Boiler flue waste heat recovery equipment

Abstract

The invention discloses boiler flue waste heat recovery equipment in the technical field of boiler flue gas waste heat treatment, the boiler flue waste heat recovery equipment comprises a supporting frame, a recovery box, a chimney, a boiler and a flue, a first recovery assembly and a second recovery assembly are connected in the recovery box, the recovery box is connected to the top end of the supporting frame, and the flue is connected between the boiler and the recovery box; the top end of the flue is higher than the bottom end in the recycling box, the chimney communicates with the top of the recycling box, the first recycling assembly is located at the bottom of the second recycling assembly, and the first recycling assembly and the second recycling assembly are arranged in a staggered mode. Through staggered arrangement of the first recovery assembly and the second recovery assembly, the tortuosity of the flue gas flow channel is increased, the residence time of flue gas in the recovery box is prolonged, multi-stage gradient heat exchange is achieved, flue gas waste heat is fully absorbed stage by stage, and the heat recovery efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of boiler flue gas waste heat treatment, and in particular to a boiler flue waste heat recovery device. Background Art

[0002] In the field of boiler flue gas waste heat treatment technology, traditional boiler flue recovery equipment mainly uses a single flue gas recovery component to recover the waste heat of the flue gas discharged by the boiler. These devices usually include a supporting structure, a recovery box, a chimney, a boiler, a flue and a single flue gas recovery device. The flue gas is discharged from the boiler through the flue and enters the recovery device in the recovery box. The heat exchange medium (such as water or other fluids) in the recovery device absorbs the waste heat of the flue gas, and then the heat exchange medium is exported for other heating or heating needs.

[0003] Traditional boiler flue recovery equipment often only uses a single recovery component, which limits the efficiency and depth of waste heat recovery. Since the flue gas undergoes only one heat exchange in a single component, the large amount of heat energy it contains is often not fully utilized, resulting in low waste heat recovery efficiency. In a single recovery component, the flow of the heat exchange medium may be uneven, which will cause insufficient contact time between some flue gases and the heat exchange medium, thereby affecting the heat exchange efficiency. In addition, the uneven flow may also cause local overheating or cooling of the heat exchange medium, reducing the overall performance of the system. Summary of the invention

[0004] The present invention is intended to provide a method for solving the problem that the existing boiler flue waste heat recovery equipment recovers the flue gas only once during the recovery process, resulting in insufficient recovery and utilization of the flue gas waste heat.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a boiler flue waste heat recovery device, comprising a support frame, a recovery box, a chimney, a boiler, and a flue, wherein a first recovery component and a second recovery component are connected in the recovery box, the recovery box is connected to the top of the support frame, the flue is connected between the boiler and the recovery box, the top of the flue is higher than the bottom of the recovery box, the chimney is connected to the top of the recovery box, the first recovery component is located at the bottom of the second recovery component, and the first recovery component and the second recovery component are staggered.

[0006] Working principle of the present invention: When the boiler is running, high-temperature flue gas is generated, and the flue gas is transported to the recovery box through the flue. Since the flue is connected between the boiler and the recovery box, it provides a transmission channel for the flue gas. After arriving at the recovery box, the first recovery component and the second recovery component play a key role. The two components are internally staggered and the first recovery component is located at the bottom of the second recovery component. This layout changes the direction of the flue gas. When the flue gas rises, it needs to constantly change the path to bypass the internal recovery pipes of the two components, which prolongs the residence time in the recovery box.

[0007] In this process, the first recovery component and the second recovery component recover the heat from the flue gas respectively. The first recovery component exchanges heat with the flue gas through its internal circulating water pipe and transfers the heat to the circulating water; the second recovery component uses the hot water absorption pipe to transfer the heat in the flue gas to the water flowing in the pipe. These hot water will eventually flow into the insulation water tank and wait for the next operation of the boiler to flow into the boiler to realize heat recovery and reuse. After the heat exchange of the two-stage recovery components, the waste heat in the flue gas is fully absorbed and the temperature is reduced. Finally, the cooled flue gas is discharged from the equipment through the chimney connected to the top of the recovery tank, thus completing the entire process of heat recovery and flue gas emission.

[0008] Furthermore, the first recycling component includes a recycling rack and a circulating water pipe, the recycling rack includes a cardboard and a recycling plate, the recycling plate is connected to the side wall of the cardboard, the middle of the recycling plate is hollowed out, and the two opposite sides of the recycling plate are provided with a plurality of grooves, the circulating water pipe is curved and coiled in turn on the plurality of grooves of the recycling rack, one end of the circulating water pipe passes through the recycling box and is connected to the circulation inlet of the external insulation water tank, the other end of the circulating water pipe is connected to the circulation outlet of the external insulation water tank, and a circulating water pump is connected to the joint of the circulating water pipe and the external insulation water tank. By setting the circulating water pipe connected to the recycling rack, the length of the circulating water pipe in the recycling box is increased, the contact area between the circulating water pipe and the boiler flue gas is increased, and the heat exchange efficiency of the circulating water pipe is improved.

[0009] Furthermore, the second recovery component includes a recovery rack and a hot water absorption pipe, the hot water absorption pipe is bent and coiled in turn on a plurality of grooves of the recovery rack, one end of the hot water absorption pipe is connected to a tap water pipe, and the other end of the hot water absorption pipe is connected to an insulated water tank. The arrangement of the hot water absorption pipe and the recovery rack further improves the recovery rate of boiler flue gas.

[0010] Furthermore, there are multiple first recovery components and multiple second recovery components. Through the arrangement of multiple first recovery components and second recovery components, the boiler flue gas can undergo a sufficiently thorough heat exchange reaction.

[0011] Furthermore, the surfaces of the circulating water pipe and the hot water absorption pipe are both corrugated. Through the shape setting of the circulating water pipe and the hot water washing pipe, the contact area of ​​the boiler flue gas heat exchange is further increased, so that the boiler flue gas can undergo a large amount of heat exchange reaction at the same time.

[0012] Furthermore, the spacing between the grooves on the recovery plate is the same, and the grooves on the recovery plate of the first recovery component and the grooves on the recovery plate of the second recovery component are staggered. There is a certain distance gap between the multiple circulating water pipes and the hot water absorption pipe. This gap ensures the normal flow of waste heat gas. The waste heat gas enters the upper layer through this gap and contacts the circulating water pipe or the hot water absorption pipe. After the water pipe absorbs the waste heat, the waste heat gas is diverted and enters the upper layer. After mixing on both sides of the gap (the temperature of the mixed waste heat gas is uniform, which helps to improve the heat exchange efficiency in the later stage), it contacts the upper layer of circulating water pipe or the hot water absorption pipe. After the water pipe fully absorbs heat, it rushes into the upper layer through the gaps on both sides. In this way, the heat exchange is efficient, which can make the waste heat recovery equipment small in size, high in heat exchange efficiency, save production costs, and the waste heat flue gas discharges waste heat at a low level.

[0013] Furthermore, a filter plate is connected between the first component and the second component, and a filter screen is connected in the middle of the filter plate. Through the arrangement of the filter plate, fine particles remaining in the boiler flue gas can be blocked, so as to prevent the fine particles from being discharged with the boiler flue gas and causing air pollution.

[0014] Furthermore, the top of the flue is connected to a connection platform, the center of the connection platform is connected to a centralized pipe, and the centralized pipe connects the flue and the recovery box. Through the arrangement of the centralized pipe, the uneven flue gas discharged from the boiler can be re-aggregated and enter the recovery box more evenly.

[0015] Furthermore, a guide plate is connected between the centralized pipeline and the recovery box, and the guide plate is provided with a plurality of air guide holes, including convex air guide holes and concave water leakage holes. Through the arrangement of the guide plate, the boiler flue gas concentrated in the centralized pipeline can enter the recovery box evenly through the air guide holes on the guide plate, and through the arrangement of the convex air guide holes and the concave water leakage holes, the condensed water generated by the heat exchange reaction can be collected and discharged in a limited position.

[0016] Furthermore, the top of the recovery box is connected to a limit frame, the chimney is connected to the center of the limit frame, and the top of the flue is also connected to a guide plate. Through the setting of the limit frame, the chimney can be limited and protected to prevent the instantaneous discharge of boiler smoke from causing a certain impact on the chimney and causing damage to the chimney.

[0017] Beneficial effects of the present invention:

[0018] 1. The staggered arrangement of the first recovery component and the second recovery component not only increases the tortuosity of the flue gas flow path, prolongs the retention time of the flue gas in the recovery box, but also realizes multi-stage gradient heat exchange. Compared with the traditional single-layer recovery device, this design allows the flue gas waste heat to be fully absorbed step by step, and the heat recovery efficiency is increased by more than 30%. In addition, the staggered layout of the grooves effectively avoids the phenomenon of airflow short circuit, breaking through the technical bottleneck of heat saturation of a single component.

[0019] 2. The circulating water pipe and the hot water absorption pipe adopt a corrugated surface design, combined with the regular arrangement of the grooves of the recovery plate, to form a three-dimensional heat exchange network. The corrugated structure increases the effective contact area to more than 2.5 times that of traditional smooth pipes in the same space, while inducing turbulence effect, enhancing the heat transfer coefficient, and achieving "small volume, large capacity" efficient heat exchange, solving the problem of insufficient heat exchange caused by space limitations in traditional equipment.

[0020] 3. The innovative combination of raised and recessed water leakage holes in the guide plate not only achieves uniform distribution of flue gas, but also avoids water blockage through the self-flowing guide function of condensed water. This design automatically collects and guides condensed water when high-temperature flue gas contacts low-temperature water pipes, preventing internal corrosion of the equipment, extending service life and reducing maintenance costs.

[0021] 4. The filter plate adopts a detachable design, combined with the multi-layer filtration of the dislocated recovery component, the interception efficiency of particulate matter is more than 95%. In particular, through the synergistic effect of the guide plate at the bottom of the first recovery component and the filter screen at the bottom of the second component, a "coarse-fine" two-level filtration system is formed, which significantly reduces PM2.5 emissions while ensuring heat exchange efficiency.

[0022] 5. The linkage design of the centralized pipe and the guide plate can be dynamically adjusted according to the flue gas flow to ensure uniform airflow distribution. The design of the centralized pipe allows the uneven flue gas discharged from the boiler to be re-gathered and evenly enter the recovery box through the air guide holes on the guide plate. This design avoids local concentration of flue gas in the recovery box and ensures full contact between the flue gas and the heat exchange medium.

[0023] 6. The top of the flue is higher than the bottom of the recovery box. This design prevents the condensed water in the recovery box from flowing back into the flue. Since the recovery box will produce condensed water during the heat exchange process, if the top of the flue is lower than the bottom of the recovery box, the condensed water will easily accumulate and flow back into the flue, which may cause corrosion to the flue and boiler, shortening the service life of the flue and boiler. This design effectively eliminates this problem, ensures the normal operation of the flue, and reduces the cost of equipment maintenance and replacement. At the same time, this design helps to optimize the direction of flue gas flow, allowing the flue gas to flow more smoothly in the recovery box, further improving the contact effect between the flue gas and the recovery components, thereby improving the waste heat recovery efficiency.

[0024] 7. The external insulated water tank adopts a multi-layer insulation structure design, combined with a constant temperature control system, to reduce the temperature loss rate of the water tank to ≤1.5% per hour. Through the dynamic circulation mode of "hot water out and cold water in", cold water continuously flows into the recovery component to participate in heat exchange, forming a thermal energy closed loop. The data of the implementation example shows that the temperature of the insulated water tank only drops by 2-3°C at night, which significantly reduces the preheating energy consumption when the boiler is started the next day, and the comprehensive energy saving efficiency is improved by 15%-20%. In addition, the water tank and the circulating water pump are linked to ensure that the flow rate of the heat exchange medium (water) is dynamically matched with the boiler load to avoid energy loss caused by ineffective circulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a recovery box in a boiler flue waste heat recovery device of the present invention;

[0026] Figure 2 It is a structural schematic diagram of a boiler flue waste heat recovery device of the present invention;

[0027] Figure 3 for Figure 2 A top view of the mid-recovery rack;

[0028] Figure 4 for Figure 2 A schematic diagram of the structure of the connection between the middle recovery plate and the circulating water pipe;

[0029] Figure 5 for Figure 1 Front cross-sectional view of the intermediate circulating water pipe and the hot water absorption pipe;

[0030] Figure 6 for Figure 5 Flow path of the waste hot flue gas;

[0031] Figure 7 for Figure 2 Schematic diagram of the structure of the middle filter plate;

[0032] Figure 8 for Figure 1 Schematic diagram of the structure of the middle guide plate;

[0033] Fig. 9 for Figure 8 Schematic diagram of the structure of the raised air guide hole and the sunken water leakage hole. DETAILED DESCRIPTION

[0034] The following is further described in detail through specific implementation methods:

[0035] The figure marks in the drawings of the specification include: chimney 1, limit frame 2, recovery box 3, first recovery component 4, card plate 401, recovery plate 402, groove 403, handle 404, circulating water pipe 405, filter plate 5, filter screen 501, second recovery component 6, hot water absorption pipe 601, support frame 7, centralized pipeline 8, flue 9, boiler 10, connecting platform 11, guide plate 12.

[0036] The embodiment is basically as shown in the attached Figure 2 -Attached Figure 6 As shown: a boiler flue waste heat recovery device, including a support frame, a recovery box 3, a chimney 1, a boiler 10, a flue 9, a first recovery component 4 and a second recovery component 6, the recovery box 3 is fixedly connected to the top of the support frame, the front of the recovery box 3 is provided with a slot, the inner bottom of the recovery box 3 is provided with a drainage ditch around, one side of the drainage ditch is connected to the outside, the top of the recovery box 3 is fixedly connected to the limiting frame 2, the chimney 1 is fixedly connected to the center of the limiting frame 2, the chimney 1 is connected to the top of the recovery box 3, the flue 9 is connected between the boiler 10 and the recovery box 3, a flue 9 is provided with a flue gas temperature probe, and the top of the flue 9 is fixedly connected with a connection A platform 11 is connected with a centralized pipe 8 fixedly at the center of the connecting platform 11, and the centralized pipe 8 connects the flue 9 and the recovery box 3. A guide plate 12 inclined to the right is slidably connected between the centralized pipe 8 and the recovery box 3. The guide plates 1 are provided with air guide holes, which include raised air guide holes and recessed water leakage holes. The recessed water leakage holes are located on the right side of the bottom of the guide plate 12. The boiler 10 is located directly below the recovery box 3. The chimney 1 is connected to the top of the recovery box 3. The first recovery component 4 is located at the bottom of the second recovery component 6. A filter plate 5 is slidably connected between the first component and the second component, and a filter screen 501 is fixedly connected in the middle of the filter plate 5.

[0037] The first recycling component 4 includes two recycling racks and a circulating water pipe 405. The recycling rack includes a recycling plate 402 and two card plates 401. The recycling plate 402 is fixedly connected to the side wall between the two card plates 401. The outer wall of the outer card plate 401 is fixedly connected with a handle 404. The recycling plate 402 is slidably connected to the slot of the recycling box 3. The length of the recycling plate 402 is the same as the width of the recycling box 3. The middle of the recycling plate 402 is hollowed out. The left and right sides of the recycling plate 402 are provided with grooves 403. The spacing between the grooves 403 is the same. The circulating water pipe 405 is curved and coiled on the grooves 403 of the recycling rack in sequence. One end of the circulating water pipe 405 passes through the recycling box 3 and is connected to an external insulated water tank. The other end of the circulating water pipe 405 is connected to the other side of the external insulated water tank, and a water pump is fixedly connected to the joint of the circulating water pipe 405 and the external insulated water tank.

[0038] The second recovery component 6 includes two recovery racks and a hot water absorption pipe 601. The hot water absorption pipe 601 is curved and coiled in sequence on the groove 403 of the recovery rack. One end of the hot water absorption pipe 601 is fixedly connected to a tap water pipe, and the other end of the hot water absorption pipe 601 is fixedly connected to the boiler 10. The surfaces of the circulating water pipe 405 and the hot water absorption pipe 601 are both corrugated.

[0039] The four recovery plates 402 from bottom to top in the recovery box 3 have the same spacing, and the grooves 403 on adjacent recovery plates 402 are staggered.

[0040] The specific implementation process is as follows: the temperature of the flue 9 rises when the boiler 10 starts, the controller detects that the set temperature has been reached, and the water pump is started. The flue gas discharged from the boiler 10 will first pass through the flue 9 and reach the connecting platform 11 at the top of the flue 9. The central pipe 8 in the center of the connecting platform 11 will re-gather the uneven flue gas and allow it to enter the recovery box 3 more evenly. After entering the recovery box 3, the flue gas will pass through the first recovery component 4 and the second recovery component 6 in sequence. The first recovery component 4 is composed of a recovery rack and a circulating water pipe 405. The circulating water pipe 405 is coiled on the groove 403 of the recovery rack in a curved shape. One end of the circulating water pipe 405 is connected to the external insulation water tank, and the other end is connected to the other side of the water tank under the action of the water pump. The circulating water pipe 405 is fully in contact with the flue gas, absorbs a large amount of waste heat, and completes the initial heat exchange. After passing through the first recovery component 4, the flue gas continues to rise to the second recovery component 6. The second recovery component 6 also has a recovery rack, and the hot water absorption pipe 601 is coiled on it. One end of the hot water absorption pipe 601 is connected to the tap water pipe, and the other end leads to an external insulated water tank. When the flue gas passes through, the water in the hot water absorption pipe 601 absorbs the remaining waste heat and is heated. The hot water will enter the insulated water tank for standby, realizing secondary heat exchange. When the boiler 10 operates next time, the hot water at a certain temperature in the insulated water tank can be directly put into use. In addition, a filter plate 5 is provided between the first and second recovery components to intercept fine particles in the flue gas and prevent pollution. Finally, the treated low-temperature flue gas is discharged from the chimney 1. The whole process efficiently recovers the waste heat of the flue gas while taking environmental protection into consideration.

[0041] After using the above boiler flue waste heat recovery equipment for a period of time, the data obtained are as follows:

[0042]

[0043] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A boiler flue waste heat recovery device, comprising a support frame, a recovery box, a chimney, a boiler, and a flue, characterized in that: A first recovery component and a second recovery component are connected in the recovery box, the recovery box is connected to the top of the support frame, the flue is connected between the boiler and the recovery box, the top of the flue is higher than the bottom of the recovery box, the chimney is connected to the top of the recovery box, the first recovery component is located at the bottom of the second recovery component, and the first recovery component and the second recovery component are staggered.

2. A boiler flue waste heat recovery device according to claim 1, characterized in that: The first recycling component includes a recycling rack and a circulating water pipe, the recycling rack includes a cardboard and a recycling plate, the recycling plate is connected to the side wall of the cardboard, the middle of the recycling plate is hollowed out, and a plurality of grooves are arranged on opposite sides of the recycling plate. The circulating water pipe is curved and coiled in sequence on the plurality of grooves of the recycling rack, one end of the circulating water pipe passes through the recycling box and is connected to a circulating inlet of an external insulated water tank, the other end of the circulating water pipe is connected to a circulating outlet of the external insulated water tank, and a circulating water pump is connected to the joint between the circulating water pipe and the external insulated water tank.

3. The boiler flue waste heat recovery device according to claim 2, characterized in that: The second recovery component includes a recovery rack and a hot water absorption pipe, which is bent and coiled in turn on multiple grooves of the recovery rack. One end of the hot water absorption pipe is connected to a tap water pipe, and the other end of the hot water absorption pipe is connected to an insulated water tank.

4. The boiler flue waste heat recovery device according to claim 3, characterized in that: There are multiple first recycling components and multiple second recycling components.

5. The boiler flue waste heat recovery device according to claim 4, characterized in that: The surfaces of the circulating water pipe and the hot water absorbing pipe are both corrugated.

6. The boiler flue waste heat recovery device according to claim 5, characterized in that: The grooves on the recovery plate have the same spacing, and the grooves on the recovery plate of the first recovery component and the grooves on the recovery plate of the second recovery component are staggered.

7. The boiler flue waste heat recovery device according to claim 6, characterized in that: A filter plate is connected between the first component and the second component, and a filter screen is connected in the middle of the filter plate.

8. The boiler flue waste heat recovery device according to claim 7, characterized in that: The top of the flue is connected with a connecting platform, the center of the connecting platform is connected with a centralized pipeline, and the centralized pipeline connects the flue with the recovery box.

9. The boiler flue waste heat recovery device according to claim 8, characterized in that: A guide plate is connected between the centralized pipeline and the recovery box. The guide plate is provided with a plurality of air guide holes, including convex air guide holes and concave water leakage holes.

10. The boiler flue waste heat recovery device according to claim 9, characterized in that: The top of the recovery box is connected to a limiting frame, the chimney is connected to the center of the limiting frame, and the top of the flue is also connected to a guide plate.

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