A low calorific value gas low nitrogen swirl burner with adjustable flame shape

Abstract

The invention discloses a low-calorific-value gas low-nitrogen swirl burner with an adjustable flame shape, comprising an adjustable connecting rod structure and an ignition gun assembly, a central fuel cylinder, a central combustion-supporting air cylinder, an outer fuel cylinder and a burner shell which are arranged in stages from the inside to the outside, an annular inner swirl wind area is formed between the central fuel cylinder and the central combustion-supporting air cylinder, an annular swirl gas area is formed between the central combustion-supporting air cylinder and the outer fuel cylinder, an annular outer swirl wind area is formed between the outer fuel cylinder and the burner shell, a central fuel inlet is provided on the central fuel cylinder, and a central combustion-supporting air inlet is provided on the central combustion-supporting air cylinder. The burner can meet emission requirements and boiler performance requirements.

Description

Technical Field

[0001] The invention belongs to the technical field of gas low-nitrogen clean combustion, and relates to a low-calorific-value gas low-nitrogen swirl burner with adjustable flame shape. Background Art

[0002] In recent years, as energy demand has skyrocketed year by year and the problem of atmospheric pollution has become increasingly prominent, society has gradually begun to pay attention to the low calorific value gases that were previously incinerated at will.

[0003] Low calorific value gas fuels are mainly produced in the process of chemical, metallurgical and other industries. The main types include blast furnace gas, formaldehyde gas, COREX gas and straw gasification gas. Unlike natural gas, the main components of low calorific value gas fuels are often inert gases, such as nitrogen, carbon dioxide or water vapor. Among them, the volume percentage concentration of combustible components (such as carbon monoxide or hydrogen) is usually only about 25%, and the calorific value is very low. Generally, a small part enters industrial kilns for combustion, and the rest is directly ignited as tail gas and discharged into the atmosphere by torch combustion. The concentration of nitrogen oxides produced by both methods is relatively high.

[0004] As a key equipment for making full use of low calorific value gas fuel, most of the research on low calorific value gas burners in China focuses on improving the performance of burners, and pays less attention to the control of atmospheric pollutants. With the introduction of the latest atmospheric pollutant emission standards across the country, traditional low calorific value gas burners alone can no longer meet the latest emission requirements, and the transformation of existing furnace types will inevitably involve the problem of matching the size of the new burner with the old furnace. Therefore, it is necessary to develop a new type of low calorific value gas low nitrogen burner to meet the latest emission requirements and boiler performance requirements at the same time. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a low calorific value gas low nitrogen swirl burner with adjustable flame shape, which can meet emission requirements and boiler performance requirements.

[0006] To achieve the above-mentioned purpose, the low-calorific-value gas low-nitrogen swirl burner with adjustable flame shape described in the present invention comprises an adjustable connecting rod structure and an ignition gun assembly, a central fuel cylinder, a central combustion-supporting air cylinder, an outer fuel cylinder and a burner shell arranged step by step from the inside to the outside, an annular inner swirl wind area is formed between the central fuel cylinder and the central combustion-supporting air cylinder, an annular swirl gas area is formed between the central combustion-supporting air cylinder and the outer fuel cylinder, an annular outer swirl wind area is formed between the outer fuel cylinder and the burner shell, a central fuel inlet is provided on the central fuel cylinder, and a central combustion-supporting air inlet is provided on the central combustion-supporting air cylinder;

[0007] An annular swirl plate is arranged between the central fuel cylinder and the central combustion-supporting air cylinder, an angle-adjustable fuel swirl disk is arranged between the central combustion-supporting air cylinder and the outer fuel cylinder, and an angle-adjustable combustion-supporting air swirl disk is arranged between the outer fuel cylinder and the burner shell;

[0008] The burner shell is provided with a combustion-supporting air inlet, which is connected to the burner shell; the burner shell is provided with a low calorific value gas fuel inlet, which is connected to the central fuel cylinder and the outer fuel cylinder;

[0009] One end of the adjustable connecting rod structure is located outside the burner shell, and the other end of the adjustable connecting rod structure is connected to the angle-adjustable fuel swirl disk and the angle-adjustable combustion-supporting air swirl disk.

[0010] The rotation angle of the annular swirl plate is 15°-75°.

[0011] The adjustment range of the swirl blades in the angle-adjustable fuel swirl disk and the angle-adjustable combustion-supporting air swirl disk is 5°-175°.

[0012] The adjustable connecting rod structure includes a first movable annular guide rail, a second movable annular guide rail, a first movable connecting rod, a second movable connecting rod, a hollow connecting rod and a solid connecting rod, wherein one end of the hollow connecting rod is inserted into the burner casing and connected to the swirl blades in the angle-adjustable combustion-supporting air swirl disk; one end of the solid connecting rod axially passes through the hollow connecting rod and the outer fuel cylinder and is connected to the swirl blades in the angle-adjustable fuel swirl disk, one end of the first movable connecting rod is connected to the other end of the hollow connecting rod, the other end of the first movable connecting rod is connected to the first movable annular guide rail, one end of the second movable connecting rod is connected to the other end of the solid connecting rod, the other end of the second movable connecting rod is connected to the second movable annular guide rail, the first control handle is connected to the first movable annular guide rail, and the second control handle is connected to the second movable annular guide rail.

[0013] The first control handle and the second control handle are both provided with adjustment angle indicating devices.

[0014] The axis of the central fuel cylinder coincides with the axis of the ignition gun assembly, and a circular air distribution disk is arranged at the outlet of the ignition gun assembly.

[0015] Manual adjustment flanges are provided at the central fuel inlet and the central combustion air inlet.

[0016] The present invention has the following beneficial effects:

[0017] During the specific operation of the low-calorific-value gas low-nitrogen swirl burner with adjustable flame shape described in the present invention, the low-calorific-value gas fuel is ejected in two stages through the central fuel tube and the outer fuel tube, and the combustion-supporting air is ejected in two stages through the central combustion-supporting air tube and the burner shell into the furnace. Under the action of the swirl, it is violently mixed with the gas fuel and evenly burned, thereby reducing the peak temperature in the furnace and reducing the local high-temperature area, so as to reduce the generation of nitrogen oxides and meet the emission requirements. In addition, the low-calorific-value gas fuel is arranged between the inner swirl wind and the outer swirl wind, and it is not easy to cause fire extinguishing and other phenomena that endanger the safe and stable operation of the boiler. The angle of the swirl blades in the angle-adjustable fuel swirl disk and the angle-adjustable combustion-supporting air swirl disk are adjusted by the adjustable connecting rod structure to ensure that the flame shape of the burner is uniquely matched with different furnace types, ensure the optimal performance of the boiler, and meet the emission and boiler performance requirements.

[0018] Furthermore, a circular air distribution disk is provided at the outlet of the ignition gun assembly to enhance the flame stabilization capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic cross-sectional view of the structure of the present invention;

[0020] Figure 2 It is a schematic side view of the structure of the present invention;

[0021] Figure 3 It is a structural schematic diagram of the burner throat of the present invention;

[0022] Figure 4 It is a schematic diagram of the adjustable connecting rod structure 14 of the present invention.

[0023] Among them, 1 is the boiler connecting flange, 2 is the ignition gun assembly, 3 is the central fuel cylinder, 4 is the central combustion-supporting air cylinder, 5 is the outer fuel cylinder, 6 is the burner shell, 7 is the low calorific value gas fuel inlet, 8 is the combustion-supporting air inlet, 9 is the central fuel inlet, 10 is the central combustion-supporting air inlet, 11 is the annular swirl plate, 12 is the angle-adjustable fuel swirl disk, 13 is the angle-adjustable combustion-supporting air swirl disk, 14 is the adjustable connecting rod structure, 14-1 is the first movable annular guide rail, 14-2 is the second movable annular guide rail, 14-3 is the movable connecting rod, 14-4 is the hollow connecting rod, 14-5 is the solid connecting rod, 15 is the second control handle, 16 is the first control handle, 17 is the flame monitoring device, and 18 is the fire viewing mirror. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0025] refer to Figures 1 to 4The low calorific value gas low nitrogen swirl burner with adjustable flame shape described in the present invention comprises an adjustable connecting rod structure 14 and an ignition gun assembly 2, a central fuel cylinder 3, a central combustion-supporting air cylinder 4, an outer fuel cylinder 5 and a burner shell 6 which are arranged step by step from the inside to the outside. An annular inner swirl wind area is formed between the central fuel cylinder 3 and the central combustion-supporting air cylinder 4, an annular swirl gas area is formed between the central combustion-supporting air cylinder 4 and the outer fuel cylinder 5, and an annular outer swirl wind area is formed between the outer fuel cylinder 5 and the burner shell 6. A central fuel inlet 9 is provided on the central fuel cylinder 3, and a central combustion-supporting air inlet 10 is provided on the central combustion-supporting air cylinder 4. The central fuel cylinder 3 and the central combustion-supporting air cylinder 4 are provided with a central fuel inlet 9, and a central combustion-supporting air inlet 10 is provided on the central fuel cylinder 3 and the central combustion-supporting air cylinder 4. An annular swirl plate 11 is arranged between the central combustion air cylinder 4 and the outer fuel cylinder 5, an angle-adjustable fuel swirl disk 12 is arranged between the central combustion air cylinder 4 and the outer fuel cylinder 5, and an angle-adjustable combustion air swirl disk 13 is arranged between the outer fuel cylinder 5 and the burner casing 6; a combustion air inlet 8 is arranged on the burner casing 6, and the combustion air inlet 8 is connected to the burner casing 6; a low calorific value gas fuel inlet 7 is arranged on the burner casing 6, and the low calorific value gas fuel inlet 7 is connected to the central fuel cylinder 3 and the outer fuel cylinder 5; one end of the adjustable connecting rod structure 14 is located outside the burner casing 6, and the other end of the adjustable connecting rod structure 14 is connected to the angle-adjustable fuel swirl disk 12 and the angle-adjustable combustion air swirl disk 13.

[0026] The rotation angle of the annular swirl plate 11 is 15°-75°; the adjustment range of the swirl blades in the angle-adjustable fuel swirl disk 12 and the angle-adjustable combustion-supporting air swirl disk 13 is 5°-175°.

[0027] The adjustable connecting rod structure 14 includes a first movable annular guide rail 14-1, a second movable annular guide rail 14-2, a first movable connecting rod 14-3, a second movable connecting rod, a hollow connecting rod 14-4 and a solid connecting rod 14-5, wherein one end of the hollow connecting rod 14-4 is inserted into the burner housing 6 and connected to the swirl blades in the angle-adjustable combustion air swirl disk 13; one end of the solid connecting rod 14-5 axially passes through the hollow connecting rod 14-4 and the outer fuel cylinder 5 and connects to the swirl blades in the angle-adjustable fuel swirl disk 12. The plates are connected, one end of the first movable link 14-3 is connected to the other end of the hollow connecting rod 14-4, the other end of the first movable link 14-3 is connected to the first movable annular guide rail 14-1, one end of the second movable link is connected to the other end of the solid connecting rod 14-5, the other end of the second movable link is connected to the second movable annular guide rail 14-2, the first control handle 16 is connected to the first movable annular guide rail 14-1, and the second control handle 15 is connected to the second movable annular guide rail 14-2.

[0028] The first control handle 16 and the second control handle 15 are both provided with adjustment angle indicating devices; the axis of the central fuel cylinder 3 coincides with the axis of the ignition gun assembly 2, and a circular air distribution disk is provided at the outlet of the ignition gun assembly 2; the central fuel inlet 9 and the central combustion-supporting air inlet 10 are both provided with manual adjustment flanges.

[0029] A boiler connection flange 1 is arranged on the outer side of the burner housing 6. The ignition gun assembly 2 is filled with a high calorific value gas fuel, such as natural gas, for ignition. A circular air distribution plate is arranged at the outlet of the ignition gun assembly 2. The gas ejected from the ignition gun assembly 2 is ignited by a high-energy igniter, and the generated flame successfully ignites the low calorific value gas fuel in the center and then exits; the flame generated by the central gas spreads to the outer circle under the action of the central swirl wind, ignites the outer swirl gas-wind mixture, and finally establishes a complete combustion supported by layers;

[0030] During the operation of the burner, the angles of the swirl blades in the angle-adjustable fuel swirl disk 12 and the angle-adjustable combustion-supporting air swirl disk 13 are adjusted separately by pulling the first control handle 16 and the second control handle 15 simultaneously in the axial direction. Specifically, the actual swirl blade angle can be determined according to the adjustment angle indicating device; the ratio of the central gas fuel, the outer gas fuel and the combustion-supporting air is adjusted by manually adjusting the flange. By adjusting the angles of the swirl blades in the angle-adjustable fuel swirl disk 12 and the angle-adjustable combustion-supporting air swirl disk 13, the outer gas fuel and the combustion-supporting air enter the furnace at different swirl jet angles and mix with each other, thereby realizing online adjustment of the flame shape in the furnace. The flame shape, color and flame fullness in the furnace can be visually observed through the fire viewing hole behind the boiler furnace and the burner fire viewing mirror 18, and the combustion condition can be scientifically judged through the flue gas monitoring emission data, so as to achieve the best combustion state suitable for the current furnace type.

[0031] The present invention divides low calorific value gas fuel and combustion-supporting air into two levels, and delivers them into the furnace in a swirling flow to achieve a uniform mixing state. At the same time, by adjusting the amount of gas fuel and air volume at each level, high load regulation, furnace and fuel adaptability can be achieved to achieve the purpose of reducing nitrogen oxides to the greatest extent. In specific implementation, the present invention provides an economical and environmentally friendly transformation technology route for reducing the emission concentration of nitrogen oxides in low calorific value gas boilers. Without adding any denitrification device, the boiler nitrogen oxide emission concentration can be reduced to 50mg / m by simply replacing the burner. 3 (standard state, 3.5% O2) or less, thereby achieving safe and stable operation of the boiler while meeting the latest environmental protection standards.

Claims

1. A low calorific value gas low nitrogen swirl burner with adjustable flame shape, characterized in that: The invention comprises an adjustable connecting rod structure (14) and an ignition gun assembly (2), a central fuel cylinder (3), a central combustion-supporting air cylinder (4), an outer fuel cylinder (5) and a burner shell (6) which are arranged step by step from the inside to the outside. An annular inner swirl wind region is formed between the central fuel cylinder (3) and the central combustion-supporting air cylinder (4), an annular swirl air region is formed between the central combustion-supporting air cylinder (4) and the outer fuel cylinder (5), and an annular outer swirl wind region is formed between the outer fuel cylinder (5) and the burner shell (6). A central fuel inlet (9) is provided on the central fuel cylinder (3), and a central combustion-supporting air inlet (10) is provided on the central combustion-supporting air cylinder (4). An annular swirl plate (11) is arranged between the central fuel cylinder (3) and the central combustion-supporting air cylinder (4), an angle-adjustable fuel swirl disk (12) is arranged between the central combustion-supporting air cylinder (4) and the outer fuel cylinder (5), and an angle-adjustable combustion-supporting air swirl disk (13) is arranged between the outer fuel cylinder (5) and the burner casing (6); The burner shell (6) is provided with a combustion-supporting air inlet (8), which is in communication with the burner shell (6); the burner shell (6) is provided with a low-calorific value gas fuel inlet (7), which is in communication with the central fuel cylinder (3) and the outer fuel cylinder (5); One end of the adjustable connecting rod structure (14) is located outside the burner housing (6), and the other end of the adjustable connecting rod structure (14) is connected to the angle-adjustable fuel swirl disk (12) and the angle-adjustable combustion-supporting air swirl disk (13); The rotation angle of the annular swirl plate (11) is 15°-75°; The adjustable connecting rod structure (14) comprises a first movable annular guide rail (14-1), a second movable annular guide rail (14-2), a first movable connecting rod (14-3), a second movable connecting rod, a hollow connecting rod (14-4) and a solid connecting rod (14-5), wherein one end of the hollow connecting rod (14-4) is inserted into the burner casing (6) and connected to the swirl blades in the angle-adjustable combustion-supporting air swirl disk (13); one end of the solid connecting rod (14-5) passes through the hollow connecting rod (14-4) and the outer fuel cylinder (5) in the axial direction and is connected to the angle-adjustable fuel swirl disk (12). The swirl blades are connected, one end of the first movable link (14-3) is connected to the other end of the hollow connecting rod (14-4), the other end of the first movable link (14-3) is connected to the first movable annular guide rail (14-1), one end of the second movable link is connected to the other end of the solid connecting rod (14-5), the other end of the second movable link is connected to the second movable annular guide rail (14-2), a first control handle (16) is connected to the first movable annular guide rail (14-1), and a second control handle (15) is connected to the second movable annular guide rail (14-2); The first control handle (16) and the second control handle (15) are both provided with adjustment angle indicating devices.

2. The low calorific value gas low nitrogen swirl burner with adjustable flame shape according to claim 1 is characterized in that: The adjustment range of the swirl blades in the angle-adjustable fuel swirl disk (12) and the angle-adjustable combustion-supporting air swirl disk (13) is 5°-175°.

3. The low calorific value gas low nitrogen swirl burner with adjustable flame shape according to claim 1, characterized in that: The axis of the central fuel cylinder (3) coincides with the axis of the ignition gun assembly (2), and a circular air distribution disk is arranged at the outlet of the ignition gun assembly (2).

4. The low calorific value gas low nitrogen swirl burner with adjustable flame shape according to claim 1, characterized in that: Manual adjustment flanges are provided at the central fuel inlet (9) and the central combustion-supporting air inlet (10).

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