Linear quench heat exchanger

Abstract

The present disclosure relates to a linear quench heat exchanger, comprising: a tube body, the tube body comprising an inner tube and an outer tube, the outer tube being sleeved on the inner tube and forming an annular chamber between the inner tube and the outer tube; a connecting piece, the connecting piece comprising an inner cylinder and an outer cylinder, the inner cylinder and the outer cylinder being coaxially arranged and connected, a communication space being formed between the inner cylinder and the outer cylinder, the outer cylinder being provided with a water inlet; a water inlet pipe, the water inlet pipe being tangentially connected to the outer cylinder, and the water inlet pipe being communicated with the communication space and the annular chamber through the water inlet; and a baffle, the baffle being configured as an arc-shaped plate and having a first end and a second end, the first end being connected to the outer cylinder, and an included angle between a line connecting the first end and a center axis of the tube body and a line between the water inlet and the center axis of the tube body being 90°-120°, the second end being spaced from the outer cylinder and the inner cylinder, the linear quench heat exchanger having good anti-fouling capacity.

Description

Technical Field

[0001] This disclosure relates to the field of shell-and-tube heat exchanger technology, and more specifically, to a linear quench heat exchanger. Background Technology

[0002] Linear quench heat exchangers mainly consist of an inner tube and an outer tube forming a shell-and-tube structure. Upper and lower connectors are installed at both ends of the inner and outer tubes to connect them. Impurities or scale easily accumulate inside the outer tube, often leading to scaling problems, especially at the bottom of the outer tube and on the surface of the lower connector. Because the metal temperature of the inner tube is very high, when scale accumulates on the outer surface of the inner tube, it will block heat exchange, causing the wall temperature of the inner tube to rise sharply, and even burn through the inner tube.

[0003] In related technologies, boiler feedwater enters the shell-side annulus tangentially from the lower header connection, forming a spiral flow at the bottom of the shell side. This intensifies water turbulence, which helps flush out deposited scale. However, the fluid rotating along the outer wall of the inner tube exhibits a wake effect. That is, the tangentially entering fluid rotates 90°, passing through a quarter of the circumference (one quadrant), and due to the low velocity of the medium in the wake zone, scale easily forms on the outer surface of the inner tube. In engineering practice, scaling and metal wall burn-through are frequently observed here, affecting heat exchange. Summary of the Invention

[0004] The purpose of this disclosure is to provide a linear quench heat exchanger with good anti-fouling ability.

[0005] To achieve the above objectives, this disclosure provides a linear quench heat exchanger, comprising: a tube body including an inner tube and an outer tube, the outer tube being sleeved on the inner tube and forming an annular chamber between them; a connector including an inner cylinder and an outer cylinder, the inner cylinder and the outer cylinder being coaxially arranged and connected, a communicating space being formed between the inner cylinder and the outer cylinder, and the outer cylinder being provided with a water inlet; a water inlet pipe tangentially connected to the outer cylinder, and the water inlet pipe communicating with the communicating space and the annular chamber through the water inlet; and a baffle, the baffle being constructed as an arc-shaped plate having a first end and a second end, the first end being connected to the outer cylinder, and the angle between the line connecting the first end and the central axis of the tube body and the line connecting the water inlet and the central axis of the tube body being 90°~120°, and the second end being spaced apart from the outer cylinder and the inner cylinder.

[0006] Optionally, a first included angle α is formed between the line connecting the first end of the baffle to the central axis of the tube and the line connecting the second end of the baffle to the central axis of the tube, wherein the first included angle α is 45°~90°.

[0007] Optionally, the baffle is provided with a plurality of drain holes at intervals, the drain holes being used to allow fluid to pass through.

[0008] Optionally, the plane in which the baffle is located is perpendicular to the plane in which the cross-section of the tube is located.

[0009] Optionally, the connector has a tangential side and an opposite side, the tangential side is connected to a water inlet pipe, the opposite side is located opposite the tangential side, the line connecting the lowest point of the tangential side and the lowest point of the opposite side has a second included angle β with the cross section of the pipe body, the second included angle β is less than 10°, and the lowest point of the tangential side is lower than the lowest point of the opposite side.

[0010] Optionally, the linear quench heat exchanger further includes a spacer connected between the second end of the baffle and the outer cylinder, wherein the length of the spacer is in the ratio of 1 / 4 to 1 / 2 of the width of the annular chamber.

[0011] Optionally, the linear quench heat exchanger further includes a spiral spacer plate, which is spirally wound around the outer wall of the inner tube along the extension direction of the tube body, and the width of the spiral spacer plate matches the width of the annular chamber.

[0012] Optionally, the spiral spacer plate has a plurality of air holes spaced apart, and the plurality of air holes are arranged along the extension direction of the spiral spacer plate.

[0013] Optionally, the spiral spacer plate includes multiple spacer plates, which are arranged along the extension direction of the spiral spacer plate. The spacer plates are connected to the outer wall of the inner tube, and two adjacent spacer plates form annular holes with the outer wall of the inner tube.

[0014] Optionally, each of the spiral spacers forms an annular hole of varying width with the outer wall of the inner tube. The width of the annular hole formed by the spiral spacers and the outer wall of the inner tube away from the water inlet is greater than the width of the annular hole formed by the spiral spacers and the outer wall of the inner tube closer to the water inlet.

[0015] Through the above technical solution, the medium enters the pipe body through the inlet and flows in the annular chamber to cool the pyrolysis gas entering the internal space of the pipe body. Specifically, the medium enters the communicating space through the inlet pipe. Since the inlet pipe is tangentially connected to the outer cylinder, the medium entering tangentially will have a reduced flow velocity when rotating approximately 1 / 4 of a circumference (90°), forming a wake zone. The fluid in the wake zone will wash over the outer cylinder due to centrifugal force, but the flow velocity near the inner cylinder will decrease, making it easier for scale to form on the inner pipe wall. By connecting a baffle to the outer cylinder, the angle between the line connecting the first end of the baffle to the central axis of the pipe body and the line connecting the inlet to the central axis of the pipe body is 90°~120°. The baffle plate, positioned at °, covers the wake zone. Its second end is spaced from the inner wall of the outer cylinder. Thus, when the fluid rotating along the outer wall of the inner cylinder completes a quarter turn, the baffle plate locally compresses the space of the rotating fluid, thinning the wake zone opposite the inlet. This increases the velocity of the medium in this area, strengthens fluid turbulence, and allows the medium to form a stable spiral flow between the inner and outer pipes. This prevents scale buildup in the wake zone opposite the inlet and avoids the deposition of heavier substances like scale due to reduced flow velocity when the medium enters the pipe. Furthermore, it prevents scale accumulation on the outer surface of the inner pipe, which can hinder heat exchange and cause a rapid increase in the temperature of the inner pipe wall, potentially burning through it.

[0016] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic cross-sectional view of the overall structure of the quench heat exchanger provided in this embodiment of the disclosure; Figure 2 yes Figure 1 Cross-sectional view at point AA; Figure 3 This is a schematic diagram of the spiral spacer plate structure of the quench heat exchanger provided in this embodiment, showing the annular holes and air holes.

[0018] Explanation of reference numerals in the attached figures 1-Pipe body, 11-Inner pipe, 12-Outer pipe, 2-Connector, 21-Inner cylinder, 22-Outer cylinder, 23-Inlet, 3-Inlet pipe, 4-Baffle, 41-Drain hole, 5-Spacing component, 6-Spiral spacing plate, 61-Air hole, 62-Spacing support plate, 63-Annular hole, 10-Cracked gas inlet pipe, 20-Cracked gas header, 30-Cracked gas outlet pipe, 40-Water supply inlet pipe, 50-Lower header, 60-Upper header, 70-Water vapor outlet pipe. Detailed Implementation

[0019] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0020] In this disclosure, unless otherwise stated, the directional terms "inner" and "outer" refer to "inner" and "outer" relative to the contour of the corresponding component itself. The directional terms "upper" and "lower" generally refer to "upper" and "lower" relative to each other in the direction of gravity when the corresponding component is in use. Furthermore, the use of terms such as "first" and "second" is for distinguishing different components and does not indicate sequence or importance. In addition, in the following description, when referring to the accompanying drawings, the same reference numerals in different drawings denote the same elements. Those skilled in the art should understand that the above definitions are for explanation and illustration only and should not be construed as limiting the present disclosure.

[0021] According to a specific embodiment of this disclosure, refer to Figures 1 to 3 As shown, a linear quench heat exchanger is provided. The linear quench heat exchanger includes: a tube body 1, which includes an inner tube 11 and an outer tube 12. The outer tube 12 is sleeved on the inner tube 11 and forms an annular chamber between the outer tube 11 and the inner tube 11; and a connector 2, which includes an inner cylinder 21 and an outer cylinder 22. The inner cylinder 21 and the outer cylinder 22 are arranged coaxially and connected. A communication space is formed between the inner cylinder 21 and the outer cylinder 22. The outer cylinder 22 is provided with a water inlet 23. Water inlet pipe 3 is tangentially connected to outer cylinder 22 and connects the connecting space and annular chamber through water inlet 23; and baffle 4 is constructed as an arc plate with a first end and a second end. The first end is connected to outer cylinder 22 and the angle between the line connecting the first end to the central axis of pipe 1 and the line connecting the water inlet 23 to the central axis of pipe 1 is 90°~120°. The second end is spaced apart from outer cylinder 22 and inner cylinder 21.

[0022] Through the above technical solution, the medium enters the pipe body 1 through the inlet 23 and flows in the annular chamber to cool the pyrolysis gas entering the internal space of the pipe body 1. The medium enters the communicating space through the inlet pipe 3. Since the inlet pipe 3 is tangentially connected to the outer cylinder 22, the medium entering tangentially will have a reduced flow velocity when rotating approximately 1 / 4 of a circumference (90°), forming a wake zone. The fluid in the wake zone will wash over the outer cylinder 22 due to centrifugal force. However, the flow velocity near the inner cylinder 21 will decrease, making it easier for scale to form on the wall of the inner pipe 11. A baffle 4 is connected to the outer cylinder 22, and the angle between the line connecting the first end of the baffle 4 to the central axis of the pipe body 1 and the line connecting the inlet 23 to the central axis of the pipe body 1 is set to 90°. The baffle 4 is angled at 120° to cover the wake region. The second end is spaced from the inner wall of the outer cylinder 22. Thus, when the fluid rotating along the outer wall of the inner cylinder 21 completes a quarter turn, the baffle 4 can locally compress the space of the rotating fluid, thinning the wake region opposite the inlet 23. This increases the flow velocity of the medium in this region, strengthens fluid turbulence, and allows the medium to form a stable spiral flow between the inner pipe 11 and the outer pipe 12. This prevents scaling in the wake region opposite the inlet 23 and avoids the deposition of heavier substances, such as scale, due to the reduced flow velocity when the medium enters the pipe body 1. Furthermore, it prevents scale from accumulating on the outer surface of the inner pipe 11, thus preventing heat exchange and avoiding a rapid increase in the temperature of the inner pipe 11 wall, which could lead to burn-through of the inner pipe 11.

[0023] Among them, reference Figure 1 and Figure 2 As shown, high-temperature pyrolysis gas enters directly from bottom to top into the pyrolysis gas inlet pipe 10, then enters the inner pipe 11 through the internal space enclosed by the lower connector 2. After being cooled by water in the annular chamber, it enters the pyrolysis gas header 20 at the top and flows out through the pyrolysis gas outlet pipe 30. The medium, namely boiler feedwater, enters the lower header 50 through the feedwater inlet pipe 40. After distribution, it enters the communicating space of the lower connector 2 through the water inlet pipe 3, and then enters the annular chamber from bottom to top. The boiler feedwater is heated by the high-temperature pyrolysis gas until it boils. The mixed fluid with steam enters the upper header 60 for collection, and then flows out through the steam outlet pipe 70.

[0024] In some embodiments of this disclosure, reference is made to Figure 2 As shown, a first included angle α is formed between the line connecting the first end of the baffle 4 to the central axis of the pipe body 1 and the line connecting the second end of the baffle 4 to the central axis of the pipe body 1, wherein the first included angle α is 45°~90°. In this way, on the one hand, the length of the baffle 4 can ensure that when the medium rotates in and forms a wake zone, the baffle 4 can cut thin the fluid space, strengthen the fluid disturbance in time, and accelerate the medium flow rate. On the other hand, it avoids the baffle 4 being set too long, which would increase the resistance of the fluid medium and affect the fluid rate of the medium.

[0025] In some embodiments of this disclosure, reference is made to Figure 2 As shown, multiple drain holes 41 can be provided on the baffle 4 at intervals, and the drain holes 41 are used for fluid to pass through. In this way, the medium flowing through the baffle 4 can enter between the baffle 4 and the outer cylinder 22 through the drain holes 41 to create disturbance, thereby preventing the formation of solid deposits between the baffle 4 and the outer cylinder 22.

[0026] In some embodiments of this disclosure, reference is made to Figure 2 As shown, the plane where the baffle 4 is located is perpendicular to the plane of the cross-section of the pipe body 1. In this way, the baffle 4 can be vertically arranged between the inner cylinder 21 and the outer cylinder 22, avoiding the impact on the capacity and flow velocity of the medium passing through the baffle 4 when the end of the baffle 4 away from the bottom of the connector 2 is inclined towards the inner cylinder 21. Furthermore, it avoids the weakening effect of the baffle 4 on the medium in the wake zone and the reduction of the squeezing effect on the fluid when the end of the baffle 4 away from the bottom wall of the connector 2 is inclined towards the outer cylinder 22.

[0027] In some embodiments of this disclosure, reference is made to Figure 1 As shown, connector 2 has a tangential side and an opposite side. The tangential side is connected to the inlet pipe 3, and the opposite side is located opposite the tangential side. The line connecting the lowest point of the tangential side and the lowest point of the opposite side forms a second angle β with the cross-section of the pipe body 1. The second angle β is less than 10°, and the lowest point of the tangential side is lower than the lowest point of the opposite side. Since scale tends to accumulate at low points, by setting the height of the tangential side to be lower than the height of the opposite side, it is not easy for impurities to accumulate on the opposite side. Furthermore, since the inlet 23 is a low point, it is also not easy for scale to accumulate due to the impact of the incoming medium. Thus, scale accumulation is further prevented.

[0028] In some embodiments of this disclosure, reference is made to Figure 2 As shown, the linear ultracooling heat exchanger may further include a spacer 5 connected between the second end of the baffle 4 and the outer cylinder 22. The length of the spacer 5 is 1 / 4 to 1 / 2 of the width of the annular chamber. This spacer 5 maintains the distance between the second end of the baffle 4 and the outer cylinder 22, thus positioning the baffle 4 and preventing it from shifting under fluid impact. This allows the baffle 4 to effectively thin the wake region and compress the fluid space. When the distance between the second end and the outer cylinder 22 is less than 1 / 4, the baffle 4's compression effect on the fluid is weak, and scale is easily deposited. When the distance is greater than 1 / 2, the baffle 4 occupies a larger space, increasing resistance to the fluid and hindering fluid flow.

[0029] In some embodiments of this disclosure, reference is made to Figure 1As shown, the linear quench heat exchanger may further include a spiral spacer plate 6, which is spirally wound around the outer wall of the inner tube 11 along the extension direction of the tube body 1. The width of the spiral spacer plate 6 matches the width of the annular chamber. This serves two purposes: firstly, the spiral spacer plate 6 maintains the distance between the inner tube 11 and the outer tube 12, preventing inconsistent gaps between them due to excessive tube body 1 length; secondly, the spiral spacer plate 6 guides the flow of the medium, allowing the upward-flowing medium in the annular chamber to flow along the spiral spacer plate 6 and form a stable spiral flow, thereby enhancing heat transfer. Furthermore, the spiral flow of the fluid medium can carry away scale, further improving the quench heat exchanger's anti-fouling capability.

[0030] In some embodiments of this disclosure, reference is made to Figure 1 and Figure 3 As shown, a plurality of vents 61 are spaced apart on the spiral spacer plate 6, and the plurality of vents 61 are arranged along the extending direction of the spiral spacer plate 6. Since the medium will be heated and vaporized, the generated bubbles will rise. By opening a plurality of vents 61 on the spiral spacer plate 6, the bubbles can rise through the vents 61 and through the spiral spacer plate 6, avoiding the bubbles from adsorbing and remaining on the spiral spacer plate 6 and causing cavitation.

[0031] In some embodiments of this disclosure, reference is made to Figure 3 As shown, the spiral spacer plate 6 may include multiple spacer support plates 62, which are arranged along the extending direction of the spiral spacer plate 6. The spacer support plates 62 are connected to the outer wall of the inner tube 11, and two adjacent spacer support plates 62 form annular holes 63 with the outer wall of the inner tube 11. In this way, when the medium in the annular chamber vaporizes more violently, the bubbles are generated and rise at a faster rate. Since the annular holes 63 have a large gap, the obstruction to the bubbles can be reduced, allowing a large number of bubbles to pass through quickly.

[0032] The spiral spacer plate 6 can be assembled from multiple plates to be joined to the outside of the inner tube 11. Adjacent spiral spacer plates 6 are staggered to form gaps, allowing for medium flow and facilitating the passage of air bubbles. In some embodiments, the plates can be assembled from multiple spiral spacer plates 6 with vent holes 61. In other embodiments, the plates can be assembled from spiral spacer plates 6 with annular holes 63. Alternatively, depending on the required height of the tube body 1, plates with vent holes 61 can be joined at the lower part of the tube body 1, and plates with annular holes 63 can be joined at the upper part of the tube body 1. This disclosure does not impose specific limitations in this regard.

[0033] In some embodiments of this disclosure, reference is made to Figure 3As shown, each spiral spacer plate 6 and the outer wall of the inner tube 11 can form annular holes 63 of varying widths. The width of the annular holes 63 formed by the spiral spacer plate 6 and the outer wall of the inner tube 11 away from the inlet 23 is greater than that of the annular holes 63 formed by the spiral spacer plate 6 and the outer wall of the inner tube 11 closer to the inlet 23. Since the medium flows upward in the tube 1, and during the flow, most of the medium in the upper part can be converted into steam, by setting the width of the annular holes 63 away from the inlet 23 to be greater than the width of the annular holes 63 closer to the inlet 23, it is possible to accommodate the situation where there are more steam bubbles in the upper part of the annular chamber, so that a large number of bubbles can pass through the annular holes 63.

[0034] Below, for reference Figures 1 to 3 As shown, this disclosure will provide a detailed description of the specific usage process of the linear quench heat exchanger in conjunction with the above-described specific embodiments. When using the linear quench heat exchanger of this disclosure to cool high-temperature pyrolysis gas, the high-temperature pyrolysis gas directly enters the pyrolysis gas inlet pipe 10 from bottom to top, and then enters the interior of the inner tube 11 through the internal space enclosed by the lower connector 2. At the same time, boiler feedwater enters the lower header 50 through the feedwater inlet pipe 40, and after distribution, enters the communicating space of the lower connector 2 through the water inlet pipe 3. Since the water inlet pipe 3 is tangentially connected to the outer cylinder 22, and a baffle 4 is connected to the outer cylinder 22, the fluid medium rotating along the outer wall of the inner cylinder 21 is circulated around... After a quarter of a cycle, the baffle 4 can locally squeeze the space of the rotating fluid to cut thin the wake zone opposite the inlet 23, thereby increasing the medium velocity in this area and strengthening the turbulence of the fluid medium. This allows the medium to form a stable spiral flow between the inner pipe 11 and the outer pipe 12, so that the boiler feedwater can enter the annular chamber from bottom to top along the spiral spacer plate 6. The cracked gas will be cooled by the water in the annular chamber and enter the cracked gas header 20 at the top, and then flow out through the cracked gas outlet pipe 30. The boiler feedwater will also be heated by the high temperature cracked gas until it boils. The mixed fluid with steam enters the upper header 60 for collection and then flows out through the steam outlet pipe 70.

[0035] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0036] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0037] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A linear quench heat exchanger, characterized in that, The linear quench heat exchanger includes: The tube body includes an inner tube and an outer tube, the outer tube being sleeved on the inner tube and forming an annular cavity between them; A connector, comprising an inner cylinder and an outer cylinder, wherein the inner cylinder and the outer cylinder are arranged coaxially and connected, a communicating space is formed between the inner cylinder and the outer cylinder, and the outer cylinder is provided with a water inlet; A water inlet pipe, tangentially connected to the outer cylinder, and the water inlet pipe connecting the communicating space and the annular chamber via the water inlet; and The baffle is constructed as an arc-shaped plate and has a first end and a second end. The first end is connected to the outer cylinder, and the angle between the line connecting the first end and the central axis of the pipe body and the line connecting the water inlet and the central axis of the pipe body is 90°~120°. The second end is spaced apart from the outer cylinder and the inner cylinder.

2. The linear quench heat exchanger according to claim 1, characterized in that, A first included angle α is formed between the line connecting the first end of the baffle to the central axis of the tube and the line connecting the second end of the baffle to the central axis of the tube, wherein the first included angle α is 45°~90°.

3. The linear quench heat exchanger according to claim 1, characterized in that, The baffle is provided with a plurality of drain holes at intervals, which are used for the passage of fluid.

4. The linear quench heat exchanger according to claim 1, characterized in that, The plane in which the baffle is located is perpendicular to the plane in which the cross-section of the tube is located.

5. The linear quench heat exchanger according to claim 1, characterized in that, The connector has a tangential side and an opposite side. The tangential side is connected to a water inlet pipe. The opposite side is located opposite the tangential side. The line connecting the lowest point of the tangential side and the lowest point of the opposite side has a second included angle β with the cross-section of the pipe body. The second included angle β is less than 10°. The lowest point of the tangential side is lower than the lowest point of the opposite side.

6. The linear quench heat exchanger according to claim 1, characterized in that, The linear quench heat exchanger also includes a spacer connected between the second end of the baffle and the outer cylinder, wherein the length of the spacer is in the ratio of 1 / 4 to 1 / 2 of the width of the annular chamber.

7. The linear quench heat exchanger according to claim 1, characterized in that, The linear quench heat exchanger also includes a spiral spacer plate, which is spirally wound around the outer wall of the inner tube along the extension direction of the tube body, and the width of the spiral spacer plate matches the width of the annular chamber.

8. The linear quench heat exchanger according to claim 7, characterized in that, The spiral spacer plate has a plurality of air holes spaced apart, and the plurality of air holes are arranged along the extension direction of the spiral spacer plate.

9. The linear quench heat exchanger according to claim 7, characterized in that, The spiral spacer plate includes multiple spacer plates, which are arranged along the extension direction of the spiral spacer plate. The spacer plates are connected to the outer wall of the inner tube, and two adjacent spacer plates form annular holes with the outer wall of the inner tube.

10. The linear quench heat exchanger according to claim 9, characterized in that, Each of the spiral spacers forms an annular hole of varying width with the outer wall of the inner tube. The annular hole formed by the spiral spacers away from the inlet and the outer wall of the inner tube is wider than the annular hole formed by the spiral spacers closer to the inlet and the outer wall of the inner tube.

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