A combustor capable of burning ammonia in a large proportion

Abstract

The application provides a combustor capable of burning ammonia in a large proportion, and relates to the field of combustors.The combustor comprises a center gas gun, an ammonia gas gun, a center air duct, an inner secondary air duct, an outer secondary air duct and a combustor nozzle.The center air duct is located inside the inner secondary air duct, the outlet end of the inner secondary air duct is connected with the inlet end of the combustor nozzle, the inner secondary air duct and the combustor nozzle are located inside the outer secondary air duct, the center gas gun is located inside the center air duct, and the ammonia gas gun is located inside the inner secondary air duct.The combustor can realize mixed combustion of ammonia and high-calorific-value combustible gas, the ammonia mixing-burning proportion can reach 70%-80%, the combustor can burn ammonia in a large proportion, long-term stable combustion of the combustor is realized, carbon emission is reduced, and the purposes of complete combustion and reduction of nitrogen oxide emission are realized by adjusting the ammonia mixing proportion and the combustion-supporting secondary air distribution.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of burners, and particularly relates to a burner capable of burning ammonia gas in a large proportion. BACKGROUND

[0002] Ammonia as a carbon-free fuel is attracting more and more attention. The feasibility of carbon emission reduction through ammonia combustion has been verified by relevant research institutions. However, there are also problems such as high ignition temperature of ammonia gas, poor combustion characteristics, high NOx emission, etc. SUMMARY

[0003] The present application aims to solve the problems existing in the utilization of ammonia as a fuel, and proposes an effective solution to enable large-scale utilization of ammonia as a carbon-free fuel as soon as possible, while avoiding technical risks such as uncontrollable nitrogen oxides.

[0004] In order to solve the above technical problems, the present application provides a burner capable of burning ammonia gas in a large proportion, which comprises a center gas gun, an ammonia gas gun, a center air duct, an inner secondary air duct, an outer secondary air duct and a burner nozzle, the center air duct is located inside the inner secondary air duct, the outlet end of the inner secondary air duct is connected with the inlet end of the burner nozzle, the inner secondary air duct and the burner nozzle are located inside the outer secondary air duct, the center gas gun is located inside the center air duct, and the ammonia gas gun is located inside the inner secondary air duct.

[0005] The fuel in the center gas gun is a high-calorific-value stable-burning gas, which refers to an easy-to-burn gas with high heat generation during combustion, such as natural gas, etc., and generally refers to a gas with a heat generation higher than 3600 Kcal / Nm 3 The combustion-supporting air provided in the center air duct, the inner secondary air duct and the outer secondary air duct is air. The burner nozzle is a cavity, which provides a mixing combustion space for the fuel sprayed from the center gas gun and the ammonia gas sprayed from the ammonia gas gun, and the air provided from the center air duct and the inner secondary air duct.

[0006] Further, one side of the center air duct is in communication with a center air supply channel, a first air volume adjusting baffle is arranged in the center air supply channel, a swirl vane is arranged inside the center air duct, and the outlet end of the center air duct extends to the inside of the burner nozzle.

[0007] The swirl vane made of a steel plate is arranged obliquely in the center air duct, and when the air flows along the direction of the swirl vane, the air forms a rotating flow state. The swirl vane is welded and fixed with the center gas gun, and the nozzle end of the center gas gun protrudes out of the center air duct or is flush with the outlet end of the center air duct.

[0008] Further, one side of the inner secondary air duct is communicated with an inner secondary air supply channel, a second air volume adjusting baffle is arranged in the inner secondary air supply channel, and the inner secondary air duct is communicated with the burner nozzle.

[0009] Further, one side of the outer secondary air duct is communicated with an outer secondary air supply channel, a third air volume adjusting baffle is arranged in the outer secondary air supply channel, and the outlet end of the outer secondary air duct extends to the outside of the outlet end of the burner nozzle.

[0010] The first air volume adjusting baffle, the second air volume adjusting baffle and the third air volume adjusting baffle play a role in adjusting the air volume, and the air volume is changed by rotating the shaft to change the area of the air supply channel.

[0011] Further, one end of the ammonia gas gun is connected with an ammonia gas collecting ring, and the other end extends to the inside of the burner nozzle.

[0012] Further, the number of the ammonia gas guns is 3-20, and the nozzle end of each ammonia gas gun is in a bend structure, and the bend angle α of the nozzle end of each ammonia gas gun is-30°-+30°.

[0013] The nozzle end of the ammonia gas gun is designed in a bend structure, which can better mix the ammonia gas sprayed by the ammonia gas gun with the flame formed by the combustion of the fuel gas sprayed by the central fuel gas gun and the combustion-supporting air provided by the central air duct, and can better uniformly mix the ammonia gas with the combustion-supporting air provided by the inner secondary air duct, thereby facilitating the combustion and complete combustion of the ammonia gas.

[0014] Further, the inner wall of the burner nozzle is coated with a refractory insulation material, and a wall temperature thermocouple is arranged between the refractory insulation material and the inner wall of the burner nozzle.

[0015] Further, the central air duct, the inner secondary air duct, the outer secondary air duct and the burner nozzle are all in a hollow cylindrical structure, and the central axes coincide.

[0016] Further, the length-diameter ratio of the burner nozzle is in the range of 0.3-1, thereby meeting the mixing and combustion requirements. If the length of the burner nozzle is too short, it is not conducive to complete combustion, and if the length of the burner nozzle is too long, it is not conducive to reducing nitrogen oxides.

[0017] Further, the air volume in the central air duct accounts for 20%-30% of the total air volume of the burner, and the air volume in the outer secondary air duct accounts for 20%-40% of the total air volume of the burner.

[0018] The central air duct mainly provides air for the combustion of the fuel sprayed by the central fuel gas gun, the inner secondary air duct mainly controls the combustion intensity of the ammonia gas and the central fuel gas and the temperature of the burner nozzle, and the outer secondary air duct mainly meets the oxygen requirement for the combustion of the remaining gas, and the outer secondary air duct is used to grade the air supply, thereby achieving the purpose of controlling the emission of nitrogen oxides.

[0019] Further, the proportion of the amount of gas in the center gas gun to the total amount of gas is 20%-30%, and the proportion of the amount of ammonia gas in the ammonia gas gun to the total amount of gas is 70%-80% (thermal load proportion).

[0020] When the burner is running, the center gas gun is first ignited and rises to the maximum load of the center gas gun, the inner wall area temperature of the burner nozzle is heated and stored by burning through the center gas gun, and the inner wall area temperature of the burner nozzle is measured by a wall temperature thermocouple. When the temperature of the wall temperature thermocouple reaches 1000 DEG C or above, the ammonia gas gun starts to gradually mix and run, ammonia gas is injected into the burner nozzle for mixed combustion, and the ammonia gas mixing ratio and the combustion air distribution are adjusted to keep the inner wall temperature of the burner nozzle between 1000 DEG C and 1300 DEG C, so as to realize complete combustion and reduce the emission of nitrogen oxides.

[0021] Beneficial effects:

[0022] (1) The present application provides a burner capable of mixing ammonia gas in a large proportion, which comprises a center gas gun, an ammonia gas gun, a center air duct, an inner secondary air duct, an outer secondary air duct and a burner nozzle. The center air duct is located inside the inner secondary air duct, the outlet end of the inner secondary air duct is connected to the inlet end of the burner nozzle, the inner secondary air duct and the burner nozzle are located inside the outer secondary air duct, the center gas gun is located inside the center air duct, and the ammonia gas gun is located inside the inner secondary air duct. The center air duct mainly supplies air for the combustion of the fuel sprayed by the center gas gun, the inner secondary air duct supplies air for the ammonia gas gun and the center gas gun, mainly controls the combustion intensity of ammonia gas and the center gas, and controls the temperature of the burner nozzle, and the outer secondary air duct mainly meets the oxygen demand of the remaining gas combustion, provides the required combustion air for the gas combustion in the later stage, and realizes the control of nitrogen oxide emission through the staged air distribution of the outer secondary air duct.

[0023] (2) The present application can realize the mixed combustion of ammonia gas and high-calorific-value flammable gas, the ammonia gas mixing ratio can reach 70%-80% (thermal load proportion), the burner can mix ammonia gas combustion in a large proportion, realizes long-term stable combustion of the burner, and reduces carbon emission.

[0024] The concept, specific structure and technical effects of the present application will be further described below with reference to the accompanying drawings, so as to fully understand the purpose, features and effects of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is a structural schematic view of a burner capable of mixing ammonia gas in a large proportion;

[0026] Reference signs:

[0027] 1. Central gas lance; 2. Ammonia lance; 3. Ammonia gas collecting ring; 4. Inner secondary air duct; 5. Outer secondary air duct; 6. Central air duct; 7. Second air volume regulating baffle; 8. Third air volume regulating baffle; 9. First air volume regulating baffle; 10. Swirl blades; 11. Refractory insulation material; 12. Burner nozzle; 13. Wall temperature thermocouple. Detailed Implementation

[0028] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0029] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, the thickness of some components has been appropriately exaggerated in the drawings.

[0030] Embodiments:

[0031] like Figure 1 As shown, in a preferred embodiment, the present invention provides a burner capable of co-firing ammonia in a large proportion, comprising a central gas gun 1, an ammonia gun 2, a central air duct 6, an inner secondary air duct 4, an outer secondary air duct 5, and a burner nozzle 12. The central air duct 6 is located inside the inner secondary air duct 4, and the outlet end of the inner secondary air duct 4 is connected to the inlet end of the burner nozzle 12. The inner secondary air duct 4 and the burner nozzle 12 are located inside the outer secondary air duct 5. The central gas gun 1 is located inside the central air duct 6, and the ammonia gun 2 is located inside the inner secondary air duct 4. The left side of the central air duct 6 is sealed, and the central gas gun 1 passes through the left side wall of the central air duct 6 and enters the interior of the central air duct 6.

[0032] The fuel in the central gas gun 1 is a high-calorific-value, easily stable combustible gas, referring to a gas that produces high heat when burned, such as natural gas, generally with a calorific value higher than 600 kcal / Nm³. 3 The combustion air supplied in the central air duct 6, the inner secondary air duct 4, and the outer secondary air duct 5 is all air. The burner nozzle 12 is a cavity that provides a mixing and combustion space for the fuel injected from the central gas gun 1 and the ammonia injected from the ammonia gun 2, along with the combustion air supplied from the central air duct 6 and the inner secondary air duct 4.

[0033] The left side of the central air duct 6 is communicated with the central air supply channel, the first air volume adjusting baffle 9 is arranged in the central air supply channel, the outlet end of the central air duct 6 extends to the inside of the burner nozzle 12, the swirl vane 10 made of steel plate is arranged at a position close to the outlet end in the central air duct 6 and is arranged obliquely, the wind flows along the direction of the swirl vane 10 when the wind passes through, so that the wind forms a rotating flow state, the swirl vane 10 is welded and fixed with the central gas gun 1, and the nozzle end of the central gas gun 1 extends out of the central air duct 6 or is flush with the outlet end of the central air duct 6.

[0034] The left side of the inner secondary air duct 4 is communicated with the inner secondary air supply channel, the second air volume adjusting baffle 7 is arranged in the inner secondary air supply channel, and the inner secondary air duct 4 is communicated with the burner nozzle 12.

[0035] The left side of the outer secondary air duct 5 is communicated with the outer secondary air supply channel, the third air volume adjusting baffle 8 is arranged in the outer secondary air supply channel, the outlet end of the outer secondary air duct 5 extends to the outside of the outlet end of the burner nozzle 12 and is mixed with the flue gas of the burner nozzle.

[0036] The central air supply channel, the inner secondary air supply channel and the outer secondary air supply channel are all hollow cylindrical structures, which can provide uniform circumferential air supply for the burner.

[0037] The first air volume adjusting baffle 9, the second air volume adjusting baffle 7 and the third air volume adjusting baffle 8 play a role in adjusting the air volume, the air volume is changed by rotating the shaft to change the area of the air supply channel, and all are prior art.

[0038] The inner wall of the burner nozzle 12 is coated with the refractory insulation material 11, 2 wall temperature thermocouples 13 are uniformly arranged between the refractory insulation material 11 and the inner wall of the burner nozzle 12 in the circumferential direction, and are used for monitoring the temperature in the burner nozzle 12.

[0039] The central air duct 6, the inner secondary air duct 4, the outer secondary air duct 5 and the burner nozzle 12 are all hollow cylindrical structures, and the central axes coincide.

[0040] One end of the ammonia gas gun 2 is connected with the ammonia gas collecting ring 3, and the other end extends to the inside of the burner nozzle 12, so that the ammonia gas is sprayed into the burner nozzle 12.

[0041] The number of the ammonia gas gun 2 is related to the burner power and the blending ratio, in the embodiment, the number of the ammonia gas gun 2 is 15, the nozzle end of each ammonia gas gun 2 is a bend structure, the bend angle α of the nozzle end of each ammonia gas gun 2 is 25°, the maximum load of the central gas gun 1 and the ammonia gas gun 2 is 10MW and 30MW respectively, the ammonia gas blending heat value ratio is 75%, and the proportion of the natural gas in the central gas gun 1 is 25%.

[0042] The air volume in the central air duct 6 accounts for 30% of the total air volume of the burner, the air volume in the outer secondary air duct 5 accounts for 30% of the total air volume of the burner, and the air volume in the inner secondary air duct 4 accounts for 40% of the total air volume of the burner. The length-diameter ratio of the burner nozzle 12 is 0.5. The final carbon emission is about 1000 m 3 / h, and the nitrogen oxide emission is 50-100 mg / Nm 3 , and the same emission level as pure high-calorific-value flammable gas is achieved.

[0043] The nozzle end of the ammonia gas gun 2 is designed as an elbow structure, which can better mix the ammonia gas sprayed by the ammonia gas gun 2 with the flame formed by the combustion of the fuel gas sprayed by the central fuel gas gun 1 and the combustion-supporting air provided by the central air duct 6, and better mix the ammonia gas with the combustion-supporting air provided by the inner secondary air duct 4, which is beneficial to the combustion and burnout of the ammonia gas.

[0044] In the burner provided by the application, the central air duct 6 mainly provides air for the combustion of the fuel gas sprayed by the central fuel gas gun 1, the inner secondary air duct 4 provides air for the ammonia gas gun 2 and the central fuel gas gun 1, mainly controls the combustion intensity of the ammonia gas and the central fuel gas, and controls the temperature of the burner nozzle 12, and the outer secondary air duct 5 mainly meets the oxygen demand of the combustion of the remaining gas, provides the required burnout air volume for the combustion of the fuel gas in the later stage, and realizes the control of nitrogen oxide emission through the staged air distribution of the outer secondary air duct 5.

[0045] The application can realize the mixed combustion of ammonia gas and high-calorific-value flammable gas, the ammonia gas blending ratio can reach 70%-80%, and the low-carbon combustion of the burner is realized. When the burner is running, the central fuel gas gun 1 is first ignited, and is raised to the maximum load of the central fuel gas gun 1, the wall surface of the refractory heat preservation material 11 of the burner nozzle 12 is heated and stored by the combustion of the central fuel gas gun 1, the inner wall area temperature of the burner nozzle 12 is measured by the wall temperature thermocouple 13, when the temperature of the wall temperature thermocouple 13 reaches above 1000 DEG C, the ammonia gas gun 2 starts to gradually blend and run, ammonia gas is sprayed into the burner nozzle 12 for blending combustion, and the ammonia gas blending ratio and the combustion-supporting secondary air distribution are adjusted, so that the inner wall temperature of the burner nozzle 12 is kept between 1000 DEG C and 1300 DEG C, thereby realizing the purpose of burnout and reducing nitrogen oxide emission.

[0046] Finally, it should be noted that the application is not limited to the above-mentioned embodiments, any equivalent structure or equivalent flow conversion made by referring to the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the protection scope of the application.

Claims

1. A combustor capable of large-scale ammonia gas co-firing, characterized by, It comprises a center gas gun (1), an ammonia gun (2), a center air duct (6), an inner secondary air duct (4), an outer secondary air duct (5) and a burner nozzle (12), the center air duct (6) is located inside the inner secondary air duct (4), the outlet end of the inner secondary air duct (4) is connected with the inlet end of the burner nozzle (12), the inner secondary air duct (4) and the burner nozzle (12) are located inside the outer secondary air duct (5), the center gas gun (1) is located inside the center air duct (6), and the ammonia gun (2) is located inside the inner secondary air duct (4). The center air duct (6), the inner secondary air duct (4), the outer secondary air duct (5) and the burner nozzle (12) are all hollow cylindrical structures with coincident central axes. The number of the ammonia gun (2) is 3-20, the nozzle end of the ammonia gun (2) is a bend structure, and the bend angle α of the nozzle end of each ammonia gun (2) is -30°-+30°. The inner wall of the burner nozzle (12) is coated with a refractory insulation material (11), and a wall temperature thermocouple (13) is arranged between the refractory insulation material (11) and the inner wall of the burner nozzle (12).

2. The ammonia gas scalable burner of claim 1, wherein, One side of the center air duct (6) is communicated with a center air supply channel, a first air volume adjusting baffle (9) is arranged in the center air supply channel, and a rotating flow vane (10) is arranged inside the center air duct (6).

3. The ammonia gas scalable burner of claim 1, wherein, One side of the inner secondary air duct (4) is communicated with an inner secondary air supply channel, a second air volume adjusting baffle (7) is arranged in the inner secondary air supply channel, and the inner secondary air duct (4) is communicated with the burner nozzle (12).

4. The ammonia gas scalable burner of claim 1, wherein, One side of the outer secondary air duct (5) is communicated with an outer secondary air supply channel, a third air volume adjusting baffle (8) is arranged in the outer secondary air supply channel, and the outlet end of the outer secondary air duct (5) extends to the outside of the outlet end of the burner nozzle (12).

5. The ammonia gas scalable burner of claim 1, wherein, One end of the ammonia gun (2) is connected with an ammonia gas collecting ring (3), and the other end extends to the inside of the burner nozzle (12).

6. The ammonia gas scalable burner of claim 1, wherein, The length-diameter ratio of the burner nozzle (12) ranges from 0.3 to 1.

7. The ammonia gas scalable burner of claim 1, wherein, The air volume in the center air duct (6) accounts for 20%-30% of the total air volume of the burner, and the air volume in the outer secondary air duct (5) accounts for 20%-40% of the total air volume of the burner.

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