A double-helix water-cooled premixed burner with self-stabilizing combustion characteristics
Through the design of a double-helix water-cooled premixed burner, the use of electronic ignition and ignition grooves to quickly propagate the flame, combined with a stable combustion disk and cooling water to reduce the temperature, the problems of difficult ignition of the burner at high wind speeds and high NOx emissions are solved, and safe, low-cost low-NOx combustion is achieved.
Patent Information
- Application Number
- CN202211285265.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-10-20
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2042-10-20
AI Technical Summary
Existing burners have difficulty igniting premixed gas at high wind speeds, which easily leads to deflagration. In addition, the NOx emission concentration generated by combustion is high, making it difficult to meet strict emission requirements and increasing operating costs.
It adopts a double-helix water-cooled premix burner, uses electronic ignition to achieve central gas ignition and diffusion combustion, combines with the ignition groove to quickly spread the flame, and is equipped with a stable combustion plate and a stable combustion device to ensure ignition stability. It also uses cooling water to lower the combustion temperature and reduce NOx emissions.
It achieves stable ignition at low wind speeds, avoids the risk of deflagration, lowers combustion temperature, reduces NOx emissions, meets strict emission standards, and reduces operating costs.
Smart Images
Figure CN115638410B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of burners, and in particular to a double-helix water-cooled premixed burner with self-stable combustion characteristics. Background Art
[0002] A burner is a thermal device that converts the chemical energy in fuel into heat through combustion. Conventional gas or liquid premix combustion involves premixing the fuel and air before feeding it into the burner for combustion. However, due to the high power of burners, most combustion equipment requires a blower. This is susceptible to the blower's high wind speed, making it difficult for the fuel to ignite. Frequent ignitions can easily lead to deflagration and safety accidents.
[0003] Gas burners mainly produce thermal nitrogen oxides. The main factors affecting the generation of thermal nitrogen oxides are temperature, residence time and the amount of oxygen supplied for combustion. In the absence of any reducing atmosphere and appropriate oxygen supply, the higher the temperature and the longer the residence time, the higher the outlet emission concentration of NOx.
[0004] As emission requirements in various provinces and cities in China become increasingly stringent, the minimum nitrogen oxide emission concentration of gas burners is 30mg / m 3 The use of technologies such as flue gas recirculation requires additional equipment such as fans, which requires a significant increase in operating costs. Summary of the Invention
[0005] In order to overcome the above technical problems, the purpose of the present invention is to provide a double-helix water-cooled premixed burner with self-stabilizing combustion characteristics, which uses electronic ignition to ignite the central gas for diffusion combustion, and realizes rapid flame propagation through the ignition groove. The flame diffusion quickly ignites the premixed gas, solves the problem that the premixed gas cannot be ignited in time due to excessive wind speed inside the combustion device, and eliminates the potential fire extinguishing and explosion hazards at low load; at the same time, cooling water is used to achieve rapid cooling of the burner surface, reduce the temperature of the high-temperature area, and quickly achieve low-temperature and low-NOx combustion.
[0006] In order to achieve the above object, the technical solution adopted by the present invention is:
[0007] A double-helix water-cooled premix burner with self-stabilizing combustion characteristics, comprising a double-helix water-cooled coil, a combustion stabilizing plate, an ignition gun, a combustion stabilizing device, an ignition tank, an isobaric air supply mixing chamber, an "S"-shaped connecting pipe and a fixed-distance screw;
[0008] The water inlet pipe and the water outlet pipe form a double-helix water-cooling coil, and the water inlet pipe and the water outlet pipe alternately spiral up along the central axis to form a spiral pipe and a circular stepped ladder-shaped flame combustion contact surface. The alternating spiral up makes the water inlet pipe and the water outlet pipe adjacent to each other. The water inlet pipe and the water outlet pipe are fixed with fixed-distance screws. The outermost spiral pipe is connected to the isobaric air supply mixing chamber, and the innermost spiral pipe is connected to the water inlet pipe and the water outlet pipe by an "S"-shaped connecting pipe; a stabilizing disk is arranged on the plane of the innermost spiral pipe along the central axis, and an ignition gun and a stabilizer are provided above the outlet of the stabilizing disk along the direction of airflow; the combustion contact surface of the double-helix water-cooling coil is provided with an ignition groove, and the airflow direction is upward as it goes further back.
[0009] The cross-section of the double-helix water-cooling coil along the central axis is a "runway" type pressure-bearing center hole structure, with hemispherical fronts at both ends, flat sides of the spiral coil, and a circular water-cooling pipe in the center; and anti-backfire channels are formed on the sides of adjacent spiral coils.
[0010] The combustion side of the double-helix water-cooled coil is equipped with ignition grooves, which quickly propagate the central flame to the outermost spiral tube, achieving rapid combustion of the premixed gas. The combustion side is the surface on the coil where the gas ejected from the coil burns.
[0011] The flame stabilizing disk is placed on the center plane of the innermost spiral tube (plane 2), and an air nozzle is provided on the flame stabilizing disk; the ignition gun and the flame stabilizing device are placed in two adjacent areas of the "S"-shaped connecting pipe, and the plane (plane 1) where the gas nozzles of the ignition gun and the flame stabilizing device are located is arranged above the flame stabilizing disk.
[0012] The isobaric air supply mixing chamber inlet includes flow equalizing plate 1 and flow equalizing plate 2, and the isobaric air supply mixing chamber outlet has a double spiral water cooling coil to form an isobaric circular step shape, and an ignition gun pipe is provided in the center.
[0013] The cross section of the ignition groove is semicircular, and the ignition groove and the fixed distance screw are arranged at an interval of 60 degrees, and adjacent ignition grooves and fixed distance screws are arranged at 120 degrees.
[0014] The distance screw can be set at any position, and the distance screw is used to maintain a distance from the position of the ignition groove.
[0015] The double-helix water cooling coil comprises a water inlet pipe and a water outlet pipe. The circular water cooling pipe in the center of the double-helix water cooling coil contains cooling water. The water inlet pipe and the water outlet pipe alternately spiral upward to form the double-helix water cooling coil, forming a complete water circulation loop.
[0016] Beneficial effects of the present invention:
[0017] This invention proposes a self-stabilizing, twin-helix, water-cooled premix burner. While ensuring low-NOx combustion and no flashback, it prioritizes safe ignition and eliminates the risk of explosion caused by fire extinguishing during variable load conditions. This device uses water cooling to reduce the high-temperature zone generated by gas combustion, lowering the burner's combustion temperature. Furthermore, a circular, stepped flame contact surface increases the water-cooling heat exchange area and airflow turbulence, enhancing combustion and heat transfer. Furthermore, a pilot groove allows for rapid ignition and combustion of the gas, achieving low-temperature, low-NOx, and rapid combustion.
[0018] In the present invention, the double-helix water-cooled coil spirally rises along the central axis to form a flame combustion contact surface arranged in a circular step-like shape, thereby increasing the contact area between the flame and the double-helix water-cooled coil burner, further enhancing heat transfer and reducing the combustion temperature; at the same time, an isobaric air supply mixing chamber with built-in equalizing plate 1 and equalizing plate 2 is connected at the outermost spiral tube to ensure the uniformity of the premixed gas; and an "S"-shaped connecting pipe is used to connect the water inlet pipe and the water outlet pipe at the innermost spiral tube to form a complete water circulation loop, thereby achieving countercurrent uniform cooling of the surface of the double-helix water-cooled coil burner; at the same time, a stabilizing disk is arranged at the center plane of the circular water-cooling pipe, and an ignition gun and a stabilizing burner are arranged above the stabilizing disk, and the ignition gun and the stabilizing burner are located in two adjacent areas of the "S"-shaped connecting pipe. The double-helix water-cooled premixed burner uses electronic ignition to ensure the safe ignition of the central ignition source, and spreads the flame to the surroundings through the ignition groove to achieve stable combustion of the premixed gas.
[0019] The cross-section of the double-helix water-cooling coil is a "runway" type pressure-bearing center hole structure, with hemispherical fronts at both ends and a flat side of the spiral coil, so that a spiral anti-backfire channel is formed in the middle of the consecutive adjacent double-helix water-cooling coils to ensure combustion safety; an ignition groove is provided on the combustion side surface of the double-helix water-cooling coil to quickly propagate the central flame to the outermost spiral tube to achieve rapid combustion of the premixed gas; the ignition grooves 11 are arranged at intervals of 120° along the central axis, and the fixed-distance screws are arranged at 60° intervals from the ignition grooves to fix adjacent double-helix water-cooling coils to prevent high-temperature deformation and vibration of the double-helix water-cooling coils.
[0020] The double-helix water-cooling coil includes a water inlet pipe and a water outlet pipe. The circular water-cooling pipe in the center of the double-helix water-cooling coil contains cooling water. The water inlet pipe and the water outlet pipe alternately spiral upward to form a double-helix water-cooling coil, forming a complete water circulation loop.
[0021] The combustion stabilization disk is located at the center plane of the innermost spiral tube (plane 2). It is equipped with air nozzles to provide a continuous ignition source and ensure stable combustion, preventing explosion hazards caused by flame blowout during load changes. The combustion stabilization disk contains a flame stabilizer and ignition gun. The ignition gun and flame stabilizer are located in adjacent areas of the "S"-shaped connecting pipe. The circumferential gas nozzles on the flame stabilizer are located at a plane (plane 1) higher than the center plane of the innermost spiral tube (plane 2), facilitating the diffusion of combustion. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is an AA cross-sectional view of the present invention.
[0023] Figure 2 It is a top view of the present invention.
[0024] Figure 3 For local view Figure I and local vision Figure II .
[0025] Figure 4 It is a partial view D.
[0026] Figure 5 This is a structural view of the isobaric gas supply mixing chamber.
[0027] Figure 6 This is a plan view of the innermost spiral coil.
[0028] Among them: double spiral water-cooling coil 1, hemispherical front 1a, anti-backfire channel 1b, spiral coil side 1c, circular water-cooling pipe 1d, stable combustion plate 2, air nozzle 2a, ignition gun 3, stable combustion device 4, "S"-shaped connecting pipe 5, equal pressure air supply mixing chamber 6, equalizing plate 1 6a, equalizing plate 2 6b, air pipe 7, gas pipe 8, water inlet pipe 9, water outlet pipe 10, ignition groove 11, and fixed distance screw 12. DETAILED DESCRIPTION
[0029] The present invention will be described in further detail below with reference to the accompanying drawings.
[0030] like Figures 1-6 The figure shows a double-helix water-cooled premix burner with self-stabilizing combustion characteristics. Along the airflow direction, its main structure is equipped with a double-helix water-cooled coil 1, a combustion stabilizing plate 2, an ignition gun 3, a combustion stabilizer 4, an isobaric air supply mixing chamber 6, and an ignition groove 11.
[0031] The premixed gas enters the double-helix water-cooling coil 1 after passing through the isobaric air supply mixing chamber 6. The circular step-type double-helix water-cooling coil 1 is surrounded by a water inlet pipe 9 and a water outlet pipe 10 that spiral around the central axis for multiple circles. The water inlet pipe 9 and the water outlet pipe 10 are connected by an "S"-shaped connecting pipe 5 on the plane where the innermost spiral pipe is located. The stabilizing disk 2 is placed on the central plane of the innermost spiral pipe (plane 2). The ignition gun 3 and the stabilizer 4 are located in two adjacent areas of the "S"-shaped connecting pipe 5. The gas nozzle of the stabilizer 4 and the plane where the ignition gun 3 are located (plane 1) are above the stabilizing disk 2, which is conducive to flame diffusion. At the same time, an ignition groove 11 is provided on the premixed gas combustion side of the double-helix water-cooling coil 1, and 3 groups are arranged at equal angles of 120° along the central axis to quickly ignite the premixed gas.
[0032] The working principle of the present invention is:
[0033] The present invention is provided with an isobaric air supply mixing chamber 6. The premixed gas enters the double-helix water-cooling coil 1 after passing through the isobaric air supply mixing chamber 6. Two layers of flow equalizing plates 6a and 6b are arranged in the isobaric air supply mixing chamber 6 to uniformly distribute the airflow, thereby ensuring that the airflow entering each anti-backfire channel 1d is uniform, forming a uniform flame on the combustion surface of the double-helix water-cooling coil 1, preventing local high temperature caused by uneven airflow, and ensuring safe combustion.
[0034] Furthermore, a circular stepped double-helix water-cooling coil 1 is arranged at the rear end of the isobaric air supply mixing chamber 6. The water inlet pipe 9 and the water outlet pipe 10 spiral around the central axis to form the double-helix water-cooling coil 1, forming a complete water circulation loop. This creates a circular stepped flame contact surface, increasing the contact area and enhancing combustion and heat exchange. A flashback prevention channel 1b is formed between the planes of adjacent spiral coils to prevent flashback and ensure safe combustion. Furthermore, a circular water-cooling pipe 1d, which carries cooling water, is located at the center of the double-helix water-cooling coil 1. This cools the high-temperature flue gas, lowering the temperature in the high-temperature area and further reducing NOx emissions.
[0035] Furthermore, the flame stabilizing plate 2 is placed on plane 2 at the center plane of the innermost spiral pipe, and the ignition gun 3 and the flame stabilizer 4 are placed in two adjacent areas of the "S"-shaped connecting pipe 5 to provide a continuous ignition source, ensure that the flame is not blown out by the high-speed airflow, and prevent the explosion hazard caused by the flame blowing out during the load change process; the two groups of ignition guns 3 and the flame stabilizer 4 act as double insurance to prevent unsuccessful ignition after one group is damaged; at the same time, ignition grooves 11 arranged at equal angles of 120° are provided on the combustion side of the double-helix water-cooled coil 1, and the central flame diffuses and ignites the premixed gas, and the ignition grooves 11 are used to realize rapid ignition and combustion of the premixed gas at the double-helix coil, shortening the original ignition time of the premixed gas, reducing the source emission of NOx, and realizing clean combustion.
[0036] The specific operation mode of the present invention is:
[0037] First, cooling water is passed into the circular water-cooling pipe 1d of the double-helix water-cooling coil 1 to ensure that the burner as a whole is in a water-cooling environment to prevent local high temperature generated by combustion from causing heat deformation of the burner.
[0038] Furthermore, air and gas are introduced into the air pipe 7 and the gas pipe 8 respectively, and the gas ejected from the burner 4 is ignited by electronic ignition of the ignition gun 3, forming diffuse combustion in the center of the burner.
[0039] Furthermore, the premixed main air flow is introduced into the isobaric air supply mixing chamber 6, and the central diffusion flame ignites the premixed gas, thereby solving the problem that the ignition energy of high-speed air flow is high and difficult to ignite, and at the same time preventing the explosion hazard caused by the flame being blown out during the load change process; the flame quickly propagates along the double-helix water-cooling coil 1 through the ignition groove 11 on the surface to shorten the ignition distance and achieve rapid ignition.
[0040] Furthermore, after the overall ignition is achieved, the ignition gun 3 can be turned off, and the combustion stabilizing plate 2 continues to introduce fuel gas to keep the small flame diffusing in the center stably burning.
[0041] The above content is only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention, such as changing the structure of the ignition groove 11, the use of the double-helix water-cooling coil 1 and the stable combustion plate 2 at the center axis, the ignition gun 3 and the stable combustion device 4, etc., all fall within the protection scope of the claims of the present invention.
Claims
1. A double-helix water-cooled premixed burner with self-stabilizing combustion characteristics, characterized in that: It includes a double-helix water-cooling coil (1), a flame stabilizing plate (2), an ignition gun (3), a flame stabilizing device (4), an ignition groove (11), an isobaric air supply mixing chamber (6), an "S"-shaped connecting pipe (5) and a fixed-distance screw (12); The water inlet pipe (9) and the water outlet pipe (10) constitute a double helical water cooling coil (1), the water inlet pipe (9) and the water outlet pipe (10) alternately spirally rise along the central axis to form a spiral pipe and a circular step-shaped flame combustion contact surface, the water inlet pipe (9) and the water outlet pipe (10) are fixed by means of fixed-distance screws (12), the outermost spiral pipe is connected to the isobaric air supply mixing chamber (6), and the innermost spiral pipe is connected to the water inlet pipe (9) and the water outlet pipe (10) by means of an "S"-shaped connecting pipe (5); a combustion stabilizing disk (2) is arranged on the plane of the innermost spiral pipe along the central axis direction, and an ignition gun (3) and a combustion stabilizing device (4) are provided above the outlet of the combustion stabilizing disk (2) along the air flow direction; an ignition groove (11) is provided on the combustion contact surface of the double helical water cooling coil (1); The combustion stabilizing disk (2) is placed on the center plane of the innermost spiral tube, and an air nozzle (2a) is provided on the combustion stabilizing disk (2); the ignition gun (3) and the combustion stabilizing device (4) are placed in two areas divided by the "S"-shaped connecting pipe (5), and the plane where the gas nozzles of the ignition gun (3) and the combustion stabilizing device (4) are located is arranged above the combustion stabilizing disk (2); An air pipe 7 and a gas pipe (8) are provided inside the isobaric air supply mixing chamber (6); the air pipe (7) is connected to the bottom of the combustion stabilizing plate (2), and the gas pipe (8) is connected to the bottom of the combustion stabilizing device (4); The specific operation mode of the burner is: First, cooling water is passed through the double-helix water-cooling coil (1) to ensure that the burner as a whole is in a water-cooled environment, thereby preventing local high temperatures generated by combustion from causing the burner to deform due to heat; Air and gas are introduced into the air pipe (7) and the gas pipe (8) respectively, and the gas ejected from the burner (4) is ignited by electronic ignition using the ignition gun (3), thereby forming diffuse combustion in the center of the burner; The premixed main gas flow is introduced into the isobaric gas supply mixing chamber (6), and the central diffusion flame ignites the premixed gas. The flame quickly propagates along the double-helix water-cooling coil (1) through the ignition groove (11) on the surface, shortening the ignition distance and achieving rapid ignition; After the overall ignition is achieved, the ignition gun (3) is turned off, and the combustion stabilizing plate (2) continues to introduce gas to maintain a small central diffusion flame that burns stably.
2. A double-helix water-cooled premixed burner with self-stable combustion characteristics according to claim 1, characterized in that: The cross section of the double helical water-cooling coil (1) along the central axis is a "runway" type pressure-bearing center hole structure, with hemispherical fronts (1a) at both ends, a flat side surface (1c) of the helical coil, and a circular water-cooling pipe (1d) at the center; and the sides (1c) of two adjacent helical coils form a backfire prevention channel (1b).
3. The double-helix water-cooled premixed burner with self-stable combustion characteristics according to claim 1, characterized in that: The combustion side surface of the double-helix water-cooling coil (1) is provided with an ignition groove (11), which quickly propagates the central flame to the outermost spiral tube, thereby achieving rapid combustion of the premixed gas.
4. The double-helix water-cooled premixed burner with self-stable combustion characteristics according to claim 1, characterized in that: The inlet of the isobaric air supply mixing chamber (6) includes a flow equalizing plate 1 (6a) and a flow equalizing plate 2 (6b), and the outlet of the isobaric air supply mixing chamber (6) has a double spiral water cooling coil (1) forming an isobaric circular step shape, and an ignition gun (3) pipe is provided in the center.
5. The double-helix water-cooled premixed burner with self-stable combustion characteristics according to claim 1, characterized in that: The cross section of the ignition groove (11) is semicircular, and the ignition groove (11) and the distance screw (12) are arranged at a 60° interval.
6. The double-helix water-cooled premixed burner with self-stable combustion characteristics according to claim 1, characterized in that: The double-helix water-cooling coil (1) comprises a water inlet pipe (9) and a water outlet pipe (10). The central circular water-cooling pipe (1d) of the double-helix water-cooling coil (1) contains cooling water. The water inlet pipe (9) and the water outlet pipe (10) alternately spiral upward to form the double-helix water-cooling coil (1), forming a complete water circulation loop.