Well type nitrogenization furnace tail gas pilot treatment equipment

Abstract

The present application relates to the technical field of well type nitriding furnace tail gas treatment, and discloses a well type nitriding furnace tail gas pilot ignition treatment equipment, which comprises a shell, a steam turbine, a pretreatment chamber arranged in the shell, a combustion chamber arranged in the shell, a post-treatment chamber arranged in the shell and a tail gas combustion treatment assembly arranged in the shell, wherein the tail gas combustion treatment assembly comprises a gas-solid separation part, a tail gas combustion part, a particle combustion part, a preheating part and a tail gas purification part; the gas-solid separation part is used for separating particles in the tail gas, increasing the content of combustible gas in the tail gas, then introducing combustion-supporting gas into the tail gas after the tail gas is ignited, so that the tail gas can be fully combusted, then the water in the steamer is heated, the separated particles are combusted, the chemical energy in the particles is released to heat the combustion chamber, and then the steamer is heated, thereby improving the combustion treatment efficiency of the tail gas.

Description

Technical Field

[0001] This invention relates to the field of tail gas treatment technology for pit-type nitriding furnaces, specifically to a tail gas ignition and treatment device for pit-type nitriding furnaces. Background Technology

[0002] Pit-type gas nitriding furnaces are used for gas nitriding of carbon steel parts and can also perform gas nitriding and carburizing (soft nitriding) treatment. They consist of a furnace shell, furnace lining, furnace cover lifting mechanism, furnace sealing fan, muffle tank, heating elements, and electrical control system. The furnace shell is welded from steel plates and structural steel. The furnace lining is an energy-saving composite structure constructed from high-strength, ultra-lightweight, energy-saving refractory bricks, aluminum silicate fiber, diatomaceous earth insulating bricks, and asbestos board. Pit-type nitriding furnaces are periodic operation electric furnaces. They are energy-saving resistance furnaces improved based on a series of electric furnaces, taking into account actual user needs. The maximum operating temperature is 650℃. The furnace chamber is vertical, containing a stainless steel furnace tank and a material basket. Workpieces are placed in the material basket. The atmosphere is controlled by dripping into the furnace tank via a flow meter and drip pipe. A fan mounted on the furnace cover allows for forced circulation of temperature and atmosphere within the furnace tank. The exhaust gas from pit-type nitriding furnaces contains combustible gases.

[0003] Most existing pit-type nitriding furnace exhaust gas treatment devices directly introduce the exhaust gas into the combustion furnace, where it burns and releases heat to heat water. The steam generated from the heated water drives a steam turbine, converting the heat energy into mechanical energy and then into electrical energy for storage. This method utilizes the chemical energy within the combustible gases in the exhaust gas. However, the exhaust gas contains not only combustible gases but also a large amount of non-combustible gases and waste particles. These components prevent the combustible gases from burning completely in a short time, resulting in incomplete treatment of the combustible gases in the exhaust gas. Summary of the Invention

[0004] The purpose of this invention is to provide a pit-type nitriding furnace exhaust gas ignition and treatment device to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a pit-type nitriding furnace tail gas ignition treatment device, comprising a shell and a steam turbine;

[0006] A pretreatment chamber located inside the outer casing;

[0007] The combustion chamber is located inside the outer casing;

[0008] The post-processing chamber is located inside the outer casing;

[0009] The exhaust gas combustion treatment assembly is disposed within the housing. The exhaust gas combustion treatment assembly includes a gas-solid separation section, an exhaust gas combustion section, a particulate combustion section, a preheating section, and an exhaust gas purification section. The gas-solid separation section is located in the pretreatment chamber, the exhaust gas combustion section and the particulate combustion section are located in the combustion chamber, the preheating section is located in the posttreatment chamber, and the exhaust gas purification section is located at the top of the housing. The exhaust gas passes through the gas-solid separation section, the exhaust gas combustion section, the preheating section, and the exhaust gas purification section in sequence.

[0010] Furthermore, the gas-solid separation unit includes a cyclone separator, which is fixedly installed on the inner wall of the pretreatment chamber. The input end of the cyclone separator is connected to a tail gas pipe, and the gas output end of the cyclone separator is connected to a ventilation main pipe, which extends into the tail gas combustion unit.

[0011] Furthermore, the exhaust gas combustion section includes a combustion chamber and a steamer. The combustion chamber is fixedly installed on the inner wall of the combustion chamber, and the steamer is fixedly installed on the top of the combustion chamber. The right end of the main ventilation pipe extends into the combustion chamber. An igniter is fixedly installed on the inner wall of the combustion chamber. A combustion-supporting gas pipe is connected to the front of the combustion chamber. The inner wall of the steamer is connected to the input end of the steam turbine through a pipe.

[0012] Furthermore, the pellet combustion section includes a guide plate, an igniter II, and a combustion drawer. The guide plate is located at the bottom of the cyclone separator, and the combustion drawer is slidably disposed within the combustion chamber. The right end of the guide plate is inclined toward the combustion drawer. The igniter II is fixedly installed on the inner wall of the combustion chamber. A flame-retardant plate is fixedly installed on the top inner wall of the combustion drawer, and the top of the flame-retardant plate has an air hole. A combustion-supporting gas pipe II is fixedly installed on the inner wall of the combustion drawer, and a gas pipe is fixedly installed on the inner wall of the combustion drawer. The outer walls of both the combustion-supporting gas pipe II and the gas pipe are connected to nozzles, and the nozzle openings face the flame-retardant plate.

[0013] Furthermore, the preheating unit includes a water tank, which is fixedly installed on the inner wall of the post-treatment chamber. A water inlet pipe is connected to the right outer wall of the water tank, and a drain pipe is connected to the left outer wall of the water tank. The drain pipe extends into the steamer. A valve is installed at the end of the water inlet pipe, and a one-way valve is installed at the end of the drain pipe. A bent heat-conducting pipe is fixedly installed on the inner wall of the water tank. The top end of the bent heat-conducting pipe extends outside the water tank, and a connecting pipe is connected to the bottom end of the bent heat-conducting pipe. A first venting pipe is connected to the outer wall of the connecting pipe. The left end of the first venting pipe extends into the combustion chamber. A second venting pipe is connected to the outer wall of the connecting pipe. The left end of the second venting pipe extends into the combustion chamber.

[0014] Furthermore, the exhaust gas purification unit includes a sinking pipe and a water washing tank. The water washing tank is fixedly installed on the top of the outer shell. One end of the sinking pipe extends into the water washing tank, and the other end of the sinking pipe is connected to the top of the bent heat-conducting pipe. A filter pipe is connected to the top of the water washing tank. A filter layer is fixedly installed on the inner wall of the filter pipe. An activated carbon adsorption layer is provided above the filter layer. An exhaust fan is connected to the top of the filter pipe.

[0015] Furthermore, a heat insulation sleeve is fixedly fitted on a portion of the outer wall of the steamer located outside the combustion chamber, and a U-shaped heat-conducting pipe is connected to the top of the combustion chamber. The U-shaped heat-conducting pipe extends into the steamer, and both ends of the U-shaped heat-conducting pipe are connected to the interior of the combustion chamber.

[0016] Furthermore, multiple combustion-supporting gas pipes and gas pipes are provided and are distributed at equal intervals within the combustion chamber, with the combustion-supporting gas pipes and gas pipes being arranged in a manner that alternates with one pipe between each other.

[0017] Furthermore, four bent heat-conducting pipes are provided, and four ventilation secondary pipes and four ventilation secondary pipes are provided. All four ventilation secondary pipes and four ventilation secondary pipes are connected to the same connecting pipe, and all four bent heat-conducting pipes are connected to the same connecting pipe.

[0018] Furthermore, the front of the washing tank is connected to an inlet pipe, and the back of the washing tank is connected to an outlet pipe. Valves are provided at the ends of both the outlet pipe and the inlet pipe. There are four sinking pipes, each connected to the top of a four bent heat-conducting pipe.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. The gas-solid separation unit separates particulate matter in the exhaust gas, increasing the content of combustible gas in the exhaust gas. Then, after the exhaust gas is ignited, combustion-supporting gas is introduced into the exhaust gas to ensure that the exhaust gas can be fully combusted. Then, the water in the steamer is heated to burn the separated particulate matter, releasing the chemical energy in the particulate matter to heat the combustion chamber, which in turn heats the steamer, thereby improving the combustion treatment efficiency of the exhaust gas.

[0021] 2. The high-temperature exhaust gas generated after combustion in the particulate combustion section and the exhaust gas combustion section is introduced into the connecting pipe through the ventilation auxiliary pipe 1 and ventilation auxiliary pipe 2, and then into the bent heat conduction pipe. When passing through the bent heat conduction pipe, heat exchange occurs with the water in the water tank, which cools the exhaust gas and heats the water in the water tank at the same time. The heated water is then introduced into the steam pot through the drain pipe to replenish the steam pot with water close to the boiling point, which accelerates the generation of steam in the steam pot and enables the steam pot to continuously input a stable amount of steam to the steam turbine.

[0022] 3. The cooled exhaust gas is first purified by washing it with water, then second purified by passing it through a filter layer, and finally the odor is adsorbed by an activated carbon adsorption layer. An exhaust fan is set up to accelerate the gas flow rate in the combustion chamber, combustion chamber, ventilation secondary pipe one, ventilation secondary pipe two, connecting pipe, bent heat conduction pipe, filter layer, water washing box, and filter pipe, thereby ensuring that the exhaust gas is burned and purified in a timely manner. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] Figure 2 This is a structural schematic diagram of the rear view of the outer casing of the present invention;

[0025] Figure 3 This is a structural schematic diagram of the front sectional view of the outer casing of the present invention;

[0026] Figure 4 This is a structural schematic diagram of the right-side cross-sectional view of the outer casing of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of the combustion chamber of the present invention in an exploded view;

[0028] Figure 6 This is a schematic diagram of the structure of the bent heat pipe of the present invention;

[0029] Figure 7 This is a structural schematic diagram of the water washing tank and filter tube of the present invention in a front sectional view.

[0030] In the diagram: 1. Outer shell; 2. Steam turbine; 3. Pretreatment chamber; 4. Combustion chamber; 5. Aftertreatment chamber; 6. Exhaust gas combustion treatment assembly; 61. Gas-solid separation section; 611. Exhaust gas pipe; 612. Cyclone separator; 613. Main ventilation pipe; 62. Exhaust gas combustion section; 621. Combustion chamber; 622. Igniter 1; 623. Steam pot; 624. Combustion gas pipeline 1; 63. Particle combustion section; 631. Guide plate; 632. Igniter 2; 633. Combustion drawer; 634. Flame retardant plate; 635. Combustion gas pipeline 636. Gas Pipeline; 637. Nozzle; 64. Preheating Section; 641. Water Tank; 642. Water Inlet Pipe; 643. Drain Pipe; 644. Bent Heat Conducting Pipe; 645. Connecting Pipe; 646. Ventilation Secondary Pipe One; 647. Ventilation Secondary Pipe Two; 65. Exhaust Gas Purification Section; 651. Sinking Pipe; 652. Water Washing Tank; 653. Filter Pipe; 654. Filter Layer; 655. Activated Carbon Adsorption Layer; 656. Exhaust Fan; 7. U-shaped Heat Conducting Pipe; 8. Heat Insulation Sleeve; 9. Drain Pipe; 10. Inlet Pipe. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0032] Please see Figures 1-7 The present invention provides a technical solution: a well-type nitriding furnace tail gas ignition treatment device, including a shell 1 and a steam turbine 2;

[0033] A pretreatment chamber 3 is located inside the outer casing 1;

[0034] Combustion chamber 4 is located inside the outer casing 1;

[0035] The post-processing chamber 5 is located inside the outer casing 1;

[0036] And an exhaust gas combustion treatment assembly 6 disposed inside the outer casing 1. The exhaust gas combustion treatment assembly 6 includes a gas-solid separation section 61, an exhaust gas combustion section 62, a particulate combustion section 63, a preheating section 64, and an exhaust gas purification section 65. The gas-solid separation section 61 is located in the pretreatment chamber 3, the exhaust gas combustion section 62 and the particulate combustion section 63 are located in the combustion chamber 4, the preheating section 64 is located in the aftertreatment chamber 5, and the exhaust gas purification section 65 is located at the top of the outer casing 1. The exhaust gas passes through the gas-solid separation section 61, the exhaust gas combustion section 62, the preheating section 64, and the exhaust gas purification section 65 in sequence.

[0037] The gas-solid separation unit 61 includes a cyclone separator 612, which is fixedly installed on the inner wall of the pretreatment chamber 3. The input end of the cyclone separator 612 is connected to a tail gas pipe 611, and the gas output end of the cyclone separator 612 is connected to a ventilation pipe 613. The ventilation pipe 613 extends into the tail gas combustion unit 62. The cyclone separator 612 separates the waste residue and other particulate matter mixed in the tail gas from the gas, thereby increasing the content of combustible gas in the tail gas.

[0038] The exhaust gas combustion section 62 includes a combustion chamber 621 and a steamer 623. The combustion chamber 621 is fixedly installed on the inner wall of the combustion chamber 4, and the steamer 623 is fixedly installed on the top of the combustion chamber 621. The right end of the main ventilation pipe 613 extends into the combustion chamber 621. An igniter 622 is fixedly installed on the inner wall of the combustion chamber 621. A combustion-supporting gas pipe 624 is connected to the front of the combustion chamber 621. The inner wall of the steamer 623 is connected to the input end of the turbine 2 through a pipe. The combustible gas in the exhaust gas is ignited by the igniter 622, and combustion-supporting gas is added into the combustion chamber 621 through the combustion-supporting gas pipe 624 to allow the combustible gas in the exhaust gas to be fully combusted. The heat energy released in the steamer 623 heats the water in the steamer 623, thereby generating steam. The steam enters the steam turbine 2 and drives the steam turbine 2 to generate electricity. A heat insulation sleeve 8 is fixedly fitted on a part of the outer wall of the steamer 623 outside the combustion chamber 4 to reduce the heat exchange between the steamer 623 and the outside air. A U-shaped heat conduction pipe 7 is connected to the top of the combustion chamber 621. The U-shaped heat conduction pipe 7 extends into the steamer 623, and both ends of the U-shaped heat conduction pipe 7 are connected to the inside of the combustion chamber 621. The U-shaped heat conduction pipe 7 allows the high-temperature gas in the combustion chamber 621 to enter the U-shaped heat conduction pipe 7, increasing the contact area with the water in the steamer 623 and further increasing the heat exchange efficiency between the high-temperature gas and the water.

[0039] The pellet combustion section 63 includes a guide plate 631, an igniter 632, and a combustion chamber 633. The guide plate 631 is located at the bottom of the cyclone separator 612. The combustion chamber 633 is slidably disposed within the combustion chamber 4. The right end of the guide plate 631 is inclined toward the combustion chamber 633. The igniter 632 is fixedly installed on the inner wall of the combustion chamber 4. A flame-retardant plate 634 is fixedly installed on the top inner wall of the combustion chamber 633. The top of the flame-retardant plate 634 has air holes. A combustion-supporting gas pipe 635 and a gas pipe 636 are fixedly installed on the inner wall of the combustion chamber 633. The outer walls of both the combustion-supporting gas pipe 635 and the gas pipe 636 are connected to nozzles 637. 7. The opening faces the flame-retardant plate 634. A guide plate 631 is provided to guide the particles separated by the cyclone separator 612 onto the flame-retardant plate 634. The combustion-supporting gas and gas are discharged through the second combustion-supporting gas pipe 635 and the gas pipe 636, and then ignited by the second igniter 632, thereby heating the particles and causing the combustible particles to burn and release heat energy. There are multiple second combustion-supporting gas pipes 635 and gas pipes 636, which are evenly distributed in the combustion drawer 633. The second combustion-supporting gas pipes 635 and gas pipes 636 are distributed in a way that alternates one with each other to ensure that the gas and combustion-supporting gas are evenly distributed on the flame-retardant plate 634, so as to fully heat and burn the particles on the flame-retardant plate 634.

[0040] The preheating unit 64 includes a water tank 641, which is fixedly installed on the inner wall of the post-processing chamber 5. A water inlet pipe 642 is connected to the right outer wall of the water tank 641, and a drain pipe 643 is connected to the left outer wall of the water tank 641. The drain pipe 643 extends into the steamer 623. A valve is installed at the end of the water inlet pipe 642, and a one-way valve is installed at the end of the drain pipe 643. A bent heat-conducting pipe 644 is fixedly installed on the inner wall of the water tank 641, with its top end extending into... Outside the water tank 641, a connecting pipe 645 is connected to the bottom end of the bent heat conduction pipe 644. A first vent pipe 646 is connected to the outer wall of the connecting pipe 645. The left end of the first vent pipe 646 extends into the combustion chamber 4. A second vent pipe 647 is connected to the outer wall of the connecting pipe 645. The left end of the second vent pipe 647 extends into the combustion chamber 621. The high-temperature combustion gas generated in the particulate combustion section 63 and the exhaust gas combustion section 62 is dissipated through the first vent pipe 646 and the second vent pipe 647. The warm exhaust gas is introduced into the connecting pipe 645, and then into the bent heat-conducting pipe 644. While passing through the bent heat-conducting pipe 644, it exchanges heat with the water in the water tank 641, cooling the exhaust gas while heating the water in the water tank 641. The heated water is then introduced into the steam boiler 623 through the drain pipe 643, replenishing the steam boiler 623 with water nearing its boiling point, accelerating the generation of steam in the steam boiler 623, and enabling the steam boiler 623 to continuously and stably supply steam to the steam turbine 2. There are four pipes 644, four ventilation secondary pipes 647 and four ventilation secondary pipes 646, and all four ventilation secondary pipes 646 and 647 are connected to the same connecting pipe 645. All four bent heat conduction pipes 644 are connected to the same connecting pipe 645. The multiple bent heat conduction pipes 644 increase the heat exchange area between the exhaust gas and water. The multiple ventilation secondary pipes 646 and 647 are used to increase the flow channel of exhaust gas in the combustion chamber 4 and combustion cavity 621.

[0041] The exhaust gas purification unit 65 includes a sinking pipe 651 and a water washing tank 652. The water washing tank 652 is fixedly installed on the top of the outer casing 1. One end of the sinking pipe 651 extends into the water washing tank 652, and the other end of the sinking pipe 651 is connected to the top of the bent heat-conducting pipe 644. A filter pipe 653 is connected to the top of the water washing tank 652. A filter layer 654 is fixedly installed on the inner wall of the filter pipe 653. An activated carbon adsorption layer 655 is installed above the filter layer 654. An exhaust fan 656 is connected to the top of the filter pipe 653. The cooled exhaust gas is first purified by water washing, then second purified by the filter layer 654, and finally the odor is adsorbed by the activated carbon adsorption layer 655. The exhaust fan 656 is used to accelerate the combustion chamber 62. 1. The gas flow rate within the combustion chamber 4, ventilation secondary pipe 1 646, ventilation secondary pipe 2 647, connecting pipe 645, bent heat conduction pipe 644, filter layer 654, water washing tank 652, and filter pipe 653 ensures timely combustion and purification of exhaust gas. A liquid inlet pipe 10 is connected to the front of the water washing tank 652, and a liquid drain pipe 9 is connected to the back. Valves are installed at the ends of both the liquid drain pipe 9 and the liquid inlet pipe 10. The liquid inlet pipe 10 and the liquid drain pipe 9 are used to replace the washing liquid in the water washing tank 652. Four sinking pipes 651 are provided, each connected to the top of one of the four bent heat conduction pipes 644, increasing the passage for exhaust gas to enter the water washing tank 652 and allowing more contact between the exhaust gas and the washing liquid in the water washing tank 652.

[0042] Working principle: During use, exhaust gas is introduced into exhaust pipe 611. After entering cyclone separator 612, the exhaust gas is separated and fixed by cyclone separator 612. The gas enters combustion chamber 621 through main ventilation pipe 613, while the solids fall onto guide plate 631 and then slide onto flame retardant plate 634. Ignition device 622 is turned on to ignite the gas in combustion chamber 621. At the same time, combustion-supporting gas is introduced into combustion chamber 621 through combustion-supporting gas pipe 624, allowing the combustible gas in the exhaust gas to burn completely. During the combustion process of the combustible gas... The released heat energy heats the water in the steamer 623, generating steam. The steam enters the steam turbine 2, driving it to generate electricity. The steam then discharges the combustion-supporting gas and gas towards the flame-retardant plate 634 through the combustion-supporting gas pipe 635 and the gas pipe 636. Igniter 632 ignites the combustion-supporting gas and gas, heating the particulate matter and causing it to burn, releasing heat energy. This heat energy heats the steamer 623 in the combustion chamber 4. Ventilation pipes 646 and 647 further fuel the combustion of the particulate matter. The high-temperature exhaust gas generated after combustion in section 63 and exhaust gas combustion section 62 is introduced into connecting pipe 645, and then into bent heat conduction pipe 644. As it passes through bent heat conduction pipe 644, it exchanges heat with water in water tank 641, cooling the exhaust gas while heating the water in water tank 641. The heated water is then introduced into steam boiler 623 through drain pipe 643, replenishing the steam boiler 623 with water near its boiling point, accelerating steam generation in steam boiler 623, and enabling steam boiler 623 to continuously and stably supply steam to steam turbine 2. The heated exhaust gas is introduced into the water washing tank 652 for water washing and first purification. Then it passes through the filter layer 654 for second purification. Finally, it passes through the activated carbon adsorption layer 655 to adsorb the odor. An exhaust fan 656 is set to accelerate the gas flow rate in the combustion chamber 621, combustion chamber 4, ventilation secondary pipe 1 646, ventilation secondary pipe 2 647, connecting pipe 645, bent heat conduction pipe 644, filter layer 654, water washing tank 652, and filter pipe 653, thereby ensuring that the exhaust gas is burned and purified in a timely manner.

[0043] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

Claims

1. A pit-type nitriding furnace tail gas ignition treatment device, comprising an outer shell (1) and a steam turbine (2); A pretreatment chamber (3) is located inside the outer shell (1); Combustion chamber (4) located inside the outer casing (1); The post-processing chamber (5) is located inside the outer shell (1); And the exhaust gas combustion treatment assembly (6) disposed within the housing (1), characterized in that: The exhaust gas combustion treatment assembly (6) includes a gas-solid separation section (61), an exhaust gas combustion section (62), a particulate combustion section (63), a preheating section (64), and an exhaust gas purification section (65). The gas-solid separation section (61) is located in the pretreatment chamber (3), the exhaust gas combustion section (62) and the particulate combustion section (63) are located in the combustion chamber (4), the preheating section (64) is located in the posttreatment chamber (5), and the exhaust gas purification section (65) is located at the top of the outer shell (1). The exhaust gas passes through the gas-solid separation section (61), the exhaust gas combustion section (62), the preheating section (64), and the exhaust gas purification section (65) in sequence. The gas-solid separation unit (61) includes a cyclone separator (612), which is fixedly installed on the inner wall of the pretreatment chamber (3). The input end of the cyclone separator (612) is connected to a tail gas pipe (611), and the gas output end of the cyclone separator (612) is connected to a ventilation pipe (613). The ventilation pipe (613) extends into the tail gas combustion unit (62). The exhaust gas combustion section (62) includes a combustion chamber (621) and a steamer (623). The combustion chamber (621) is fixedly installed on the inner wall of the combustion chamber (4). The steamer (623) is fixedly installed on the top of the combustion chamber (621). The right end of the vent pipe (613) extends into the combustion chamber (621). An igniter (622) is fixedly installed on the inner wall of the combustion chamber (621). A combustion-supporting gas pipe (624) is connected to the front of the combustion chamber (621). The inner wall of the steamer (623) is connected to the input end of the steam turbine (2) through a pipe. The pellet combustion section (63) includes a guide plate (631), an igniter (632), and a combustion drawer (633). The guide plate (631) is located at the bottom of the cyclone separator (612), and the combustion drawer (633) is slidably disposed within the combustion chamber (4). The right end of the guide plate (631) is inclined toward the combustion drawer (633). The igniter (632) is fixedly installed on the inner wall of the combustion chamber (4), and the top of the combustion drawer (633) is... A flame-retardant plate (634) is fixedly installed on the inner wall of the combustion chamber. The top of the flame-retardant plate (634) is provided with an air hole. A second combustion-supporting gas pipe (635) is fixedly installed on the inner wall of the combustion chamber (633). A gas pipe (636) is fixedly installed on the inner wall of the combustion chamber (633). A nozzle (637) is provided on the outer wall of both the second combustion-supporting gas pipe (635) and the gas pipe (636). The nozzle (637) opens towards the flame-retardant plate (634).

2. The tail gas ignition and treatment equipment for a pit-type nitriding furnace according to claim 1, characterized in that: The preheating unit (64) includes a water tank (641), which is fixedly installed on the inner wall of the post-processing chamber (5). A water inlet pipe (642) is connected to the right outer wall of the water tank (641), and a drain pipe (643) is connected to the left outer wall of the water tank (641). The drain pipe (643) extends into the steamer (623). A valve is installed at the end of the water inlet pipe (642), and a one-way valve is installed at the end of the drain pipe (643). The inner wall of the water tank (641) is fixedly installed with… There is a bent heat conduction pipe (644), the top end of which extends into the water tank (641), and the bottom end of which is connected to a connecting pipe (645). The outer wall of the connecting pipe (645) is connected to a first ventilation pipe (646), the left end of which extends into the combustion chamber (4). The outer wall of the connecting pipe (645) is connected to a second ventilation pipe (647), the left end of which extends into the combustion chamber (621).

3. The tail gas ignition and treatment equipment for a pit-type nitriding furnace according to claim 1, characterized in that: The exhaust gas purification unit (65) includes a sinking pipe (651) and a water washing tank (652). The water washing tank (652) is fixedly installed on the top of the outer shell (1). One end of the sinking pipe (651) extends into the water washing tank (652), and the other end of the sinking pipe (651) is connected to the top of the bent heat conduction pipe (644). A filter pipe (653) is connected to the top of the water washing tank (652). A filter layer (654) is fixedly installed on the inner wall of the filter pipe (653). An activated carbon adsorption layer (655) is provided above the filter layer (654). An exhaust fan (656) is connected to the top of the filter pipe (653).

4. The tail gas ignition and treatment equipment for a pit-type nitriding furnace according to claim 1, characterized in that: The steamer (623) is fitted with a heat insulation sleeve (8) on a part of the outer wall outside the combustion chamber (4). A U-shaped heat-conducting pipe (7) is connected to the top of the combustion chamber (621). The U-shaped heat-conducting pipe (7) extends into the steamer (623), and both ends of the U-shaped heat-conducting pipe (7) are connected to the interior of the combustion chamber (621).

5. The tail gas ignition treatment equipment for a pit-type nitriding furnace according to claim 1, characterized in that: Multiple combustion-supporting gas pipes (635) and gas pipes (636) are provided and are distributed at equal intervals in the combustion drawer (633). The combustion-supporting gas pipes (635) and gas pipes (636) are distributed in a manner that alternates one with each other.

6. The tail gas ignition and treatment equipment for a pit-type nitriding furnace according to claim 2, characterized in that: Four bent heat-conducting pipes (644) are provided, and four ventilation secondary pipes (647) and four ventilation secondary pipes (646) are provided. All four ventilation secondary pipes (646) and four ventilation secondary pipes (647) are connected to the same connecting pipe (645), and all four bent heat-conducting pipes (644) are connected to the same connecting pipe (645).

7. The tail gas ignition and treatment equipment for a pit-type nitriding furnace according to claim 3, characterized in that: The front of the washing tank (652) is connected to an inlet pipe (10), and the back of the washing tank (652) is connected to a drain pipe (9). Valves are provided at the ends of the drain pipe (9) and the inlet pipe (10). There are four sinking pipes (651), which are connected to the top of four bent heat-conducting pipes (644) respectively.

Images