Boiler system and dry quenching system
By adopting composite circulation technology in the dry quenching boiler system and circulating unsaturated media back to the mixer using the recirculation unit, the problem that the working fluid cannot effectively absorb heat during low-load operation is solved, and efficient operation under different working conditions is achieved and the risk of explosive pipes is reduced.
Patent Information
- Application Number
- CN202421790048.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-26
- Publication Date
- 2025-06-10
- Estimated Expiration
- 2034-07-26
AI Technical Summary
When the dry coke quenching boiler is running at low load, the working fluid cannot effectively absorb the heat in the dry coke quenching circulating gas, resulting in the temperature of the circulating gas being too high, increasing the risk of pipeline corrosion and the probability of pipe bursting.
A boiler system adopts a composite cycle, including a DC unit and a recirculation unit. The recirculation unit circulates the unsaturated medium and part of the saturated medium back to the mixer through the first forced circulation pump, mixes with the medium heated by the economizer, and enters the evaporator and the water-cooled wall again to achieve further absorption of heat.
It can generate sufficient superheated steam under different operating conditions, which improves the working efficiency of the boiler system, reduces the risk of pipeline corrosion and pipe bursting, and reduces energy loss during low-load operation.
Smart Images
Figure CN222961365U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of coke dry quenching, and in particular to a boiler system and a coke dry quenching system. Background Art
[0002] The dry coke quenching technology has been widely used by enterprises because it is superior to wet coke quenching in energy saving, environmental protection and improving coke quality. Domestic dry coke quenching technology has become increasingly mature. At present, the dry coke quenching boiler adopts the natural circulation method. When running at low load, the working fluid cannot absorb the heat in the dry coke quenching circulating gas well, resulting in excessively high temperature of the circulating gas and excessively high flue gas temperature outside the heating surface pipes of the boiler, which can easily cause corrosion of the pipes and lead to pipe bursts. Utility Model Content
[0003] The purpose of the embodiments of the present application is to provide a boiler system and a dry coke quenching system, which can reduce the probability of pipe bursting caused by corrosion of the dry coke quenching boiler pipe. The specific technical solution is as follows:
[0004] An embodiment of the first aspect of the present application provides a boiler system, which is applied to a dry coke quenching system. The boiler system includes: a direct current unit and a recirculation unit, wherein the direct current unit includes: a direct current pipeline, a water spray desuperheater, a boiler feed water pump, an economizer, a mixer, an evaporator, a water-cooled wall, a low-temperature superheater and a high-temperature superheater connected in sequence through the direct current pipeline, and the water spray desuperheater is arranged between the low-temperature superheater and the high-temperature superheater; a recirculation unit, wherein the recirculation unit includes a first recirculation pipeline, a first forced circulation pump and a first recirculation valve arranged on the first recirculation pipeline; the inlet of the first recirculation pipeline is connected to the outlet of the water-cooled wall, the outlet of the first recirculation pipeline is connected to the inlet of the mixer, the first recirculation valve is connected to the inlet of the first forced circulation pump, and the first recirculation valve is used to control the opening and closing of the first recirculation pipeline.
[0005] In some embodiments, the first recirculation pipeline further includes a first check valve, and the first check valve is disposed between the first recirculation valve and the first forced circulation pump.
[0006] In some embodiments, the recycling unit further includes a first bypass pipe, a first end of the first bypass pipe being disposed between the first check valve and the first forced circulation pump, a second end of the first bypass pipe being disposed between the first forced circulation pump and the mixer, and a first gate valve being disposed on the first bypass pipe.
[0007] In some embodiments, the first end of the first bypass conduit is located closer to the first check valve.
[0008] In some embodiments, the recycling unit further includes a circulation pump bypass pipe, one end of which is connected to the outlet of the first recycling valve, and the other end of which is connected to the inlet of the mixer, and a second forced circulation pump is provided on the circulation pump bypass pipe.
[0009] In some embodiments, a second gate valve is provided on the circulation pump bypass pipeline, and the second gate valve is located between the outlet of the second forced circulation pump and the inlet of the mixer.
[0010] In some embodiments, the water-cooled wall is a single-rise type water-cooled wall.
[0011] In some embodiments, the boiler system further includes a water inlet pipe, which is connected to the boiler feed water pump, and the water inlet pipe is provided with a filtering device for filtering impurities in the boiler feed water.
[0012] In some embodiments, a flow regulating valve is provided between the boiler feed water pump and the economizer.
[0013] An embodiment of the second aspect of the present application provides a coke dry quenching system, the coke dry quenching system comprising: the boiler system described above.
[0014] The boiler system provided in the embodiment of the present application, when the boiler system is at rated load or high load, the boiler feed water enters the economizer and the evaporator through the boiler feed water pump to absorb heat, the feed water is gradually heated to a saturated state, and then enters the water-cooled wall to further absorb heat, gradually generating saturated steam, and the saturated steam then enters the low-temperature superheater and the high-temperature superheater to generate the required superheated steam that meets the required quality; when the boiler system is at low load, the boiler feed water enters the economizer and the evaporator through the boiler feed water pump to absorb heat, the feed water is gradually heated to a saturated state, and then enters the water-cooled wall to further absorb heat, and gradually generates saturated steam, and the saturated steam enters the low-temperature superheater and the high-temperature superheater, while the unsaturated medium and the partially saturated medium enter the first recirculation pipe through the first forced circulation pump, are mixed with the medium heated by the economizer in the mixer, and enter the evaporator and the water-cooled wall again, absorbing heat in a reciprocating cycle to generate the required superheated steam that meets the required quality. Therefore, the boiler can generate sufficient superheated steam under different working conditions, thereby improving the working efficiency of the boiler system.
[0015] Of course, any product implementing the present application does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.
[0017] Figure 1 A schematic diagram of a boiler system provided in an embodiment of the present application;
[0018] Figure 2 A schematic diagram of another boiler system provided in an embodiment of the present application;
[0019] Figure 3 A schematic diagram of another boiler system provided in an embodiment of the present application;
[0020] Figure 4 A schematic diagram of another boiler system provided in an embodiment of the present application.
[0021] Reference numerals:
[0022] DC unit 10; boiler feed water pump 11; economizer 12; mixer 13; evaporator 14; water-cooled wall 15; low-temperature superheater 16; high-temperature superheater 17; water spray desuperheater 18; recirculation unit 20; first recirculation pipeline 21; third gate valve 210; first forced circulation pump 22; first recirculation valve 23; first check valve 24; first bypass pipeline 25; first gate valve 26; second recirculation pipeline 27; third forced circulation pump 271; second recirculation valve 272; second check valve 273; second bypass pipeline 274; fourth gate valve 275; third bypass pipeline 28; fifth gate valve 281; circulation pump bypass pipeline 90; second forced circulation pump 91; second gate valve 92; sixth gate valve 93; user end 30. DETAILED DESCRIPTION
[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field based on the present application belong to the scope of protection of the present application.
[0024] Domestic CDQ technology has become increasingly mature. Currently, CDQ boilers all use natural circulation. Since the density of steam-water mixture is smaller than that of water, the natural circulation boiler uses this density difference to generate the circulation of water and steam-water mixture. When the current CDQ boiler is running at low load, the medium mass in the high-temperature superheater, low-temperature superheater, evaporator, and economizer is small, and the temperature of the CDQ circulating gas remains basically unchanged. The working fluid cannot better absorb the heat in the CDQ circulating gas, resulting in excessively high flue gas temperatures outside the heating surface pipes, which can easily cause pipeline corrosion and lead to pipe bursts.
[0025] The embodiment of the first aspect of the present application provides a boiler system, which is applied to a coke dry quenching system, such as Figure 1 As shown, the boiler system includes: a direct current unit 10 and a recirculation unit 20. The direct current unit 10 includes: a direct current pipeline, a water spray desuperheater 18, a boiler feed water pump 11, an economizer 12, a mixer 13, an evaporator 14, a water wall 15, a low-temperature superheater 16 and a high-temperature superheater 17 which are sequentially connected through the direct current pipeline. The water spray desuperheater 18 is arranged between the low-temperature superheater 16 and the high-temperature superheater 17; and the water spray desuperheater 18 is connected to the low-temperature superheater 16 and the high-temperature superheater 17. The recirculation unit 20 includes a first recirculation pipeline 21, a first forced circulation pump 22 and a first recirculation valve 23 arranged on the first recirculation pipeline 21; the inlet of the first recirculation pipeline 21 is connected to the outlet of the water wall 15, the outlet of the first recirculation pipeline 21 is connected to the inlet of the mixer 13, the first recirculation valve 23 is connected to the inlet of the first forced circulation pump 22, and the first recirculation valve 23 is used to control the on-off of the first recirculation pipeline 21.
[0026] In the embodiment of the present application, when the boiler system is at rated load or high load, the boiler feed water may not enter the recirculation unit 20, and only generate superheated steam through the direct current unit 10 to achieve the form of maximizing the working fluid flow rate, that is, the boiler feed water reaches or is close to the rated flow rate. Specifically, the boiler feed water enters the economizer 12 and the evaporator 14 through the boiler feed water pump 11 to absorb heat, and the feed water is gradually heated to a saturated state, and then enters the water-cooled wall 15 to further absorb heat, and gradually produces saturated steam. The saturated steam then enters the low-temperature superheater 16 and the high-temperature superheater 17 to generate the required superheated steam that meets the required quality; when the boiler system is at low load, the boiler feed water enters the economizer 12 and the evaporator 14 through the boiler feed water pump 11 to absorb heat, and the feed water is gradually heated to a saturated state, and then enters the water-cooled wall 15 to further absorb heat, and gradually produces Saturated steam is generated, and the saturated steam enters the low-temperature superheater 16 and the high-temperature superheater 17, while the unsaturated medium and the partially saturated medium enter the first recirculation pipeline 21 through the first forced circulation pump 22, and are mixed with the medium heated by the economizer 12 in the mixer 13 and enter the evaporator 14 and the water-cooled wall 15 again, and the reciprocating cycle absorbs heat, ensuring that the quality of the medium in the pipeline operates according to the rated working conditions, fully absorbing the heat in the circulating gas, reducing the pipe burst caused by the corrosion of the pipeline due to the high temperature of the flue gas outside the pipeline, and generating the required superheated steam that meets the required quality and sending it to the user end 30. Therefore, the boiler can generate sufficient superheated steam under different working conditions, which improves the working efficiency of the boiler system.
[0027] After the circulating working fluid in the first recirculation pipe 21 is mixed with the new working fluid in the mixer 13, they flow into the evaporator 14 and the water-cooled wall 15 together, so that the enthalpy value of the working fluid at the inlet of the evaporator 14 and the water-cooled wall 15 is increased, the under-enthalpy is reduced, and the enthalpy increase in the evaporator 14 and the water-cooled wall 15 is also reduced, which is beneficial to improving the Rankine efficiency and is also beneficial to the stability of the working fluid flow in the evaporator 14 and the water-cooled wall 15 and reducing thermal deviation.
[0028] Moreover, the water-cooled wall 15 adopts a water-cooled pipe with a larger diameter, which can achieve water vapor separation, so that the boiler system does not need to set up a steam drum, reduce the devices in the boiler system, and thus save the cost of the boiler system. Through the above-mentioned settings, the boiler system adopts a compound circulation circulation method, increases the mass of the medium in the heating surface by recirculation, and increases the absorption of heat outside the pipeline. When the composite circulation boiler operates within a low load range, the flow rate of the working fluid changes little, and the temperature change range is also small, which reduces the thermal stress of the working fluid and is conducive to improving the stability of the boiler when it is running at low load. The load adjustment range of the composite circulation direct current boiler is wide, from 10% to 100%, which can meet the characteristics of frequent load adjustment of dry coke quenching. And many regions currently require full dry quenching operation, requiring the boiler to be either cold standby or the boiler to be in a low load state, and the boiler is in a low load state for a long time, which is more suitable for composite circulation direct current boilers. It can adapt to a wider range of load adjustment, better operating stability, reduce energy loss during low load operation, and reduce the risk of pipe bursting.
[0029] At present, the minimum operating load of natural circulation boilers in CDQ boilers is about 30% of the rated load, while the minimum load of CDQ boilers using compound circulation once-through boilers is 5%~10% of the rated load, which greatly reduces the minimum operating load of the boiler, significantly reduces equipment costs, reduces energy losses during low-load operation, and avoids frequent tube bursts on the boiler heating surface.
[0030] It should be noted that the combined circulation once-through boiler starts at 30% of the rated load, which is higher than the natural circulation boiler, to ensure the safe operation of the boiler heating surface during startup.
[0031] It should be noted that the forced circulation pump consumes a certain amount of electric energy during operation. Generally, the power of the pump is about 0.2%~0.3% of the power of the unit. In addition, the forced circulation pump works for a long time under high temperature and high pressure. It is necessary to regularly maintain the forced circulation pump to ensure that the pump has sufficient safety and reliability. At the same time, the flow-pressure head characteristics of the forced circulation pump must also match the pressure drop characteristics of the water-cooled wall 15 and the evaporator 14 system to meet the design requirements. When designing a composite circulation boiler, the mass flow rate at rated load can be selected to be lower to reduce flow resistance and energy consumption of the forced circulation pump. When the composite circulation boiler operates within the low load range, the flow rate of the working fluid changes little, and the temperature change range is also small, which reduces the thermal stress of the working fluid and is conducive to improving the stability of the boiler when it is running at low load. The load of the composite circulation direct current boiler from recirculation to direct current operation is generally 65%~80% of the rated load.
[0032] The first forced circulation pump 22 can provide power to the boiler feed water, so that the boiler feed water can be better recycled.
[0033] Specifically, the first recirculation valve 23 may be an electric regulating valve or an electric stop valve.
[0034] like Figure 3 As shown, the first recirculation pipeline 21 is further provided with a third gate valve 210, which is communicated with the inlet of the first recirculation valve 23. By providing the third gate valve 210, the system safety can be further improved. The recirculation unit 20 also includes a third bypass pipeline 28, which is connected in parallel with the first recirculation valve 23. Two fifth gate valves 281 are provided on the third bypass pipeline 28. When the first recirculation valve 23 fails, the medium discharged from the water-cooled wall 15 can flow out from the third bypass pipeline 28.
[0035] In some embodiments of the present application, Figure 1 As shown, the first recirculation pipeline further includes a first check valve 24 , which is disposed between the first recirculation valve 23 and the first forced circulation pump 22 .
[0036] In the embodiment of the present application, the first check valve 24 is arranged between the first recirculation valve 23 and the first forced circulation pump 22, so that the boiler feed water can flow in one direction, that is, from the first recirculation valve 23 to the first forced circulation pump 22, to prevent the boiler feed water from flowing back.
[0037] In some embodiments of the present application, Figure 1 As shown, the recycling unit 20 also includes a first bypass pipe 25, a first end of the first bypass pipe 25 is arranged between the first check valve 24 and the first forced circulation pump 22, and a second end is arranged between the first forced circulation pump 22 and the mixer 13, and a first gate valve 26 is provided on the first bypass pipe 25.
[0038] In the embodiment of the present application, the two ends of the first bypass pipe 25 are respectively arranged at the two ends of the first forced circulation pump 22. When the first forced circulation pump 22 is damaged, the first gate valve 26 on the first bypass pipe 25 is opened, so that the boiler feed water in the first recirculation pipe 21 can flow to the mixer 13 through the first bypass pipe 25.
[0039] It should be noted that there may be two first gate valves 26 .
[0040] In some embodiments of the present application, Figure 1 As shown, the first end of the first bypass pipe 25 is located closer to the first check valve 24. Specifically, the first check valve 24 is arranged on a side of the first check valve 24 close to the first recirculation valve 23, so that the first bypass pipe 25 and the first recirculation pipe 21 can share the same first check valve 24, thereby reducing the number of devices in the boiler system.
[0041] In some embodiments of the present application, Figure 4As shown, the recycling unit 20 also includes a circulation pump bypass pipe 90, one end of which is connected to the outlet of the first recirculation valve 23, and the other end is connected to the inlet of the mixer 13. The circulation pump bypass pipe 90 is provided with a second forced circulation pump 91.
[0042] In the embodiment of the present application, the second forced circulation pump 91 is arranged in parallel with the first forced circulation pump 22. When the first forced circulation pump 22 fails, the second forced circulation pump 91 can be opened to facilitate the maintenance of the first forced circulation pump 22. Similarly, when the second forced circulation pump 91 fails, the first forced circulation pump 22 can be opened to facilitate the maintenance of the second forced circulation pump 91. By providing the circulation pump bypass pipeline 90, the time required for maintenance due to damage to the forced circulation pump can be reduced to ensure the normal operation of the dry quenching boiler system.
[0043] In some embodiments of the present application, Figure 4 As shown, a second gate valve 92 is provided on the circulation pump bypass pipeline 90, and the second gate valve 92 is located between the outlet of the second forced circulation pump 91 and the inlet of the mixer 13. A sixth gate valve 93 may also be provided between the outlet of the first forced circulation pump 22 and the inlet of the mixer 13. The second gate valve 92 is used to control the on-off of the circulation pump bypass pipeline 90. When the amount of water in the mixer 13 is too much, the pipeline is closed by the second gate valve 92 or the sixth gate valve 93, so that the water in the pipeline cannot enter the mixer 13.
[0044] In some embodiments of the present application, Figure 2 As shown, the recirculation unit 20 also includes a second recirculation pipe 27, and a third forced circulation pump 271 and a second recirculation valve 272 arranged on the second recirculation pipe 27, the inlet of the second recirculation pipe 27 is connected to the outlet of the water-cooled wall 15, and the outlet of the second recirculation pipe 27 is connected to the inlet of the mixer 13.
[0045] In the embodiment of the present application, the second recirculation pipeline 27 is arranged in parallel with the first recirculation pipeline 21. When the first recirculation pipeline 21, the first forced circulation pump 22 or the first recirculation valve 23 fails and the boiler feed water cannot circulate through the first recirculation pipeline 21, the second recirculation valve 272 is opened to allow the boiler feed water to recirculate through the second recirculation pipeline. Through the above arrangement, the reliability of the boiler system operation is improved.
[0046] It should be noted that if Figure 2 As shown, when the first recirculation pipeline 21 can be used normally, the second recirculation valve 272 is in a closed state.
[0047] In some embodiments of the present application, Figure 2As shown, a second check valve 273 is provided on the second recirculation pipeline 27 , and the second check valve 273 is provided between the second recirculation valve 272 and the third forced circulation pump 271 .
[0048] In the embodiment of the present application, similar to the first check valve 24, the second check valve 273 is arranged between the second recirculation valve 272 and the third forced circulation pump 271, so that the boiler feed water can flow in one direction, that is, from the second recirculation valve 272 to the third forced circulation pump 271, to prevent the boiler feed water from flowing back.
[0049] The same is true for the first gate valve 26. Figure 3 As shown, a fourth gate valve 275 is also provided on the second bypass pipe 274. In some embodiments of the present application, the water-cooled wall 15 is a one-time rising type water-cooled wall 15. For a composite circulation once-through dry quenching boiler with a small capacity, a one-time rising type water-cooled wall 15 can be used. The larger pipe diameter of the water-cooled wall 15 can keep the working medium within a safe flow rate range and reduce the impact on the pipeline.
[0050] In some embodiments of the present application, the boiler system further includes a water inlet pipe (not shown), which is connected to the boiler feed water pump 11 and is provided with a filtering device for filtering impurities in the boiler feed water.
[0051] In the embodiment of the present application, a filtering device is provided on the water inlet pipe, which can filter impurities in the boiler feed water, reduce the probability of impurities wearing other components in the boiler system, and increase the service life of the boiler system.
[0052] In some embodiments of the present application, a flow regulating valve (not shown) is provided between the boiler feed water pump 11 and the economizer 12 .
[0053] In the embodiment of the present application, the flow rate entering the economizer 12 can be adjusted by a flow regulating valve to achieve controllable boiler feed water.
[0054] An embodiment of the second aspect of the present application provides a coke dry quenching system, which includes: the above boiler system.
[0055] In the embodiment of the present application, when the boiler system is at rated load or high load, the boiler feed water enters the economizer 12 and the evaporator 14 through the boiler feed water pump 11 to absorb heat, and the feed water is gradually heated to a saturated state, and then enters the water-cooled wall 15 to further absorb heat, gradually generating saturated steam, and the saturated steam then enters the low-temperature superheater 16 and the high-temperature superheater 17 to generate the required superheated steam that meets the required quality; when the boiler system is at low load, the boiler feed water enters the economizer 12 and the evaporator 14 through the boiler feed water pump 11 to absorb heat, and the feed water is gradually heated to a saturated state. The medium enters the saturated state, and then enters the water-cooled wall 15 to further absorb heat, gradually generating saturated steam, and the saturated steam enters the low-temperature superheater 16 and the high-temperature superheater 17, while the unsaturated medium and the partially saturated medium enter the recirculation pipeline through the first forced circulation pump 22, and are mixed with the medium heated by the economizer 12 in the mixer 13 and enter the evaporator 14 and the water-cooled wall 15 again, absorbing heat in a reciprocating cycle to generate the required superheated steam that meets the required quality. Therefore, the boiler can generate sufficient superheated steam under different working conditions, thereby improving the working efficiency of the boiler system. Moreover, the water-cooled wall 15 uses a water-cooled pipe with a larger diameter, which can achieve water-vapor separation, so that the boiler system does not need to set up a steam drum, reducing the equipment in the boiler system, and thus saving the cost of the boiler system.
[0056] The CDQ system also includes a CDQ furnace, a primary dust collector, a circulating fan, a secondary dust collector, and a heat exchanger. The CDQ furnace, the primary dust collector, the boiler, the secondary dust collector, the circulating fan, and the heat exchanger are connected in sequence. The low-temperature circulating gas cools the red-hot coke in the CDQ furnace. After being discharged from the CDQ furnace, it is a high-temperature circulating gas. After being dusted by the primary dust collector, it enters the boiler system to generate steam. After being discharged from the boiler system, the circulating gas enters the heat exchanger for further cooling, and enters the CDQ furnace again to cool the coke, thus realizing the circulation of the circulating gas. The boiler system does not need to burn fuel to generate steam, but uses the circulating gas to cool the coke, making the CDQ system more energy-efficient.
[0057] The above description is only a preferred embodiment of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.
Claims
1. A boiler system, characterized in that: Applied to CDQ system, including: A direct current unit (10), the direct current unit (10) comprising: a direct current pipeline, a boiler feed water pump (11), an economizer (12), a mixer (13), an evaporator (14), a water-cooled wall (15), a low-temperature superheater (16), a high-temperature superheater (17), and a water spray desuperheater (18) which are sequentially connected via the direct current pipeline; The water spray desuperheater (18) is arranged between the low-temperature superheater (16) and the high-temperature superheater (17); A recirculation unit (20), the recirculation unit (20) comprising a first recirculation pipeline (21), a first forced circulation pump (22) and a first recirculation valve (23) provided on the first recirculation pipeline (21); The inlet of the first recirculation pipe (21) is connected to the outlet of the water-cooled wall (15), the outlet of the first recirculation pipe (21) is connected to the inlet of the mixer (13), the first recirculation valve (23) is connected to the inlet of the first forced circulation pump (22), and the first recirculation valve (23) is used to control the opening and closing of the first recirculation pipe (21).
2. The boiler system according to claim 1, characterized in that: The first recirculation pipeline (21) further comprises a first check valve (24), wherein the first check valve (24) is arranged between the first recirculation valve (23) and the first forced circulation pump (22).
3. The boiler system according to claim 2, characterized in that: The recirculation unit (20) further comprises a first bypass pipeline (25), wherein a first end of the first bypass pipeline (25) is arranged between the first check valve (24) and the first forced circulation pump (22), and a second end of the first bypass pipeline (25) is arranged between the first forced circulation pump (22) and the mixer (13), and a first gate valve (26) is arranged on the first bypass pipeline (25).
4. The boiler system according to claim 3, characterized in that: The first end of the first bypass pipe (25) is located closer to the first check valve (24).
5. The boiler system according to claim 1, characterized in that: The recirculation unit (20) further comprises a circulation pump bypass pipe (90), one end of the circulation pump bypass pipe (90) being in communication with the outlet of the first recirculation valve (23), and the other end of the circulation pump bypass pipe (90) being in communication with the inlet of the mixer (13), and a second forced circulation pump (91) being provided on the circulation pump bypass pipe (90).
6. The boiler system according to claim 5, characterized in that: A second gate valve (92) is provided on the circulation pump bypass pipeline (90), and the second gate valve (92) is located between the outlet of the second forced circulation pump (91) and the inlet of the mixer (13).
7. The boiler system according to any one of claims 1 to 6, characterized in that: The water-cooled wall (15) is a single-rise type water-cooled wall (15).
8. The boiler system according to any one of claims 1 to 6, characterized in that: The boiler system further comprises a water inlet pipe, the water inlet pipe being in communication with a boiler feed water pump (11), the water inlet pipe being provided with a filtering device for filtering impurities in the boiler feed water.
9. The boiler system according to any one of claims 1 to 6, characterized in that: A flow regulating valve is provided between the boiler feed water pump (11) and the economizer (12).
10. A coke dry quenching system, characterized in that: include: The boiler system according to any one of claims 1 to 9.