CN114623436A

CN114623436A - Mixed combustion discharging device of water-coal slurry boiler

Info

Publication number: CN114623436A
Application number: CN202210307722.6A
Authority: CN
Inventors: 袁永功; 秦泽元; 张刚; 孙钊伟; 刘杰; 刘光辉
Original assignee: Qingdao Shun'an Thermal Power Co ltd
Current assignee: Qingdao Shun'an Thermal Power Co ltd
Priority date: 2022-03-25
Filing date: 2022-03-25
Publication date: 2022-06-14

Abstract

The invention discloses a mixed combustion discharging device of a water-coal-slurry boiler, which comprises: the fuel inlet pipe is fixedly installed in the hearth close to the axis, the throat is arranged in the hearth, an internal circulation component is fixedly installed at one end, located at the throat, in the hearth and comprises a flue gas inlet, a second outlet and a first outlet, the first outlet is located at one end of the throat, the second outlet is opposite to the combustion chamber, and the flue gas inlet is located on the outer sides of the second outlet and the first outlet and opposite to the combustion chamber; a fan; a burner head; a combustion chamber; according to the invention, the internal circulation assembly is arranged, and the flue gas in the combustion chamber enters the internal circulation assembly along the flue gas inlet and the first outlet, is mixed with the combustion-supporting air and then flows out through the second outlet, so that the mixing of the combustion-supporting air and the internal circulation flue gas between the first outlet and the second outlet is realized, the combustion temperature and the oxygen content can be reduced, and the emission of NOx can be greatly reduced.

Description

Mixed combustion discharging device of water-coal slurry boiler

Technical Field

The invention relates to the technical field of coal water slurry boilers, in particular to a mixed combustion discharge device of a coal water slurry boiler.

Background

The coal-based clean fuel coal water slurry for burning the circulating fluidized bed boiler is an effective combustion mode for reducing smoke pollutants, a low-nitrogen combustor and smoke external circulation technical route is adopted for natural gas fuel at present, the emission of NOX can be reduced to 30mg/Nm3, the emission requirement of the current strictest environmental standard is met, and a smoke recirculation technology is that partial smoke (low-temperature section) is extracted from a tail flue of the boiler and mixed with combustion air and then sent into a hearth for combustion, so that the combustion temperature and the oxygen content can be reduced, and the emission of the NOX can be greatly reduced.

However, the low-temperature flue gas participating in the external circulation needs to be led out from the tail part of the boiler, and necessary flue gas recirculation components such as a flue gas recirculation pipeline, a flue gas mixing box, a recirculation fan and the like need to be additionally arranged, so that the structure is relatively complex, and the setting cost is high.

Disclosure of Invention

The invention aims to provide a mixed combustion discharge device of a water-coal-slurry boiler, which aims to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: the mixed combustion discharging device of the water coal slurry boiler comprises:

the fuel inlet pipe is fixedly installed in the hearth close to the axis, the throat is arranged in the hearth, an internal circulation component is fixedly installed at one end, located at the throat, in the hearth and comprises a flue gas inlet, a second outlet and a first outlet, the first outlet is located at one end of the throat, the second outlet is opposite to the combustion chamber, and the flue gas inlet is located on the outer sides of the second outlet and the first outlet and opposite to the combustion chamber;

a fan;

a burner head;

a combustion chamber;

the fan is fixedly installed at the bottom end of the hearth, the combustion chamber is fixedly connected to one end of the hearth, and the head of the combustor is fixedly connected to one end of the combustion chamber.

Preferably, the method further comprises the following steps:

mounting a plate;

the mounting plate is fixedly mounted outside the hearth, and screw holes are formed in four corners of the outer wall of the mounting plate.

Preferably, the method further comprises the following steps:

a base;

wherein, the base is fixedly arranged on the surface of the bottom end of the hearth.

Preferably, the burner head includes an outer sleeve and a main fuel pipe, the outer sleeve is sleeved outside the main fuel pipe, the main fuel pipe is axially provided with a plurality of rows of primary fuel holes, a combustion-supporting air hole corresponding to each primary fuel hole is arranged on the outer wall surface of the outer sleeve, and each primary fuel hole is fixedly provided with an injection mechanism, and the injection mechanism extends into the combustion-supporting air hole.

Preferably, the surface of one end, close to the combustion chamber, of the hearth is provided with an internal circulation flue gas inlet and a fuel port, the internal circulation flue gas inlet is located on two sides of the fuel port, and the internal circulation flue gas inlet is communicated with the flue gas inlet.

Preferably, the inner circulation assembly further comprises a first guide plate and a second guide plate, the first guide plate is fixedly connected with the throat, a flue gas channel is formed between the second guide plate and the first guide plate, and the flue gas channel is respectively communicated with the flue gas inlet and the first outlet.

Preferably, a flame nozzle is fixedly installed at one side of the fuel port in the combustion chamber, and the flame nozzle is fixedly connected with the hearth.

Preferably, one end of the main fuel pipe extends to the outside of the outer sleeve and is fixedly connected with a main fuel pipe end, a secondary fuel hole is formed in the surface of the outer wall of the main fuel pipe end, fuel is arranged in the main fuel pipe, and combustion-supporting air is arranged in the outer sleeve.

Preferably, a deflector for guiding the flow of the combustion-supporting air is arranged at the end of the main fuel pipe.

Preferably, the air inlet pipe is fixedly connected to the two sides of the fuel inlet pipe inside the hearth, a fuel channel is arranged inside the fuel inlet pipe, and one end of the fuel inlet pipe is fixedly connected with a fuel nozzle.

Compared with the prior art, the invention has the beneficial effects that:

1. the internal circulation assembly is arranged, so that the cross section area of the internal circulation assembly is smaller than that of the throat, the air flow rate and the dynamic pressure are increased, a relatively negative pressure atmosphere is created at the first outlet, the flue gas in the combustion chamber enters the internal circulation assembly along the flue gas inlet and the first outlet, is mixed with the combustion-supporting air and then flows out through the second outlet, the combustion-supporting air and the internal circulation flue gas are mixed between the first outlet and the second outlet, the combustion oxygen content of the fuel in the hearth is reduced, the combustion temperature and the oxygen content are reduced, and the emission of NOx can be greatly reduced.

2. According to the invention, through the installed burner head, combustion air and fuel are mixed through each micro-channel to form a flame, and a plurality of micro-channels are combusted to form a plurality of strands of distributed flames, so that a plurality of uniform distributed flames are formed at the outlet of the micro-channels, the ultralow emission of NOx is realized, the defects of a premixed combustion technology can be solved, and potential safety hazards such as tempering, flame holding and the like caused by the high flame propagation speed of the premixed combustion technology can be prevented.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the internal structure of the present invention;

FIG. 3 is a schematic view of the burner head construction of the present invention;

FIG. 4 is a schematic view of the internal structure of the burner head of the present invention;

FIG. 5 is a schematic view of the internal circulation assembly of the present invention;

fig. 6 is an enlarged structural diagram a of the present invention.

In the figure: 10. a hearth; 11. a fuel inlet pipe; 12. an air inlet pipe; 13. an internal circulation assembly; 131. a first guide plate; 132. a flue gas inlet; 133. a second outlet; 134. a second guide plate; 135. a first outlet; 136. a flue gas channel; 14. an internal circulation flue gas inlet; 15. a fuel port; 16. a fuel mixing chamber; 17. a fuel passage; 18. a fuel injector; 20. a fan; 30. mounting a plate; 40. a burner head; 41. an outer sleeve; 42. a primary fuel pipe; 43. combustion air; 44. a fuel; 45. a combustion-supporting air hole; 46. a main fuel pipe end; 461. a secondary fuel orifice; 47. a flow guide disc; 48. a primary fuel orifice; 49. an injection mechanism; 50. a base; 60. a combustion chamber; 61. a flame nozzle.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

referring to fig. 1-6, the present invention provides a technical solution: the mixed combustion discharging device of the water coal slurry boiler comprises: a furnace 10, a fan 20, a burner head 40 and a combustion chamber 60.

Further, the blower 20 is used for inputting combustion air into the furnace 10.

Wherein, a fuel inlet pipe 11 is fixedly arranged in the hearth 10 near the axle center, a throat is arranged in the hearth 10, an inner circulation assembly 13 is fixedly arranged at one end of the throat inside the hearth 10, the inner circulation assembly 13 comprises a flue gas inlet 132, a second outlet 133 and a first outlet 135, the cross-sectional area of the section formed by the first outlet 135 is smaller than that of the section formed by the second outlet 133, the cross-sectional area of the section formed by the second outlet 133 is smaller than that of the outlet of the throat, thus, the flow velocity of the combustion air and the internal circulation flue gas at the first outlet 135 can be maximized, and then the flow velocity is reduced, so that the combustion air and the internal circulation flue gas are mixed more fully, and finally the fully mixed low-oxygen air is discharged from the second outlet 133, the first outlet 135 is located at one end of the throat, the second outlet 133 is opposite the combustion chamber 60, the flue gas inlet 132 is located outside the second outlet 133 and the first outlet 135 and opposite the combustion chamber 60.

Further, the opening direction of the first outlet 135 is consistent with the flow direction of the combustion air, so that the internal circulation flue gas flowing out of the first outlet 135 is prevented from being mixed with the combustion air in a non-parallel manner, and the advancing resistance of the combustion air is increased.

Further, the cross-sectional area of the internal circulation assembly 13 is made smaller than that of the throat, the air flow rate and the dynamic pressure are increased, so that an atmosphere with relative negative pressure is created at the first outlet 135, the flue gas in the combustion chamber 60 enters the inside of the internal circulation assembly 13 along the flue gas inlet 132 and the first outlet 135, is mixed with the combustion air and then flows out through the second outlet 133, the mixing of the combustion air and the internal circulation flue gas between the first outlet 135 and the second outlet 133 is realized, the combustion temperature and the oxygen content can be reduced, and the emission of NOx can be greatly reduced.

The fan 20 is fixedly installed at the bottom end of the hearth 10, the combustion chamber 60 is fixedly connected to one end of the hearth 10, and the burner head 40 is fixedly connected to one end of the combustion chamber 60.

Wherein, still include: and a mounting plate 30.

The mounting plate 30 is fixedly mounted outside the hearth 10, and screw holes are formed in four corners of the outer wall of the mounting plate 30.

Further, the mounting stability of the apparatus can be improved by the mounting plate 30.

Wherein, still include: a base 50.

Wherein, the base 50 is fixedly installed on the bottom end surface of the hearth 10.

The surface of one end of the hearth 10 close to the combustion chamber 60 is provided with an internal circulation flue gas inlet 14 and a fuel port 15, the internal circulation flue gas inlet 14 is positioned at two sides of the fuel port 15, and the internal circulation flue gas inlet 14 is communicated with the flue gas inlet 132.

Further, it can be ensured that the flue gas generated in the combustion chamber 60 can enter the flue gas inlet 132 from the internal circulation flue gas inlet 14, and the situation that the flue gas cannot enter the flue gas inlet 132 can be avoided.

The inner circulation assembly 13 further includes a first guide plate 131 and a second guide plate 134, the first guide plate 131 is fixedly connected with the throat, a flue gas channel 136 is formed between the second guide plate 134 and the first guide plate 131, and the flue gas channel 136 is respectively communicated with the flue gas inlet 132 and the first outlet 135.

Further, the diameter of the cross section of the first guide plate 131 along the flow direction of the combustion air is gradually reduced, and the diameter of the cross section of the flue gas channel 136 along the flow direction of the internal circulation flue gas is gradually reduced, so that the flow rates of the combustion air and the internal circulation flue gas are increased, that is, the flow rate at the first outlet 135 is maximized, and the mixing degree of the combustion air and the internal circulation flue gas is optimal; it will be understood that the flue gas channel 136 may also be tapered (i.e., the diameter of the cross-section increases in the direction of the flow of the internally circulated flue gas), and the diameter of the cross-section of the flue gas channel 136 is not limited by the present invention, but preferably decreases.

Wherein, a flame nozzle 61 is fixedly installed at one side of the fuel port 15 inside the combustion chamber 60, and the flame nozzle 61 is fixedly connected with the furnace 10.

The air inlet pipes 12 are fixedly connected to two sides of the fuel inlet pipe 11 inside the hearth 10, the fuel inlet pipe 11 is internally provided with a fuel channel 17, and one end of the fuel inlet pipe 11 is fixedly connected with a fuel nozzle 18.

Further, the fuel inlet pipe 11 may be supplied with fuel by a slurry supply pump.

Further, a fuel nozzle 18 at one end of the fuel inlet pipe 11 is opposed to the fuel port 15.

As described in the above embodiments, the fuel required for combustion is injected into the combustion chamber 60 from the fuel channel 17 in the fuel inlet pipe 11 through the fuel nozzle 18, the combustion air required for combustion is injected into the combustion chamber 60 through the throat and the inner circulation assembly 13, when the combustion air flows through the inner circulation assembly 13, the flow area of the combustion air is gradually reduced, the flow rate of the combustion air is gradually increased, that is, the dynamic pressure is increased, the static pressure is reduced, the flow rate of the combustion air is increased to the maximum when the combustion air flows to the first outlet 135, the first outlet 135 is at a negative pressure relative to the flue gas inlet 132, the combustion air at a high flow rate sucks and rolls the external high-temperature flue gas, the high-temperature flue gas passes through the flue gas inlet 132, the flue gas channel 136 and the first outlet 135 of the inner circulation assembly 13 and then mixes with the combustion air flowing out from the throat to form the air-flue gas mixture with a low oxygen content, and the fuel injected into the combustion chamber 60 from the fuel inlet pipe 11 is combusted with a low oxygen content, the combination probability of oxygen and nitrogen in the fuel combustion process is reduced, so that the generation of thermal NOx is reduced, the combination probability of oxygen and fuel type compounds is reduced, the generation of fuel type NOx is reduced, and the emission of NOx after fuel combustion is greatly reduced.

Example 2:

referring to fig. 1, fig. 3, fig. 4 and fig. 6, the present invention provides a technical solution: a mixed combustion discharging device of a water-coal slurry boiler is characterized in that a burner head 40 comprises an outer sleeve 41 and a main fuel pipe 42, the outer sleeve 41 is sleeved outside the main fuel pipe 42, a plurality of rows of primary fuel holes 48 are axially arranged in the main fuel pipe 42, a combustion air hole 45 corresponding to each primary fuel hole 48 is arranged on the surface of the outer wall of the outer sleeve 41, an injection mechanism 49 is fixedly installed in each primary fuel hole 48, the injection mechanism 49 can be a fuel rod, the fuel rod is used for conveying fuel in the main fuel pipe 42 to the corresponding combustion air hole 45 so that the fuel and combustion air can be mixed in the combustion air hole 45, and the injection mechanism 49 extends into the combustion air hole 45 so that the fuel 44 and the combustion air 43 are mixed in the combustion air hole 45 to form a plurality of distributed flames at the combustion air hole 45.

Further, the length of the combustion-supporting air hole 45 is designed according to requirements, so that the mixing length of the combustion-supporting air and the fuel in the combustion-supporting air hole 45 can be prolonged, and the uniform mixing of the combustion-supporting air and the fuel is realized.

Further, one primary fuel hole 48, the corresponding injection mechanism 49, and the corresponding combustion air hole 45 form one micro channel.

Further, the micro-channels are uniformly arranged on the burner head 2 in a plurality of rows in a ring shape, the combustion air 4 and the fuel 3 are mixed through each micro-channel to form a flame, and the plurality of micro-channels are combusted to form a plurality of strands of distributed flames, so that a plurality of uniform distributed flames are formed at the outlet of the micro-channels.

One end of the main fuel pipe 42 extends to the outside of the outer sleeve 41 and is fixedly connected with a main fuel pipe end 46, the outer wall surface of the main fuel pipe end 46 is provided with a secondary fuel hole 461, the inside of the main fuel pipe 42 is provided with fuel 44, and the inside of the outer sleeve 41 is provided with combustion air 43.

Wherein, the end of the main fuel pipe 42 is provided with a deflector 47 for guiding the flow of the combustion-supporting air.

Further, a deflector 47 for guiding the flow of the combustion air is provided at an end of the main fuel pipe 42, so that the combustion air is mixed with the fuel through the deflector 47 to form the on-duty flame.

By combining the above embodiments, the characteristics of 'ultra-low emission, compact flame, high anti-backfire/flame holding performance' and the like of the microchannel distributed flame technology are fully utilized, the ultra-low emission of NOx is realized, the defects of the premixed combustion technology can be overcome, the potential safety hazards such as backfire and flame holding caused by high flame propagation speed can be prevented, and the ultra-low nitrogen emission standard which cannot be realized by staged combustion can also be solved.

In the several embodiments provided in the present invention, it should be understood that the disclosed apparatus may be implemented in other ways. The welding or screwing or winding of the parts to be welded or screwed together as shown or discussed can be assisted by means of devices such as welding torches, screwing with wrenches, etc., and the parts of the device can be made of various materials, such as metal materials, for example, aluminum alloys, steel and copper, by casting or by mechanical stamping.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. The mixed combustion discharging device of the water coal slurry boiler comprises:

the fuel inlet pipe (11) is fixedly installed in the hearth (10) close to the axis, a throat is arranged in the hearth (10), an inner circulation component (13) is fixedly installed in the hearth (10) at one end of the throat, the inner circulation component (13) comprises a flue gas inlet (132), a second outlet (133) and a first outlet (135), the first outlet (135) is located at one end of the throat, the second outlet (133) is opposite to the combustion chamber (60), and the flue gas inlet (132) is located on the outer sides of the second outlet (133) and the first outlet (135) and opposite to the combustion chamber (60);

a fan (20);

a burner head (40);

a combustion chamber (60);

the fan (20) is fixedly installed at the bottom end of the hearth (10), the combustion chamber (60) is fixedly connected to one end of the hearth (10), and the burner head (40) is fixedly connected to one end of the combustion chamber (60).

2. The mixed combustion exhaust apparatus of a water-coal slurry boiler as claimed in claim 1, wherein: further comprising:

a mounting plate (30);

the mounting plate (30) is fixedly mounted outside the hearth (10), and four corners of the outer wall of the mounting plate (30) are provided with screw holes.

3. The mixed combustion exhaust apparatus of a water-coal slurry boiler as claimed in claim 1, wherein: further comprising:

a base (50);

wherein, the base (50) is fixedly arranged on the bottom end surface of the hearth (10).

4. The hybrid combustion exhaust apparatus of a water-coal-slurry boiler as claimed in claim 1, wherein: the burner head (40) comprises an outer sleeve (41) and a main fuel pipe (42), the outer sleeve (41) is sleeved outside the main fuel pipe (42), multiple rows of primary fuel holes (48) are axially arranged in the main fuel pipe (42), combustion-supporting air holes (45) corresponding to each primary fuel hole (48) are arranged on the surface of the outer wall of the outer sleeve (41), an injection mechanism (49) is fixedly installed in each primary fuel hole (48), and the injection mechanism (49) extends into the combustion-supporting air holes (45).

5. The hybrid combustion exhaust apparatus of a water-coal-slurry boiler as claimed in claim 1, wherein: the surface of one end, close to the combustion chamber (60), of the hearth (10) is provided with an internal circulation flue gas inlet (14) and a fuel port (15), the internal circulation flue gas inlet (14) is located on two sides of the fuel port (15), and the internal circulation flue gas inlet (14) is communicated with the flue gas inlet (132).

6. The mixed combustion exhaust apparatus of a water-coal slurry boiler as claimed in claim 1, wherein: the inner circulation assembly (13) further comprises a first guide plate (131) and a second guide plate (134), the first guide plate (131) is fixedly connected with the throat, a flue gas channel (136) is formed between the second guide plate (134) and the first guide plate (131), and the flue gas channel (136) is respectively communicated with the flue gas inlet (132) and the first outlet (135).

7. The hybrid combustion exhaust apparatus of a water-coal-slurry boiler as claimed in claim 1, wherein: the combustion chamber (60) is internally provided with a flame nozzle (61) at one side of the fuel port (15), and the flame nozzle (61) is fixedly connected with the hearth (10).

8. The mixed combustion exhaust apparatus of a water-coal slurry boiler as claimed in claim 4, wherein: one end of the main fuel pipe (42) extends to the outside of the outer sleeve (41) and is fixedly connected with a main fuel pipe end (46), a secondary fuel hole (461) is formed in the outer wall surface of the main fuel pipe end (46), fuel (44) is arranged inside the main fuel pipe (42), and combustion-supporting air (43) is arranged inside the outer sleeve (41).

9. The mixed combustion exhaust apparatus of a water-coal slurry boiler as claimed in claim 4, wherein: and a flow guide disc (47) for guiding the circulation of combustion-supporting air is arranged at the end part of the main fuel pipe (42).

10. The mixed combustion exhaust apparatus of a water-coal slurry boiler as claimed in claim 1, wherein: the fuel inlet pipe is characterized in that the fuel inlet pipe (11) is fixedly connected with air inlet pipes (12) at two sides of the fuel inlet pipe (11) inside the hearth (10), a fuel channel (17) is arranged inside the fuel inlet pipe (11), and one end of the fuel inlet pipe (11) is fixedly connected with a fuel nozzle (18).