Flue gas pipeline with waste heat recovery function

Abstract

The utility model relates to a flue gas pipeline with a waste heat recovery function, which belongs to the technical field of flue gas pipelines and comprises a flue gas input pipeline, a flue gas filtering box body, a waste heat recovery box body, a water storage tank and a flue gas output pipeline, and the flue gas input pipeline, the flue gas filtering box body, the waste heat recovery box body and the flue gas output pipeline are communicated in sequence. According to the utility model, the high-temperature-resistant filter assembly is arranged and can tolerate smoke at 900-1000 DEG C for a long time, the problem of failure of a traditional organic filter bag due to high-temperature fusion or metal filter bag oxidation can be avoided, and the dust removal treatment can be conveniently carried out on the filter assembly without shutdown by matching with a blowing dust removal system, so that the smoke passing rate is ensured; the heat exchange area can be effectively increased, so that the flue gas waste heat recovery rate is improved, the interception rate of flue gas impurities can be effectively increased through the multi-layer composite filtering structure, and the filtering effect is improved.

Description

Technical Field

[0001] This utility model relates to the field of flue gas duct technology, and in particular to a flue gas duct with waste heat recovery function. Background Technology

[0002] Boilers or other combustion systems generate a large amount of heat during operation, some of which is carried away by high-temperature flue gas and lost through the flue, resulting in heat loss and reducing the thermal efficiency of the combustion system. Waste heat recovery from flue gas ducts is an important measure to improve energy utilization efficiency, reduce energy consumption, and reduce carbon emissions.

[0003] A search revealed that Chinese patent CN202321041230.3 discloses an operation and maintenance structure with waste heat recovery function. The structure connects the exhaust pipe to the flue gas inlet pipe, allowing the flue gas to enter the flue gas purification box. The flue gas first passes through a dust filter to remove dust, and then is purified by the adsorption of activated carbon particles. This largely avoids the formation of carbon deposits in the flue gas pipe, which would otherwise thicken the pipe. The heat from the flue gas is transferred to the flue gas pipe and then heats the water in the waste heat recovery box, achieving effective heat recovery.

[0004] The above-mentioned technical solution has the following drawbacks. Although such flue gas duct structure is equipped with a filter structure to filter the flue gas and prevent it from polluting the duct and affecting the heat exchange effect, it is inconvenient to clean the filtered dust and impurities during actual use. To prevent dust accumulation on the filter layer from affecting the throughput and to ensure the flue gas emission effect, a flue gas duct with waste heat recovery function is proposed. It is equipped with a high-temperature resistant filter component that can withstand flue gas of 900-1000℃ for a long time, which can avoid the problem of traditional organic filter bags melting at high temperatures or metal filter bags oxidizing and failing. With the help of a jet cleaning system, the filter component can be cleaned without stopping the machine, thereby ensuring the flue gas throughput. The spiral finned tube heat exchanger can effectively increase the heat exchange area, thereby improving the waste heat recovery rate of the flue gas. The multi-layer composite filter structure can effectively improve the interception rate of flue gas impurities, thereby improving the filtration effect.

[0005] In view of this, this work improves and solves the above problems. Through dedicated research and application of theoretical principles, a technical solution with a reasonable design that can effectively improve the above defects has finally been proposed.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the general background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0007] This utility model provides a flue gas duct with waste heat recovery function, which can avoid the problems of traditional organic filter bags failing due to high temperature melting or metal filter bags oxidizing. It can facilitate the cleaning of filter components without stopping the machine, thereby ensuring the flue gas throughput. It can effectively increase the heat exchange area, thereby increasing the waste heat recovery rate of flue gas. Through the multi-layer composite filter structure, it can effectively increase the interception rate of flue gas impurities, thereby improving the filtration effect.

[0008] The present invention provides the following solution to the above-mentioned technical problems: A flue gas pipeline with waste heat recovery function includes a flue gas input pipeline, a flue gas filter box, a waste heat recovery box, a water storage tank, and a flue gas output pipeline. The flue gas input pipeline, the flue gas filter box, the waste heat recovery box, and the flue gas output pipeline are connected in sequence. A flue gas conveying channel is provided inside the flue gas filter box, and a primary metal filter screen and a metal fiber filter bag are installed in the flue gas conveying channel. A spiral finned tube heat exchanger is installed in the waste heat recovery box. The cooling medium of the water storage tank is pumped into the spiral finned tube heat exchanger. The spiral finned tube heat exchanger is connected to a heat energy utilization pipeline. A pulse jet cleaning pipe is provided in the flue gas filter box.

[0009] Based on the above technical solution, the present invention can be further improved as follows.

[0010] Furthermore, the flue gas filter box is equipped with a partition plate, which divides the flue gas filter box into a flue gas inlet chamber, a flue gas conveying chamber, and a flue gas outlet chamber. The partition plate divides the flue gas filter box into three chambers. The primary metal filter screen installed at the connection between the flue gas inlet chamber and the flue gas conveying chamber can filter large particulate impurities, while the metal fiber filter bag installed at the connection between the flue gas conveying chamber and the flue gas outlet chamber can filter micron-sized particles.

[0011] Furthermore, the partition plate is equipped with a filter bag grid corresponding to the metal fiber filter bag, and the partition plate has U-shaped holes corresponding to the primary metal filter screen and the metal fiber filter bag. The primary metal filter screen and the metal fiber filter bag can be installed on the partition plate by screws, so that the primary metal filter screen and the metal fiber filter bag can be easily and stably disassembled and assembled.

[0012] Furthermore, both the flue gas inlet chamber and the flue gas outlet chamber are equipped with differential pressure sensors. When the differential pressure sensors on both sides detect that the pressure difference between the flue gas inlet chamber and the flue gas outlet chamber is too large, it indicates that the primary metal filter screen and the metal fiber filter bag are clogged and need to be cleaned.

[0013] Furthermore, the flue gas filter box is equipped with an air tank, which is connected to an electromagnetic pulse valve. The electromagnetic pulse valve is connected to a pulse jet cleaning pipe, and the pulse jet cleaning pipe is uniformly connected to cleaning nozzles. Multiple sets of cleaning nozzles can respectively clean the primary metal filter screen and the metal fiber filter bag.

[0014] Furthermore, the flue gas filter box is equipped with a baffle plate, and the flue gas filter box is fixedly connected to a discharge hopper. There are two discharge hoppers, and each of the two discharge hoppers is fixedly connected to a rotary valve. Opening the rotary valve can discharge the filtered soot.

[0015] Furthermore, the water storage tank is fixedly connected to a water pump, and the water storage tank is connected to the spiral finned tube heat exchanger through the water pump, so that the water in the water storage tank can be pumped into the spiral finned tube heat exchanger.

[0016] Furthermore, the water storage tank is fixedly connected to a water supply pipeline, the water storage tank is equipped with an observation window, the water storage tank is connected to a discharge valve, and the observation window is equipped with a scale. Water can be supplied into the water storage tank through the water supply pipeline.

[0017] Furthermore, both the flue gas filtration box and the waste heat recovery box are equipped with sealed maintenance doors. By opening the sealed maintenance doors, the primary metal filter screen and metal fiber filter bag inside the flue gas filtration box and the waste heat recovery box can be disassembled and maintained.

[0018] This utility model provides a flue gas duct with waste heat recovery function, which has the following advantages:

[0019] 1. Made of 310S stainless steel, it can withstand flue gas at 900-1000℃ for a long time, avoiding the problem of traditional organic filter bags failing due to high temperature melting or metal filter bags oxidizing. With the pulse-jet cleaning system, the filter components can be cleaned without stopping the machine, thus ensuring the flue gas throughput.

[0020] 2. The water pump can transfer water from the storage tank to the spiral finned tube heat exchanger. The spiral finned tube heat exchanger has evenly arranged threaded heat dissipation fins on its outer wall, which can effectively increase the heat exchange area and thus improve the waste heat recovery rate of flue gas. The multi-layer composite filtration structure can effectively improve the interception rate of flue gas impurities, thereby improving the filtration effect.

[0021] 3. Differential pressure sensors are installed in the flue gas inlet chamber and the flue gas outlet chamber to detect the pressure difference. When the pressure difference exceeds 1200Pa, the electromagnetic pulse valve will be activated. The electromagnetic pulse valve can transmit the high-pressure air in the air tank to the pulse jet cleaning pipe. The cleaning nozzle can spray air to remove dust from the primary metal filter screen and metal fiber filter bag, and can also collect the cleaned dust. After opening the rotary valve, the collected dust and impurities can be discharged and cleaned.

[0022] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it according to the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. The specific implementation methods of this utility model are given in detail in the following embodiments and their accompanying drawings. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0024] Figure 1 A schematic diagram of a flue gas duct with waste heat recovery function provided in an embodiment of this utility model;

[0025] Figure 2 A front view of a flue gas duct with waste heat recovery function provided in an embodiment of this utility model;

[0026] Figure 3 A schematic diagram of the structure of a waste heat recovery box in a flue gas duct with waste heat recovery function provided in an embodiment of this utility model;

[0027] Figure 4 This is a schematic diagram of the structure of a U-shaped hole in a flue gas duct with waste heat recovery function, provided as an embodiment of the present invention.

[0028] The attached diagram lists the components represented by each number as follows:

[0029] 1. Flue gas inlet pipe; 2. Flue gas filter box; 3. Waste heat recovery box; 4. Water storage tank; 5. Flue gas outlet pipe; 6. Primary metal filter screen; 7. Metal fiber filter bag; 8. Spiral finned tube heat exchanger; 9. Heat energy utilization pipeline; 10. Divider plate; 11. Flue gas inlet chamber; 12. Flue gas conveying chamber; 13. Flue gas outlet chamber; 14. Pulse jet cleaning pipe; 15. Air manifold; 16. Electromagnetic pulse valve; 17. Cleaning nozzle; 18. Guide plate; 19. Discharge hopper; 20. Rotary valve; 21. Differential pressure sensor; 22. Water pump; 23. Water supply pipeline; 24. Observation window; 25. Sealed maintenance door; 26. Filter bag grid; 27. Discharge valve. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-4 The principles and features of this utility model are described below. The examples given are for illustrative purposes only and are not intended to limit the scope of this utility model. The utility model is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of this utility model will become clearer from the following description and claims. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this utility model.

[0031] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0033] like Figure 1-4 As shown, a flue gas pipeline with waste heat recovery function includes a flue gas input pipeline 1, a flue gas filter box 2, a waste heat recovery box 3, a water storage tank 4, and a flue gas output pipeline 5. The flue gas input pipeline 1, the flue gas filter box 2, the waste heat recovery box 3, and the flue gas output pipeline 5 are connected in sequence. A flue gas conveying channel is provided inside the flue gas filter box 2. The flue gas conveying channel is equipped with a primary metal filter screen 6 and a metal fiber filter bag 7. A spiral finned tube heat exchanger 8 is installed in the waste heat recovery box 3. The cooling medium of the water storage tank 4 is pumped into the spiral finned tube heat exchanger 8. The spiral finned tube heat exchanger 8 is connected to a heat energy utilization pipeline 9. A pulse jet cleaning pipe 14 is provided in the flue gas filter box 2.

[0034] Preferably, the flue gas filter box 2 is equipped with a partition plate 10. The flue gas filter box 2 is divided into a flue gas inlet chamber 11, a flue gas conveying chamber 12, and a flue gas outlet chamber 13 by the partition plate 10. The partition plate 10 divides the flue gas filter box 2 into three chambers. The primary metal filter screen 6 set at the connection between the flue gas inlet chamber 11 and the flue gas conveying chamber 12 can filter large particulate impurities, and the metal fiber filter bag 7 set at the connection between the flue gas conveying chamber 12 and the flue gas outlet chamber 13 can filter micron-sized particles.

[0035] Preferably, the partition plate 10 is equipped with a filter bag grid 26 corresponding to the metal fiber filter bag 7, and the partition plate 10 is provided with U-shaped holes corresponding to the primary metal filter screen 6 and the metal fiber filter bag 7. The primary metal filter screen 6 and the metal fiber filter bag 7 can be installed on the partition plate 10 by screws, so that the primary metal filter screen 6 and the metal fiber filter bag 7 can be easily and stably disassembled and assembled.

[0036] Preferably, both the flue gas inlet chamber 11 and the flue gas outlet chamber 13 are equipped with differential pressure sensors 21. When the differential pressure sensors 21 on both sides detect that the pressure difference between the flue gas inlet chamber 11 and the flue gas outlet chamber 13 is too large, it indicates that the primary metal filter screen 6 and the metal fiber filter bag 7 are clogged and need to be cleaned.

[0037] Preferably, the flue gas filter box 2 is equipped with an air manifold 15, the air manifold 15 is connected to an electromagnetic pulse valve 16, the electromagnetic pulse valve 16 is connected to a pulse jet cleaning pipe 14, and the pulse jet cleaning pipe 14 is uniformly connected to cleaning nozzles 17. Multiple sets of cleaning nozzles 17 can respectively clean the primary metal filter screen 6 and the metal fiber filter bag 7.

[0038] Preferably, the flue gas filter box 2 is equipped with a baffle plate 18, and the flue gas filter box 2 is fixedly connected to a discharge hopper 19. There are two discharge hoppers 19, and both discharge hoppers 19 are fixedly connected to a rotary valve 20. Opening the rotary valve 20 can discharge the filtered soot.

[0039] Preferably, the water storage tank 4 is fixedly connected to a water pump 22, and the water storage tank 4 is connected to the spiral finned tube heat exchanger 8 through the water pump 22. The water pump 22 can pump the water in the water storage tank 4 into the spiral finned tube heat exchanger 8.

[0040] Preferably, the water storage tank 4 is fixedly connected to a water supply pipe 23, the water storage tank 4 is provided with an observation window 24, the water storage tank 4 is connected to a discharge valve 27, and the observation window 24 is provided with a scale. Water can be supplied into the water storage tank 4 through the water supply pipe 23.

[0041] Preferably, both the flue gas filter box 2 and the waste heat recovery box 3 are equipped with sealed maintenance doors 25. By opening the sealed maintenance doors 25, the primary metal filter screen 6 and the metal fiber filter bag 7 inside the flue gas filter box 2 and the waste heat recovery box 3 can be disassembled and maintained.

[0042] The embodiments of this utility model are as follows:

[0043] Taking waste heat recovery from flue gas in a waste incineration plant as an example, the flue gas parameters are: temperature 450℃, dust concentration 30g / m³. 3 ,

[0044] Flue gas is introduced into the flue gas filter housing 2 through the flue gas inlet pipe 1. The flue gas then passes through the flue gas inlet chamber 11, the flue gas conveying chamber 12, the flue gas outlet chamber 13, and the waste heat recovery housing 3 before being discharged through the flue gas outlet pipe 5. The primary metal filter 6 filters large particles. Both the primary metal filter 6 and the metal fiber filter bag 7 are made of 310S stainless steel, capable of withstanding 900-1000℃ for long-term use and 1100℃ for short-term use. The metal fiber filter bag 7 within the filter bag grid 26 can filter micron-sized particles. The filtered high-temperature clean flue gas can be transferred to the waste heat recovery box 3. The water pump 22 can transfer the water in the water storage tank 4 to the spiral finned tube heat exchanger 8. The spiral finned tube heat exchanger 8 is uniformly provided with threaded heat dissipation fins on its outer wall. The flue gas can exchange heat with the water in the spiral finned tube heat exchanger 8, thereby heating the water. The heated water can be supplied to the external heating system to heat the plant area. The internal water level can be observed through the observation window 24. When the level is low, liquid can be added through the water supply pipe 23.

[0045] Differential pressure sensors 21 are installed in the flue gas inlet chamber 11 and the flue gas outlet chamber 13 to detect the differential pressure. When the differential pressure is large and exceeds 1200Pa, the electromagnetic pulse valve 16 is activated. The electromagnetic pulse valve 16 transmits the high-pressure air in the air tank 15 to the pulse jet cleaning pipe 14. The cleaning nozzle 17 sprays air to clean the primary metal filter screen 6 and the metal fiber filter bag 7. The pulse cleaning process lasts for ten seconds. The cleaned dust can be transferred to the discharge hopper 19. After opening the rotary valve 20, the collected dust and impurities can be discharged and cleaned. Every six months, the primary metal filter screen 6 and the metal fiber filter bag 7 can be removed, cleaned by ultrasonic cleaning, and reused.

[0046] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Those skilled in the art can readily implement this utility model based on the accompanying drawings and the above description. However, any modifications, alterations, or variations made by those skilled in the art without departing from the scope of the utility model's technical solution, utilizing the disclosed technical content, are equivalent embodiments of this utility model. Furthermore, any equivalent changes, alterations, or variations made to the above embodiments based on the essential technology of this utility model are still within the protection scope of this utility model's technical solution.

Claims

1. A flue gas duct with waste heat recovery function, comprising a flue gas inlet duct (1), a flue gas filter box (2), a waste heat recovery box (3), a water storage tank (4), and a flue gas outlet duct (5), characterized in that: The flue gas inlet pipe (1), flue gas filter box (2), waste heat recovery box (3), and flue gas outlet pipe (5) are connected in sequence. The flue gas filter box (2) is provided with a flue gas conveying channel. The flue gas conveying channel is equipped with a primary metal filter screen (6) and a metal fiber filter bag (7). The waste heat recovery box (3) is equipped with a spiral finned tube heat exchanger (8). The cooling medium of the water storage tank (4) is pumped into the spiral finned tube heat exchanger (8). The spiral finned tube heat exchanger (8) is connected to a heat energy utilization pipeline (9). The flue gas filter box (2) is provided with a pulse jet cleaning pipe (14).

2. The flue gas duct with waste heat recovery function according to claim 1, characterized in that, The flue gas filter box (2) is equipped with a partition plate (10), and the flue gas filter box (2) is divided into a flue gas inlet chamber (11), a flue gas conveying chamber (12), and a flue gas outlet chamber (13) by the partition plate (10).

3. The flue gas duct with waste heat recovery function according to claim 2, characterized in that, The partition plate (10) is equipped with a filter bag grid (26) corresponding to the metal fiber filter bag (7). The partition plate (10) has U-shaped holes corresponding to the primary metal filter screen (6) and the metal fiber filter bag (7). The primary metal filter screen (6) and the metal fiber filter bag (7) can be installed on the partition plate (10) by screws.

4. A flue gas duct with waste heat recovery function according to claim 2, characterized in that, Differential pressure sensors (21) are installed in both the flue gas inlet chamber (11) and the flue gas outlet chamber (13).

5. A flue gas duct with waste heat recovery function according to claim 1, characterized in that, The flue gas filter box (2) is equipped with an air bag (15), the air bag (15) is connected to an electromagnetic pulse valve (16), the electromagnetic pulse valve (16) is connected to a pulse jet cleaning pipe (14), and the pulse jet cleaning pipe (14) is uniformly connected to cleaning nozzles (17).

6. A flue gas duct with waste heat recovery function according to claim 1, characterized in that, The flue gas filter box (2) is equipped with a guide plate (18), and the flue gas filter box (2) is fixedly connected to a discharge hopper (19). There are two discharge hoppers (19), and both discharge hoppers (19) are fixedly connected to a rotary valve (20).

7. A flue gas duct with waste heat recovery function according to claim 1, characterized in that, The water storage tank (4) is fixedly connected to a water pump (22), and the water storage tank (4) is connected to the spiral finned tube heat exchanger (8) through the water pump (22).

8. A flue gas duct with waste heat recovery function according to claim 1, characterized in that, The water storage tank (4) is fixedly connected to a water supply pipeline (23), the water storage tank (4) is provided with an observation window (24), the water storage tank (4) is connected to a discharge valve (27), and the observation window (24) is provided with a scale.

9. A flue gas duct with waste heat recovery function according to claim 1, characterized in that, Both the flue gas filter box (2) and the waste heat recovery box (3) are equipped with sealed maintenance doors (25).

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