High-efficiency vertical packed column gas-gas heat exchanger

Abstract

The utility model discloses a kind of efficient vertical packing gland gas heat exchangers, including pressure-bearing shell, for conveying high-temperature gas's pipe, for conveying low-temperature gas's shell and heat exchange part. Pipe is blocked by heat insulation sleeve pipe and heat insulation layer and is transmitted to shell wall and shell course upper cavity, upper tube sheet can be moved up and down to compensate thermal expansion difference, shell course sets up packing gland sealing and solves thermal displacement compensation problem, support cylinder and annular baffle cooperation guide low-temperature gas to flow through all heat exchange area, improve heat exchange efficiency;Baffle plate enhances shell course gas turbulence, and guide distribution blade optimizes upper cavity area airflow distribution. The utility model is through multiple heat insulation, displacement compensation and fluid path optimization design, significantly improve heat exchange efficiency, prolong the life of equipment, reduce maintenance cost, with wide application prospect.

Description

Technical Field

[0001] This utility model relates to a gas-to-gas heat exchanger, and more particularly to a high-efficiency vertical stuffed gland gas-to-gas heat exchanger, suitable for heat exchange between high-temperature gases and low-temperature gases. This heat exchanger is widely used in industries such as chemical, petroleum, metallurgy, and power, and has significant application value, especially in high-temperature flue gas waste heat recovery and industrial furnace exhaust gas treatment. Background Technology

[0002] Gas-to-gas heat exchangers are devices used for heat exchange between gases, and are widely used in industrial production processes such as waste heat recovery and exhaust gas treatment. Existing gas-to-gas heat exchangers are prone to localized overheating at the high-temperature gas inlet, leading to material aging, shortened lifespan, and even safety hazards. Furthermore, traditional gas-to-gas heat exchangers have complex sealing structures between the tube and shell sides, resulting in high maintenance costs, and are prone to leakage under conditions of high temperature and high pressure differences.

[0003] While various gas-to-gas heat exchanger designs exist in the prior art, such as the high-temperature gas-to-gas heat exchangers proposed in patents CN219714099U and CN112902710A, the durability and heat exchange efficiency of these designs under high-temperature environments still need improvement. Furthermore, existing gas-to-gas heat exchangers often employ complex flange connections or welding methods in their sealing structures, which not only increases manufacturing costs but also makes equipment maintenance and repair difficult. Therefore, there is an urgent need for a new type of high-temperature gas-to-gas heat exchanger that can maintain efficient heat exchange under high-temperature environments while possessing good durability and structural stability. Utility Model Content

[0004] The purpose of this invention is to provide a high-efficiency vertical stuffed box gas-to-gas heat exchanger to solve the problem of long-term operation of existing gas-to-gas heat exchangers under high-temperature conditions.

[0005] To achieve the above objectives, this utility model provides a high-efficiency vertical stuffing box gas-to-gas heat exchanger, comprising: a pressure-bearing shell 5, a tube side for transporting high-temperature gas, a shell side for transporting low-temperature gas, and a heat exchange section for heat exchange; the tube side includes a high-temperature gas inlet a, a heat insulation sleeve 4, a head 206, a heat insulation layer 207, and a cooling gas outlet b, wherein the high-temperature gas inlet a and the cooling gas outlet b are respectively located at the top and bottom ends of the tube side, the heat insulation layer 207 is located outside the head 206, the heat insulation sleeve 4 at least partially overlaps the heat insulation layer 207, the lower end of the head 206 is connected to an upper tube sheet 205, and the upper tube sheet 205 is movable vertically. The shell side includes a low-temperature gas inlet c, a heating gas outlet d, and a shell side cavity, all located on the side wall of the pressure-bearing shell 5. The shell side cavity above the upper tube sheet 205 is the upper cavity region. The heat exchange section includes a support cylinder 203 and a heat exchange tube bundle 202. The support cylinder 203 is located around the heat exchange tube bundle 202. An annular baffle 3 is provided in the annular gap between the pressure-bearing shell 5 and the support cylinder 203. The heat insulation sleeve 4 is located between the high-temperature gas inlet a and the end cap 206. The top end of the heat exchange tube bundle 202 is fixedly connected to the tube hole of the upper tube sheet 205. A gap is left between the support cylinder 203 and the upper tube sheet 205.

[0006] Preferably, a stuffing box seal 209 is provided on the outer side of the heat insulation sleeve 4.

[0007] Preferably, the heat insulation sleeve 4 includes a set bolt 41, a gasket 42, a tray 43, a heat insulation layer 44, and a flared tube 45, wherein the heat insulation layer 44 is disposed on the outer layer of the heat insulation sleeve 4.

[0008] Preferably, the high-temperature gas inlet a includes a flange, the tray 43 has a groove on the flange of the high-temperature gas inlet a, a gasket 42 is placed between the tray 43 and the flange, and the gasket is tightened by a set bolt 41.

[0009] Preferably, at least one baffle 204 is provided inside the support cylinder 203 to change the gas flow direction and velocity.

[0010] Preferably, the baffle 204 is an arc-shaped baffle or a baffle rod.

[0011] Preferably, the heating gas outlet d is located on the side wall of the pressure-bearing housing 5 at a position corresponding to the upper cavity region.

[0012] Preferably, the annular baffle 3 includes a bolt 31, a pressure strip 32, a retaining ring 33, and a sealing strip 34. The pressure strip 32 and the retaining ring 33 are fastened together by the bolt 31, and the sealing strip 34 is disposed between the pressure strip 32 and the pressure-bearing housing 5.

[0013] Preferably, the sealing strip 34 is composed of a thin steel plate with a thickness of 0.1 mm, and has 10 to 30 layers.

[0014] Preferably, a flow distribution blade 210 is provided on the inner wall of the upper cavity region.

[0015] Preferably, the end cap 206 is a conical end cap or an elliptical end cap 212.

[0016] Compared with the prior art, the present invention has the following technical effects:

[0017] By adding insulation layers, optimizing support cylinder design, and simplifying sealing structures, heat exchange efficiency has been significantly improved, equipment lifespan has been extended, and maintenance costs have been reduced. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the high-efficiency vertical stuffed box gas heat exchanger of this utility model;

[0019] Figure 2 This is a schematic diagram of the structure of the stuffing box seal 209 and the heat insulation sleeve 4 of this utility model;

[0020] Figure 3 This is a schematic diagram of the structure of the heat insulation sleeve 4 of this utility model;

[0021] Figure 4 This is a schematic diagram of the structure of the annular baffle 3 of this utility model.

[0022] Figure 5 This is a schematic diagram of the flow distribution blade 210 of this utility model.

[0023] Figure 6 This is a schematic diagram of the structure of the elliptical end cap of this utility model.

[0024] In the diagram, 1 is the lower tube box, 3 is the annular baffle, 4 is the heat insulation sleeve, 5 is the pressure-bearing shell, a is the high-temperature gas inlet, b is the cooling gas outlet, c is the low-temperature gas inlet, d is the heating gas outlet, e is the vent, f is the air vent, and g is the temperature measuring port; 201 is the lower tube sheet, 202 is the heat exchange tube bundle, 203 is the support cylinder, 204 is the baffle, 205 is the upper tube sheet, 206 is the end cap, 207 is the heat insulation layer, 208 is the short section, 209 is the stuffing box seal, 210 is the flow distribution vane, and 212 is the elliptical end cap; 31 is the bolt, 32 is the pressure strip, 33 is the retaining ring, and 34 is the sealing strip; 41 is the set bolt, 42 is the gasket, 43 is the tray, 44 is the heat insulation layer, and 45 is the bell tube. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate to understand the embodiments of the utility model described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a product or device comprising a series of units is not necessarily limited to those explicitly listed, but may include other units not explicitly listed or inherent to such product or device.

[0027] In this invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this invention and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0028] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this utility model according to the specific circumstances.

[0029] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; 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, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this utility model based on the specific circumstances.

[0030] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0031] Example

[0032] In existing technologies, gas-to-gas heat exchangers are widely used for heat exchange between high-temperature and low-temperature gases. However, they suffer from problems such as localized overheating under high-temperature conditions, complex sealing structures leading to maintenance difficulties, insufficient compensation for thermal expansion differences, and low heat exchange efficiency. Traditional heat exchangers often use flange connections or welded seals, which are prone to leakage under high-temperature and high-pressure differential environments, and lack effective insulation measures, resulting in a shortened equipment lifespan. Although existing designs improve heat exchange efficiency by adding insulation layers or optimizing tube bundle layouts, they fail to effectively resolve the contradiction between thermal expansion compensation and sealing reliability.

[0033] To address the aforementioned issues, the inventors discovered that localized overheating originates from direct contact between high-temperature gas and the shell wall, while seal failure is related to insufficient compensation for thermal expansion differences. By analyzing the heat conduction path, a double insulation structure was proposed at the tube-side inlet to block heat transfer, while a sliding structure was used to absorb the expansion difference. To address the uneven fluid distribution, a flow-guiding structure was proposed in the shell side to force gas flow through the heat exchange area. After structural optimization, fluid path control was determined through the cooperation of a support cylinder and an annular baffle, while thermal displacement compensation was addressed by combining a movable upper tube sheet and a stuffing box seal.

[0034] Therefore, this application proposes a high-efficiency vertical stuffed box gas-gas heat exchanger, such as... Figure 1 As shown, the system includes a pressure-bearing shell, tube side, shell side, and heat exchange section. The tube side includes a high-temperature gas inlet at the top and a cooling gas outlet at the bottom. A heat insulation layer is installed on the outside of the end caps, with the heat insulation sleeve partially overlapping the heat insulation layer. The shell side has a low-temperature gas inlet and a heating gas outlet on its sidewall, forming an upper cavity region above the upper tube sheet. The heat exchange section includes a support cylinder and a heat exchange tube bundle. An annular baffle is installed around the support cylinder. The top of the heat exchange tube bundle is fixedly connected to the tube holes of the upper tube sheet. The upper tube sheet can move up and down, and a gap is left between the support cylinder and the upper tube sheet.

[0035] The pressure-bearing shell refers to a sealed container that withstands internal pressure. It can be made of materials such as metal and formed into a cylindrical structure through welding, used to contain the tube-side and shell-side fluids. The tube-side refers to the high-temperature gas flow channel, specifically connected to an insulating sleeve through a high-temperature gas inlet. After passing through a diameter reduction head, the gas enters the heat exchange tube bundle. The bottom surface of the head connects to an upper tube sheet with perforations to achieve uniform gas distribution. The shell-side refers to the low-temperature gas flow space, specifically entering the annular gap between the pressure-bearing shell and the support cylinder through a side wall inlet. After being guided by an annular baffle, the gas enters the heat exchange area from the bottom of the support cylinder. The heat exchange section refers to the heat exchange functional unit, specifically using a support cylinder to fix the heat exchange tube bundle. Baffles can be installed inside the support cylinder to change the gas flow direction, and an annular baffle is installed in the annular gap between the support cylinder and the shell to prevent fluid short-circuiting. The insulating sleeve is the insulating structure wrapped inside the high-temperature gas inlet, specifically using set bolts to fix a tray and gasket, forming an overlapping area with the outer insulating layer of the head. An annular baffle is a sealing component that restricts the fluid path in the shell side. Specifically, it consists of multiple layers of thin steel plate sealing strips that are bolted between the pressure-bearing shell and the support cylinder to form an annular fluid barrier.

[0036] Specifically, high-temperature gas enters the insulation sleeve from the top inlet. Heat is blocked by the insulation sleeve and insulation layer, preventing overheating of the shell wall and upper shell-side cavity. After the gas diameter decreases at the end cap, it enters the heat exchange tube bundle uniformly. During its downward flow, it exchanges heat with the low-temperature gas in the shell side through the tube wall and is discharged from the bottom outlet after cooling. Low-temperature gas enters the shell annular gap from the side wall inlet. Constrained by the annular baffle, it must enter the heat exchange region from the bottom of the support cylinder. Under the action of the baffle, turbulence enhances heat exchange, and after heating, it is discharged from the side wall outlet in the upper cavity region. The support cylinder fixes the heat exchange tube bundle and guides the flow of the shell-side fluid. The gap between it and the upper tube sheet forms a channel for the heated gas to exit. The overlapping insulation layer of the end cap and insulation sleeve blocks heat conduction while providing compensation space for the thermal expansion difference between the tube and shell sides. The multi-layer sealing structure of the annular baffle maintains sealing reliability under pressure differential, preventing fluid short-circuiting. When the heat exchange tube bundle is working, it will produce a displacement difference due to the different thermal expansion. If the displacement difference is too large, it will cause damage to the equipment. Since the upper tube sheet can move up and down, it can move the end cap together, thereby compensating for the displacement difference between the heat exchange tube bundle and the shell.

[0037] Compared to existing technologies, traditional heat exchangers use a single insulation layer at the high-temperature inlet, which cannot effectively block radial heat conduction, resulting in excessively high temperatures in the shell wall and upper shell-side cavity. This solution, through the installation of an insulation sleeve and an insulation layer covering the end cap and insulation sleeve, increases thermal resistance and significantly reduces the shell temperature gradient. Traditionally, the shell-side fluid tends to flow directly from the annular gap to the outlet; this solution, through a combination of a support cylinder and annular baffle, guides the fluid through the entire heat exchange area, improving heat exchange efficiency.

[0038] Through the above technical solutions, this application effectively prevents localized overheating of the casing caused by high-temperature gases, extending the service life of the equipment. The simplified sealing structure reduces maintenance difficulty, and the thermal expansion compensation design avoids leakage risks. Optimized fluid distribution paths improve heat exchange efficiency and reduce energy loss. The annular baffle, in conjunction with the support cylinder, mitigates fluid short-circuiting, ensuring the heat exchange process proceeds fully.

[0039] like Figure 2 As shown, this application further proposes to install a stuffing box seal on the outside of the insulation sleeve.

[0040] Existing technologies mostly use fixed welding seals, which are prone to stress concentration during thermal expansion. This solution uses a stuffing box seal to achieve thermal displacement compensation in the shell side and avoid seal failure.

[0041] Specifically, the stuffing box seal is installed in the area of ​​concentrated thermal expansion difference between the shell side and the tube side. When the shell side expands due to heat, the packing layer allows for axial relative displacement between the insulation sleeve and the sealing cavity, maintaining the contact pressure at the sealing interface through the elastic deformation of the packing. The multiple layers of packing within the sealing cavity form a sealing structure after compression, effectively blocking gas leakage paths.

[0042] Compared to existing technologies, traditional sealing structures, which use flange bolt connections or welding for fixation, cannot compensate for structural stress caused by thermal expansion differences, making them prone to cracking of the sealing surface. This solution achieves thermal displacement compensation through a combination design of a stuffing box and an insulating sleeve.

[0043] Through the above technical solution, this application solves the problem of sealing failure caused by thermal expansion difference under high temperature conditions and reduces the maintenance frequency of the sealing structure.

[0044] like Figure 3 As shown, this application further proposes that the heat insulation sleeve includes a set bolt, a gasket, a tray, a heat insulation layer, and a flared tube, with the heat insulation layer disposed on the outer layer of the heat insulation sleeve.

[0045] The set bolt is a connecting component used to fix the tray and adjust the sealing pressure. It can be a threaded metal bolt. Tightening or loosening the bolt adjusts the compression of the gasket, thus compensating for deformation caused by thermal expansion. The gasket is a sealing element placed between the tray and the flange. It fills the gap between the contact surfaces through elastic deformation, preventing gas leakage. The tray is a supporting structure that bears the insulation layer and the flared tube. It is installed by embedding it into the flange through slots, distributing the weight of the insulation layer and maintaining structural stability. The insulation layer is the insulating material wrapped around the flared tube, which blocks heat transfer to the shell wall and upper shell cavity through its low thermal conductivity. The flared tube is a thin-walled pipe with flared ends, which can be made of rolled stainless steel sheet. The gradually flared structure reduces gas flow resistance and local eddies.

[0046] Specifically, when high-temperature gas enters through the inlet, it first flows through the flared tube, whose flared design reduces flow velocity and turbulence, preventing localized overheating. An insulation layer wraps around the outside of the flared tube, directly blocking heat transfer to the surrounding casing. The tray is secured by slots on the flange and tightened with set bolts, ensuring the stability of the insulation layer and the flared tube. A gasket is filled between the tray and the flange, undergoing elastic deformation during bolt tightening, achieving both a seal and allowing for thermal expansion displacement. When the equipment expands due to heat, the bolts can be adjusted to maintain the sealing pressure, preventing structural failure due to deformation. The thin-walled design of the flared tube reduces its weight and the load on the supporting structure, while the smooth transition between the flared end and the insulation sleeve further optimizes airflow distribution.

[0047] Compared to existing technologies, traditional thermal insulation sleeves often employ integral welding or complex sealing structures, making them difficult to adjust and maintain. For example, in existing solutions, the insulation layer is typically directly filled within a fixed sleeve, which cannot accommodate thermal expansion and deformation, easily leading to seal failure or insulation material cracking. This solution, however, utilizes adjustable bolt connections, independent tray supports, and elastic gaskets to allow the structure to expand freely at high temperatures while maintaining sealing performance. Furthermore, this solution employs a thin-walled flared tube with a gradually widening end, optimizing thermal stress distribution while ensuring strength.

[0048] Through the above technical solutions, this application effectively blocks the heat conduction of high-temperature gas to the shell wall, preventing local overheating damage to the equipment; the detachable bolt connection and tray structure simplify the installation and maintenance process, allowing the insulation layer to be replaced without overall disassembly; the thin-walled flared design of the horn tube reduces flow resistance, reduces material fatigue caused by gas scouring, and extends the service life of the insulation sleeve.

[0049] This application further proposes a high-temperature gas inlet including a flange, a tray with a groove on the flange of the high-temperature gas inlet, a gasket placed between the tray and the flange, and the gasket being tightened with set bolts.

[0050] Compared to existing technologies, traditional high-temperature inlets often employ integral welded structures or complex flange seals, resulting in thermal stress concentration and maintenance difficulties. This solution utilizes a detachable tray with a slotted flange, enabling rapid disassembly and maintenance while ensuring reliable sealing.

[0051] Through the above technical solution, this application effectively solves the problems of sealing failure and heat conduction at the high-temperature gas inlet, and significantly extends the continuous operation cycle of the equipment.

[0052] This application further proposes to install at least one baffle inside the support cylinder to change the gas flow direction and velocity.

[0053] The baffle plate refers to the airflow guiding structure installed inside the support cylinder. Specifically, it can be implemented using an arc-shaped baffle plate or a baffle rod, which forces the gas to change its flow direction through physical obstruction. The location of the baffle plate inside the support cylinder must cover the main gas flow area to ensure that the fluid is fully redirected within the cylinder, preventing unexchanged fluid from flowing out directly through the gaps.

[0054] Specifically, the arrangement of baffles within the support tube transforms the shell-side gas flow path from a single direction to a multi-directional flow. As gas flows past the baffles, the laminar flow is disrupted, creating turbulence. This enhanced turbulence allows for more thorough contact between the gas and the heat exchange tube bundle surface, increasing the frequency of thermal boundary layer disturbances. The minimum number of baffles ensures basic flow control functionality while providing a structural basis for multi-baffle combinations under different operating conditions. The optimized installation position of the baffles within the support tube allows for precise application to the main flow area of ​​the shell-side gas, preventing the fluid from directly short-circuiting through the support tube gaps without sufficient heat exchange.

[0055] Compared with existing technologies, this solution, by setting a basic structure with at least one baffle, not only ensures basic flow control functions, but also allows for increasing the number of baffles or adjusting the installation angle according to actual operating conditions, significantly improving the equipment's adaptability to different operating conditions.

[0056] Through the above technical solutions, this application effectively enhances the turbulence of the shell-side gas, increases the contact strength between the heat exchange tube bundle surface and the gas, and eliminates flow dead zones; by forcibly changing the gas flow direction, it extends the residence time of the gas in the heat exchange area and avoids fluid short-circuiting; and through an expandable baffle arrangement, it provides structural support for optimizing heat exchange efficiency under different operating conditions.

[0057] This application further proposes that the baffle be an arc-shaped baffle or a baffle rod.

[0058] Among them, the bow-shaped baffle refers to a plate-shaped structure with an arc-shaped profile, which can be implemented by a single bow or a double bow structure. It enhances the turbulence effect by guiding the gas to laterally scour the surface of the heat exchange tube bundle.

[0059] Among them, the flow deflector refers to the rod-shaped structure set along the flow direction. Specifically, it can be implemented using rods with circular or elliptical cross sections. By being arranged longitudinally in the shell-side flow channel, it generates vortices to disrupt the laminar boundary layer.

[0060] Specifically, the arc-shaped profile of the bow-shaped baffle creates alternating transverse flow paths for the shell-side gas, forcing it to repeatedly change direction and scour the surface of the heat exchange tube bundle, thereby increasing the contact area and residence time between the gas and the heat exchange tube bundle. The baffle rods, through their longitudinal distribution within the flow channel, generate longitudinal vortices as the gas flows around the rods, thus reducing the laminar boundary layer thickness and enhancing heat transfer. These two structures can be selected based on gas flow rate and pressure drop requirements: the bow-shaped baffle is suitable for conditions requiring higher turbulence intensity, while the baffle rods maintain a lower pressure drop while still improving heat transfer efficiency. By alternating or combining these structures, localized uneven heat transfer caused by a single flow direction can be avoided, while also preventing heat accumulation problems due to excessively low flow velocities.

[0061] Compared to existing technologies, traditional flat baffles are prone to creating flow dead zones due to structural limitations, leading to heat accumulation in localized areas of the heat exchange tube bundle. In contrast, the arc-shaped design of the bow-shaped baffle can evenly disperse airflow and eliminate dead zones. Compared to baffles that rely solely on lateral scouring, the longitudinal vortices generated by the baffle rods can cover a larger area of ​​the heat exchange surface, maintaining effective heat exchange even under low flow rate conditions.

[0062] Through the above technical solution, this application solves the problem of reduced local heat exchange efficiency and shortened equipment life caused by the single gas flow direction. By optimizing the baffle structure to enhance the turbulence effect, the shell-side gas distribution is made more uniform, which improves the overall heat exchange efficiency while reducing the risk of local overheating and adapting to the pressure drop and heat exchange requirements under different operating conditions.

[0063] This application further proposes that the heating gas outlet be located on the side wall of the pressure-bearing shell at a position corresponding to the upper cavity area.

[0064] The upper cavity region refers to the space above the upper tube sheet in the shell-side cavity, specifically formed by the gap between the support cylinder and the upper tube sheet to create a gas flow channel. This region serves as a collection area for the high-temperature gas after heat exchange, and its location is directly connected to the gap at the top of the support cylinder, ensuring that the gas naturally flows upward to the outlet after heat exchange is completed.

[0065] Specifically, as the high-temperature gas in the shell side, having completed heat exchange within the support cylinder, flows upward, it enters the upper cavity region through the gap between the support cylinder and the upper tube sheet. Since the outlet is located on the side wall corresponding to the upper cavity region, the gas can be discharged directly without changing its flow direction. This arrangement avoids the flow resistance caused by the gas needing to turn or revert within the cavity in traditional structures, while also shortening the residence time of the high-temperature gas in the shell side. The optimized gas flow path allows for rapid heat removal, effectively preventing localized temperature increases at the top of the cavity due to gas stagnation. The horizontal alignment design of the side wall outlet also utilizes the physical property of gas thermal expansion and upward movement, forming a unidirectional flow from bottom to top, reducing energy loss and alleviating thermal stress on the shell wall by lowering the flow velocity.

[0066] Compared to existing technologies, traditional gas-to-gas heat exchangers often place the heating gas outlet at the top or middle of the shell, causing the high-temperature gas to have to travel a long distance or change direction before it can be discharged. This design not only increases flow resistance but also creates high-temperature stagnation zones in the corners of the cavity. This solution, through the outlet arrangement on the sidewall corresponding to the upper cavity area, allows the gas to be discharged directly along the shortest path after heat exchange, eliminating the flow dead zones in traditional structures. Compared to the arrangement where the gas needs to overcome gravity to rise from the top outlet, this design better conforms to the natural upward flow pattern of high-temperature gas, significantly reducing the kinetic energy consumption required for gas discharge.

[0067] Through the above technical solution, this application effectively solves the problem of localized heat accumulation caused by an unreasonable exhaust path for high-temperature gas in the shell side. The optimized arrangement of the outlet position and the upper cavity region improves the gas flow direction, enabling the high-temperature gas after heat exchange to be quickly discharged from the equipment, avoiding heat retention caused by excessively long flow paths in traditional structures. Simultaneously, this design reduces flow resistance by matching the natural gas flow direction, thereby reducing energy loss during equipment operation and effectively mitigating the thermal stress concentration phenomenon on the shell wall caused by high-temperature gas scouring.

[0068] like Figure 4 As shown, this application further proposes an annular baffle including bolts, a pressure strip, a retaining ring, and a sealing strip. The pressure strip and the retaining ring are fastened together by bolts, and the sealing strip is disposed between the pressure strip and the pressure-bearing housing.

[0069] Bolts are fasteners used to connect the pressure bar and the retaining ring. Standard threaded fasteners can be used to achieve this. By tightening the bolts, an axial preload is generated, which makes the pressure bar and the retaining ring form a rigid connection structure.

[0070] Among them, the pressure strip refers to a metal component with a strip-shaped cross section, which can be made by cutting flat steel or angle steel. Its function is to cooperate with the retaining ring to clamp the sealing strip and to evenly transfer the clamping force applied by the bolt to the sealing strip.

[0071] The retaining ring refers to a ring-shaped support component, which can be formed by rolling and welding steel plates. Its inner diameter matches the outer diameter of the support cylinder, and an annular gap is formed between the outer diameter and the inner wall of the pressure-bearing shell. This gap is used to define the installation position of the sealing strip and provide support.

[0072] Among them, the sealing strip refers to a sealing component formed by stacking multiple layers of thin steel plates. Specifically, it can be made of stainless steel plates with a thickness of 0.1mm, with the number of layers controlled between 10 and 30. The elastic deformation of the multiple thin plates compensates for the size deviation of the annular gap, forming a flexible sealing interface.

[0073] Specifically, after the bolts pass through the mounting holes of the pressure strip and the retaining ring, the nuts are screwed in. By adjusting the tightness of the bolts, the pressure strip and the retaining ring form a rigid frame structure. The sealing strip is clamped between the pressure strip and the inner wall of the pressure-bearing shell, and under the action of the bolt preload, it undergoes radial compression deformation, filling the annular space between the pressure-bearing shell and the support cylinder. When the shell-side fluid enters the annular space from the cryogenic gas inlet, the continuous barrier layer formed by the sealing strip forces the fluid to be evenly distributed circumferentially along the annular space, preventing it from flowing directly to the heating gas outlet. Instead, it needs to enter the support cylinder from the bottom to exchange heat with the tube-side fluid.

[0074] Through the above technical solution, this application effectively solves the problem of shell-side fluid directly short-circuiting without heat exchange, ensuring that the cryogenic gas must flow through the heat exchange area to complete heat exchange, thus significantly improving heat exchange efficiency. The flexible multi-layer structure of the sealing strip can adapt to thermal expansion and deformation during equipment operation, avoiding seal failure caused by rigid contact, while simplifying the maintenance process of the sealing structure.

[0075] This application further proposes that the sealing strip is composed of a thin steel plate with a thickness of 0.1 mm, and has 10 to 30 layers.

[0076] Specifically, multiple layers of thin steel plates are stacked to form an elastic sealing strip. During bolt tightening, this strip undergoes uniform compression deformation, filling the assembly gap between the annular baffle and the pressure-bearing shell. When thermal expansion occurs during equipment operation, slight sliding occurs between the thin steel plate layers, consuming deformation stress through interlayer friction and preventing the sealing structure from cracking due to excessive rigidity. The lower limit of the number of layers ensures that the sealing strip can maintain sufficient contact pressure at high temperatures, while the upper limit prevents the sealing strip from losing its ability to compensate for thermal displacement due to an increase in overall rigidity caused by too many layers.

[0077] like Figure 5 As shown, this application further proposes a technical solution of setting guide distribution blades on the inner wall of the upper cavity region of the shell side.

[0078] The flow distribution blades are plate-like structures installed on the wall of the upper cavity region of the shell side. They can be implemented by welding or bolting, and their angle range can be controlled, for example, between 30° and 60°. The number of flow distribution blades can be set to, for example, 4 to 8, evenly distributed circumferentially, eliminating flow stagnation areas by changing the gas flow direction. These blades, by forming a flow-guiding surface at a specific angle, induce controlled turbulent motion of the shell-side gas.

[0079] Specifically, when the shell-side gas enters the upper cavity region, the guide vanes forcefully guide the gas flow path. The inclined surface of the vanes forces the gas to swirl, reducing the annular low-velocity zone formed at the top of the cavity. By adjusting the vane angle, the gas can achieve a uniform flow distribution before flowing through the heat exchange tube bundle. This structure eliminates flow dead zones while maintaining the original shell-side spatial layout, avoiding temperature accumulation caused by excessively low local flow velocities.

[0080] This application further proposes that the end cap be a conical end cap or an elliptical end cap. Conical end caps consume less material and have lower manufacturing costs, such as... Figure 6 As shown, the elliptical head has a larger volume, making it easier to manufacture and maintain.

[0081] Through the above technical solution, this application effectively eliminates the local overheating phenomenon in the upper shell-side cavity region, improving the uniformity of shell-side wall temperature distribution. Optimization of gas flow enhances the convective heat transfer efficiency between the shell and tube sides, while avoiding material thermal stress damage caused by excessive temperature gradients. This structure extends the continuous operating cycle under high-temperature conditions while maintaining equipment compactness.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Images