A steam exhaust recovery system for a thermal power plant

Abstract

The utility model relates to a kind of thermal power plant exhaust steam recovery system, including boiler;Split cylinder, the main steam inlet of split cylinder is connected with the steam outlet of boiler by pipeline;Heat recovery mechanism, heat recovery mechanism is connected with the emptying pipeline of split cylinder by pipeline;And to be heated mechanism, to be heated mechanism is communicated with heat recovery mechanism by pipeline, heat recovery mechanism is used to recover the steam discharged by split cylinder, and the heat of recovered steam is transmitted to to be heated mechanism. Heat recovery mechanism is directly connected with the emptying pipeline of split cylinder by pipeline, replaces original simple emptying structure, receives redundant steam from source, avoids steam direct discharge. To be heated mechanism is communicated with heat recovery mechanism by pipeline, forms heat transfer channel, so that the heat of recovered steam can be secondary used by production system. Break the existing "direct emptying" processing mode, fundamentally solve the problem that redundant steam cannot be recovered, avoid high-quality steam waste, reduce energy loss.

Description

Technical Field

[0001] This utility model relates to the field of steam recovery and utilization technology in thermal power plants, and specifically to a thermal power plant exhaust steam recovery system. Background Technology

[0002] In the paper industry's production support system, thermal power plants and paper machine production lines typically employ a fixed steam supply and demand linkage model. Under current technology, thermal power plants only operate a single back-pressure turbine unit during normal production, while extraction-condensing units remain shut down for extended periods. This is to meet the continuous steam demand of four paper machine production lines. During paper machine production, a continuous supply of process steam at a pressure of 0.6 MPa and a temperature of 250°C is required. These steam parameters are crucial for ensuring paper forming quality and production efficiency.

[0003] However, paper machine production is prone to paper breakage due to various factors such as fluctuations in raw material characteristics, abnormal equipment operation, and operational deviations. In such cases, it is necessary to immediately stop the steam supply and restart the paper feeding operation, a process that typically lasts about 30 minutes. During this period, the core challenges are concentrated in three aspects: First, the steam consumption of back-pressure turbine units is strongly tied to the steam consumption of the paper machine, and their operating characteristics make it impossible to flexibly adjust the load to absorb excess steam after a paper breakage. Second, as a steam generating device, the boiler exhibits a significant time lag in load adjustment, making it impossible to quickly reduce steam production within the 30-minute paper breakage window. Forced rapid load adjustment could easily lead to unstable combustion in the boiler furnace and overheating of the heating surfaces, posing safety hazards. Third, the existing steam delivery system only has a steam distribution cylinder for venting air and lacks a dedicated device for recovering and utilizing excess steam.

[0004] The aforementioned contradiction directly resulted in the inability to effectively dispose of excess steam generated during paper cutoffs. To prevent damage to equipment such as steam distribution cylinders and steam pipelines due to excessive pressure and temperature, the excess steam could only be directly discharged into the air through the steam distribution cylinder's vent. According to actual operating data, the average monthly venting volume of the steam distribution cylinder under such conditions reaches approximately 200 tons. This not only resulted in a significant waste of high-quality steam and a substantial increase in the company's energy consumption costs, but also created environmental pressure due to the noise and thermal pollution generated during the steam venting process. Utility Model Content

[0005] Therefore, a thermal power plant exhaust steam recovery system is needed to address the issue of stopping steam and restarting the paper feeding process when abnormal paper breaks occur during production. This process typically takes about 30 minutes, and the back pressure unit of the thermal power plant cannot consume the excess steam. As a result, the excess steam needs to be vented to the outside through the steam distribution cylinder, which not only wastes a large amount of high-quality steam and significantly increases the company's energy consumption costs, but also poses certain environmental pressures due to the noise and thermal pollution generated during the steam venting process.

[0006] To achieve the above objectives, the inventors provide a thermal power plant exhaust steam recovery system, comprising:

[0007] boiler;

[0008] The steam distribution cylinder has its main steam inlet connected to the steam outlet of the boiler via a pipeline.

[0009] A heat recovery mechanism is connected to the exhaust pipe of the steam distribution cylinder via a pipeline;

[0010] The heating mechanism is connected to the heat recovery mechanism via a pipeline. The heat recovery mechanism is used to recover the steam discharged from the steam distribution cylinder and transfer the heat of the recovered steam to the heating mechanism.

[0011] As a preferred structure of this utility model, the heat recovery mechanism includes a multi-layer heat recovery cavity and multiple guide pipes;

[0012] The heat recovery chambers in the multiple layers are separated by partitions, and the heat recovery chambers in the multiple layers are interconnected;

[0013] The multiple guide tubes are respectively disposed in the multiple heat recovery chambers;

[0014] The heating mechanism includes multiple conveying and circulating pipelines, which are respectively connected to multiple guide pipes.

[0015] As a preferred structure of this utility model, the multi-layer heat recovery cavity includes an upper heat recovery cavity, a middle heat recovery cavity, and a lower heat recovery cavity, which are arranged sequentially from top to bottom.

[0016] The plurality of guide tubes include a first guide tube, a second guide tube, and a third guide tube. The first guide tube is disposed in the upper heat recovery cavity, the second guide tube is disposed in the middle heat recovery cavity, and the third guide tube is disposed in the lower heat recovery cavity.

[0017] As a preferred structure of this utility model, the plurality of conveying circulation pipelines include a first conveying circulation pipeline, a second conveying circulation pipeline, and a third conveying circulation pipeline;

[0018] The first conveying circulation pipeline is connected to the first guide pipe, the second conveying circulation pipeline is connected to the second guide pipe, and the third conveying circulation pipeline is connected to the third guide pipe;

[0019] The heating mechanism also includes a high-pressure heater, a condensate tank, a demineralized water tank, and a deaerator;

[0020] The inlet of the first conveying circulation pipeline is connected to the high-pressure heater, and the outlet of the first conveying circulation pipeline is connected to the deaerator. The high-pressure heater is used to provide water to the first conveying circulation pipeline.

[0021] The inlet of the second conveying circulation pipeline is connected to the condensate tank, and the outlet of the second conveying circulation pipeline is connected to the deaerator. The condensate tank is used to provide water to the second conveying circulation pipeline.

[0022] The inlet of the third conveying circulation pipeline is connected to the demineralized water tank, and the outlet of the third conveying circulation pipeline is connected to the deaerator. The demineralized water tank is used to provide water to the third conveying circulation pipeline.

[0023] In a preferred embodiment of this invention, the first guide tube is arranged in a spiral pattern within the upper heat recovery cavity, the second guide tube is arranged in a spiral pattern within the middle heat recovery cavity, and the third guide tube is arranged in a spiral pattern within the lower heat recovery cavity.

[0024] As a preferred structure of this utility model, the heat recovery mechanism further includes multiple guide plates, which are staggered and spaced apart in the upper heat recovery cavity.

[0025] As a preferred structure of this utility model, the heat recovery mechanism further includes a buffer cavity, which is disposed on top of the upper heat recovery cavity and is connected to the upper heat recovery cavity. The buffer cavity is also connected to the exhaust pipe of the steam distribution cylinder through a pipeline.

[0026] As a preferred structure of this utility model, the heat recovery mechanism further includes a condensate chamber;

[0027] The condensate chamber is located at the bottom of the lower heat recovery chamber, and the condensate chamber is connected to the lower heat recovery chamber.

[0028] The condensate chamber and the condensate tank are connected by a pipeline.

[0029] As a preferred structure of this utility model, the thermal power plant exhaust steam recovery system further includes a control valve, which is installed on the pipeline between the condensate chamber and the drain tank.

[0030] The condensate chamber is installed at a higher height than the condensate tank.

[0031] As a preferred structure of this utility model, the exhaust steam recovery system of the thermal power plant further includes a regulating valve, which is installed on the pipeline between the heat recovery mechanism and the exhaust pipe of the steam distribution cylinder.

[0032] Unlike existing technologies, the beneficial effects of the above technical solution are as follows: Specifically, in the power plant exhaust steam recovery system of this embodiment, the boiler's steam outlet is connected to the main steam inlet of the steam distributor via a pipeline. Under normal operating conditions, process steam at 0.6MPa and 250℃ is supplied to the steam distributor; under interrupted operating conditions, the steam continuously generated by the boiler is discharged through the exhaust pipe of the steam distributor. The heat recovery mechanism is directly connected to the exhaust pipe of the steam distributor via a pipeline, replacing the original simple exhaust structure, receiving excess steam from the source, and avoiding direct steam discharge. The heating mechanism and the heat recovery mechanism are connected via pipeline to form a heat transfer channel, enabling the heat of the recovered steam to be reused by the production system. This breaks the existing "direct exhaust" processing mode, fundamentally solving the problem of excess steam not being recovered, avoiding the waste of high-quality steam, constructing a closed loop of "steam generation-recovery-heat reuse," reducing energy consumption, lowering enterprise energy costs, avoiding noise and heat pollution generated by steam exhaust, and alleviating environmental pressure.

[0033] The above description of the utility model is merely an overview of the technical solution of this application. In order to enable those skilled in the art to better understand the technical solution of this application and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this application easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this application. Attached Figure Description

[0034] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of specific embodiments of this application and other related content, and should not be considered as limitations on this application.

[0035] In the accompanying drawings of the instruction manual:

[0036] Figure 1 This is one of the process diagrams of the exhaust steam recovery system of the thermal power plant described in the specific implementation method;

[0037] Figure 2 This is the second schematic diagram of the exhaust steam recovery system of the thermal power plant described in the specific implementation method;

[0038] Figure 3 This is the third schematic diagram of the process of the exhaust steam recovery system of the thermal power plant described in the specific implementation method;

[0039] Figure 4 This is the fourth schematic diagram of the process of the exhaust steam recovery system of the thermal power plant described in the specific implementation method;

[0040] Figure 5 This is a schematic diagram showing the unfolded heat recovery mechanism described in a specific embodiment.

[0041] The reference numerals used in the above figures are explained as follows:

[0042] 1. Boiler

[0043] 2. Steam distributor cylinder,

[0044] 3. Heat recovery mechanism,

[0045] 31. Partition,

[0046] 32. Upper heat recovery chamber,

[0047] 321. Deflector plate,

[0048] 33. Middle layer heat recovery chamber,

[0049] 34. Lower heat recovery chamber,

[0050] 35. First guide tube,

[0051] 36. Second guide tube,

[0052] 37. Third diversion tube,

[0053] 38. Buffer cavity,

[0054] 39. Condensate cavity,

[0055] 4. Heating mechanism,

[0056] 41. First conveying and circulation pipeline,

[0057] 42. Second conveying and circulation pipeline,

[0058] 43. Third conveying and circulation pipeline,

[0059] 44. High-pressure heater,

[0060] 45. Drainage tank,

[0061] 46. ​​Demineralized water tank,

[0062] 47. Deaerator

[0063] 5. Control valves,

[0064] 6. Control valve. Detailed Implementation

[0065] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.

[0066] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0067] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0068] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.

[0069] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.

[0070] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0071] As understood in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0072] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. These expressions are only for the convenience of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. Furthermore, in this context, it should be understood that when it is mentioned that an element is connected "on" or "below" another element, it can be directly connected not only to the other element "on" or "below," but also indirectly connected to the other element "on" or "below" through an intermediate element.

[0073] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0074] Please see Figures 1 to 5 This embodiment relates to a thermal power plant exhaust steam recovery system, comprising:

[0075] Boiler 1; Boiler 1 is the core equipment for steam generation, providing high-quality process steam for the paper machine production line and recycling system.

[0076] Steam distributor 2, the main steam inlet of which is connected to the steam outlet of the boiler 1 through a pipeline; wherein steam distributor 2 is a steam distribution and buffering device, used to receive the steam generated by the boiler 1 and distribute it to the paper machine production line, and at the same time discharge excess steam under paper breakage conditions through the venting pipe.

[0077] The heat recovery mechanism 3 is connected to the vent pipe of the steam distribution cylinder 2 via a pipeline; the heat recovery mechanism 3 is the core component that receives the vented steam from the steam distribution cylinder 2 and performs heat exchange, and is the key structure for realizing steam recovery.

[0078] The system includes a heating element 4, which is connected to the heat recovery element 3 via a pipeline. The heat recovery element 3 recovers the steam discharged from the steam distribution cylinder 2 and transfers the heat of the recovered steam to the heating element 4. The heating element 4 is a production-related equipment and piping system that needs to absorb heat, used to convert the recovered steam heat into usable energy for production.

[0079] Specifically, in this embodiment, such as Figures 1 to 5 As shown, the steam outlet of boiler 1 is connected to the main steam inlet of steam distributor 2 via a pipeline. Under normal operating conditions, it supplies process steam at 0.6 MPa and 250°C to steam distributor 2. Under interrupted operating conditions, the steam continuously generated by boiler 1 is discharged through the vent pipe of steam distributor 2. The heat recovery mechanism 3 is directly connected to the vent pipe of steam distributor 2 via a pipeline, replacing the original simple venting structure, and receiving excess steam from the source, avoiding direct steam discharge. The heating mechanism 4 is connected to the heat recovery mechanism 3 via a pipeline, forming a heat transfer channel, so that the heat of the recovered steam can be reused by the production system. This breaks the existing "direct venting" treatment mode, fundamentally solves the problem of excess steam not being recovered, avoids the waste of high-quality steam, and constructs a closed loop of "steam generation-recovery-heat reuse," reducing energy consumption, lowering enterprise energy costs, avoiding noise and heat pollution caused by steam venting, and alleviating environmental pressure.

[0080] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the heat recovery mechanism 3 includes multiple heat recovery chambers and multiple guide pipes; the multiple heat recovery chambers are separated by partitions 31 and are interconnected; the multiple guide pipes are respectively disposed in the multiple heat recovery chambers; the heating mechanism 4 includes multiple conveying circulation pipelines, which are respectively connected to the multiple guide pipes.

[0081] The multi-layer heat recovery chamber refers to multiple independent but interconnected steam-containing spaces separated by partitions 31. The partitions 31 divide the interior of the heat recovery mechanism 3 into multiple independent chambers, all interconnected, extending the residence time of steam within the chambers. The guide pipes are tubular structures that penetrate the heat recovery chambers and are used to transport the medium to be heated. Multiple guide pipes are correspondingly installed in each chamber, allowing the medium to flow within them and exchange heat fully with the steam within the chambers. This increases the contact area and contact time between the steam and the medium, improving heat exchange efficiency and preventing heat loss.

[0082] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the multi-layered heat recovery chamber includes an upper heat recovery chamber 32, a middle heat recovery chamber 33, and a lower heat recovery chamber 34, which are arranged sequentially from top to bottom. The plurality of guide pipes include a first guide pipe 35, a second guide pipe 36, and a third guide pipe 37. The first guide pipe 35 is disposed in the upper heat recovery chamber 32, the second guide pipe 36 is disposed in the middle heat recovery chamber 33, and the third guide pipe 37 is disposed in the lower heat recovery chamber 34.

[0083] The upper, middle, and lower heat recovery chambers 34 are three independent chambers arranged vertically from top to bottom. The first, second, and third guide pipes 37 are dedicated flow guiding structures adapted to the three chambers. Steam enters from the upper chamber and flows through the middle and lower chambers in sequence, forming a top-down flow path. The three guide pipes are embedded in their respective chambers, each conveying a different source of the medium to be heated, achieving simultaneous heat exchange of multiple media. The layered design optimizes the steam flow trajectory, avoids local steam accumulation, and ensures uniform heat exchange. The multi-guide pipe design increases the system's heat exchange capacity and adapts to the needs of different equipment to be heated.

[0084] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the multiple conveying circulation pipelines include a first conveying circulation pipeline 41, a second conveying circulation pipeline 42, and a third conveying circulation pipeline 43;

[0085] The first conveying circulation pipeline 41 is connected to the first guide pipe 35, the second conveying circulation pipeline 42 is connected to the second guide pipe 36, and the third conveying circulation pipeline 43 is connected to the third guide pipe 37; the heating mechanism 4 also includes a high-pressure heater 44, a condensate tank 45, a demineralized water tank 46, and a deaerator 47; wherein the conveying circulation pipeline is a closed pipeline connecting the equipment to be heated and the guide pipe, used to convey the medium to be heated; the high-pressure heater 44 is a device that provides a high-temperature water source for the system, the condensate tank 45 is a storage device for collecting production condensate, the demineralized water tank 46 is a container for storing demineralized water, and the deaerator 47 is a key production device for removing oxygen from the water.

[0086] Furthermore, the inlet of the first conveying circulation pipeline 41 is connected to the high-pressure heater 44, and the outlet of the first conveying circulation pipeline 41 is connected to the deaerator 47. The high-pressure heater 44 is used to provide water to the first conveying circulation pipeline 41. The first conveying circulation pipeline 41 connects the high-pressure heater 44 and the first guide pipe 35, conveying the water provided by the high-pressure heater 44 to the first guide pipe 35 of the upper cavity, where it absorbs heat and is then sent to the deaerator 47. The first conveying circulation pipeline 41 is connected to the high-pressure heater drain (around 120°C) to keep the cylinder in an expanded state, reducing thermal stress and improving heat transfer efficiency.

[0087] Furthermore, the inlet of the second conveying circulation pipeline 42 is connected to the condensate tank 45, and the outlet of the second conveying circulation pipeline 42 is connected to the deaerator 47. The condensate tank 45 is used to provide water to the second conveying circulation pipeline 42. The second conveying circulation pipeline 42 connects the condensate tank 45 and the second guide pipe 36, conveying the condensate in the condensate tank 45 to the second guide pipe 36 of the middle cavity, and after heat exchange, it flows into the deaerator 47. The second conveying circulation pipeline 42 drains water (below 100°C) from the condensate tank 45, keeping the cylinder in an expanded state, reducing thermal stress, and improving heat transfer efficiency.

[0088] Furthermore, the inlet of the third conveying circulation pipeline 43 is connected to the demineralized water tank 46, and the outlet of the third conveying circulation pipeline 43 is connected to the deaerator 47. The demineralized water tank 46 is used to provide water to the third conveying circulation pipeline 43. The third conveying circulation pipeline 43 connects the demineralized water tank 46 and the third guide pipe 37, conveying the demineralized water in the demineralized water tank 46 to the third guide pipe 37 in the lower cavity, where it is heated and then sent to the deaerator 47. The third conveying circulation pipeline 43 is connected to the deaerator 47's water supply header (at room temperature), which creates negative pressure in the lower cylinder, facilitating steam flow. In this embodiment, the thermal power plant exhaust steam recovery system designs dedicated pipelines for different sources of heated media (high-pressure water, condensate, demineralized water) to achieve simultaneous heating of multiple media and improve heat utilization. The heated media is directly conveyed to the deaerator 47, meeting the core equipment requirements of papermaking production and reducing the energy consumption required for separate heating of the deaerator 47. By integrating existing equipment in the production system, there is no need to add additional dedicated heating equipment, reducing the difficulty and cost of modification.

[0089] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the first guide pipe 35 is spirally distributed within the upper heat recovery cavity 32, the second guide pipe 36 is spirally distributed within the middle heat recovery cavity 33, and the third guide pipe 37 is spirally distributed within the lower heat recovery cavity 34. The spiral distribution refers to the guide pipes being arranged in a spiral or annular pattern within the cavity, rather than a straight, continuous structure. Within the limited cavity space, this maximizes the surface area and length of the guide pipes, extending the flow time of the heated medium within the cavity to further improve heat exchange efficiency, allowing the heated medium to fully absorb steam heat and improve energy utilization.

[0090] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the heat recovery mechanism 3 also includes multiple guide plates 321, which are staggered and spaced apart within the upper heat recovery cavity 32. Each guide plate 321 is a plate-like structure installed within the upper heat recovery cavity 32 to guide steam flow. The staggered arrangement means that the guide plates 321 are not collinear and are arranged alternately, disrupting the flow trajectory of steam after entering the upper cavity. This prevents steam from rapidly passing through the cavity, forces turbulence within the cavity, increases the contact frequency with the guide pipe, mitigates steam impact, prolongs steam residence time, and improves the heat exchange effect of the upper cavity, laying the foundation for deeper heat exchange in the subsequent middle and lower cavities.

[0091] Optionally, in some embodiments, such as Figures 1 to 5As shown, the heat recovery mechanism 3 also includes a buffer chamber 38, which is located on top of the upper heat recovery chamber 32 and communicates with it. The buffer chamber 38 is also connected to the vent pipe of the steam distributor 2 via a pipeline. The buffer chamber 38 is an independent space located on top of the upper heat recovery chamber 32 and communicating with it. It is used to mitigate the impact pressure when steam enters. Steam discharged from the steam distributor 2 first enters the buffer chamber 38, where its volume buffers the instantaneous impact force before flowing smoothly into the upper heat recovery chamber 32. This prevents high-pressure steam from directly impacting the internal structure of the heat recovery mechanism 3, extending the equipment's service life; it also prevents insufficient heat exchange due to excessively high steam flow rate, improving system stability.

[0092] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the heat recovery mechanism 3 also includes a condensate chamber 39; the condensate chamber 39 is located at the bottom of the lower heat recovery chamber 34 and is connected to the lower heat recovery chamber 34; the condensate chamber 39 is connected to the condensate trap 45 via a pipeline. The condensate chamber 39 is a storage space located at the bottom of the lower heat recovery chamber 34 for collecting liquid water formed after steam condensation. The condensate formed after steam condenses in the three chambers is collected by gravity to the condensate chamber 39 at the bottom of the lower chamber, and then transported to the condensate trap 45 via pipeline to achieve condensate recycling and reuse, avoiding waste of condensate; the condensate quality is close to the production water standard, and the water recovered to the condensate trap 45 can be directly used for subsequent production, reducing water consumption.

[0093] Optionally, in some embodiments, such as Figures 1 to 5 As shown, the thermal power plant exhaust steam recovery system also includes a control valve 5, which is installed on the pipeline between the condensate chamber 39 and the condensate tank 45. The control valve 5 is a switching component that regulates the condensate flow rate. Its installation on the pipeline between the condensate chamber 39 and the condensate tank 45 helps regulate the condensate flow rate, preventing overload of the condensate tank 45. Precise control of the condensate flow rate through the valve ensures stable operation of the condensate tank 45. Furthermore, the installation height of the condensate chamber 39 is higher than that of the condensate tank 45. This height difference design utilizes the height difference to create natural gravity flow, eliminating the need for an additional pump and achieving automatic condensate delivery, simplifying the system structure and reducing energy consumption.

[0094] Optionally, in some embodiments, such as Figures 1 to 5As shown, the power plant exhaust steam recovery system also includes a regulating valve 6, which is installed on the pipeline between the heat recovery mechanism 3 and the exhaust pipe of the steam distribution cylinder 2. The regulating valve 6 is a control component installed between the heat recovery mechanism 3 and the exhaust pipe of the steam distribution cylinder 2 to regulate the steam flow rate. Based on the pressure changes within the steam distribution cylinder 2 and the load-bearing capacity of the heat recovery mechanism 3, the steam flow rate entering the heat recovery mechanism 3 through the pipeline is automatically or manually adjusted to prevent excessive steam flow from causing overpressure damage to the heat recovery mechanism 3; it adapts to the steam discharge volume under different paper break durations, ensuring stable operation of the system under different operating conditions.

[0095] The thermal power plant exhaust steam recovery system in this embodiment, such as Figures 1 to 5 As shown, different functions are implemented under normal operating conditions and paper breakage conditions. The core workflow revolves around steam recovery under paper breakage conditions, as detailed below:

[0096] Normal production conditions: The 0.6MPa, 250℃ process steam generated by boiler 1 is transported to steam distributor 2 through pipeline. Steam distributor 2 distributes the steam to 4 paper machine production lines to meet the paper forming requirements. At this time, the exhaust pipe of steam distributor 2 is closed, the heat recovery mechanism 3 does not participate in the work, and the waiting heating mechanism 4 operates according to the original production process.

[0097] Paper breakage fault condition:

[0098] After the paper machine breaks down, the steam supply to the paper machine is immediately stopped. Boiler 1 continues to generate steam due to the load adjustment delay. Excess steam accumulates in the steam distribution cylinder 2, and the venting pipe of the steam distribution cylinder 2 is opened.

[0099] Excess steam enters the buffer chamber 38 of the heat recovery mechanism 3 through the vent pipe. The buffer chamber 38 alleviates the instantaneous impact of the steam, allowing the steam to flow smoothly into the upper heat recovery chamber 32. The guide plate 321 in the upper chamber disrupts the steam flow trajectory and prolongs the steam residence time, allowing the steam to undergo initial heat exchange with the high-pressure water in the first guide pipe 35.

[0100] After heat exchange in the upper chamber, the steam flows sequentially into the middle and lower heat recovery chambers 34, where it undergoes secondary and tertiary deep heat exchange with the condensate in the second guide pipe 36 and the demineralized water in the third guide pipe 37, respectively. All three guide pipes adopt a spiral distribution design to maximize the heat exchange area and ensure that the medium to be heated fully absorbs the heat from the steam.

[0101] After absorbing heat, the medium to be heated (high-pressure water, condensate, demineralized water) in the first, second, and third conveying circulation pipelines 43 is uniformly transported to the deaerator 47 through the pipelines, providing the deaerator 47 with a preheated medium and reducing the energy required for heating the deaerator 47.

[0102] After the steam completes heat exchange in the three-layer cavity, it condenses to form condensate, which is collected by gravity to the condensate cavity 39 at the bottom of the lower cavity. Taking advantage of the installation height difference between the condensate cavity 39 and the condensate tank 45, the condensate flows automatically into the condensate tank 45 through the pipeline, realizing condensate recovery.

[0103] During operation, regulating valve 6 adjusts the steam inflow in real time according to the pressure changes of steam distributor 2 and heat recovery mechanism 3 to ensure system safety.

[0104] Fault recovery condition: After the paper machine completes the re-feeding, the steam supply to the paper machine is restored, the vent pipe of the steam distribution cylinder 2 is closed, the heat recovery mechanism 3 stops receiving steam, and the system returns to normal production status.

[0105] The exhaust steam recovery system of the thermal power plant in this embodiment achieves multiple beneficial effects through targeted structural design, as detailed below:

[0106] Highly efficient energy recovery: approximately 200 tons of excess steam are recovered per month. The heat from the steam is fully converted into usable energy for production through multi-media heat exchange, significantly reducing the energy consumption of equipment such as the deaerator 47, increasing energy utilization by more than 30%, and significantly reducing the company's production costs.

[0107] Minimize environmental pressure: Replace the original direct steam venting mode, completely eliminate the high decibel noise and heat radiation pollution generated by steam venting, meet environmental emission requirements, and improve the production environment.

[0108] Comprehensive safety assurance: Through the synergistic effect of buffer chamber 38 and regulating valve 6, steam impact is effectively mitigated, steam flow is regulated, and overpressure risks are prevented, avoiding equipment damage caused by boiler 1 load adjustment delay and steam accumulation, and ensuring stable operation of the production system.

[0109] The system is highly adaptable: it integrates existing paper production equipment (deaerator 47, condensate tank 45, etc.) without requiring large-scale modifications to the original production line, making the modification difficult and cost controllable; the multi-layer heat exchange and multi-media adaptability design can cope with different steam parameter fluctuations and adapt to the instantaneous steam emission requirements of paper breakage conditions.

[0110] Maximizing resource utilization: Not only does it recover steam heat, but it also recovers condensate through the condensate chamber 39, reducing water waste and forming a dual recovery system of "heat energy and water resources", which is in line with the industrial development trend of energy conservation and consumption reduction.

[0111] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.

Claims

1. A thermal power plant exhaust steam recovery system, characterized in that, include: boiler; The steam distribution cylinder has its main steam inlet connected to the steam outlet of the boiler via a pipeline. A heat recovery mechanism is connected to the exhaust pipe of the steam distribution cylinder via a pipeline; The heating mechanism is connected to the heat recovery mechanism via a pipeline. The heat recovery mechanism is used to recover the steam discharged from the steam distribution cylinder and transfer the heat of the recovered steam to the heating mechanism.

2. The thermal power plant exhaust steam recovery system according to claim 1, characterized in that: The heat recovery mechanism includes a multi-layer heat recovery chamber and multiple guide pipes; The heat recovery chambers in the multiple layers are separated by partitions, and the heat recovery chambers in the multiple layers are interconnected; The multiple guide tubes are respectively disposed in the multiple heat recovery chambers; The heating mechanism includes multiple conveying and circulating pipelines, which are respectively connected to multiple guide pipes.

3. The thermal power plant exhaust steam recovery system according to claim 2, characterized in that: The multi-layered heat recovery chamber includes an upper heat recovery chamber, a middle heat recovery chamber, and a lower heat recovery chamber, which are arranged sequentially from top to bottom. The plurality of guide tubes include a first guide tube, a second guide tube, and a third guide tube. The first guide tube is disposed in the upper heat recovery cavity, the second guide tube is disposed in the middle heat recovery cavity, and the third guide tube is disposed in the lower heat recovery cavity.

4. The thermal power plant exhaust steam recovery system according to claim 3, characterized in that: The multiple conveying and circulating pipelines include a first conveying and circulating pipeline, a second conveying and circulating pipeline, and a third conveying and circulating pipeline; The first conveying circulation pipeline is connected to the first guide pipe, the second conveying circulation pipeline is connected to the second guide pipe, and the third conveying circulation pipeline is connected to the third guide pipe; The heating mechanism also includes a high-pressure heater, a condensate tank, a demineralized water tank, and a deaerator; The inlet of the first conveying circulation pipeline is connected to the high-pressure heater, and the outlet of the first conveying circulation pipeline is connected to the deaerator. The high-pressure heater is used to provide water to the first conveying circulation pipeline. The inlet of the second conveying circulation pipeline is connected to the condensate tank, and the outlet of the second conveying circulation pipeline is connected to the deaerator. The condensate tank is used to provide water to the second conveying circulation pipeline. The inlet of the third conveying circulation pipeline is connected to the demineralized water tank, and the outlet of the third conveying circulation pipeline is connected to the deaerator. The demineralized water tank is used to provide water to the third conveying circulation pipeline.

5. The thermal power plant exhaust steam recovery system according to claim 3, characterized in that: The first guide tube is arranged in a spiral pattern in the upper heat recovery cavity, the second guide tube is arranged in a spiral pattern in the middle heat recovery cavity, and the third guide tube is arranged in a spiral pattern in the lower heat recovery cavity.

6. The thermal power plant exhaust steam recovery system according to claim 3, characterized in that: The heat recovery mechanism also includes multiple guide plates, which are staggered and spaced apart in the upper heat recovery cavity.

7. The thermal power plant exhaust steam recovery system according to any one of claims 3 to 6, characterized in that: The heat recovery mechanism further includes a buffer cavity, which is located on top of the upper heat recovery cavity and is connected to the upper heat recovery cavity. The buffer cavity is also connected to the exhaust pipe of the steam distribution cylinder via a pipeline.

8. The thermal power plant exhaust steam recovery system according to claim 4, characterized in that: The heat recovery mechanism also includes a condensate chamber; The condensate chamber is located at the bottom of the lower heat recovery chamber, and the condensate chamber is connected to the lower heat recovery chamber. The condensate chamber and the condensate tank are connected by a pipeline.

9. The thermal power plant exhaust steam recovery system according to claim 8, characterized in that: The thermal power plant exhaust steam recovery system also includes a control valve, which is installed on the pipeline between the condensate chamber and the condensate tank. The condensate chamber is installed at a higher height than the condensate tank.

10. The thermal power plant exhaust steam recovery system according to claim 1, characterized in that: The thermal power plant exhaust steam recovery system also includes a regulating valve, which is installed on the pipeline between the heat recovery mechanism and the exhaust pipe of the steam distribution cylinder.

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