Waste heat boiler with deoxidizing, dedusting and denitration functions
Through the design of waste heat boiler with integrated dust removal, denitrification and oxygen removal functions, the existing waste heat boiler has solved the problem of handling complex industrial waste gas, achieving the effect of compact equipment, efficient energy utilization and fewer faults.
Patent Information
- Application Number
- CN202422311540.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2025-08-01
- Estimated Expiration
- 2034-09-23
AI Technical Summary
Existing waste heat boilers are difficult to effectively deal with complex industrial waste gas, resulting in ash blockage on the boiler's heated surface and severe low-temperature corrosion. The equipment covers a large area, high investment costs, and large energy losses.
Design a waste heat boiler with dust removal, denitrification and deoxygenation functions, integrating dust removal device, denitrification device, boiler body, deoxygenation device, heat pipe heat exchanger and water heat exchanger. Through a compact connection structure, a multi-tube box structure and a cascade use of evaporators are adopted to reduce equipment resistance and energy losses.
It achieves compact equipment, small footprint and high energy utilization efficiency, reduces equipment failures, reduces power consumption, extends equipment life, improves heat exchange effect, and avoids ash blockage and catalyst failure.
Smart Images
Figure CN223178806U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of industrial waste heat utilization, and particularly relates to a waste heat boiler with deoxidation, dust removal and denitration functions. Background Art
[0002] Industrial waste gas waste heat has high waste heat utilization value, but its flue gas components contain harmful components such as NOx, SO2, dust, etc. that pollute the atmosphere, and the dust components are complex. This brings certain difficulties to the industrial waste heat recovery and utilization. As the main equipment for industrial waste heat recovery and utilization, the waste heat boiler in the related technology only includes the heating surface of the boiler body, and it is difficult to adapt to a variety of industrial waste gas conditions, resulting in serious ash fouling on the boiler heating surface and serious low-temperature corrosion on the tail heating surface. Moreover, the flue gas discharged from the boiler needs to pass through special flue gas purification equipment to meet the emission standards. The boiler body and the auxiliary supporting flue gas purification equipment cover a large area, have high equipment investment costs, and have many external connecting pipes, resulting in large temperature losses and resistance losses, causing energy losses, and sufficient fan equipment needs to be configured to overcome the resistance of the equipment and pipeline system, consuming a large amount of electricity.
[0003] How to effectively integrate waste heat utilization and environmental protection facilities has become the key research direction in the field of industrial waste gas waste heat utilization. Due to the complex components of industrial waste gas and the complex dust components, and the variety of environmental protection facilities, it is difficult to organically integrate them into the boiler. Different treatment processes need to be adopted according to the flue gas components and dust components. Summary of the Invention
[0004] In view of this, the utility model aims to solve at least one of the related technical problems to a certain extent.
[0005] To achieve the above object, the technical solution of the utility model is realized as follows:
[0006] A waste heat boiler with deoxidation, dust removal and denitration functions includes a dust removal device, a denitration device, a boiler body, a deaerator, a connection structure, a heat pipe heat exchanger and a water-water heat exchanger;
[0007] The dust removal device is arranged at the flue gas inlet end of the boiler body, and the heat pipe heat exchanger is detachably connected to the flue gas outlet end of the boiler body through the connection structure;
[0008] A feed water pump is arranged at the water side inlet of the heat pipe heat exchanger, a three-way valve is arranged at the water side outlet of the heat pipe heat exchanger, one end of the three-way valve is connected to the inlet of the water-water heat exchanger, and the other end of the three-way valve is connected to the economizer of the boiler body;
[0009] The water outlet end of the deaerator is connected to the heat pipe heat exchanger through a feed water pump, and the water inlet end of the deaerator is connected to the water outlet end of the water-water heat exchanger;
[0010] The denitration device is arranged inside the boiler body.
[0011] Further, the boiler body includes a boiler shell, a superheater, a superheater desuperheating device (2a), a first-stage evaporator, a steam drum, a second-stage evaporator, an evaporator for the deaerator, and a economizer. The superheater, the superheater desuperheating device (2a), the first-stage evaporator, the steam drum, the second-stage evaporator, the evaporator for the deaerator, and the economizer are arranged in the boiler shell in sequence. The number of evaporator and economizer stages can be designed and determined according to the inlet flue gas parameters and the exhaust gas parameters of the boiler. One end of the boiler shell is a vertical flue, and the other end of the boiler shell is a horizontal flue. The vertical flue is connected to the dust removal device, and the horizontal flue is connected to the heat pipe heat exchanger. The boiler shell is in an inverted "U" shape. The heating surface of the vertical flue is of a multi-tube box structure. A plurality of the tube box structures are stacked upward, and a welding method is adopted between the plurality of tube box structures. After the boiler is heated, it expands thermally upward as a whole.
[0012] Further, the water-water heat exchanger is provided with a water outlet and two water inlets. One water inlet is connected to the low-temperature feed water, and the other water inlet is connected to a three-way valve through a pipeline. The water outlet is connected to the inlet header of the deaerator and the economizer.
[0013] Further, the connection structure includes a fixed sleeve, a connection sleeve, a first connecting pipe, a second connecting pipe, a sealing structure, two flange plates, and a plurality of locking structures. The two flange plates are connected and fixed through the plurality of locking structures. One flange plate is connected to the horizontal flue through the first connecting pipe, and the other flange plate is connected to the heat pipe heat exchanger through the second connecting pipe. The fixed sleeve and the connection sleeve are respectively fixedly connected to one flange plate. The connection sleeve is arranged outside the fixed sleeve, and the sealing structure is arranged between the connection sleeve and the fixed sleeve.
[0014] Further, the sealing structure includes a sealing groove and a plurality of sealing rubber rings. The sealing groove is arranged on the inner end face of the flange plate, and the sealing groove can cooperate with the end of the connection sleeve. The plurality of sealing rubber rings are arranged in a row on the outer wall of the fixed sleeve.
[0015] Further, the locking structure includes a locking screw and two fixing nuts. The locking screw penetrates through the two flange plates, and the locking screw is connected and fixed to the two flange plates through the two fixing nuts.
[0016] Further, the dust removal device is a cyclone dust removal device.
[0017] Compared with the prior art, the waste heat boiler with deoxygenation, dust removal and denitration functions of the present utility model has the following advantages:
[0018] 1. The waste heat boiler has the functions of dust removal, denitration and deoxygenation, with a compact structure, small floor area of the equipment, few external flue gas pipelines, small equipment resistance, reducing the overall equipment investment, greatly reducing the temperature loss and resistance loss of the external flue gas and air pipelines, improving the heat utilization efficiency and reducing the power consumption of the equipment.
[0019] 2. The boiler equipment has fewer failures. After the flue gas is dust-removed, the fouling of the boiler heating surface is reduced, the heat transfer effect is improved, and it is not easy to block ash; after the flue gas is dust-removed, it is beneficial to the efficient and stable operation of the denitration equipment. The denitration reactor is not easy to block ash, and the catalyst is not easy to fail due to ash blockage or poisoning, and can operate efficiently and stably for a long time.
[0020] 3. The heating surface of the vertical flue is of a multi-tube box structure, reducing the weight of the boiler steel structure and the overall weight. The tube boxes are welded to each other, which is convenient for on-site installation, removal and replacement. It replaces the connection between the heating surfaces of the traditional boiler with expansion joints, and the boiler air leakage often occurs due to the tearing of the expansion joints caused by thermal fatigue.
[0021] 4. A special evaporator is used as the heat source for thermal deoxygenation. The deaerator operates at constant pressure / sliding pressure, with strong adaptability and conforming to the cascade utilization of energy. The saturated steam generated by the evaporator on the low-temperature side of the boiler tail is used as the deoxygenation heat source of the deaerator, and the saturated steam of the steam drum is used as the standby steam source for the deaerator. The deaerator is placed on the horizontal flue platform of the boiler, reducing the setting of the independent platform for the deaerator.
[0022] 5. The water-water heat exchanger is placed on the platform of the inlet header of the boiler economizer. By adjusting the water temperature and water flow at the inlet of the boiler economizer through a three-way valve, the low-temperature corrosion of the boiler economizer can be effectively avoided, the failure rate of the boiler equipment is reduced, and at the same time, it has a certain regulating effect on the boiler flue gas temperature.
[0023] 6. The use of the heat pipe heat exchanger can further reduce the boiler flue gas temperature, and the heat pipe heat exchanger has the characteristics of resistance to low-temperature corrosion. Its feed water is the feed water after thermal deoxygenation, extending the service life of the heat pipe heat exchanger. At the same time, once the heat pipe heat exchanger leaks due to low-temperature corrosion, it is also convenient to remove and replace through the connection structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:
[0025] Figure 1Schematic diagram of a waste heat boiler with deoxygenation, dust removal and denitrification functions according to an embodiment of the present invention;
[0026] Figure 2 Schematic diagram of the steam-water flow of the waste heat boiler according to an embodiment of the present invention;
[0027] Figure 3 Schematic diagram of the connection structure according to an embodiment of the present invention;
[0028] Figure 4 Schematic diagram of the sealing structure according to an embodiment of the present invention.
[0029] Explanation of reference numerals:
[0030] 1. Dust removal device; 2. Superheater; 2a. Superheater desuperheating device; 3. First-stage evaporator; 4. Denitrification device; 5. Steam drum; 6. Second-stage evaporator; 7. Evaporator for deaerator; 8. Economizer; 9. Heat pipe heat exchanger; 90. Flange plate; 91. First connecting pipe; 92. Second connecting pipe; 93. Locking screw; 94. Fixed nut; 95. Connecting sleeve; 96. Fixed sleeve; 97. Sealing rubber ring; 10. Three-way valve; 11. Deaerator; 12. Water-water heat exchanger; 13. Feed water pump. Detailed implementation manners
[0031] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.
[0032] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.
[0033] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood through specific circumstances.
[0034] The present utility model will be described in detail below with reference to the drawings and in conjunction with embodiments.
[0035] A waste heat boiler with deoxygenation, dust removal, and denitrification functions, as Figure 1 shown, includes a dust removal device 1, a denitrification device 4, a boiler body, a deaerator 11, a connection structure, a heat pipe heat exchanger 9, and a water-water heat exchanger 12; the dust removal device 1 is arranged at the flue gas inlet end of the boiler body, and the heat pipe heat exchanger 9 is detachably connected to the flue gas outlet end of the boiler body through the connection structure; a feed water pump 13 is provided at the water side inlet of the heat pipe heat exchanger 9, a three-way valve 10 is provided at the water side outlet of the heat pipe heat exchanger 9, one end of the three-way valve 10 is connected to the inlet of the water-water heat exchanger 12, and the other end of the three-way valve 10 is connected to the economizer 8 of the boiler body; the water outlet end of the deaerator 11 is connected to the heat pipe heat exchanger 9 through the feed water pump 13, and the water inlet end of the deaerator 11 is connected to the water outlet end of the water-water heat exchanger 12; the denitrification device 4 is arranged inside the boiler body. In this embodiment, the dust removal device 1 is a cyclone dust removal device. By adjusting the water inflow and temperature of the economizer 8 through the three-way valve 10, the outer wall temperature of the economizer 8 can be ensured to be higher than the flue gas acid dew point temperature, avoiding the low-temperature corrosion of the economizer; at the same time, by adjusting the water quantity and water temperature entering the economizer 8, the flue gas temperature level after the economizer 8 can also be adjusted, indirectly achieving the purpose of adjusting the boiler flue gas temperature.
[0036] The waste heat boiler has the functions of dust removal, denitrification, and deoxygenation, with a compact structure, small equipment floor area, few external flue gas pipelines, small equipment resistance, reduced overall equipment investment, greatly reduced temperature loss and resistance loss of the external flue gas and air pipelines, improved heat utilization efficiency, and reduced power consumption of the equipment; the boiler equipment has fewer failures. After the flue gas passes through dust removal, the fouling of the boiler heating surface is reduced, the heat transfer effect is improved, and it is not easy to block ash; after the flue gas passes through dust removal, it is beneficial to the efficient and stable operation of the denitrification equipment. The denitrification reactor is not easy to block ash, and the catalyst is not easy to fail due to ash blocking or poisoning, and can operate efficiently and stably for a long time.
[0037] The boiler body includes a boiler shell, a superheater 2, a superheater desuperheating device 2a, a first-stage evaporator 3, a steam drum 5, a second-stage evaporator 6, an evaporator for deaerator 7, and an economizer 8. The superheater 2, the superheater desuperheating device 2a, the first-stage evaporator 3, the steam drum 5, the second-stage evaporator 6, the evaporator for deaerator 7, and the economizer 8 are arranged in the boiler shell in sequence. The number of evaporator and economizer stages can be designed and determined according to the inlet flue gas parameters and the exhaust gas parameters of the boiler. One end of the boiler shell is a vertical flue, and the other end is a horizontal flue. The vertical flue is connected to the dust removal device 1, and the horizontal flue is connected to the heat pipe heat exchanger 9. The boiler shell is in an inverted "U" shape. The heating surface of the vertical flue is of a multi-tube box structure. The multiple tube box structures are stacked upward, and the multiple tube box structures are welded together. After the boiler is heated, it expands thermally upward as a whole. The deaerator 11 is placed above the platform of the heat pipe heat exchanger 9 and uses the saturated steam generated by the boiler evaporator for deaeration. The water-water heat exchanger 12 is placed at the inlet header platform of the economizer 8, and the inlet water temperature of the economizer 8 is adjusted by the three-way valve 10. The denitration device 4 is placed inside the boiler body. The main equipment is a denitration reactor, which uses a catalyst for denitration. The placement position of the denitration device can be adjusted according to the temperature level inside the boiler, and a region with a suitable working temperature level for the denitration catalyst is selected to place the denitration device. The heat source for the thermal deaeration of the deaerator is provided with saturated steam by a dedicated evaporator 7, which conforms to the cascade utilization of energy. At the same time, the operation mode of the deaerator is constant pressure / sliding pressure operation, and the deaeration temperature is guaranteed. The deaeration temperature is the saturated temperature. When the boiler load is low, the saturated steam of the steam drum can be used for deaeration, and the deaeration steam source is guaranteed.
[0038] The water-water heat exchanger 12 is provided with a water outlet and two water inlets. One water inlet is connected to the low-temperature feed water, and the other water inlet is connected to the three-way valve 10 through a pipeline. The water outlet is connected to the inlet header of the deaerator 11 and the economizer 8. The deaerator 11 is placed above the platform of the heat pipe heat exchanger 9, and the heat source for deaeration comes from the saturated steam of the outlet header of the evaporator for the deaerator. The water-water heat exchanger 12 is a mixing / surface heat exchanger with high heat transfer efficiency. It can reduce the temperature of the water entering the economizer 8, increase the heat transfer temperature difference between the flue gas side and the water side of the economizer 8, greatly improve the heat transfer efficiency, thereby significantly reducing the heat transfer area of the economizer 8, saving costs, and effectively reducing the boiler flue gas temperature. The water-water heat exchanger 12 has a low cost, small volume, small floor space, and is placed outside the furnace, without the risk of low-temperature corrosion. The water-water heat exchanger 12 can be used to heat the low-temperature feed water and then send it to the deaerator 11, reducing the consumption of saturated steam for deaeration. The superheater 2 is provided with a superheater desuperheating device 2a to prevent the steam temperature from exceeding the allowable temperature of the pipeline when the boiler flue gas temperature is too high. When the flue gas temperature is lower than 500 °C or there is no limit on the outlet temperature of the boiler superheater 2, the desuperheater can be not provided. The pipeline material of the superheater 2 can be selected as carbon steel or alloy steel according to the flue gas temperature level. The evaporator and the economizer can be selected as carbon steel or ND steel and other materials according to the flue gas composition conditions.
[0039] A special evaporator is used as the heat source for thermal deaeration. The deaerator 11 operates at constant pressure / variable pressure, with strong adaptability and in line with the cascade utilization of energy. The saturated steam generated by the evaporator on the low-temperature side of the boiler tail is used as the deaeration heat source of the deaerator 11, and the saturated steam of the steam drum 5 is used as the standby steam source for the deaerator 11. The deaerator 11 is placed on the platform of the boiler horizontal flue, reducing the setting of the independent platform for the deaerator 11. The utilization of the heat pipe heat exchanger 9 can further reduce the boiler flue gas temperature, and the heat pipe heat exchanger 9 has the characteristics of resistance to low-temperature corrosion. Its feed water is the feed water after thermal deaeration, extending the service life of the heat pipe heat exchanger 9. At the same time, once the heat pipe heat exchanger 9 leaks due to low-temperature corrosion, it is also convenient to remove and replace through the connection structure.
[0040] Such as Figures 3 - 4As shown, the connection structure includes a fixed sleeve 96, a connection sleeve 95, a first connecting pipe 91, a second connecting pipe 92, a sealing structure, two flange plates 90 and a plurality of locking structures. The two flange plates 90 are connected and fixed through the plurality of locking structures. One flange plate 90 is connected to the horizontal flue through the first connecting pipe 91, and the other flange plate 90 is connected to the heat pipe heat exchanger 9 through the second connecting pipe 92. The fixed sleeve 96 and the connection sleeve 95 are respectively fixedly connected to one flange plate 90. The connection sleeve 95 is arranged outside the fixed sleeve 96, and a sealing structure is arranged between the connection sleeve 95 and the fixed sleeve 96. The sealing structure includes a sealing groove and a plurality of sealing rubber rings 97. The sealing groove is arranged on the inner end face of the flange plate 90, and the sealing groove can cooperate with the end of the connection sleeve 95. The plurality of sealing rubber rings 97 are arranged in a row on the outer wall of the fixed sleeve 96. The locking structure includes a locking screw 93 and two fixing nuts 94. The locking screw 93 penetrates through the two flange plates 90, and the locking screw 93 is connected and fixed to the two flange plates 90 through the two fixing nuts 94.
[0041] The working mode of this example
[0042] The flue gas flow of the waste heat boiler: Flue gas inlet → Dust removal device 1 → Superheater 2 → First-stage evaporator 3 → Denitration device 4 → Second-stage evaporator 6 → Evaporator for deaerator 7 → Economizer 8 → Heat pipe heat exchanger 9 → Flue gas outlet. The denitration device 4 can adjust its position according to the level in the boiler furnace so that it is in a suitable catalyst working temperature range.
[0043] Steam-water flow of the waste heat boiler: The low-temperature feed water first enters the water-water heat exchanger 12 to exchange heat with the hot water from the heat pipe heat exchanger 9. After the water temperature rises, it enters the deaerator 11. The deaerated hot water enters the heat pipe heat exchanger 9 through the feed water pump 13. The water absorbs the heat of the flue gas in the heat pipe heat exchanger 9 and then is divided into two paths through the three-way valve 10 after the water temperature is raised. One path is used to heat the low-temperature feed water in the water-water heat exchanger 12; the other path enters the economizer 8. The inlet water of the economizer 8 consists of two parts. One part is the lower-temperature feed water at the outlet of the water-water heat exchanger 12, and the other part is the higher-temperature hot water heated by the heat pipe heat exchanger 9. The two parts of water are mixed and then enter the economizer 8. The water is heated by the economizer 8 and then enters the steam drum 5. The water in the steam drum 5 enters the first-stage evaporator 3, the second-stage evaporator 6, and the evaporator 7 for the deaerator 11 through the downcomer respectively. Among them, the steam-water mixtures of the first-stage evaporator 3 and the second-stage evaporator 6 enter the steam drum 5 through the riser, and the steam-water mixture of the evaporator 7 for the deaerator is used as the heating heat source of the deaerator 11. The saturated steam separated by the steam-liquid separator of the steam drum 5 enters the superheater 2 to form superheated steam meeting certain uses. The number of stages of the evaporator and the economizer 8 can be reasonably increased according to the flue gas parameters at the boiler inlet and the boiler floor height, etc. In addition, the water-water heat exchanger 12 can be reasonably increased according to the number of stages of the economizer 8. One stage of water-water heat exchanger 12 can be added between two stages of economizer 8. The added water-water heat exchanger 12 can achieve precise control of the water temperature at the inlet of the economizer 8 and achieve more refined adjustment of the boiler flue gas discharge temperature.
[0044] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A waste heat boiler with deoxygenation, dust removal and denitration functions, characterized in that: It includes a dust removal device (1), a denitration device (4), a boiler body, a deaerator (11), a connection structure, a heat pipe heat exchanger (9) and a water-water heat exchanger (12); The dust removal device (1) is arranged at the flue gas inlet end of the boiler body, and the heat pipe heat exchanger (9) is detachably connected to the flue gas outlet end of the boiler body through the connection structure; A feed water pump (13) is arranged at the water side inlet of the heat pipe heat exchanger (9), a three-way valve (10) is arranged at the water side outlet of the heat pipe heat exchanger (9), one end of the three-way valve (10) is connected to the inlet of the water-water heat exchanger (12), and the other end of the three-way valve (10) is connected to the economizer (8) of the boiler body; The water outlet end of the deaerator (11) is connected to the heat pipe heat exchanger (9) through a feed water pump (13), and the water inlet end of the deaerator (11) is connected to the water outlet end of the water-water heat exchanger (12); The denitration device (4) is arranged inside the boiler body.
2. The waste heat boiler with deoxidation, dust removal and denitration functions according to claim 1, characterized in that: The boiler body includes a boiler shell, a superheater (2), a superheater desuperheating device (2a), a first-stage evaporator (3), a steam drum (5), a second-stage evaporator (6), an evaporator for deaerator (7) and an economizer (8). The superheater (2), the superheater desuperheating device (2a), the first-stage evaporator (3), the steam drum (5), the second-stage evaporator (6), the evaporator for deaerator (7) and the economizer (8) are arranged in the boiler shell in sequence. One end of the boiler shell is a vertical flue, and the other end of the boiler shell is a horizontal flue. The vertical flue is connected to the dust removal device (1), and the horizontal flue is connected to the heat pipe heat exchanger (9). The boiler shell is in an inverted "U" shape. The heating surface of the vertical flue is of a multi-tube box structure. A plurality of the tube box structures are stacked upward, and welding is adopted between the plurality of tube box structures.
3. The waste heat boiler with deoxidation, dust removal and denitration functions according to claim 2, characterized in that: The water-water heat exchanger (12) is provided with a water outlet and two water inlets. One water inlet is connected to low-temperature feed water, and the other water inlet is connected to the three-way valve (10) through a pipeline. The water outlet is connected to the inlet header of the deaerator (11) and the economizer (8).
4. A waste heat boiler with deoxidation, dust removal and denitrification functions according to any one of claims 2 or 3, characterized in that: The connection structure includes a fixed sleeve (96), a connection sleeve (95), a first connecting pipe (91), a second connecting pipe (92), a sealing structure, two flange plates (90) and a plurality of locking structures. The two flange plates (90) are connected and fixed through the plurality of locking structures. One flange plate (90) is connected to the horizontal flue through the first connecting pipe (91), and the other flange plate (90) is connected to the heat pipe heat exchanger (9) through the second connecting pipe (92). The fixed sleeve (96) and the connection sleeve (95) are respectively fixedly connected to one flange plate (90). The connection sleeve (95) is arranged outside the fixed sleeve (96), and the sealing structure is arranged between the connection sleeve (95) and the fixed sleeve (96).
5. The waste heat boiler with deoxygenation, dust removal and denitration functions according to claim 4, characterized in that: The sealing structure includes a sealing groove and a plurality of sealing rubber rings (97). The sealing groove is arranged on the inner end face of the flange plate (90), and the sealing groove can cooperate with the end of the connecting sleeve (95). The plurality of sealing rubber rings (97) are arranged in a row on the outer wall of the fixed sleeve (96).
6. The waste heat boiler with deoxidation, dust removal and denitration functions according to claim 4, characterized in that: The locking structure includes a locking screw (93) and two fixing nuts (94). The locking screw (93) passes through the two flange plates (90), and the locking screw (93) is fixedly connected to the two flange plates (90) through the two fixing nuts (94).
7. The waste heat boiler with deoxygenation, dust removal and denitration functions according to claim 4, characterized in that: The dust removal device (1) is a cyclone dust removal device.