the combustion air passes through the gas mixture gas spray holes 6, the wind speed of the gas mixture is rapidly increased, the sprayed primary combustion fuel can be rapidly sprayed, the uniform flame temperature is ensured, meanwhile, the generation of local high temperature can be prevented, and the generation of NOX is well inhibited.

Further, the gas mixture spray holes 6 are uniformly arranged inside the refractory bricks 7 along the circumference of the inner side of the refractory bricks 7, and the gas mixture spray holes 6 are also arranged in an inclined structure, the top of the gas mixture spray holes is inclined towards the direction close to the wall of the burner cylinder, so that the primary combustion area 17 after primary fuel is sprayed out is reduced, and the gas mixture spray holes can be rapidly combusted. The premixed combustion technology adopted by the primary fuel combustion not only can enable the primary fuel to complete combustion in a short time, but also can completely burn. Avoiding the formation of the process product CO of combustion.

An air inlet 16 is formed in the position, close to the bottom, of the burner cylinder 2, and air in the external environment enters the burner cylinder through the air inlet 16 to participate in combustion. An air adjusting baffle 11 is arranged in the air inlet, and the air inlet quantity is adjusted by adjusting the rotating angle of the air adjusting baffle 11, so that the reasonable adjustment of the fuel and air proportion in the combustor is realized.

Further, an air conditioning damper 11 is connected to the burner cylinder 2, and forms an air passage together with the refractory bricks 7 above the burner cylinder 2. After combustion air enters the combustor cylinder 2 through the air conditioning baffle 11, a part of air enters the venturi mixer 3 under the ejection effect of primary fuel gas. The other part of the air is introduced into an air flow passage formed by refractory bricks 7 through a barrel flow passage 25 formed between the outer side of the Venturi mixer 3 and the burner barrel 2, and is injected into the primary combustion zone through the refractory bricks 7 and then introduced into the hearth 14.

Further, a duct is arranged between the refractory brick 7 and the furnace bottom 13, the secondary fuel spray gun 4 penetrates through the duct between the refractory brick 7 and the furnace bottom 13 and stretches into the hearth 14, and secondary fuel sprayed by the secondary fuel spray gun 4 is mixed with combustion air and smoke generated by primary fuel for combustion. Due to the effect of the Venturi mixer 3, the primary fuel combustion area is lean-burn premixed combustion, excessive oxygen is supplied, the oxygen content of the generated flue gas is high, the flue gas can be used as combustion-supporting air of secondary fuel, the flue gas circulates, the flame stability is good, the effect of reducing the oxygen concentration and the temperature of the combustion area is achieved, and the generation of NOx is greatly restrained.

Further, a fuel gas supply system is connected to the bottom of the burner cylinder 2, specifically, the main fuel gas is divided into two paths through a gas tee 15, one path is connected with the primary fuel spray gun 1 and introduced into the venturi mixer 3, and the other path is connected with the air inlet end of the secondary fuel.

Furthermore, the fuel gas adopts a staged combustion technology, and each fuel gas is provided with an independent fuel regulating valve to independently control the load. A primary fuel regulating valve 10 is arranged on a connecting pipeline connected with the primary fuel spray gun 1 and is used for regulating the air inflow of primary fuel, thereby realizing the regulation of the proportion of the primary fuel and the combustion air.

The secondary fuel regulating valve 9 is arranged on a connecting pipeline connected with the inlet end of the secondary fuel after passing through the gas tee 15, and the distribution ratio of the primary fuel and the secondary fuel is further regulated by regulating the secondary fuel regulating valve 9. Further, the fuel gas supply system further comprises a secondary fuel gas collection cavity 8, wherein the secondary fuel gas collection cavity 8 is arranged at the bottom of the burner cylinder 2 and is connected with the burner cylinder 2 through connecting parts 26 at two sides, so that the installation stability of the secondary fuel gas collection cavity 8 is improved. The secondary fuel regulating valve 9 is used for introducing secondary fuel into the secondary fuel gas collection cavity 8 through a connecting pipeline, wherein a secondary fuel inlet is arranged on the secondary fuel gas collection cavity 8. Wherein the secondary fuel inlet is arranged at the lower part of the secondary fuel gas collection cavity 8 and is connected with the secondary fuel regulating valve 9 through a connecting pipeline.

The secondary fuel gas collection cavity 8 is also provided with a plurality of secondary fuel outlets, and the plurality of secondary fuel spray guns 4 are communicated with the secondary fuel gas collection cavity 8 through the secondary fuel outlets, so that the secondary fuel spray guns 4 are uniformly arranged outside the refractory bricks 7 along the circumference of the burner cylinder 2. Preferably, the number of secondary fuel spray guns is more than 3, each of which passes through the interior of the burner cylinder 2, and the heads of the secondary fuel spray guns extend out of the refractory bricks 7 to expose the hearth plane. So that the secondary fuel is sprayed above the burner tile 7 to be burnt after contacting with air.

Furthermore, a pilot burner 12 is also arranged in the burner cylinder 2, and the pilot burner 12 adopts independent fuel gas and is not influenced by the environment of the hearth 14.

Further, a heat-accumulating flame-stabilizing cover 27 is arranged in the primary combustion area 17, the bottom of the heat-accumulating flame-stabilizing cover 27 is arranged on the upper surface of the inner circumference of the mixed gas collection cavity 5, and the heat-accumulating flame-stabilizing cover 27 can be divided into a plurality of parts which are respectively arranged at the heads of the branch pipes, and the heat-accumulating flame-stabilizing cover 27 extends parallel to the direction of the mixed gas nozzle approaching to the refractory bricks 7. The burner is used for ensuring that primary fuel and combustion air circulate upwards along the inner wall surface of the refractory brick 7 for combustion, has a stabilizing effect on the flame root, and effectively controls the generation of NO _X in the burner.

The combustor provided by the embodiment divides the air flow passage formed by the refractory bricks into three sections, is beneficial to circulation and acceleration of combustion air, ensures that secondary fuel can be fully combusted, and effectively controls NO _X to be generated. On the other hand, the mixing uniformity of the primary fuel and the combustion air is improved through the arrangement of the mixing gas collection cavity, so that the primary fuel can be rapidly combusted, the uniform flame temperature is ensured, meanwhile, the generation of local high temperature can be prevented, and the generation of NO _X is well inhibited.

The main fuel gas is divided into two stages by adopting a fuel classification technology. The primary fuel adopts a premixing technology, and the secondary fuel adopts a flue gas reflux technology. The primary fuel and the combustion air are mixed uniformly through venturi, so that the primary fuel can be combusted in a short time and can be completely combusted. Avoiding the formation of the process product CO of combustion.

Furthermore, by adjusting the opening of the primary fuel adjusting valve, the flow rate of the primary fuel can be increased, so that the temperature of the burner in the primary fuel combustion zone is increased, and the generation of CO is reduced. Meanwhile, the secondary fuel can be ignited, so that the stable combustion of the secondary fuel is ensured, and the phenomenon of fire loss is avoided. The opening degree of the secondary fuel regulating valve can be regulated, so that the content of secondary fuel is increased, the smoke circulation quantity is further increased, the combustion flame temperature of the secondary fuel is controlled, and the generation of NO _X in the combustor is effectively controlled.

The burner is provided with two independent gas regulating valves, a pressure gauge is arranged between the regulating valves and the burner, and the proportion of primary fuel and secondary fuel can be independently regulated and controlled according to the requirement. Decreasing the secondary fuel increases the primary fuel, which may decrease CO. Increasing the secondary fuel and decreasing the primary fuel can reduce NOX, and the site can be flexibly adjusted according to actual emission data. The operating pressures of the primary fuel and the secondary fuel can be respectively regulated between 0.01 Mpa and 0.2 Mpa.

After the burner described in example 1 was normally operated for 48 hours, the furnace temperature, the oxygen content in the inside, the NO _X discharge amount, and the CO discharge amount of the burner were measured and recorded.

Example 2

As shown in fig. 3 and 4, the present invention may be modified to a burner comprising a burner cylinder 2, a primary fuel lance 1, a mixer 3, a secondary fuel lance 4, a gas mixture nozzle 6, a refractory brick 7, a secondary fuel gas collection chamber 8, a secondary fuel regulating valve 9, a primary fuel regulating valve 10, an air regulating baffle 11, a pilot lamp 12, and the like. Preferably, the mixer is configured as a venturi mixer to facilitate adequate mixing of fuel and air.

The venturi mixer 3 is connected with the air duct 18 at a position close to the top, the air duct 18 is divided into a vertical section 19 and an inclined section 20, the inclined section 20 is connected with the venturi mixer 3, the inclined section 20 is inclined towards the direction close to the refractory bricks 7, and the part of the top of the inclined section 20 connected with the vertical section 19 is provided with the gas mixture collecting cavity 5. The mixture gas jet hole 6 is led out from the upper part of the mixture gas collecting cavity 5 through a plurality of branch pipes 28, and the mixture gas of the primary fuel and the combustion air is jetted obliquely upwards through the mixture gas jet hole 6 and burnt.

The specific structure of other parts of the burner in this embodiment is the same as that of embodiment 1, and will not be described here again.

Example 3

As shown in fig. 5 to 7, this embodiment further improves the structure of the mixed gas collection chamber 5 on the basis of the above embodiment 2, and a catalytic bed layer is provided at the connection portion between the mixer 3 and the gas duct 18, so that the fuel gas molecules and the oxidant molecules in the combustion air react on the surface of the catalyst with a relatively low activation energy, and the fuel gas is ensured to be burned rapidly and sufficiently.

Specifically, the catalytic bed 29 is configured in a frustoconical configuration, including a side wing 30 and a middle bottom plate 31, with catalyst attached to both the side wing 30 and the bottom plate 31. The bottom plate 31 is provided in a disk shape or other structure matching the shape of the mixer, and the bottom plate 31 is clamped at the upper part of the mixer. The side wings 30 extend into the inside of the gas guide tube 18, and the side wings 30 are provided in a strip-shaped plate-like structure and are provided as perforated plates, and the shape and size of the holes are set according to the flow rate of the fuel gas, the operating conditions of the burner, and the like. The top ends of the side wings 30 are provided with connecting pieces for hanging the catalytic bed layer 29 against the air duct, so as to ensure the connection of the catalytic bed layer 29 and the burner.

The thickness and width of the wings 30 are set according to the size of the inner diameter of the airway tube 18 to avoid occluding the airway tube. The number of the side wings 30 is not more than that of the air ducts 18, so that the fuel gas entering the mixed gas collection cavity 5 through the air ducts 18 can pass through the catalytic bed layer, and the activation energy of the mixed gas collection cavity is sufficiently reduced.

Further, in order to prevent the catalyst on the side wings 30 and the bottom plate 31 from falling off and thus to affect the subsequent reaction of the fuel gas and the combustion air, the present embodiment provides a mesh layer at the lower portions of the side wings 30 and the bottom plate 31, allowing the fuel gas and the combustion air to pass therethrough while having a certain supporting effect on the catalyst.

Further, the lower portion of the side wing 30 is further connected with a supporting member 32, the lower portion of the supporting member 32 is abutted to the outer wall of the air duct 18, and the supporting member 32 is in an iron wire structure, so that smooth passing of fuel gas and combustion air is ensured, and the supporting member is matched with a connecting member for use, so that connection stability of the catalytic bed 29 and the burner is further improved.

The burner provided in this embodiment combines the staged combustion technology, the flue gas recirculation technology and the catalytic combustion technology on the basis of the above embodiments, and has a stronger inhibition effect on the generation of NO _X and CO while ensuring that the fuel can be fully and completely combusted.

Example 4

The invention also discloses a combustion method of the burner, which comprises the following steps:

S1: opening the primary fuel regulating valve 10 to introduce primary fuel into the venturi mixer 3 through the primary fuel lance 1; simultaneously, an air conditioning baffle 11 is opened, part of combustion air is adsorbed into the venturi mixer 3 through the low-pressure adsorption effect of the venturi mixer 3 and flows upwards, gas in the venturi mixer 3 enters the mixed gas collection cavity 5 through a gas guide pipe 18, primary fuel and combustion air are fully mixed, and the mixed gas after uniform mixing is sprayed out through a mixed gas spray head 6 and is combusted once at an air outlet section 24 close to the inner wall of the refractory brick 7;

wherein the ratio of primary fuel to air in the venturi mixer 3 is 1: (9-12).

S2: another portion of the combustion air, which enters the barrel flow channel 25 through the air inlet 16 and is not absorbed by the venturi mixer 3, enters the inside of the furnace 14;

S3: the secondary fuel regulating valve 9 is opened, secondary fuel is introduced into the secondary fuel gas collecting cavity 8, the secondary fuel is sprayed out through a spray head at the top end of the secondary fuel spray gun 4, enters into the hearth 14 along the inner part of the refractory brick 7, and is mixed with combustion air which does not pass through the Venturi mixer and primary combustion flue gas for secondary combustion.

The burner combustion method provided by the embodiment adopts a method of fully mixing the primary fuel and the air before primary combustion, ensures that the primary fuel and the oxygen can be fully and uniformly mixed, quickly and completely burns in a short time, and avoids CO generation in the combustion process. And the flow of the secondary fuel is controlled, the temperature of the secondary combustion flame is controlled, and the generation of NO _X in the combustion process is effectively controlled.

Comparative example

The setting of the mixed gas collecting chamber 5 in example 1 was canceled, and the mixed gas passing through the venturi mixer was directly ejected through the gas guide pipe and the mixed gas ejection head 6 to burn. After 48 hours of normal operation of the burner, the burner furnace temperature, the internal oxygen content, the NO _X emissions and the CO emissions were measured and recorded.

The furnace temperature, the internal oxygen content, the NO _X emission amount, and the CO emission amount measured in comparative example 1 and comparative example were as follows:

	Furnace temperature/°c	Internal oxygen content%	NO _X emissions/ppm	CO emissions/ppm
					Example 1	550～630	≤3	28～32	1～7
Example 3	540～630	≤3	20～27	≤4
					Comparative example	600～670	3	33～35	48～170

As can be seen from the comparison between the embodiment 1 and the comparative example, the burner provided by the invention adopts the combination of the fuel staged combustion technology and the flue gas recirculation technology, can fully reduce the furnace temperature, can ensure that the fuel can fully and completely burn under the condition of low furnace temperature, can inhibit the generation of NO _X and CO, can meet the safe operation requirement of a heating furnace, and can ensure that the burner can normally and stably run.

As can be seen from a comparison of example 1 and example 3, the combination of staged combustion technology, flue gas recirculation technology, and catalytic combustion technology ensures that the fuel is fully combusted while further reducing the levels of NO _X and CO.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.

Claims

1. The utility model provides a combustor, includes combustor barrel (2), one-level fuel spray gun (1), blender (3), second grade fuel spray gun (4), resistant firebrick (7), blender (3) pass combustor barrel (2) form barrel runner (25) between combustor barrel (2) and blender (3), characterized in that, the fuel gas adopts staged combustion technique, and every level fuel is through independent governing valve individual control load, connect one-level fuel spray gun (1) in combustor barrel (2) bottom, one-level fuel spray gun (1) stretches into to blender (3) lower part entrance through combustor barrel (2) bottom, set up mixing gas collection chamber (5) in the top of blender (3), one-level fuel gas adopts premixed combustion technique, and the mixture of one-level fuel gas and combustion air is in mixing gas collection chamber (5) internal mixing back and is sprayed into one-level combustion zone (17) and is quick burning, mixing gas collection chamber (5) are connected with blender (3) through air duct (18), air duct (18) divide into vertical section (19) and incline section (20), incline section (20) and incline section (20) are connected to incline section (20) in the direction of incline section (20), the vertical section (19) extends upwards parallel to the cylinder wall of the burner, a mixed gas collecting cavity (5) is arranged at the position, connected with the vertical section (19), of the top of the inclined section (20), a plurality of fuel mixed gas spray holes (6) are arranged on the mixed gas collecting cavity (5), the mixed gas collecting cavity (5) is arranged in a circular ring shape or a conical shape, the mixed gas spray holes (6) are directly arranged on the mixed gas collecting cavity (5) or led out through a branch pipe, primary fuel and air sucked into the mixer (3) after being ejected by the primary fuel are completely mixed and then pass through the mixed gas collecting cavity (5) and are sprayed and combusted by the mixed gas spray holes (6), the mixed gas spray holes (6) are uniformly arranged in the area surrounded by the refractory bricks (7) along the circumference of the inner side of the refractory bricks (7), the top of the mixed gas spray holes (6) incline towards the direction close to the cylinder wall of the burner,

The catalytic bed is arranged at the connecting part of the mixer (3) and the air duct (18), the catalytic bed (29) is of a frustum structure, the catalytic bed (29) comprises a side wing (30) and a middle bottom plate (31), a catalyst is adhered to the side wing (30) and the bottom plate (31), the bottom plate (31) is of a disc shape, the bottom plate (31) is clamped at the upper part of the mixer, the side wing (30) stretches into the air duct (18), the side wing (30) is of a strip-shaped plate structure and is provided with a porous plate, a connecting piece is arranged at the top end of the side wing (30) and used for hanging the catalytic bed (29) on the air duct, a grid layer is arranged at the lower parts of the side wing (30) and the bottom plate, a supporting piece (32) is further connected to the lower part of the side wing (30), the lower part of the supporting piece (32) is abutted to the outer wall of the air duct (18), and the supporting piece (32) is of an iron wire-shaped structure;

The heat-accumulating flame-stabilizing cover (27) is arranged in the primary combustion area (17), the bottom of the heat-accumulating flame-stabilizing cover (27) is arranged on the upper surface of the inner circumference of the mixed gas collection cavity (5), or the heat-accumulating flame-stabilizing cover (27) is divided into a plurality of parts which are respectively arranged at the heads of the branch pipes, and the heat-accumulating flame-stabilizing cover (27) extends in the direction approaching to the refractory bricks (7) in parallel to the mixed gas spray nozzle.

2. Burner according to claim 1, characterized in that the refractory brick (7) is provided with an air inlet section (22), a transition section (23) and an air outlet section (24) from bottom to top, the air inlet section (22) is provided with an air contraction flow channel with gradually decreasing cross-sectional area from bottom to top, the air outlet section (24) is provided with a refractory material higher than the furnace bottom or the furnace wall and extends into the furnace (14), the cross-sectional area of the air outlet section (24) can be kept unchanged and can also contract or expand, and the transition section (23) is provided with a straight flow channel with unchanged cross-sectional area.

3. Burner according to claim 1, characterized in that between the refractory brick (7) and the furnace bottom (13) a duct is provided through which the secondary fuel lance (4) extends into the furnace (14), the secondary fuel sprayed by the secondary fuel lance (4) being combusted in combination with combustion air and flue gases from the primary fuel.

4. A burner according to claim 3, characterized in that a secondary fuel collection chamber (8) is provided at the bottom of the burner cylinder (2), and that a secondary fuel regulating valve (9) opens secondary fuel into the interior of said secondary fuel collection chamber (8) via a connecting line.