Boiler waste heat recovery device for thermal power plant

Abstract

The utility model relates to the technical field of thermal power generation, and particularly discloses a boiler waste heat recovery device for a thermal power plant, which comprises a boiler body, the upper end of the boiler body is communicated with a smoke outlet, the outer wall of the smoke outlet is fixedly connected with a support plate, and the upper side of the support plate is provided with a heat exchange mechanism. The heat exchange mechanism comprises a rectangular supporting frame fixedly connected to the upper end of the supporting plate, and the upper end of the rectangular supporting frame is fixedly connected with a first sealing gasket. Flue gas ascends layer by layer in the vertically-stacked flue gas pipeline with good heat conductivity, meanwhile, cooling water makes contact with the outer wall of the flue gas pipeline in the heat exchange box to absorb heat, through cooperation of a multi-stage heat exchange structure and a heat conduction material, flue gas waste heat is effectively recycled, and the energy utilization rate is remarkably increased; the filter bag can be quickly disassembled for cleaning or replacing without the assistance of tools, so that the aim of conveniently discharging and cleaning intercepted impurities is fulfilled.

Description

Technical Field

[0001] This utility model relates to the field of thermal power generation technology, and specifically discloses a waste heat recovery device for boilers in thermal power plants. Background Technology

[0002] Thermal power plants, as a crucial pillar of modern electricity supply, primarily convert chemical energy into electrical energy by burning fossil fuels such as coal, natural gas, and biomass, or by utilizing industrial waste. In this process, the boiler is the core equipment for converting fuel thermal energy into steam kinetic energy. It releases heat through fuel combustion, heats working fluids such as water or steam, and generates high-parameter steam (including specific pressure and temperature) that meets the operating requirements of the steam turbine.

[0003] In existing technologies, thermal power plants generally employ a thermal power generation model, relying on boilers to burn fuel to provide thermal energy. However, the large amount of flue gas generated after boiler combustion is often not integrated with waste heat recovery functions in existing devices and is usually directly filtered before being discharged. This treatment method results in the ineffective utilization of a significant amount of heat carried by the flue gas, leading to energy waste. Furthermore, since the filters are typically fixed inside the flue gas ducts with fasteners, the impurities trapped after filtration are difficult to remove and clean, requiring tools to disassemble the fasteners, making operation cumbersome. Therefore, a waste heat recovery device for boilers in thermal power plants is needed to solve the above problems. Utility Model Content

[0004] This utility model proposes a waste heat recovery device for boilers in thermal power plants, which can effectively recover heat from the flue gas of the boiler body, improve energy utilization, and at the same time clean the heat exchange box and flue gas pipes, and facilitate the discharge and cleaning of trapped impurities.

[0005] This utility model is implemented as follows: a waste heat recovery device for boilers in thermal power plants includes a boiler body, the upper end of which is connected to a flue gas outlet, a support plate is fixedly connected to the outer wall of the flue gas outlet, and a heat exchange mechanism is provided on the upper side of the support plate.

[0006] The heat exchange mechanism includes a rectangular support frame fixedly connected to the upper end of a support plate. A first sealing gasket is fixedly connected to the upper end of the rectangular support frame. Multiple heat exchange boxes distributed vertically are arranged on the upper side of the first sealing gasket. A second sealing gasket is fixedly connected to the upper end of each of the multiple heat exchange boxes. Multiple evenly distributed flue gas pipes are fixedly connected through the upper end of each of the multiple heat exchange boxes. A smoke collection hood that abuts against the uppermost second sealing gasket is arranged above the support plate.

[0007] The upper end of the support plate is fixedly connected to four L-shaped positioning plates. The four L-shaped positioning plates are respectively attached to the outer walls of multiple heat exchange boxes and the outer walls of the smoke collection hood. A connecting mechanism is provided on the outer side of the four L-shaped positioning plates.

[0008] The upper end of the smoke collection hood is connected to a first bend pipe, a second bend pipe is provided on the right side of the first bend pipe, and a filter mechanism is provided on the outside of the second bend pipe.

[0009] The filtration mechanism includes a fixing ring fixedly connected to the outer wall of the second bend, a threaded ring threadedly connected to the outer wall of the second bend, a sealing ring fixedly connected to the lower end of the fixing ring that abuts against the upper end of the threaded ring, and a filter bag fixedly connected to the lower end of the threaded ring.

[0010] As a preferred embodiment of the waste heat recovery device for boilers in thermal power plants according to this utility model, the connecting mechanism includes a first connecting frame that is fixedly connected to the outer wall of four L-shaped positioning plates. The outer wall of the first connecting frame is fixedly connected with a plurality of evenly distributed threaded sleeves. The outer wall of the smoke hood is fixedly connected with a second connecting frame. The outer wall of the second connecting frame is provided with a plurality of evenly distributed through holes. Bolts that are threaded into the plurality of threaded sleeves are inserted into the plurality of through holes.

[0011] As a preferred embodiment of the waste heat recovery device for boilers in thermal power plants according to this utility model, the rear ends of the plurality of heat exchange boxes are all connected to water inlet pipe joints, and the front ends of the plurality of heat exchange boxes are all connected to water outlet pipe joints.

[0012] As a preferred embodiment of the waste heat recovery device for boilers in thermal power plants according to this utility model, the first sealing gasket and the plurality of second sealing gaskets are all made of graphite cores and stainless steel strips, and the sealing ring is made of graphite cores and metal skeletons.

[0013] In a preferred embodiment of the waste heat recovery device for boilers in thermal power plants according to this utility model, the first bend and the second bend are connected by a flange.

[0014] As a preferred embodiment of the waste heat recovery device for boilers in thermal power plants according to this utility model, the support plate is fixedly connected to the boiler body with a plurality of evenly distributed reinforcing rods.

[0015] As a preferred embodiment of the waste heat recovery device for boilers in thermal power plants according to this utility model, the outer wall of the threaded ring is fixedly connected with multiple handles.

[0016] The beneficial effects of this utility model are:

[0017] 1. Flue gas rises layer by layer in a vertically stacked flue gas duct with good thermal conductivity. At the same time, cooling water absorbs heat by contacting the outer wall of the flue gas duct in the heat exchange box. Through the combination of multi-stage heat exchange structure and heat-conducting materials, the waste heat of flue gas is effectively recovered, significantly improving energy utilization.

[0018] 2. By untying the connection and fixation of the smoke hood, the heat exchange box can be separated layer by layer, thereby performing a comprehensive physical cleaning of the outer wall of the heat exchange box and the inner wall of the flue gas duct.

[0019] 3. Since the rotating threaded ring is connected to the second bend in the threaded connection, the filter bag can be quickly disassembled for cleaning or replacement without the need for tools, thus facilitating the discharge and cleaning of trapped impurities. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0021] Figure 1 This is a front sectional view of the overall structure of a waste heat recovery device for a boiler in a thermal power plant according to the present invention.

[0022] Figure 2 For the present utility model Figure 1 Enlarged view of point A in the middle;

[0023] Figure 3 This is a partial structural diagram of the present invention;

[0024] Figure 4 This is a partial structural diagram of the present invention.

[0025] The markings in the diagram are: 1. Boiler body; 2. Flue gas outlet; 3. Support plate; 4. L-shaped positioning plate; 5. Rectangular support frame; 6. First sealing gasket; 7. Heat exchange box; 8. Second sealing gasket; 9. Flue gas duct; 10. Inlet water pipe joint; 11. Outlet water pipe joint; 12. Smoke hood; 13. First connecting frame; 14. Threaded sleeve; 15. Second connecting frame; 16. Through hole; 17. Bolt; 18. First bend; 19. Second bend; 20. Fixing ring; 21. Threaded ring; 22. Sealing ring; 23. Filter bag; 24. Reinforcing rod. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments to aid in understanding its content. Unless otherwise specified, the methods used in this invention are conventional methods; the raw materials and apparatus used, unless otherwise specified, are conventional commercially available products.

[0027] Please see Figure 1-4A waste heat recovery device for boilers in thermal power plants includes a boiler body 1, with a flue gas outlet 2 connected to the upper end of the boiler body 1, a support plate 3 fixedly connected to the outer wall of the flue gas outlet 2, and a heat exchange mechanism provided on the upper side of the support plate 3.

[0028] The heat exchange mechanism includes a rectangular support frame 5 fixedly connected to the upper end of the support plate 3. A first sealing gasket 6 is fixedly connected to the upper end of the rectangular support frame 5. Multiple heat exchange boxes 7 are arranged vertically on the upper side of the first sealing gasket 6. A second sealing gasket 8 is fixedly connected to the upper end of each of the multiple heat exchange boxes 7. Multiple evenly distributed flue gas pipes 9 are fixedly connected through the upper end of each of the multiple heat exchange boxes 7. A smoke collection hood 12 is arranged above the support plate 3, which abuts against the uppermost second sealing gasket 8.

[0029] Four L-shaped positioning plates 4 are fixedly connected to the upper end of the support plate 3. The four L-shaped positioning plates 4 are respectively attached to the outer walls of multiple heat exchange boxes 7 and the outer walls of the smoke hood 12. A connecting mechanism is provided on the outer side of the four L-shaped positioning plates 4.

[0030] The upper end of the smoke collection hood 12 is connected to a first bend pipe 18, a second bend pipe 19 is provided on the right side of the first bend pipe 18, and a filter mechanism is provided on the outside of the second bend pipe 19.

[0031] The filtration mechanism includes a fixing ring 20 fixedly connected to the outer wall of the second bend 19, a threaded ring 21 threadedly connected to the outer wall of the second bend 19, a sealing ring 22 fixedly connected to the lower end of the fixing ring 20 and abutting against the upper end of the threaded ring 21, and a filter bag 23 fixedly connected to the lower end of the threaded ring 21.

[0032] In this embodiment: the rectangular support frame 5 and the bottom heat exchange box 7 are sealed by the first sealing gasket 6 to prevent flue gas leakage. Multiple heat exchange boxes 7 are stacked sequentially by the second sealing gasket 8 to form a multi-stage heat exchange structure. The smoke hood 12 abuts against the uppermost second sealing gasket 8 to prevent flue gas leakage. The connecting mechanism continuously applies downward pressure to the smoke hood 12 to ensure that the first sealing gasket 6 and the second sealing gasket 8 are squeezed tightly. The installation positions of the multiple heat exchange boxes 7 and the smoke hood 12 are accurately positioned by four L-shaped positioning plates 4.

[0033] During heat exchange, the high-temperature flue gas generated by the combustion of fuel in the boiler body 1 is discharged through the flue gas outlet 2 and enters the heat exchange mechanism through the rectangular support frame 5 above the support plate 3. The flue gas first enters the multiple flue gas pipes 9 of the lowest heat exchange box 7 and flows upward, passing through the flue gas pipes 9 of each heat exchange box 7 step by step, and finally collects at the smoke collection hood 12. Cooling water enters the heat exchange box 7 through the water inlet pipe joint 10, contacts the outer wall of the flue gas pipe 9 inside the box, absorbs the heat of the flue gas and its temperature rises, and then is discharged through the water outlet pipe joint 11 to achieve heat recovery. The flue gas pipe 9 and the heat exchange box 7 have good thermal conductivity, and with the multi-stage heat exchange method, the heat exchange effect can be improved. In this way, the heat in the flue gas of the boiler body 1 can be effectively recovered, and the energy utilization rate can be improved.

[0034] After heat exchange, the temperature of the flue gas decreases and enters the first bend pipe 18 through the smoke collection hood 12, and then enters the filter mechanism through the second bend pipe 19. In the filter mechanism, the second bend pipe 19 is connected to the threaded ring 21 by threads, and the sealing ring 22 between the two ensures airtightness. When the flue gas passes through the filter bag 23, dust and other impurities are intercepted and the purified flue gas is discharged.

[0035] When cleaning the heat exchange box 7 and the flue gas duct 9, the restriction on the smoke collection hood 12 is released through the connecting mechanism, and the smoke collection hood 12 can be separated from the heat exchange box 7. The heat exchange box 7 can be removed layer by layer, and then the outer wall of the heat exchange box 7 and the inner wall of the flue gas duct 9 can be cleaned with tools. In this way, the purpose of cleaning the heat exchange box 7 and the flue gas duct 9 can be achieved.

[0036] When cleaning or replacing the filter bag 23, rotate the threaded ring 21 to separate it from the second bend 19, and the filter bag 23 can be quickly disassembled for cleaning or replacement. At the same time, the impurities collected inside the filter bag 23 can be discharged without the need for tools, thus facilitating the discharge and cleaning of trapped impurities. The filter bag 23 is made of polytetrafluoroethylene, which has excellent high temperature resistance.

[0037] As a technical optimization of this utility model, the connecting mechanism includes a first connecting frame 13 that is fixedly connected to the outer wall of four L-shaped positioning plates 4. The outer wall of the first connecting frame 13 is fixedly connected to a plurality of evenly distributed threaded sleeves 14. The outer wall of the smoke hood 12 is fixedly connected to a second connecting frame 15. The outer wall of the second connecting frame 15 is provided with a plurality of evenly distributed through holes 16. Bolts 17 that are threaded into the interior of the plurality of threaded sleeves 14 are inserted into the interior of the plurality of through holes 16.

[0038] In this embodiment: the bolt 17 is inserted through the hole 16 and screwed into the inside of the threaded sleeve 14. The bolt 17 applies downward pressure to the second connecting frame 15, and then the second connecting frame 15 continuously applies downward clamping force to the smoke hood 12, ensuring that the first sealing gasket 6 and the second sealing gasket 8 are squeezed tightly.

[0039] As a technical optimization of this utility model, the rear ends of multiple heat exchange boxes 7 are all connected to water inlet pipe joints 10, and the front ends of multiple heat exchange boxes 7 are all connected to water outlet pipe joints 11.

[0040] In this embodiment: by setting multiple inlet pipe joints 10, it is convenient to connect to the external water inlet pipe; by setting multiple outlet pipe joints 11, it is convenient to connect to the external water outlet pipe.

[0041] As a technical optimization of this utility model, the first sealing gasket 6 and the multiple second sealing gaskets 8 are all made of graphite core and stainless steel strip, and the sealing ring 22 is made of graphite core and metal skeleton.

[0042] In this embodiment: the first sealing gasket 6 and the second sealing gasket 8 are made of graphite core and stainless steel strip, which have the characteristics of high temperature resistance and can adapt to high temperature environment. The sealing ring 22 is made of graphite core and metal skeleton, which can prevent the sealing ring 22 from failing during use.

[0043] As a technical optimization of this utility model, the first bend 18 and the second bend 19 are connected by a flange.

[0044] In this embodiment, the first bend 18 and the second bend 19 are connected by a flange, which facilitates the connection and fixation of the first bend 18 and the second bend 19.

[0045] As a technical optimization of this utility model, a plurality of evenly distributed reinforcing rods 24 are fixedly connected between the support plate 3 and the boiler body 1.

[0046] In this embodiment, multiple reinforcing rods 24 are provided to improve the stability of the connection to the support plate 3.

[0047] As a technical optimization of this utility model, the outer wall of the threaded ring 21 is fixedly connected with multiple handles.

[0048] In this embodiment, multiple handles are provided to facilitate manual rotation of the threaded ring 21.

[0049] The working principle and usage process of this utility model are as follows: The rectangular support frame 5 and the bottom heat exchange box 7 are sealed by the first sealing gasket 6 to prevent flue gas leakage. Multiple heat exchange boxes 7 are stacked in sequence by the second sealing gasket 8 to form a multi-stage heat exchange structure. The smoke hood 12 abuts against the uppermost second sealing gasket 8 to prevent flue gas leakage. Multiple bolts 17 are respectively engaged with multiple threaded sleeves 14. The second connecting frame 15 continuously applies downward pressure to the smoke hood 12 to ensure that the first sealing gasket 6 and the second sealing gasket 8 are squeezed tightly. The installation positions of the multiple heat exchange boxes 7 and the smoke hood 12 are accurately positioned by four L-shaped positioning plates 4.

[0050] During heat exchange, the high-temperature flue gas generated by the combustion of fuel in the boiler body 1 is discharged through the flue gas outlet 2 and enters the heat exchange mechanism through the rectangular support frame 5 above the support plate 3. The flue gas first enters the multiple flue gas pipes 9 of the lowest heat exchange box 7 and flows upward, passing through the flue gas pipes 9 of each heat exchange box 7 step by step, and finally collects at the smoke collection hood 12. Cooling water enters the heat exchange box 7 through the water inlet pipe joint 10, contacts the outer wall of the flue gas pipe 9 inside the box, absorbs the heat of the flue gas and its temperature rises, and then is discharged through the water outlet pipe joint 11 to achieve heat recovery. The flue gas pipe 9 and the heat exchange box 7 have good thermal conductivity, and with the multi-stage heat exchange method, the heat exchange effect can be improved. In this way, the heat in the flue gas of the boiler body 1 can be effectively recovered, and the energy utilization rate can be improved.

[0051] The first sealing gasket 6 and the second sealing gasket 8 are made of graphite core and stainless steel strip, which have the characteristics of high temperature resistance and can adapt to high temperature environment.

[0052] After heat exchange, the temperature of the flue gas decreases and enters the first bend pipe 18 through the smoke collection hood 12, and then enters the filter mechanism through the second bend pipe 19. In the filter mechanism, the second bend pipe 19 is connected to the threaded ring 21 by threads, and the sealing ring 22 between the two ensures airtightness. When the flue gas passes through the filter bag 23, dust and other impurities are intercepted and the purified flue gas is discharged.

[0053] When cleaning the heat exchange box 7 and the flue gas duct 9, loosen the bolts 17 of the connecting mechanism to separate the smoke hood 12 from the heat exchange box 7, remove the heat exchange box 7 layer by layer, and then clean the outer wall of the heat exchange box 7 and the inner wall of the flue gas duct 9 with tools. In this way, the purpose of cleaning the heat exchange box 7 and the flue gas duct 9 can be achieved.

[0054] When cleaning or replacing the filter bag 23, rotate the handle on the outer wall of the threaded ring 21 to separate it from the fixing ring 20, and the filter bag 23 can be quickly disassembled for cleaning or replacement. At the same time, the impurities collected inside the filter bag 23 can be discharged without the need for tools, thus facilitating the discharge and cleaning of trapped impurities. The filter bag 23 is made of polytetrafluoroethylene, which has excellent high temperature resistance.

[0055] In the description of this utility model, it should be understood that the terms "left", "right", "up", "down", "top", "bottom", "front", "back", "inner", "outer", "back", "middle", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0056] However, the above description is only a specific embodiment of this utility model and should not be construed as limiting the scope of implementation of this utility model. Therefore, any substitution of equivalent components or equivalent changes and modifications made in accordance with the scope of protection of this utility model should still fall within the scope of the claims of this utility model.

Claims

1. A waste heat recovery device for a boiler in a thermal power plant, comprising a boiler body (1), characterized in that: The upper end of the boiler body (1) is connected to a flue gas outlet (2), and a support plate (3) is fixedly connected to the outer wall of the flue gas outlet (2). A heat exchange mechanism is provided on the upper side of the support plate (3). The heat exchange mechanism includes a rectangular support frame (5) fixedly connected to the upper end of the support plate (3). A first sealing gasket (6) is fixedly connected to the upper end of the rectangular support frame (5). Multiple heat exchange boxes (7) are arranged vertically on the upper side of the first sealing gasket (6). A second sealing gasket (8) is fixedly connected to the upper end of each of the multiple heat exchange boxes (7). Multiple uniformly distributed flue gas pipes (9) are fixedly connected through the upper end of each of the multiple heat exchange boxes (7). A smoke collection hood (12) is arranged above the support plate (3) and abuts against the uppermost second sealing gasket (8). The upper end of the support plate (3) is fixedly connected with four L-shaped positioning plates (4). The four L-shaped positioning plates (4) are respectively attached to the outer wall of the multiple heat exchange boxes (7) and the outer wall of the smoke hood (12). A connecting mechanism is provided on the outer side of the four L-shaped positioning plates (4). The upper end of the smoke collection hood (12) is connected to a first bend (18), a second bend (19) is provided on the right side of the first bend (18), and a filter mechanism is provided on the outside of the second bend (19). The filtration mechanism includes a fixing ring (20) fixedly connected to the outer wall of the second bend (19), a threaded ring (21) threadedly connected to the outer wall of the second bend (19), a sealing ring (22) fixedly connected to the lower end of the fixing ring (20) and abutting against the upper end of the threaded ring (21), and a filter bag (23) fixedly connected to the lower end of the threaded ring (21).

2. The waste heat recovery device for boilers in thermal power plants according to claim 1, characterized in that: The connecting mechanism includes a first connecting frame (13) that is fixedly connected to the outer wall of four L-shaped positioning plates (4). The outer wall of the first connecting frame (13) is fixedly connected with a plurality of evenly distributed threaded sleeves (14). The outer wall of the smoke hood (12) is fixedly connected with a second connecting frame (15). The outer wall of the second connecting frame (15) is provided with a plurality of evenly distributed through holes (16). Bolts (17) that are threaded into the interior of the plurality of through holes (16) are inserted into the interior of the plurality of threaded sleeves (14).

3. The waste heat recovery device for boilers in thermal power plants according to claim 1, characterized in that: The rear end of each of the heat exchange boxes (7) is connected to an inlet pipe joint (10), and the front end of each of the heat exchange boxes (7) is connected to an outlet pipe joint (11).

4. The waste heat recovery device for boilers in thermal power plants according to claim 1, characterized in that: The first sealing gasket (6) and the plurality of second sealing gaskets (8) are made of graphite core and stainless steel strip, and the sealing ring (22) is made of graphite core and metal skeleton.

5. A waste heat recovery device for boilers in thermal power plants according to claim 1, characterized in that: The first bend (18) and the second bend (19) are connected by a flange.

6. The waste heat recovery device for boilers in thermal power plants according to claim 1, characterized in that: The support plate (3) is fixedly connected to the boiler body (1) by a number of evenly distributed reinforcing rods (24).

7. A waste heat recovery device for boilers in thermal power plants according to claim 1, characterized in that: The outer wall of the threaded ring (21) is fixedly connected with multiple handles.

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