Direct-fired low-concentration gas burner

Abstract

This utility model relates to the field of burners, specifically a direct-fired low-concentration gas burner. A direct-fired low-concentration gas burner includes a burner head and a casing connected together. A central flame ventilation duct and an outer flame ventilation duct are provided on one side of the casing, each duct containing an adjustment device. An ignition device and a flame detection device are provided on the outside of the burner head. It also includes a flame-retardant spray and a safety protection body. The flame-retardant spray is located inside the burner head, with multiple individual flame-retardants distributed circumferentially. The safety protection body is located inside the casing near one end of the burner head. After entering the casing, the central flame ventilation duct passes sequentially through the safety protection body and the flame-retardant spray, with its free end flush with the front end of the burner. It features high energy efficiency, safety and stability, and high thermal efficiency.

Description

Technical Field

[0001] This utility model relates to the field of burners, specifically a direct-fired low-concentration gas burner. Background Technology

[0002] The extraction of oil and coal releases a large amount of methane gas, the main combustible component of which is methane. Methane has a greenhouse effect 25 times that of CO2, and its effective utilization will greatly reduce environmental damage.

[0003] The main combustible component of gas is methane. If the concentration of methane in the gas is low, it usually needs to be purified or mixed with high-heat gas. Although this operation can improve combustion efficiency, it increases the cost of using gas.

[0004] The theoretical air-fuel ratio for methane combustion is approximately 1:10, at which thermal efficiency is highest. However, methane concentrations in air between 5% and 15% are prone to explosion upon ignition. Low-concentration methane gas has a concentration range of 5% to 9%, falling within the explosive limits, making its use in traditional industrial production extremely difficult. However, if stable combustion of methane gas within these explosive limits can be ensured, its direct application in industrial boilers would significantly improve thermal efficiency, reduce production costs, and have substantial environmental benefits. Utility Model Content

[0005] This invention addresses the problems mentioned in the background art, such as low thermal efficiency, high operating costs, and significant safety hazards in the use of traditional gas, by providing a direct-fired low-concentration gas burner.

[0006] To achieve the above technical objectives, the technical solution adopted by this utility model is: a direct-fired low-concentration gas burner, comprising a burner head and a casing connected together, with a central flame ventilation duct and an outer flame ventilation duct provided on one side of the casing, and adjusting devices installed inside each duct; an ignition device and a flame detection device are provided on the outside of the burner head.

[0007] It also includes sprayed flame retardants and safety protection bodies;

[0008] The sprayed flame retardant is disposed inside the combustion head, with multiple flame retardant units distributed circumferentially.

[0009] The safety protection body is located inside the casing near the burner head.

[0010] After entering the housing, the central flame ventilation duct passes through the safety protection body and the sprayed flame retardant body in sequence, with its free end flush with the front end of the burner.

[0011] As a preferred technical solution: the sprayed flame retardant body is composed of multiple flame retardant body units; each flame retardant body unit includes a front honeycomb ceramic body and a rear metal shavings filling part, with a high-temperature resistant layer between the two, the high-temperature resistant layer wrapping the outside of the metal shavings filling part, a fire-retardant sheet being provided on the rear end face, and an unshaped refractory material being wrapped around the outside of the honeycomb ceramic body; the fire-retardant sheet, the compressed metal shavings filling part and the high-temperature resistant layer are cast into a whole by the unshaped refractory material to form a flame retardant body unit.

[0012] As a preferred technical solution: multiple flame-retardant monomers are evenly arranged along the circumference and set inside the ports of the casing and the central flame ventilation duct; the spaces between each flame-retardant monomer are filled with monolithic refractory material.

[0013] As a preferred technical solution: the interior of the honeycomb ceramic body has a capillary porous structure with a pore size of less than 2.5 x 2.2 mm.

[0014] As a preferred technical solution: the high-temperature resistant layer is a bowl-shaped structure made of high-temperature resistant iron-chromium-aluminum woven fiber felt, the body of which has a capillary structure and is filled with metal shavings inside.

[0015] As a preferred technical solution: the safety protection body is a combined disc-shaped structure, with zero clearance between its outer wall and the inner wall of the outer casing; the safety protection body includes a circular flame arrestor plate installed inside the central flame ventilation duct, and an annular flame arrestor plate installed on the inner wall of the casing and fitted outside the central flame ventilation duct; the installation gaps of each flame arrestor plate in the safety protection body are filled with asbestos.

[0016] As a preferred technical solution, a temperature measuring device is installed between the casing and the burner head.

[0017] Compared with existing technologies, the burner disclosed in this utility model uses 5-9% low-concentration methane gas as fuel and achieves efficient energy utilization through direct combustion. It employs flame-retardant combustion technology to achieve direct combustion of methane gas, and uses safety protection devices to ensure safe and stable combustion, enabling stable combustion within the explosion limit range. The flame temperature generated by combustion is 1000-1900℃, with high thermal efficiency. It can be directly applied to industrial boilers to achieve efficient utilization of methane gas. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0019] Figure 2 This is a schematic diagram of the cross-sectional structure of the flame-retardant spray body in this utility model.

[0020] Figure 3 This is a schematic diagram of the structure of the flame retardant monomer in this utility model.

[0021] Figure 4 This is a schematic diagram of the cross-sectional structure of the honeycomb ceramic body in this utility model.

[0022] Figure 5 This is a schematic diagram of the structure of the safety protection body in this utility model.

[0023] In the diagram: 1. Combustion head; 2. Housing; 3. Sprayed flame retardant body; 3-1. Honeycomb ceramic body; 3-2. Unshaped refractory material; 3-3. High-temperature resistant layer; 3-4. Flame arrestor; 3-5. Metal filling part; 4. Safety protection body; 4-1. Circular flame arrestor; 4-1. Ring flame arrestor; 4-3. Asbestos; 5. Temperature measuring device; 6. Central flame adjusting device; 7. Outer flame adjusting device; 8. Ignition device; 9. Flame detection device; 10. Central flame ventilation duct; 11. Outer flame ventilation duct. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] This utility model discloses a high-efficiency direct-fired low-concentration gas burner that uses 5-9% low-concentration gas as fuel. Under the premise of ensuring no explosion or backfire occurs, it generates a high-temperature flame of 1000-1900℃ during combustion. Applied to industrial boilers for heating, this process efficiently utilizes the low-concentration gas, achieving energy conservation and environmental protection. See the attached diagram for the specific structure of the burner. Figure 1-5 .

[0026] This direct-fired low-concentration gas burner includes a burner head 1 and a casing 2 connected together. A central flame ventilation duct 10 and an outer flame ventilation duct 11, both communicating with the inside of the casing 2, are located on the right side of the casing 2. Each duct contains an adjustment device: a central flame adjustment device 6 and an outer flame adjustment device 7. An ignition device 8 and a flame detection device 9 are installed on both sides of the burner head 1. A temperature measuring device 5 is installed between the casing 2 and the burner head 1 to monitor the internal temperature of the casing in real time, enabling timely adjustments to the central flame adjustment device 6 and the outer flame adjustment device 7.

[0027] The housing 2 is also equipped with a flame-retardant spray body 3 and a safety protection body 4. The flame-retardant spray body 3 is located inside the burner head 1, with multiple flame-retardant individual units distributed circumferentially. The safety protection body 4 is located inside the housing 2 near one end of the burner head 1. After the central flame ventilation duct 10 enters the housing 2, it passes through the safety protection body 4 and the flame-retardant spray body 3 in sequence, with its free end flush with the front end of the burner 1.

[0028] As a preferred embodiment, the sprayed flame retardant body 3 is composed of multiple flame retardant body units. Each flame retardant body unit includes a front honeycomb ceramic body 3-1 and a rear metal shavings filling part 3-5, with a high-temperature resistant layer 3-3 disposed between them. The high-temperature resistant layer 3-3 wraps around the metal shavings filling part 3-5, and a flame-retardant sheet 3-4 is disposed on the rear end face. The honeycomb ceramic body 3-1 is wrapped with an unshaped refractory material 3-2. The flame-retardant sheet, the compressed metal shavings filling part, and the high-temperature resistant layer are cast into a whole by the unshaped refractory material to form a flame retardant body unit. Multiple flame retardant body units are evenly arranged along the circumference and disposed in the ports of the casing 2 and the central flame ventilation duct 10. The spaces between each flame retardant body unit are filled with unshaped refractory material 3-2 to achieve sealing.

[0029] As a preferred embodiment, the honeycomb ceramic body 3-1 is a high-temperature resistant, low-thermal-conductivity ceramic with a capillary porous structure and square holes with a pore size less than 2.5 x 2.2 mm, generally between 2.0 and 2.5 mm. This ensures that the gas is ejected at high speed without backfire. The low thermal conductivity ensures that the heat in the furnace is not conducted to the burner body. The gas can cool the honeycomb ceramic body 3-1 as it passes through, preventing heat conduction and forming a fourth layer structure.

[0030] As another preferred embodiment, the high-temperature resistant layer 3-3 is a bowl-shaped structure made of high-temperature resistant iron-chromium-aluminum woven fiber felt, such as... Figure 3 The structure shown contains a metal shavings filling section 3-5 inside. The main body of the iron-chromium-aluminum woven fiber felt has a capillary structure, which can play a fire-retardant role and ensure the passage of gas, forming a third layer structure.

[0031] As another preferred embodiment, the metal shavings filling part 3-5 consists of compressed metal shavings, which fill the gaps and ensure a tight, seamless fit between the honeycomb ceramic body and the iron-chromium-aluminum woven fiber felt. The metal shavings accumulate together to form a porous structure, allowing gas to pass through smoothly and forming a second layer.

[0032] As another preferred embodiment, the fire-arresting sheet 3-4 is a metal fire-arresting sheet, forming the first layer of the structure.

[0033] The flame-retardant sheet, metal shavings filling section, iron-chromium-aluminum woven fiber felt, and honeycomb ceramic body are cast into a single flame-retardant unit through an outer layer of unshaped refractory material, providing overall flame-retardant properties. Multiple flame-retardant units are evenly arranged along the circumference and installed inside the combustion head. The gaps between the units and the installation seams are filled with unshaped refractory material, forming a single sprayed flame-retardant unit.

[0034] In another preferred embodiment, the safety protection body 4 is a combined disc-shaped structure, including a circular flame arrestor 4-1 installed inside the central flame ventilation duct 10, and an annular flame arrestor 4-2 installed on the inner wall of the housing 2 and fitted over the central flame ventilation duct 10. Asbestos 4-3 is filled in the gaps between the flame arrestors in the safety protection body 4 and the inner wall of the housing or the outer wall of the duct to ensure a seamless fit, thereby providing flame arrest and preventing backfire when the burner head is damaged, thus reducing the incidence of safety accidents.

[0035] As a preferred option, during installation, a baffle can be welded at a designated position on the inner wall of the central flame ventilation duct 10 and the inner wall of the casing 2. After placing the circular flame arrestor plate 4-1 and the annular flame arrestor plate 4-2, another baffle is welded on the other side to achieve the positioning of the safety protection body.

[0036] The working process of this utility model is as follows: When the burner is working, low-concentration methane gas enters through the central flame ventilation duct 10 and the outer flame ventilation duct 11, and after being adjusted by the central flame adjustment device 6 and the outer flame adjustment device 7, it enters the casing 2, passes through the safety protection body 4, and reaches the burner head 1 where it is sprayed out by the flame-retardant spray body 3, leaving the burner. At this time, the ignition device 8 discharges and ignites the low-concentration methane gas, and the flame is detected by the flame detection device 9. The flame-retardant spray body 3 plays a role in flame retardancy and high-speed injection of low-calorific-value methane gas during the combustion process, which is the first level of safety protection; the safety protection body 4 has a flame-retardant function, which is the second level of safety protection, further ensuring safety; the temperature measuring device 5 provides real-time safety detection for combustion, ensuring the normal operation of the burner; the central flame adjustment device 6 and the outer flame adjustment device 7 can adjust the burner power to ensure that the burner operates accurately at the required power.

[0037] The working principle of this patent is:

[0038] 1. Flame-retardant combustion technology is employed: The flame-retardant spray body 3 of this invention is made of high-temperature resistant ceramic with a porous capillary structure. Calculations are performed based on the flame velocity of gas combustion to ensure that the size of the capillary pores in the flame-retardant spray body is much smaller than the gas quenching diameter and quenching length. The placement of the flame-retardant spray body 3 ensures that backfire does not occur during combustion. Furthermore, after the gas leaves the flame-retardant spray body at high speed from the burner body, it burns rapidly, forming a high-temperature flame of 1000-1900℃, providing a heat source for industrial boilers.

[0039] 2. Safe and stable combustion technology within the explosion limits: A safety protection body 4 is installed inside the casing. This safety protection body is a metal braided flame-retardant structure with flame-retardant function, and there is a zero-gap fit between the safety protection body and the burner casing. If the flame penetrates the sprayed flame-retardant material, the safety protection body isolates the flame, preventing the flame from entering the casing and causing significant damage.

[0040] A temperature measuring device 5 and a flame detection device 9 are installed on the casing. When the flame passes through the sprayed flame retardant, it can be detected in time, and the gas supply can be cut off to ensure safety. The flame temperature after combustion of the gas burner is as high as 1000-1900℃, which greatly reduces the excess air coefficient and also relatively reduces the amount of flue gas. Compared with combustion methods with a high excess air coefficient, it reduces the heat loss of flue gas. Therefore, the direct-fired low-concentration gas burner has high thermal efficiency in industrial boilers.

[0041] The above-disclosed embodiments are merely specific examples of this patent, but this patent is not limited thereto. Any variations that can be conceived by those skilled in the art should fall within the protection scope of this patent.

Claims

1. A direct-fired low-concentration gas burner, comprising a burner head and a casing connected together, wherein a central flame ventilation duct and an outer flame ventilation duct are provided on one side of the casing, and each duct is equipped with an adjustment device; an ignition device and a flame detection device are provided on the outside of the burner head, characterized in that: It also includes sprayed flame retardants and safety protection bodies; The sprayed flame retardant is disposed inside the combustion head, with multiple flame retardant units distributed circumferentially. The safety protection body is located inside the casing near the burner head. After entering the housing, the central flame ventilation duct passes through the safety protection body and the sprayed flame retardant body in sequence, with its free end flush with the front end of the burner.

2. The direct-fired low-concentration gas burner according to claim 1, characterized in that, The sprayed flame retardant is composed of multiple flame retardant units; Each flame-retardant unit consists of a front honeycomb ceramic body and a rear metal shavings filling part, with a high-temperature resistant layer between them. The high-temperature resistant layer wraps around the metal shavings filling part, and a flame-retardant sheet is provided on the rear end face. The honeycomb ceramic body is wrapped with an unshaped refractory material. The flame-retardant sheet, the compressed metal shavings filling part and the high-temperature resistant layer are cast into a whole by the unshaped refractory material to form a flame-retardant unit.

3. The direct-fired low-concentration gas burner according to claim 2, characterized in that, Multiple flame-retardant units are evenly arranged along the circumference and are respectively installed in the ports of the casing and the central flame ventilation duct; the spaces between each flame-retardant unit are filled with monolithic refractory material.

4. The direct-fired low-concentration gas burner according to claim 2, characterized in that, The honeycomb ceramic body has a capillary porous structure with a pore size of less than 2.5 x 2.2 mm.

5. The direct-fired low-concentration gas burner according to claim 2, characterized in that, The high-temperature resistant layer is a bowl-shaped structure made of high-temperature resistant iron-chromium-aluminum woven fiber felt. Its body has a capillary structure and is filled with metal shavings inside.

6. The direct-fired low-concentration gas burner according to claim 1, characterized in that, The safety protection body is a combined disc-shaped structure with zero clearance between its outer wall and the inner wall of the outer casing; the safety protection body includes a circular flame arrestor plate installed inside the central flame ventilation duct, and an annular flame arrestor plate installed on the inner wall of the casing and fitted outside the central flame ventilation duct; the installation gaps of each flame arrestor plate in the safety protection body are filled with asbestos.

7. The direct-fired low-concentration gas burner according to claim 1, characterized in that, A temperature measuring device is installed between the casing and the burner head.

Images