A steam superheater
By setting up a mixing chamber and valves to control the process airflow path in the steam superheater, the problem of unstable temperature during the initial and long-term operation of the steam superheater was solved, achieving stable control of steam temperature and improved heat exchange efficiency.
Patent Information
- Application Number
- CN202522607893.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-09
- Publication Date
- 2026-11-06
- Estimated Expiration
- 2035-12-09
AI Technical Summary
Existing steam superheaters suffer from unstable heat exchange efficiency both during the initial stage of operation and after long-term operation, making it difficult to control the superheated steam temperature within the expected range, thus affecting steam quality and the stable operation of subsequent processes.
A steam superheater was designed, which sets up a heat exchange chamber and a steam chamber inside the shell, and forms a mixing chamber between the first inner cylinder section and the inner wall of the shell. The process gas flow path is controlled by valves to adjust the process gas volume and regulate the steam temperature. The design includes opening through holes and annular gaps on the first inner cylinder section to achieve process gas diversion and mixing.
Stable control of steam temperature was achieved, ensuring steam quality and stable operation of subsequent processes, and improving heat exchange efficiency and temperature control accuracy.
Smart Images
Figure CN224944747U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of chemical waste heat recovery technology, especially to the field of waste heat recovery in coal gasification methanation plants, and specifically to a steam superheater. Background Technology
[0002] Steam superheaters are key equipment in waste heat recovery systems of chemical plants. Their main function is to use waste heat from chemical production to heat saturated steam into superheated steam, thereby meeting the needs of subsequent processes. A steam superheater consists of an outer shell and a bundle of steam heat exchange tubes placed inside it. High-temperature flue gas flows outside the tubes, transferring heat to the steam flowing inside the tubes.
[0003] Existing steam superheaters typically employ a fixed flow channel structure. High-temperature process gas enters the superheater through the process gas inlet, flows through the shell side of the superheater and exchanges heat with the heat exchange tubes, transferring heat to the steam in the tubes before exiting through the process gas outlet. During this process, the steam is heated to the required superheated temperature. However, in the initial stages of superheater operation, when the heat exchange tube surfaces are clean and the fouling thermal resistance is zero, the heat exchange efficiency is excessively high, easily causing the produced superheated steam temperature to exceed the set value. After long-term operation, fouling increases the thermal resistance, resulting in insufficient heat exchange and the superheated steam temperature failing to meet process requirements. Furthermore, when production load fluctuates, the outlet steam temperature fluctuates significantly, exhibiting poor stability and making it difficult to stably control the steam temperature within the expected range, directly impacting steam quality and the stable operation of subsequent processes. Utility Model Content
[0004] The purpose of this invention is to provide a steam superheater for regulating the temperature of the steam discharged from the steam superheater, keeping the steam temperature stably within the expected range, and ensuring the stable operation of steam quality and subsequent processes.
[0005] To achieve the above objectives, this utility model provides the following technical solution: A steam superheater, comprising: The tube shell has a heat exchange chamber and a steam chamber arranged sequentially along its axial direction. The tube shell has a process gas inlet, a process gas outlet, a steam inlet, and a steam outlet. The process gas outlet is connected to the heat exchange chamber, and the steam inlet is connected to the steam chamber. The first inner cylinder section is fixedly installed inside the heat exchange cavity, and a mixing cavity is formed between the outer peripheral surface of the first inner cylinder section and the inner wall of the tube shell. The first inner cylinder section is provided with a first through hole and a process gas inlet. The second inner cylinder section is fixedly installed in the heat exchange cavity and communicates with the first inner cylinder section. A first annular gap is formed between the outer circumferential surface of the second inner cylinder section and the inner wall of the tube shell. The cross-sectional area of the first inner cylinder section perpendicular to the tube shell axis is smaller than the cross-sectional area of the second inner cylinder section. Tube sheet, which is fixedly installed inside the tube shell and sealed between the heat exchange chamber and the steam chamber, has heat exchange tube mounting holes. The heat exchange tube assembly is fixedly installed in the second inner cylinder section. The heat exchange tubes in the heat exchange tube assembly have an inlet end and an outlet end. The inlet end is connected to the steam chamber, and the outlet end is connected to the steam outlet. The heat exchange tubes in the heat exchange tube assembly are all sealed and installed in the heat exchange tube mounting hole. A valve is installed at the first through hole and is used to control the opening and closing of the inner cavity of the first inner cylinder section and the heat exchange cavity.
[0006] Optionally, in the above-mentioned steam superheater, the first through hole is opened on the outer peripheral surface of the first inner cylinder section, and the process gas inlet is opened on the end face of the first inner cylinder section away from the second inner cylinder section.
[0007] Optionally, in the above-mentioned steam superheater, the ratio of the cross-sectional area of the first inner cylinder section perpendicular to the shell axis to the cross-sectional area of the shell is 1 / 4 to 1 / 2.
[0008] Optionally, in the above-mentioned steam superheater, a heat insulation layer is provided on the inner wall of the shell corresponding to the mixing chamber. The heat insulation layer is arranged around the circumference of the shell and extends along the axial direction of the shell.
[0009] Optionally, in the above-mentioned steam superheater, a second through hole is provided on the tube shell, and a drive mechanism is sealed at the second through hole. The drive mechanism includes an operating end located outside the heat exchange chamber and a drive end connected to the valve, which is used to drive the opening degree of the valve.
[0010] Optionally, in the above-mentioned steam superheater, the heat exchange tubes in the heat exchange tube group include an inner tube and an outer tube. The outer tube is coaxially sleeved outside the inner tube, and a second annular gap is formed between the outer tube and the inner tube. The outer tube has a closed end and an air inlet end that are arranged opposite to each other. The air inlet end has a third through hole that connects the steam inlet and the second annular gap. The inner tube includes two intersecting ends, one of which is connected to the steam outlet.
[0011] Optionally, in the above-mentioned steam superheater, the outer wall of the outer tube is also provided with fins, the fins are inclined on the outer wall of the outer tube, and the inclination direction of the fins intersects with the axial direction of the heat exchange tube.
[0012] Optionally, in the above-mentioned steam superheater, a protective cover is fixedly provided on the outside of the closed end. The protective cover has two ends fixed on the outside of the closed end, and the protective cover and the outer sleeve form a closed cavity, with the closed end located inside the closed cavity.
[0013] Optionally, in the above-mentioned steam superheater, the steam superheater further includes a central steam collector pipe, which is disposed in the steam chamber, and the two ends of the central steam collector pipe are respectively connected to the outlet end of the heat exchange tube group and the steam outlet.
[0014] Optionally, in the above-mentioned steam superheater, the steam superheater further includes multiple baffles, which are alternately and spaced apart and fixed in the second inner cylinder section along the axial direction of the shell.
[0015] Compared with the prior art, the steam superheater provided in this application has a heat exchange chamber and a steam chamber arranged sequentially along its axial direction inside the tube shell. A process gas outlet communicating with the heat exchange chamber and a steam inlet communicating with the steam chamber are correspondingly provided on the tube shell. A first inner cylinder section is fixedly disposed within the heat exchange chamber, and a mixing cavity is formed between the outer circumferential surface of the first inner cylinder section and the inner wall of the tube shell. A first through hole and a process gas inlet are provided on the first inner cylinder section. A second inner cylinder section is fixedly disposed within the heat exchange chamber and communicates with the first inner cylinder section. The outer circumferential surface of the second inner cylinder section is connected to the inner wall of the tube shell. A first annular gap is formed between the inner walls of the shell. The cross-sectional area of the first inner cylinder section perpendicular to the shell axis is smaller than that of the second inner cylinder section. The tube sheet is fixed inside the shell and seals the heat exchange chamber and the steam chamber. A heat exchange tube mounting hole is provided on the tube sheet. The heat exchange tube group is fixed in the second inner cylinder section. Each heat exchange tube is sealed and installed in the heat exchange tube mounting hole. The inlet end of the heat exchange tube is connected to the steam chamber, and the outlet end is connected to the steam outlet. A valve is provided at the first through hole to control the opening and closing between the inner cavity of the first inner cylinder section and the heat exchange chamber.
[0016] During operation: Process gas enters the first inner cylinder section through the process gas inlet, flows through the heat exchange tube assembly in the connected second inner cylinder section for heat exchange, and its temperature decreases. It then flows from the second inner cylinder section into the first annular gap until it exits from the process gas outlet. When it is necessary to lower the temperature of the superheated steam at the steam outlet, the valve is opened and its opening degree is adjusted, allowing some unexchanged process gas to flow out from the first through-hole and enter the mixing chamber. At this time, the amount of process gas entering the second inner cylinder section decreases, thus reducing the heat exchange between the process gas and the steam in the heat exchange tubes, achieving the effect of lowering the steam temperature. When it is not necessary to regulate the superheated steam at the steam outlet, the valve is closed. This setup, by adjusting the valve opening, regulates the amount of process gas flowing into the heat exchange tube assembly, thereby regulating the amount of process gas exchanging heat with the steam. When the valve opening increases, the amount of process gas exchanging heat with the steam decreases, and the steam temperature decreases. Specifically, when the valve remains open, a portion of the unheated process gas flows out from the first through-hole and enters the mixing chamber, while the other portion of the process gas exchanges heat with the heat exchange tube assembly through the second inner cylinder section. After heat exchange, it flows out from the second inner cylinder section into the first annular gap and then into the mixing chamber to mix with the higher-temperature unheated process gas. The mixed process gas is then discharged from the process gas outlet. Furthermore, the cross-sectional area of the first inner cylinder section perpendicular to the shell axis is smaller than that of the second inner cylinder section, creating a sufficiently large mixing chamber between the first inner cylinder section and the inner wall of the shell, which facilitates uniform mixing of the two process gas streams. With this configuration, the amount of process gas exchanging heat with the steam at the heat exchange tube assembly can be adjusted by regulating the valve opening, thereby stably controlling the steam temperature within the expected range and ensuring steam quality and stable operation of subsequent processes. Attached Figure Description
[0017] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 A schematic diagram of the overall structure of a steam superheater provided in an embodiment of this utility model; Figure 2 A schematic diagram of the overall structure of a steam superheater provided for another embodiment of this utility model; Figure 3 A schematic diagram of the overall structure of the heat exchange tube of a steam superheater provided in this embodiment of the present invention; Figure 4 This is a partially enlarged schematic diagram of the heat exchange tube of a steam superheater provided in an embodiment of the present invention.
[0018] Reference numerals: 100 is the tube shell, 110 is the heat exchange chamber, 111 is the process gas inlet, 112 is the process gas outlet, 120 is the steam chamber, 121 is the steam inlet, 122 is the steam outlet, 130 is the insulation layer, 140 is the second through hole, 210 is the first inner cylinder section, 220 is the second inner cylinder section, 230 is the first through hole, 240 is the mixing chamber, 300 is the first annular gap, 400 is the tube sheet, 500 is the heat exchange tube assembly, 600 is the heat exchange tube, 610 is the inner sleeve, 620 is the outer sleeve, 621 is the fin, 622 is the protective cover, 700 is the valve, 800 is the second annular gap, and 900 is the central steam collector. Detailed Implementation
[0019] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0020] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.
[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.
[0022] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0024] like Figure 1 As shown, the steam superheater provided in this embodiment of the present invention includes a shell 100, a first inner cylinder section 210, a second inner cylinder section 220, a tube sheet 400, a heat exchange tube assembly 500, and a valve 700. The shell 100 contains a heat exchange chamber 110 and a steam chamber 120 arranged sequentially along its axial direction. The shell 100 has a process gas inlet 111, a process gas outlet 112, a steam inlet 121, and a steam outlet 122. The process gas outlet 112 communicates with the heat exchange chamber 110, and the steam inlet 121 communicates with the steam chamber 120. The first inner cylinder section 210 is fixedly disposed within the heat exchange chamber 110, and a mixing cavity 240 is formed between the outer circumferential surface of the first inner cylinder section 210 and the inner wall of the shell 100. The first inner cylinder section 210 has a first through hole 230 and a process gas inlet 111. The second inner cylinder section 220 is fixedly disposed within the heat exchange chamber 110 and communicates with the first inner cylinder section 120. The cylindrical section 210 is connected, and a first annular gap 300 is formed between the outer peripheral surface of the second inner cylindrical section 220 and the inner wall of the shell 100. The cross-sectional area of the first inner cylindrical section 210 perpendicular to the axial direction of the shell 100 is smaller than the cross-sectional area of the second inner cylindrical section 220. The tube sheet 400 is fixedly installed inside the shell 100 and sealed between the heat exchange chamber 110 and the steam chamber 120. The tube sheet 400 has heat exchange tube mounting holes. The heat exchange tube group 500 is fixedly installed in the second inner cylindrical section 220. The heat exchange tube 600 in the heat exchange tube group 500 has an inlet end and an outlet end. The inlet end is connected to the steam chamber 120, and the outlet end is connected to the steam outlet 122. The heat exchange tubes 600 in the heat exchange tube group 500 are all sealed and installed in the heat exchange tube mounting holes. The valve 700 is provided at the first through hole 230 and is used to control the opening and closing of the inner cavity of the first inner cylindrical section 210 and the heat exchange chamber 110.
[0025] In the steam superheater provided in this application, a heat exchange chamber 110 and a steam chamber 120 are sequentially arranged along the axial direction inside the shell 100. A process gas outlet 112 communicating with the heat exchange chamber 110 and a steam inlet 121 communicating with the steam chamber 120 are correspondingly provided on the shell 100. A first inner cylinder section 210 is fixedly disposed within the heat exchange chamber 110, and a mixing cavity 240 is formed between the outer circumferential surface of the first inner cylinder section 210 and the inner wall of the shell 100. A first through hole 230 and a process gas inlet 111 are provided on the first inner cylinder section 210. A second inner cylinder section 220 is fixedly disposed within the heat exchange chamber 110 and is connected to the first inner cylinder section 220. 210 is connected, and a first annular gap 300 is formed between the outer peripheral surface of the second inner cylinder section 220 and the inner wall of the shell 100. The cross-sectional area of the first inner cylinder section 210 perpendicular to the axial direction of the shell 100 is smaller than the cross-sectional area of the second inner cylinder section 220. The heat exchange tube group 500 is fixed in the second inner cylinder section 220, and each heat exchange tube 600 is sealed and installed in the heat exchange tube mounting hole. The air inlet end of the heat exchange tube 600 is connected to the steam chamber 120, and the air outlet end is connected to the steam outlet 122. The valve 700 is set at the first through hole 230 and is used to control the opening and closing between the inner cavity of the first inner cylinder section 210 and the heat exchange chamber 110.
[0026] During operation: Process gas enters the first inner cylinder section 210 through process gas inlet 111, flows through the heat exchange tube assembly 500 in the connected second inner cylinder section 220 for heat exchange, and its temperature decreases. It then flows from the second inner cylinder section 220 into the first annular gap 300 until it is discharged from the process gas outlet 112. When it is necessary to reduce the temperature of the superheated steam at the steam outlet, valve 700 is opened and its opening degree is adjusted, allowing some unexchanged process gas to flow out from the first through hole 230 and enter the mixing chamber 240. At this time, the amount of process gas entering the second inner cylinder section 220 decreases, thus reducing the heat exchange between the process gas and the steam in the heat exchange tubes, achieving the effect of lowering the steam temperature. With this setup, by adjusting the opening degree of valve 700, the amount of process gas flowing into the heat exchange tube assembly is adjusted, thereby adjusting the amount of process gas exchanging heat with the steam. When the opening degree of valve 700 increases, the amount of process gas exchanging heat with the steam decreases, and the steam temperature decreases. Specifically, when valve 700 remains open, a portion of the unheated process gas flows out from the first through-hole 230 and enters the mixing chamber 240. Another portion of the process gas passes through the second inner cylinder section 220 and exchanges heat with the heat exchange tube assembly 500. After heat exchange, it flows out from the second inner cylinder section 220 into the first annular gap 300 and then flows into the mixing chamber 240 to mix with the unheated process gas. The mixed process gas is then discharged from the process gas outlet 112. Furthermore, the cross-sectional area of the first inner cylinder section 210 perpendicular to the axial direction of the shell 100 is smaller than that of the second inner cylinder section 220, creating a sufficiently large mixing chamber 240 between the first inner cylinder section 210 and the inner wall of the shell 100, which facilitates uniform mixing of the two process gas streams. With this setup, the flow rate of process gas entering the heat exchange tube assembly at point 500 for heat exchange with steam can be adjusted by regulating the valve opening at 700 degrees, thereby stably controlling the steam temperature within the expected range and ensuring the stable operation of steam quality and subsequent processes.
[0027] The first inner cylinder section 210 with a smaller cross-section is used to introduce and guide process gas, and the first through hole 230 opened on it is used for flow diversion; the second inner cylinder section 220 with a larger cross-section is used to accommodate the heat exchange tube assembly 500 and form a first annular gap 300 with the tube shell 100. High-temperature process gas enters the first inner cylinder section 210 from the process gas inlet 111. Due to the small flow cross-section of the first inner cylinder section 210, the airflow velocity is high. This makes it easier for the airflow diverted from the first through hole 230 into the mixing chamber 240 to be drawn out and form a stable bypass when the valve 700 is opened. In addition, the small cross-section of the first inner cylinder section 210 allows for a larger space between it and the shell 100, which can provide a larger mixing space for the process gas, increase the uniformity of mixing, and improve the accuracy of temperature control. A portion of the process gas enters the second inner cylinder section 220 with an enlarged cross-section, where the flow velocity decreases and it undergoes sufficient heat exchange with the heat exchange tube group 500 arranged in the second inner cylinder section 220. After heat exchange, part of the process gas flows from the second inner cylinder section 220 into the first annular gap 300 and into the mixing chamber 240 formed between the first inner cylinder section 210 and the shell 100, where it mixes with the unexchanged process gas flowing out from the first through hole 230. This configuration, with its variable cross-section design of the first inner cylinder section 210 and the second inner cylinder section 220, ensures that the process gas flowing through the first inner cylinder section 210 maintains a high flow velocity, facilitating better airflow out of the first through-hole 230. Furthermore, the large space design of the second inner cylinder section 220 guarantees high efficiency and stability in the heat exchange process, thereby enabling more precise airflow distribution and temperature control. In addition, the cross-sectional shape of the first inner cylinder section 210 and the second inner cylinder section 220 can be circular to adapt to different installation spaces and process requirements.
[0028] It is understood that the steam superheater provided in this embodiment can not only regulate the temperature of the outlet steam, but also regulate the temperature of the outlet process gas. When it is necessary to regulate the temperature of the outlet process gas, by increasing the opening of valve 700, a portion of the high-temperature process gas that has not undergone heat exchange enters the heat exchange chamber 110 through the first through hole 230, while another portion of the high-temperature process gas that has undergone heat exchange in the heat exchange tube group 500 flows through the first annular gap 300 to the mixing chamber 240 and mixes with the high-temperature process gas that has not undergone heat exchange. The two are mixed in proportion by adjusting the opening of valve 700, thereby achieving the regulation of the temperature of the outlet process gas.
[0029] As one possible implementation, such as Figure 1 As shown, the first through hole 230 is opened on the outer peripheral surface of the first inner cylinder section 210, and the process gas inlet 111 is opened on the end face of the first inner cylinder section 210 away from the second inner cylinder section 220.
[0030] Specifically, one end face of the first inner cylinder section 210 serves as the inlet for the process gas, and a first through hole 230 for flow diversion is formed on its outer circumferential surface. In practice, high-temperature process gas enters axially from the process gas inlet 111 on the end face of the first inner cylinder section 210. A portion of the gas flow, when passing through the first through hole 230, can flow radially out through the first through hole 230 on the side wall under the control of the valve 700, forming a bypass gas flow that enters the mixing cavity 240 between the first inner cylinder section 210 and the shell 100; the other portion of the process gas continues to flow axially into the second inner cylinder section 220 for heat exchange. This arrangement, with the process gas inlet 111 and the first through hole 230 respectively located on mutually perpendicular end faces and outer circumferential surfaces, ensures that the mainstream direction of the process gas flow is axial, resulting in lower flow resistance. Simultaneously, lateral flow diversion from the outer circumferential surface facilitates the separation of the bypass gas flow from the mainstream with lower flow resistance, and allows the valve 700 to be installed on the side of the cylinder, facilitating the operation and maintenance of the valve 700.
[0031] In other embodiments, such as Figure 2 As shown, the first through hole 230 is formed on the end face of the first inner cylinder section 210 away from the second inner cylinder section 220, and the process gas inlet 111 is formed on the outer peripheral surface of the first inner cylinder section 210. In the structure of this embodiment, the process gas inlet 111 is provided on the outer peripheral surface of the first inner cylinder section 210, and the first through hole 230 for gas flow diversion is provided on the other end face of the first inner cylinder section 210 opposite to the second inner cylinder section 220. In specific implementation, high-temperature process gas enters the first inner cylinder section 210 radially from the process gas inlet 111 on the side wall of the first inner cylinder section 210. When it comes into contact with the side wall opposite to the process gas inlet 111 inside the cylinder, the process gas splits. Part of the process gas flows toward the second inner cylinder section 220, and part of the process gas flows away from the second inner cylinder section 220 (that is, toward the first through hole 230). When the process gas flowing toward the first through hole 230 reaches the first through hole 230, by adjusting the opening of the valve 700 set on the end face, part of the gas flow can flow directly axially out of the first through hole 230 on the end face and enter the mixing cavity 240 formed by the outer peripheral surface of the first inner cylinder section 210 and the inner wall of the tube shell 100 as a bypass gas flow. The other part of the process gas flows into the heat exchange tube group 500 of the second inner cylinder section 220 for heat exchange. With this configuration, the process gas enters radially and completes the flow direction change within the first inner cylinder section 210, giving the gas a clear axial flow direction when flowing towards the end face of the first inner cylinder section 210. This is beneficial for achieving stable airflow distribution at the end face. Diverting the flow from the end face allows the bypass airflow direction to be consistent with the mainstream direction, resulting in smoother flow and less pressure loss.
[0032] As one possible implementation, such as Figure 1 As shown, the ratio of the cross-sectional area of the first inner cylinder section 210 perpendicular to the axial direction of the shell 100 to the cross-sectional area of the shell 100 is 1 / 4 to 1 / 2.
[0033] Specifically, the ratio of the cross-sectional area of the first inner cylinder section 210 perpendicular to the axial direction of the shell 100 to the cross-sectional area of the shell 100 is 1 / 4 to 1 / 2, specifically 1 / 4, 1 / 3, 1 / 2, or any ratio within this range. Specifically, the flow cross-section of the first inner cylinder section 210 is smaller than the cross-section of its outer shell 100, so that a sufficiently large mixing cavity 240 is formed between the outer wall surface of the first inner cylinder section 210 and the inner wall surface of the shell 100. In specific implementation, when the valve 700 is opened, a portion of the high-temperature process gas flows out from the first through-hole 230 of the first inner cylinder section 210 and enters the mixing cavity 240 formed between the outer peripheral surface of the first inner cylinder section 210 and the shell 100; simultaneously, the low-temperature process gas flowing out from the second inner cylinder section 220 and having undergone heat exchange also merges into the mixing cavity 240. Because the cross-sectional area of the mixing chamber 240 is larger than the flow area of the inner cavity of the first inner cylinder section 210, it provides a spacious mixing space for the two process gases with different temperatures. This design ensures that the mixing space is large enough, avoiding local eddies or uneven mixing caused by airflow impact due to a narrow mixing space. The two process gases can be fully mixed in this larger space, thereby achieving a uniform temperature field before flowing out of the process gas outlet 112. This effectively solves the problem that uneven temperature may affect the stability of subsequent processes, ensuring the uniformity and controllability of the outlet process gas temperature.
[0034] In some embodiments, such as Figure 1 As shown, an expansion joint is provided axially in the first inner cylinder section 210. The expansion joint is integrated into the cylinder body of the first inner cylinder section 210 and is an axially expandable bellows. This expansion joint is directly connected to the first inner cylinder section 210 via connecting flanges at both ends or by welding. During operation, when the temperature changes, the first inner cylinder section 210 will tend to displace axially due to thermal expansion and contraction. At this time, the expansion joint, due to its bellows structure, can undergo compression or tensile deformation, actively absorbing and compensating for the axial dimensional changes caused by temperature variations.
[0035] As one possible implementation, such as Figure 1 and Figure 2 As shown, a heat insulation layer 130 is provided on the inner wall of the shell 100 corresponding to the mixing chamber 240. The heat insulation layer 130 is arranged around the circumference of the shell 100 and extends along the axial direction of the shell 100.
[0036] A heat insulation layer 130, composed of heat insulation material, is disposed in a specific area on the inner wall of the shell 100, corresponding to the mixing chamber 240. This heat insulation layer 130 is a complete annular structure surrounding the inner wall of the shell 100, and also has a certain length of coverage along the axial direction of the shell 100. In practice, when valve 700 is opened, and high-temperature process gas flows out from the first through-hole 230 and impacts the inner wall of the shell 100, the heat insulation layer 130 covering the inner wall of the shell 100 directly bears the impact of this high-temperature process gas. As a thermal barrier, the heat insulation layer 130 effectively blocks the transfer of high-temperature heat to the inner wall of the shell 100. This arrangement, with the heat insulation layer 130 placed in the area impacted by the high-temperature process gas flow, protects the shell 100 material from overheating, preventing material strength degradation, creep, or other damage caused by prolonged exposure to high temperatures. This ensures the structural safety and reliability of the equipment during long-term operation and extends the service life of the shell 100.
[0037] As one possible implementation, such as Figure 1 As shown, a second through hole 140 is provided on the shell 100, and a driving mechanism is sealed at the second through hole 140. The driving mechanism includes an operating end located outside the heat exchange chamber 110 and a driving end connected to the valve 700, which is used to drive the opening degree of the valve 700.
[0038] Specifically, a second through hole 140 corresponding to the position of the first through hole 230 is provided on the wall of the shell 100. The drive mechanism is installed on the shell 100 and has an operating end located outside the shell 100 and a drive end located inside the shell 100. The drive end is connected to the valve 700. When it is necessary to adjust the temperature of the process gas outlet 112, the operator can operate the operating end of the drive mechanism to drive the valve 700 to open or close. With this configuration, by setting a sealed drive mechanism on the shell 100, direct and reliable control of the internal valve 700 from the outside is achieved without damaging the overall seal of the steam superheater and the internal process flow. This allows for real-time adjustment of the bypass gas flow rate according to process requirements, thereby achieving precise control of the outlet process gas temperature.
[0039] In some embodiments, valve 700 is a plunger valve. A cylindrical structure is provided on the outer peripheral surface of the first inner cylinder section 210. The axial direction of the cylindrical structure is perpendicular to the axial direction of the first inner cylinder section 210, and the cylindrical structure is connected to the first inner cylinder section 210. The plunger valve is disposed inside the cylindrical structure. By adjusting the drive mechanism, the plunger valve is pulled up or pushed down to adjust the opening degree of the plunger valve, thereby changing the flow rate of the high-temperature process gas flowing out at this location, thus adjusting the flow ratio of the mixed process gas, and thereby regulating the temperature of the outlet process gas. Optionally, valve 700 can be a ball valve or a butterfly valve.
[0040] As one possible implementation, such as Figure 3 As shown, the heat exchange tube 600 in the heat exchange tube assembly 500 includes an inner sleeve 610 and an outer sleeve 620. The outer sleeve 620 is coaxially sleeved outside the inner sleeve 610, and a second annular gap 800 is formed between the outer sleeve 620 and the inner sleeve 610. The outer sleeve 620 has a closed end and an air inlet end that are arranged opposite to each other. The air inlet end has a third through hole that connects to the steam inlet 121 and the second annular gap 800. The inner sleeve 610 includes two through ends, one of which is connected to the steam outlet 122.
[0041] Specifically, the heat exchange tubes 600 of the second heat exchange tube group 500 adopt a double-layer sleeve design. The outer sleeve 620 is coaxially sleeved around the inner sleeve 610, forming a second annular gap 800. A steam inlet 121 is opened at the other end, connecting to the steam chamber 120. The inner sleeve 610 has a through-hole design, with one end extending to the closed end and the other end connecting to the steam outlet 122. During operation: steam enters the second annular gap 800 from the steam chamber 120 through the inlet end of the outer sleeve 620. The steam flows axially along the heat exchange tube 600 to the closed end, then turns and enters the inner sleeve 610, finally exiting from the steam outlet 122. This configuration extends the steam flow path by forming a second annular gap 800 between the inner sleeve 610 and the outer sleeve 620, improving heat exchange efficiency.
[0042] Furthermore, such as Figure 3 As shown, the outer wall of the outer jacket 620 is also provided with fins 621. The fins 621 are inclined on the outer wall of the outer jacket 620, and the inclination direction of the fins 621 intersects the axial direction of the heat exchange tube 600. This arrangement enhances the rigidity of the heat exchange tube 600, increases the heat exchange area, and improves the heat exchange efficiency.
[0043] Furthermore, such as Figure 4 As shown, a protective cover 622 is fixedly installed on the outside of the closed end. The protective cover 622 has two ends fixed on the outside of the closed end, and the protective cover 622 and the outer sleeve 620 form a closed cavity, with the closed end located inside the closed cavity.
[0044] With this configuration, the protective cover 622 is placed at the end of the heat exchange tube 600 that directly faces the process gas. When the process gas flows outside the tube, the protective cover 622 isolates the high-temperature gas flow from directly impacting the closed end, thus minimizing the heat-affected end of the heat exchange tube 600 and reducing the high-temperature erosion of the heat exchange tube 600 by the high-temperature process gas.
[0045] Furthermore, such as Figure 1 As shown, the steam superheater also includes a central steam collector 900, which is located inside the steam chamber 120. The two ends of the central steam collector 900 are connected to the outlet end of the heat exchange tube group 500 and the steam outlet 122, respectively.
[0046] During operation, steam enters the steam chamber 120 through the steam inlet 121, then enters the heat exchange tube 600 through the steam inlet 121 end at the outer sleeve 620. After participating in heat exchange in the second annular gap 800, it is injected into the central steam collecting pipe 900 through the inner sleeve 610, and then reaches the steam outlet 122 from the central steam collecting pipe 900 for discharge and collection. The central steam collecting pipe 900 ensures that the superheated steam after heat exchange is collected centrally, increasing collection efficiency.
[0047] As one possible implementation, the steam superheater also includes multiple baffles, which are alternately and spaced apart within the second inner cylinder section along the axial direction of the tube shell. By setting the baffles, the airflow is forced to change direction, extending the residence time of the process airflow within the second inner cylinder section 220. This provides a longer path for the process airflow to fully exchange heat with the heat exchange tube assembly 500, thereby improving the heat exchange effect.
[0048] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.
[0049] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.
Claims
1. A steam superheater characterized by, include: The tube shell has a heat exchange chamber and a steam chamber arranged sequentially along its axial direction. The tube shell has a process gas inlet, a process gas outlet, a steam inlet, and a steam outlet. The process gas outlet is connected to the heat exchange chamber, and the steam inlet is connected to the steam chamber. The first inner cylinder section is fixedly disposed in the heat exchange cavity, and a mixing cavity is formed between the outer peripheral surface of the first inner cylinder section and the inner wall of the shell. The first inner cylinder section is provided with a first through hole and the process gas inlet. The second inner cylinder section is fixedly disposed in the heat exchange cavity and communicates with the first inner cylinder section. A first annular gap is formed between the outer peripheral surface of the second inner cylinder section and the inner wall of the tube shell. The cross-sectional area of the first inner cylinder section perpendicular to the axial direction of the tube shell is smaller than the cross-sectional area of the second inner cylinder section. A tube sheet is fixedly disposed inside the tube shell and sealed between the heat exchange chamber and the steam chamber. The tube sheet is provided with heat exchange tube mounting holes. A heat exchange tube assembly is fixedly installed in the second inner cylinder section. The heat exchange tubes in the heat exchange tube assembly have an inlet end and an outlet end. The inlet end is connected to the steam chamber, and the outlet end is connected to the steam outlet. All heat exchange tubes in the heat exchange tube assembly are sealed and installed in the heat exchange tube mounting hole. A valve is provided at the first through hole and is used to control the connection and disconnection between the inner cavity of the first inner cylinder section and the heat exchange cavity.
2. The steam superheater of claim 1, wherein, The first through hole is opened on the outer peripheral surface of the first inner cylinder section, and the process gas inlet is opened on the end face of the first inner cylinder section away from the second inner cylinder section.
3. The steam superheater according to claim 1, characterized in that, The ratio of the cross-sectional area of the first inner cylinder section perpendicular to the axial direction of the shell to the cross-sectional area of the shell is 1 / 4 to 1 / 2.
4. The steam superheater according to claim 1, characterized in that, A heat insulation layer is provided on the inner wall of the tube shell corresponding to the mixing cavity. The heat insulation layer is arranged around the circumference of the tube shell and extends along the axial direction of the tube shell.
5. The steam superheater according to claim 1, characterized in that, The tube shell has a second through hole, and a driving mechanism is sealed at the second through hole. The driving mechanism includes an operating end located outside the heat exchange chamber and a driving end connected to the valve, which is used to drive the opening degree of the valve.
6. The steam superheater according to claim 1, characterized in that, The heat exchange tubes in the heat exchange tube assembly include an inner tube and an outer tube. The outer tube is coaxially sleeved outside the inner tube, and a second annular gap is formed between the outer tube and the inner tube. The outer tube has a closed end and an air inlet end that are arranged opposite to each other. The air inlet end has a third through hole that connects the steam inlet and the second annular gap. The inner tube includes two through ends, one of which is connected to the steam outlet.
7. The steam superheater according to claim 6, characterized in that, The outer wall of the outer jacket is also provided with fins, which are inclinedly disposed on the outer wall of the outer jacket, and the inclination direction of the fins intersects with the axial direction of the heat exchange tube.
8. The steam superheater according to claim 6, characterized in that, A protective cover is fixedly provided on the outside of the closed end. The protective cover has two ends fixed on the outside of the closed end, and the protective cover and the outer sleeve form a closed cavity, with the closed end located inside the closed cavity.
9. The steam superheater according to claim 6, characterized in that, The steam superheater also includes a central steam collector pipe, which is disposed in the steam chamber. The two ends of the central steam collector pipe are respectively connected to the outlet end of the heat exchange tube assembly and the steam outlet.
10. The steam superheater according to claim 1, characterized in that, The steam superheater also includes a plurality of baffles, which are alternately and spaced apart within the second inner cylinder section along the axial direction of the shell.