Heat exchange device and waste heat recovery system
By employing multiple heat exchange tube sections and ash removal connecting pipe structures during the coking waste salt incineration acid production process, the problem of ash crystallization in the flue gas flow path was solved, enabling convenient cleaning and efficient cooling of the flue gas flow path.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA CITY ENVIRONMENT PROTECTION ENGINEERING LIMITED COMPANY
- Filing Date
- 2025-02-27
- Publication Date
- 2026-04-10
AI Technical Summary
During the process of burning coking waste salt to produce acid, when the sulfur-containing flue gas is cooled in the shell-and-tube heat exchanger, the fly ash carried in the flue gas is prone to crystallization, which leads to the formation of ash slag on the inner wall of the heat exchange tube, making it inconvenient to clean the flue gas flow path.
Multiple heat exchange tube sections are adopted, and adjacent flue gas flow sections are connected by a ash removal and connecting pipe structure to reduce the length of flue gas flow sections. Combined with the air flow section design, the cooling area is increased, and the generation and cleaning difficulty of ash and slag are reduced.
It effectively reduces the cleaning difficulty of flue gas flow path, improves flue gas cooling effect, and enables convenient cleaning of ash and slag through ash removal device, ensuring the normal operation of the system.
Smart Images
Figure CN224108680U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to acid making technology field, especially a kind of heat exchange device and waste heat recovery system. BACKGROUND
[0002] Coking waste salt incineration acid making is an important way for resource utilization of coking desulfurization waste liquid treatment, the process is by pretreatment to the sulfur-containing waste salt is incinerated, then the high-temperature sulfur-containing flue gas generated by waste salt incineration is reduced to 550 DEG C by waste heat boiler, and the sulfur-containing flue gas needs to be heat-exchanged and cooled by tube-shell heat exchanger, so that the temperature of sulfur-containing flue gas reaches the required sulfur-containing flue gas temperature of acid making unit.
[0003] When the sulfur-containing flue gas is heat-exchanged, the sulfur-containing flue gas flows and cools in the flue gas flow path section of the tube-shell heat exchanger, and a large amount of unburned fly ash is carried in the flue gas, including ammonium sulfate, ammonium thiosulfate, ammonium thiocyanate and sulfur, etc., the wall temperature of the flue gas flow path section is reduced, and the inner wall of the heat exchange tube is prone to crystallization, forming ash, which is inconvenient to clean. SUMMARY
[0004] The main purpose of the utility model is to provide a kind of heat exchange device and waste heat recovery system, to improve the problem that flue gas flow path section is inconvenient to clean.
[0005] To achieve the above-mentioned purpose, the heat exchange device provided by the utility model comprises:
[0006] A plurality of heat exchange pipe structure sections are arranged at intervals along the first direction and extend along the second direction, and a flue gas flow path section and an air flow path section capable of heat exchange are formed in each heat exchange pipe structure section;
[0007] An air flow pipe is used to connect the air flow path sections of two adjacent heat exchange pipe structure sections; and
[0008] A dust removal communication pipe structure is arranged at the corresponding end of two adjacent heat exchange pipe structure sections to communicate the flue gas flow path sections of the two adjacent heat exchange pipe structure sections.
[0009] In an embodiment, a dust removal nozzle is arranged on the dust removal communication pipe structure corresponding to the flue gas flow path section, and the dust removal nozzle is used for the dust removal device to extend into the flue gas flow path section and clean the inside of the flue gas flow path section.
[0010] In an embodiment, a plurality of flue gas flow path sections are formed in one heat exchange pipe structure section.
[0011] In an embodiment, the number of flue gas flow path sections in a plurality of heat exchange pipe structure sections gradually decreases along the first direction.
[0012] In an embodiment, the plurality of heat exchange pipe structure sections includes a head heat exchange pipe structure section, and the heat exchange device further comprises a flue gas inlet path section provided with a flue gas inlet, and each of the plurality of flue gas flow path sections in the head heat exchange pipe structure section is in communication with the flue gas inlet path section.
[0013] In an embodiment, the plurality of heat exchange pipe structure sections includes a tail heat exchange pipe structure section, and the heat exchange device further comprises a flue gas outlet path section provided with a flue gas outlet, and each of the plurality of flue gas flow path sections in the tail heat exchange pipe structure section is in communication with the flue gas outlet path section.
[0014] In an embodiment, the length of the flue gas flow path section in each of the plurality of heat exchange pipe structure sections gradually increases along a first direction.
[0015] The utility model also proposes a waste heat recovery system, including like heat exchange device, the heat exchange device includes:
[0016] A plurality of heat exchange pipe structure sections are arranged at intervals along a first direction and extend along a second direction, and a flue gas flow path section and an air flow path section capable of heat exchange are formed in each of the heat exchange pipe structure sections;
[0017] An air flow path pipe is used to connect the air flow path sections of two adjacent heat exchange pipe structure sections; and
[0018] A soot removal communication pipe structure is arranged at the corresponding end of two adjacent heat exchange pipe structure sections to communicate the flue gas flow path sections of the two adjacent heat exchange pipe structure sections.
[0019] In an embodiment, the plurality of heat exchange pipe structure sections includes a tail heat exchange pipe structure section, and the waste heat recovery system further comprises:
[0020] A waste incinerator having a combustion air inlet and a first flue gas outlet,
[0021] A waste heat boiler having a first flue gas inlet and a second flue gas outlet, the first flue gas inlet and the first flue gas outlet being in communication, and the first flue gas outlet and the first flue gas inlet being in communication; and
[0022] A combustion air fan, the air flow path section in the tail heat exchange pipe structure section has an air outlet in communication with the air inlet of the combustion air fan, and the air outlet of the combustion air fan is in communication with the combustion air inlet.
[0023] In an embodiment, the plurality of heat exchange pipe structure sections includes a tail heat exchange pipe structure section, and the waste heat recovery system further comprises:
[0024] An acid production section; and
[0025] The tail gas flow pipe is connected between the tail gas deacidification section and the acid making section, and has a temperature rising gas inlet.
[0026] The technical scheme of the utility model discloses a plurality of heat exchange pipe structure sections, and the smoke gas flow path sections of two adjacent heat exchange pipe structure sections are communicated through the ash removal communication pipe structure, so that the length of the smoke gas flow path section can be reduced, the cleaning length of the smoke gas flow path section can be reduced, the cleaning difficulty of the inside of the smoke gas flow path section can be reduced, and the cleaning inconvenience of the smoke gas flow path section as a whole can be improved. BRIEF DESCRIPTION OF DRAWINGS
[0027] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiment or the prior art description will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative labor.
[0028] Figure 1 The structure schematic view of the heat exchange device of an embodiment provided by the utility model is shown in the figure.
[0029] Figure 2 The structure schematic view of the heat exchange pipe structure section in the figure is shown in the figure. Figure 1
[0030] Figure 3 The structure schematic view of the waste heat recovery system provided by the utility model is shown in the figure.
[0031] EXPLANATION OF DRAWINGS:
[0032] 100, heat exchange device;1, heat exchange pipe structure section;11, smoke gas flow path section;12, air flow path section;121, cold air inlet;122, hot air outlet;2, air flow pipe;3, ash removal communication pipe structure;31, ash removal nozzle;32, first slag discharge port;4, smoke inlet section;41, smoke inlet;42, second slag discharge port;5, smoke outlet section;51, smoke outlet;52, third slag discharge port;
[0033] 200, waste heat recovery system;6, incinerator;61, combustion air inlet;62, first smoke outlet;63, fuel inlet;7, waste heat boiler;71, first smoke inlet;72, second smoke outlet;8, combustion air fan;9, acid making section;91, tail gas flow pipe;10, tail gas deacidification section;201, cold air motor.
[0034] The purposes, functional features and advantages of the utility model will be further explained in combination with embodiments with reference to the drawings. DETAILED DESCRIPTION
[0035] The technical solutions in the embodiments of the utility model will be clearly and completely described in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.
[0036] It should be noted that if the embodiments of the utility model involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.
[0037] In addition, if the embodiments of the utility model involve descriptions of "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one feature. In addition, "and / or" or "and / or" appearing throughout the text means that the three parallel schemes are included, for example, "A and / or B" includes A scheme, or B scheme, or A and B simultaneously satisfy the scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the utility model.
[0038] The coking waste salt incineration acid making is an important way for resource utilization of coking desulfurization waste liquid treatment, the process is through the pretreatment of the sulfur-containing waste salt, then the waste salt incineration produces high-temperature sulfur-containing flue gas, the temperature of the waste salt incineration is reduced to 550 DEG C through the waste heat boiler, and the sulfur-containing flue gas needs to be cooled through the tube and shell heat exchanger, so that the temperature of the sulfur-containing flue gas reaches the required sulfur-containing flue gas temperature of the acid making unit.
[0039] When the sulfur-containing flue gas is heat exchanged, the sulfur-containing flue gas flows in the flue gas flow path section of the shell-and-tube heat exchanger and is cooled, a large amount of unburned fly ash, including ammonium sulfate, ammonium thiosulfate, ammonium thiocyanate and sulfur, is carried in the flue gas, and crystallization is prone to occur at low temperature. The wall surface temperature of the flue gas flow path section is reduced, the inner wall surface of the heat exchange tube is prone to produce crystallization, forming ash slag, which is easy to block the flue gas flow path section, and the flue gas flow path section is inconvenient to clean.
[0040] The utility model provides a kind of heat exchange device.
[0041] Please refer to Figure 1 And Figure 2 In an embodiment of the utility model, the heat exchange device 100 includes:
[0042] A plurality of heat exchange tube structure sections 1 are arranged at intervals along a first direction and extend along a second direction, and a flue gas flow path section 11 and an air flow path section 12 capable of heat exchange are formed in each heat exchange tube structure section 1.
[0043] An air flow pipe 2 is used to connect the air flow path sections 12 of two adjacent heat exchange tube structure sections 1.
[0044] A dust removal communication pipe structure 3 is arranged at the corresponding end of two adjacent heat exchange tube structure sections 1 to communicate the flue gas flow path sections 11 of the two adjacent heat exchange tube structure sections 1.
[0045] The technical solution of the utility model reduces the length of the flue gas flow path section 11 and the cleaning length of the flue gas flow path section 11 by using a plurality of heat exchange tube structure sections 1 and communicating the flue gas flow path sections 11 of two adjacent heat exchange tube structure sections 1 through the dust removal communication pipe structure 3, thereby reducing the cleaning difficulty of the inside of the flue gas flow path section 11 and improving the cleaning inconvenience of the flue gas flow path section 11 as a whole.
[0046] The air flow path section 12 and the flue gas flow path section 11 are both straight pipes, the cross-sectional area of the air flow path section 12 is larger than the cross-sectional area of the flue gas flow path section 11, the flue gas flow path section 11 is arranged in the air flow path section 12, the two ends of the air flow path section 12 are closed, and the two ends of the flue gas flow path section 11 are open, which can reduce the direct contact between flue gas and air.
[0047] The first direction and the second direction intersect, and in the embodiment of the application, the first direction and the second direction are perpendicular.
[0048] Please refer to Figure 1 And Figure 2The heat exchange pipe structure section 1 includes a head heat exchange pipe structure section 1 and a tail heat exchange pipe structure section 1. The head heat exchange pipe structure section 1 is the first heat exchange pipe structure section 1 in the first direction, and the tail heat exchange pipe structure section 1 is the last heat exchange pipe structure section 1 in the first direction. The air flow path section 12 of the head heat exchange pipe structure section 1 is provided with a cold air inlet 121, and the air flow path section 12 of the tail heat exchange pipe structure section 1 is provided with a hot air outlet 122. External cold air flows from the cold air inlet 121 along the air flow path section, and the cold air is heated after heat exchange with the gas to form hot air, which can flow out of the hot air outlet 122.
[0049] When the number of heat exchange pipe structure sections 1 is two, the plurality of heat exchange pipe structure sections 1 only includes a head heat exchange pipe structure section 1 and a tail heat exchange pipe structure section 1. The flue gas and the cold air flow from the head heat exchange pipe structure section 1 to the tail heat exchange pipe structure section 1, and the head heat exchange pipe structure section 1 and the tail heat exchange pipe structure section 1 are arranged in sequence along the first direction.
[0050] When the number of heat exchange pipe structure sections 1 is three, four or more, the plurality of heat exchange pipe structure sections 1 includes a head heat exchange pipe structure section 1, a tail heat exchange pipe structure section 1 and a middle heat exchange pipe structure section 1. The middle heat exchange pipe structure section 1 is located between the head heat exchange pipe structure section 1 and the tail heat exchange pipe structure section 1, and the head heat exchange pipe structure section 1, the middle heat exchange pipe structure section 1 and the tail heat exchange pipe structure section 1 are arranged in sequence along the first direction.
[0051] In the embodiment, the number of heat exchange pipe structure sections 1 is two.
[0052] Please refer to Figure 1 and Figure 2 The flue gas flow path section 11 is formed in one heat exchange pipe structure section 1. The arrangement of the plurality of flue gas flow path sections 11 increases the cooling area of the flue gas and improves the cooling effect of the flue gas.
[0053] The soot cleaning communication pipe structure 3 is provided with a soot cleaning nozzle 31 corresponding to the flue gas flow path section 11. The soot cleaning nozzle 31 is used for the soot cleaning device to extend into the flue gas flow path section 11 and clean the inside of the flue gas flow path section 11. The common soot cleaning device includes a cleaning rod moving along the flue gas flow path section 11, and the cleaning rod is provided with a scraping structure. The soot cleaning nozzle 31 can be in and out of the cleaning rod, and the soot cleaning nozzle 31 remains sealed when the cleaning rod moves, which belongs to the conventional design in the field. When the cleaning rod moves along the flue gas flow path section 11, the scraping structure on the cleaning rod can scrape off the ash in the flue gas flow path section 11.
[0054] The end of the flue gas flow path section 11 penetrates into the ash removal communication pipe structure 3, the ash removal communication pipe structure 3 is provided with a first ash discharge port 32, and the ash in the flue gas flow path section 11 falls into the ash removal communication pipe structure 3, and then the ash can be conveniently discharged from the first ash discharge port 32 of the ash removal communication pipe structure 3.
[0055] By cleaning part of the flue gas flow path section 11 in one heat exchange pipe structure section 1 and keeping the flow of another part of the flue gas flow path section 11, the heat exchange of flue gas and the cleaning of ash in the flue gas flow path section 11 can be realized at the same time.
[0056] The number of the flue gas flow path sections 11 in the plurality of heat exchange pipe structure sections 1 gradually decreases along the first direction, that is, the number of the flue gas flow path sections 11 in the head heat exchange pipe structure section 1 is less than that in the tail heat exchange pipe structure section 1. The temperature of flue gas in the head heat exchange pipe structure section 1 is higher, and the temperature of cold air is lower, so the temperature difference between flue gas and cold air is relatively large. The heat exchange area of flue gas in the head heat exchange pipe structure section 1 is reduced, and the temperature reduction range of flue gas in the head heat exchange pipe structure section 1 is reduced, so as to reduce the number of ash generated in the flue gas flow path section 11 in the head heat exchange pipe structure section 1, and reduce the blockage generated in the flue gas flow path section 11 in the head heat exchange pipe structure section 1. The temperature of flue gas in the tail heat exchange pipe structure section 1 is relatively low, and the temperature of cold air after being heated is relatively high, so the temperature difference is relatively small. By increasing the number of flue gas flow path sections 11, the heat exchange area of flue gas is increased, and the cooling effect of flue gas is improved.
[0057] The length of the flue gas flow path section 11 in each of the plurality of heat exchange pipe structure sections gradually increases in the first direction. The length of the flue gas flow path section 11 in the first heat exchange pipe structure section 1 is less than the length of the flue gas flow path section 11 in the last heat exchange pipe structure section 1. The flue gas temperature in the first heat exchange pipe structure section 1 is relatively high, and the temperature of the cold air is relatively low, so the temperature difference between the flue gas and the cold air is relatively large. By reducing the heat exchange area of the flue gas in the first heat exchange pipe structure section 1, the temperature drop of the flue gas in the first heat exchange pipe structure section 1 is reduced, thereby reducing the amount of ash generated in the flue gas flow path section 11 in the first heat exchange pipe structure section 1 and reducing the blockage generated in the flue gas flow path section 11 in the first heat exchange pipe structure section 1. By reducing the length of the flue gas flow path section 11 in the first heat exchange pipe structure section 1, the difficulty of cleaning the flue gas flow path section 11 in the first heat exchange pipe structure section 1 is reduced, thereby reducing the frequency of cleaning the flue gas flow path section 11 in the first heat exchange pipe structure section 1. The flue gas temperature in the last heat exchange pipe structure section 1 is relatively low, and the temperature of the cold air after being heated is relatively high, so the temperature difference between the flue gas and the cold air is relatively small. By increasing the length of the flue gas flow path section 11 in the last heat exchange pipe structure section 1, the number of flue gas flow path sections 11 is increased, the heat exchange area of the flue gas is increased, the cooling effect of the flue gas is improved, and the amount of ash generated in the flue gas flow path section 11 in the last heat exchange pipe structure section 1 is increased.
[0058] Referring to Figure 1 and Figure 2 , the heat exchange device 100 further comprises a flue gas inlet path section 4, the flue gas inlet path section 4 is provided with a flue gas inlet 41, and the plurality of flue gas flow path sections 11 in the first heat exchange pipe structure section 1 are all in communication with the flue gas inlet path section 4. After the flue gas enters the flue gas inlet path section 4 through the flue gas inlet 41, the flue gas can flow into the plurality of flue gas flow path sections 11 respectively.
[0059] The flue gas inlet path section 4 is provided with a second ash discharge port 42. After the ash in the flue gas flow path section 11 is cleaned to the end of the flue gas flow path section 11 and falls into the flue gas inlet path section 4, the ash can be conveniently discharged from the second ash discharge port.
[0060] The heat exchange device 100 further comprises a flue gas outlet path section 5, the flue gas outlet path section 5 is provided with a flue gas outlet 51, and the plurality of flue gas flow path sections 11 in the last heat exchange pipe structure section 1 are all in communication with the flue gas outlet path section 5. The flue gas inlet path section 4 is provided with a third ash discharge port 52. After the ash in the flue gas flow path section 11 is cleaned to the end of the flue gas flow path section 11 and falls into the flue gas outlet path section 5, the ash can be conveniently discharged from the third ash discharge port 52.
[0061] The utility model discloses still propose a kind of waste heat recovery system 200, the waste heat recovery system 200 includes heat exchange device 100, the specific structure of the heat exchange device 100 refers to above-mentioned embodiment, since the waste heat recovery system 200 of the present application adopts all technical solutions of above-mentioned all embodiments, at least have all beneficial effects brought by the technical scheme of above-mentioned embodiment, here no longer repeat. Figure 1 And Figure 3 Wherein, the waste heat recovery system 200 further includes:
[0062] Incinerator 6 has combustion air inlet 61 and first smoke outlet 62,
[0063] Waste heat boiler 7 has first smoke inlet 7141 and second smoke outlet 72, the first smoke inlet 7141 and the first smoke outlet 62 are communicated, and the first smoke outlet 62 and the first smoke inlet 7141 are communicated.
[0064] Combustion air fan 8, the air flow path section 12 in the tail heat exchange pipe structural section 1 outlet and the combustion air fan motor air inlet are communicated, and the combustion air fan 8 outlet and the combustion air inlet 61 are communicated.
[0065] Please refer to Figure 1 And Figure 3 The air flow path section 12 in the tail heat exchange pipe structural section 1 outlet is hot air outlet 122, specifically, the hot air outlet 122 and the combustion air fan motor air inlet are communicated, and the air after heat exchange and temperature rise is sent into incinerator 6 by combustion air fan 8 and is used as combustion air, realizes the preheating of combustion air, and guarantees the combustion in the incinerator 6.
[0066] The incinerator 6 also has fuel inlet 63, the second smoke outlet 72 and the smoke inlet 41 are communicated, the waste heat boiler 7 is cooled to 550 DEG C and is sent into the smoke inlet path section 4, realizes the heat exchange cooling of flue gas, and the heat exchange device 100 is used to cool flue gas to 350 DEG C.
[0067] The waste heat recovery system 200 further includes:
[0068] Acid making section 9; and,
[0069] Tail gas deacidification section 10, the tail gas flow pipe 91 is connected between the tail gas deacidification section 10 and the acid making section 9, the tail gas flow pipe 91 has temperature rising gas inlet, and the air flow path section 12 in the tail heat exchange pipe structural section 1 outlet and the temperature rising gas inlet are communicated.
[0070] Specifically, the hot air outlet 122 is communicated with the temperature rising gas inlet, and the hot air after the heat exchange device 100 is heated is sent into the tail gas flow pipe 91, the tail gas in the tail gas flow pipe 91 is mixed and heated, and the utilization of the hot air generated by the heat exchange device 100 is improved.
[0071] Please refer to Figure 1 and Figure 3 The smoke outlet 51 is communicated with the smoke inlet 41 of the acid making section 9, the temperature of the smoke is reduced after passing through the acid making section 9, and the tail gas is formed; the temperature of the tail gas required by the tail gas deacidification section 10 is higher than that of the tail gas discharged by the acid making section 9, the tail gas and the hot air are mixed and heated, the requirement of the separate heating of the tail gas is reduced, the utilization of the hot air discharged by the heat exchange device 100 is realized, and the treatment of the tail gas by the tail gas deacidification section 10 is ensured.
[0072] The waste heat recovery system 200 further comprises a cold air machine 201, the air outlet of the cold air machine 201 is communicated with the cold air inlet 121, and the air inlet of the cold air machine 201 is exposed to the environment; starting the cold air machine 201 can send air into the air flow path section 12.
[0073] The above is only an exemplary embodiment of the present application, and does not limit the patent range of the present application, and any equivalent structural transformation or direct / indirect application in other related technical fields under the technical concept of the present application is included in the patent protection range of the present application.
Claims
1. A heat exchange device, characterized by, The heat exchange device comprises: a plurality of heat exchange pipe structure sections arranged at intervals along a first direction and extending along a second direction, each of the heat exchange pipe structure sections being formed with a flue gas flow path section and an air flow path section capable of heat exchange; an air flow pipe connecting the air flow path sections of two adjacent heat exchange pipe structure sections; and a soot blowing communication pipe structure arranged at the corresponding end portions of two adjacent heat exchange pipe structure sections to communicate the flue gas flow path sections of the two adjacent heat exchange pipe structure sections. The soot blowing communication pipe structure is provided with a soot blowing nozzle corresponding to the flue gas flow path section, and the soot blowing nozzle is used for the soot blowing device to extend into the flue gas flow path section and clean the inside of the flue gas flow path section.
2. The heat exchange device of claim 1, wherein The flue gas flow path section is formed in one of the heat exchange pipe structure sections.
3. The heat exchange device of claim 1, wherein The number of the flue gas flow path sections in the plurality of heat exchange pipe structure sections gradually decreases along the first direction.
4. The heat exchange device of claim 3, wherein The plurality of heat exchange pipe structure sections comprises a head heat exchange pipe structure section, and the heat exchange device further comprises a flue gas inlet path section provided with a flue gas inlet, and the plurality of flue gas flow path sections in the head heat exchange pipe structure section are all communicated with the flue gas inlet path section.
5. The heat exchange device of claim 3, wherein The plurality of heat exchange pipe structure sections comprises a tail heat exchange pipe structure section, and the heat exchange device further comprises a flue gas outlet path section provided with a flue gas outlet, and the plurality of flue gas flow path sections in the tail heat exchange pipe structure section are all communicated with the flue gas outlet path section.
6. The heat exchange device of claim 3, wherein The length of the flue gas flow path sections in the plurality of heat exchange pipe structure sections gradually increases along the first direction.
7. The heat exchange device of claim 1, wherein The heat exchange device comprises any one of claims 1 to 7.
8. A waste heat recovery system characterized by, The plurality of heat exchange pipe structure sections comprises a tail heat exchange pipe structure section, and the waste heat recovery system further comprises:
9. The waste heat recovery system of claim 8, wherein, a combustion furnace provided with a combustion air inlet and a first flue gas outlet, a waste heat boiler provided with a first flue gas inlet and a second flue gas outlet, the first flue gas inlet and the first flue gas outlet being communicated, and the first flue gas outlet and the first flue gas inlet being communicated; and a combustion air blower, an air outlet of the air flow path section in the tail heat exchange pipe structure section being communicated with an air inlet of the combustion air blower, and an air outlet of the combustion air blower being communicated with the combustion air inlet. The plurality of heat exchange pipe structure sections comprises a tail heat exchange pipe structure section, and the waste heat recovery system further comprises:
10. The heat recovery system of claim 8, wherein, an acid making section; and a tail gas deacidification section, and a tail gas flow pipe is connected between the tail gas deacidification section and the acid making section, the tail gas flow pipe being provided with a temperature rising gas inlet, and an air outlet of the air flow path section in the tail heat exchange pipe structure section being communicated with the temperature rising gas inlet.