Heat exchanger, heat exchange system and method for cleaning heat exchange tube of heat exchanger

Abstract

The present application relates to chemical technology field, disclose a heat exchanger, heat exchange system and the method for removing scale of heat exchanger's heat exchange pipe, the heat exchanger includes heat exchange body, the pipe box with cavity and the diffusion mechanism being arranged in the cavity, the heat exchange body includes heat exchange shell and the heat exchange pipe being arranged in the heat exchange shell, both ends of the heat exchange pipe are formed respectively for the pipe import and pipe export of the heat exchange medium, which is used for the heat exchange medium, the heat exchange shell is provided with the shell import and shell export respectively for the heat exchange medium, which is used for the heat exchange medium, the pipe box is provided with the communication port being communicated with the pipe import respectively and the pipe box import for the heat exchange medium containing impact particle into the cavity, the heat exchange body is located outside the cavity, the diffusion mechanism is arranged to be able to make the impact particle in the heat exchange medium eject into the heat exchange pipe, so that, while heat exchanging, the dirt can be removed, so that the cleaning operation is not needed to stop the vehicle.

Description

Technical Field

[0001] This invention relates to the field of chemical technology, and more specifically to heat exchangers, heat exchange systems, and methods for descaling heat exchanger tubes. Background Technology

[0002] A heat exchanger is a device that transfers some of the heat from a hot fluid to a cold fluid; it is also called a heat exchanger. Heat exchangers are commonly used heat exchange equipment in chemical production. After prolonged operation, scale buildup will inevitably occur in heat exchangers.

[0003] Taking a shell-and-tube heat exchanger as an example, after a long period of operation, due to the heat exchange and evaporation of the fluid to be heat exchanged, scale will accumulate on the inner wall of the heat exchange tubes. Scale will reduce the heat transfer efficiency of the heat exchanger, so it is necessary to perform regular descaling operations on the heat exchanger.

[0004] Currently, the common practice is to clean and descale the vehicle after it has been parked. However, this not only affects work efficiency but also increases labor intensity. Summary of the Invention

[0005] The purpose of this invention is to overcome the problem of cleaning the dirt inside the heat exchange tubes during shutdown in the prior art. It provides a heat exchanger with a diffusion mechanism that allows impact particles in the heat exchange medium to be ejected into the heat exchange tube to remove the dirt deposited inside the heat exchange tube. In this way, dirt can be removed while heat exchange is being performed, thus eliminating the need for shutdown for cleaning.

[0006] To achieve the above objectives, the present invention provides a heat exchanger comprising:

[0007] The heat exchange body includes a heat exchange shell and a heat exchange tube disposed in the heat exchange shell. The two ends of the heat exchange tube are respectively formed as a tube inlet and a tube outlet for the heat exchange medium to be exchanged. The heat exchange shell is provided with a shell inlet and a shell outlet for the heat exchange medium to exchange heat with the heat exchange medium to be exchanged.

[0008] A tube box having a cavity, the tube box being provided with a communication port respectively connected to the tube inlet and a tube box inlet for the heat exchange medium containing impact particles to enter the cavity, the heat exchange body being located outside the cavity; and

[0009] A diffusion mechanism is disposed within the cavity and is configured to eject impact particles in the heat exchange medium into the heat exchange tube.

[0010] The above-described technical solution, by incorporating a diffusion mechanism within the cavity, allows impact particles in the heat exchange medium to be ejected into the heat exchange tube. This flushes away the scale deposited on the inner wall of the heat exchange tube, achieving descaling and inhibiting the formation of new scale. Furthermore, since descaling can be performed simultaneously with heat exchange operations, cleaning can be achieved without stopping the system, significantly improving operational efficiency.

[0011] Preferably, the diffusion mechanism includes:

[0012] A diffusion cylinder, disposed within the cavity, is provided with a diffusion inlet communicating with the inlet of the tube box and a diffusion outlet for discharging the impact particles; and

[0013] An impact plate is disposed inside the diffusion cylinder and is configured to eject the impact particles entering through the diffusion inlet from the diffusion outlet.

[0014] Preferably, the diffusion inlet is located at the end of the diffusion cylinder, the diffusion outlet is located on the side wall of the diffusion cylinder, and the diffusion outlet is oriented towards the communication port;

[0015] The impact plate is disposed above the diffusion outlet, and the impact plate has a material-facing surface that bulges toward the diffusion inlet so that the impact particles in the heat exchange medium are refracted and ejected from the diffusion outlet during their journey.

[0016] Preferably, the tube box has a first sidewall and a second sidewall that are opposite to each other, and two sets of communication ports are respectively disposed on the first sidewall and the second sidewall. Each set of communication ports includes at least one of the communication ports. The heat exchanger includes a pair of heat exchange bodies respectively disposed on the first sidewall and the second sidewall, wherein the heat exchange tube is installed in the communication port of the corresponding sidewall.

[0017] The sidewall of the diffusion cylinder is provided with a pair of diffusion outlets that are opposite each other, and the receiving surface enables the impact particles to be ejected from the corresponding diffusion outlet of the pair of diffusion outlets.

[0018] Preferably, the first sidewall is formed as an arcuate surface protruding outward from the cavity, and / or the second sidewall is formed as an arcuate surface protruding outward from the cavity.

[0019] Preferably, the sidewall of the diffusion cylinder is provided with multiple pairs of diffusion outlets arranged along the axial direction of the diffusion cylinder;

[0020] The diffusion mechanism includes a plurality of impact plates disposed inside the diffusion cylinder and corresponding to the respective diffusion outlets, and the impact plates are provided with gaps for the heat exchange medium to pass through.

[0021] Preferably, in adjacent impact plates, the gap between one impact plate and the gap between the other impact plate are staggered.

[0022] Preferably, the impact plate near the diffusion inlet is a first impact plate, and the gap of the first impact plate is located at the edge of the first impact plate; the impact plate adjacent to the first impact plate is a second impact plate, and the gap of the second impact plate is located at the middle and / or edge of the second impact plate.

[0023] Preferably, the diffusion outlet gradually widens in the direction from inside the diffusion cylinder to outside the diffusion cylinder.

[0024] Preferably, the heat exchanger includes a stirring mechanism disposed within the cavity, the stirring mechanism including a stirring paddle disposed between the diffusion outlet and the communication port, the stirring paddle being able to agitate the heat exchange medium to drive the impact particles into the communication port.

[0025] Preferably, the stirring paddle includes a stirring shaft and a stirring body disposed on the stirring shaft. The stirring body includes a plurality of stirring plates disposed along the axial direction of the stirring shaft. The stirring plates are symmetrically disposed about the stirring shaft, and the stirring shaft can drive the plurality of stirring plates to rotate around the axis of the stirring shaft.

[0026] Preferably, the stirring paddle includes a frame surrounding the outer periphery of the stirring body; and / or

[0027] The stirring body is formed into a first end and a second end at its two ends along the axial direction of the stirring shaft, and the stirring body is gradually expanded in the direction from the first end toward the middle of the stirring body, and the stirring body is gradually expanded in the direction from the second end toward the middle of the stirring body.

[0028] Preferably, the tube box is provided with a plurality of the communication ports, and the heat exchanger includes a plurality of heat exchange tubes respectively installed in the corresponding communication ports;

[0029] The heat exchanger includes a manifold, which has a manifold chamber and a manifold inlet connected to the pipe outlet.

[0030] A second aspect of the present invention provides a heat exchange system, the heat exchange system including a heat exchanger and a solid-liquid separator provided by the present invention, the solid-liquid separator being provided with a separation inlet connected to the tube outlet, the solid-liquid separator being capable of performing solid-liquid separation on the medium discharged from the heat exchange tube, and the solid-liquid separator being provided with a solid outlet for discharging the separated impact particles and a liquid outlet for discharging the separated heat exchange medium.

[0031] The solid discharge outlet is connected to the diffusion inlet.

[0032] Preferably, the heat exchange system includes a particle receiving tank, which is provided with a particle inlet and a particle outlet for impact particles to enter and exit, respectively. The particle inlet is connected to the solid discharge outlet, and the particle outlet is connected to the diffusion inlet; and / or

[0033] The heat exchange system includes a liquid receiving tank, which has a receiving chamber capable of containing the heat exchange medium. The liquid receiving tank is provided with a drain port for discharging the heat exchange medium from the receiving chamber, and the drain port is connected to the diffusion inlet.

[0034] A third aspect of the present invention provides a method for descaling heat exchanger tubes, the method comprising the following steps:

[0035] A heat exchange medium containing impact particles is introduced into the heat exchange tubes of the heat exchanger to flush away the dirt on the inner wall of the heat exchange tubes.

[0036] Preferably, the material of the impact particles is selected from at least one of engineering plastics, alumina, stainless steel, and zirconium silicate; and / or

[0037] The solid content of the impact particles is 3%-8%. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of a heat exchange system according to a preferred embodiment of the present invention, wherein a heat exchanger according to a preferred embodiment of the present invention is provided.

[0039] Figure 2 yes Figure 1 The diagram shows a partial structural schematic of the tube box of the heat exchanger in the heat exchange system, including a side view of the structure having a first side wall or a second side wall.

[0040] Figure 3 yes Figure 1 A schematic cross-sectional view of the diffusion mechanism in the heat exchanger of the heat exchange system shown.

[0041] Figure 4 yes Figure 3A side view of the diffusion mechanism shown.

[0042] Figure 5 yes Figure 3 A top view of the diffusion mechanism shown.

[0043] Figure 6 yes Figure 1 The diagram shows the main structural view of the stirring mechanism in the heat exchanger of the heat exchange system.

[0044] Explanation of reference numerals in the attached figures

[0045] 10-Heat exchanger; 12-Heat exchange body; 120-Heat exchange shell; 122-Heat exchange tube; 14-Pipe box; 14a-First sidewall; 14b-Second sidewall; 140-Cavity; 16-Diffusion mechanism; 160-Diffusion cylinder; 160a-Diffusion outlet; 162-Impact plate; 162a-First impact plate; 162b-Second impact plate; 162c-Third impact plate; 164-Gap; 18-Stirring mechanism; 180-Stirring paddle; 180a-Stirring shaft; 180b-Stirring plate; 180c-Frame; 19-Manifold box; 20-Heat exchange system; 22-Solid-liquid separator; 24-Particle collection tank; 26-Liquid receiving tank; 27a-Transfer pump; 27b-Transfer pipe; 28-Three-way valve. Detailed Implementation

[0046] In this invention, unless otherwise stated, directional terms such as "up," "down," "left," and "right" are generally understood in conjunction with the accompanying drawings and the orientation shown in actual application, while "inner" and "outer" refer to the inner and outer contours of the component.

[0047] This invention provides a heat exchanger, such as Figure 1 As shown, the heat exchanger 10 includes a heat exchange body 12, a tube box 14, and a diffusion mechanism 16.

[0048] The heat exchanger body 12 includes a heat exchange shell 120 and heat exchange tubes 122 disposed within the heat exchange shell 120. The two ends of the heat exchange tubes 122 are respectively formed as a tube inlet and a tube outlet. The tube inlet allows the heat exchange medium to enter, and the tube outlet allows the heat exchange medium to exit. The heat exchange shell 120 is provided with a shell inlet and a shell outlet. The shell inlet allows the heat exchange medium to enter and exchange heat with the heat exchange medium to exit, and the shell outlet allows the heat exchange medium to exit. Multiple heat exchange tubes 122 can be disposed within the heat exchange shell 120, and the multiple heat exchange tubes 122 can be evenly distributed within the heat exchange shell 120.

[0049] The tube box 14 has a cavity 140, and is provided with a connecting port and a tube box inlet. The connecting port is connected to the tube inlet. It is understood that the heat exchange tube 122 can be installed at the connecting port. The tube box inlet allows the heat exchange medium containing impact particles to enter the cavity 140. After entering the cavity 140 along with the heat exchange medium, the impact particles enter the heat exchange tube 122 through the connecting port, and can flush away the dirt deposited on the inner wall of the heat exchange tube 122. Furthermore, the heat exchange cup 12 is located outside the cavity 140. The material of the impact particles can be selected from at least one of engineering plastics, alumina, stainless steel, and zirconium silicate. Specifically, the engineering plastic can be at least one of polyamide, polycarbonate, polyoxymethylene, polyimide, and polysulfone. When multiple heat exchange tubes 122 are provided, multiple communication ports corresponding to the respective heat exchange tubes 122 can be provided on the tube box 14. That is, the tube box 14 can be provided with multiple communication ports, and the heat exchanger 10 can include multiple heat exchange tubes 122 respectively installed in the corresponding communication ports. It is understood that the heat exchange body 12 can be located outside the cavity 140. In order to improve the heat exchange effect, the multiple communication ports can be evenly distributed on the wall of the tube box 14.

[0050] The diffusion mechanism 16 is disposed in the cavity 140 and is configured to allow impact particles in the heat exchange medium to be ejected into the heat exchange tube 122.

[0051] By providing a diffusion mechanism 16 within the cavity 140, impact particles in the heat exchange medium can be ejected into the heat exchange tube 122, thereby flushing away the scale deposited on the inner wall of the heat exchange tube 122 and achieving descaling, while also inhibiting the formation of new scale. Furthermore, since descaling can be performed during heat exchange operations, cleaning can be achieved without stopping the system, greatly improving operational efficiency.

[0052] Combination Figure 1 and Figure 3 As shown, the diffusion mechanism 16 may include a diffusion cylinder 160, which may be disposed within the cavity 140. The diffusion cylinder 160 may be provided with a diffusion inlet communicating with the inlet of the tube box and a diffusion outlet 160a for discharging impact particles. It is understood that the impact particles may be discharged from the diffusion outlet 160a along with the heat exchange medium. The diffusion mechanism 16 also includes an impact plate 162, which may be disposed within the diffusion cylinder 160. The impact plate 162 may be configured to eject impact particles entering through the diffusion inlet from the diffusion outlet 160a. The diffusion inlet may be located at the end of the diffusion cylinder 160, such as... Figure 1 As shown in the diagram, the diffusion inlet can be located at the bottom end of the diffusion cylinder 160, combined with... Figure 1 and Figure 4As shown, the diffusion outlet 160a can be disposed on the side wall of the diffusion cylinder 160, and the diffusion outlet 160a can be oriented towards the communication port. When the heat exchange medium containing impact particles enters the diffusion cylinder 160 from the bottom end of the diffusion cylinder 160, during the axial flow along the diffusion cylinder 160, the impact particles are ejected from the diffusion outlet after impacting the impact plate 162, and enter the heat exchange tube 122 along with the flowing medium, i.e., the heat exchange medium. The thickness of the impact plate 162 can be 2cm-4cm.

[0053] Combination Figure 3 and Figure 5 As shown, the diffusion outlet 160a gradually expands in the direction from inside the diffusion cylinder 160 to outside the diffusion cylinder 160, which facilitates the discharge and diffusion of the heat exchange medium containing impact particles.

[0054] The impact plate 162 can be disposed above the diffusion outlet 160a, and the impact plate 162 has a receiving surface that protrudes towards the diffusion inlet, so that the impact particles in the heat exchange medium are refracted and ejected from the diffusion outlet 160a during their journey. The impact particles can be refracted at 90° under the action of the receiving surface. It can be understood that the impact particles moving axially along the diffusion cylinder 160 can move radially along the diffusion cylinder 160 under the action of the receiving surface of the impact plate 162, and are finally discharged from the diffusion outlet. The receiving surface can be a conical surface, and the included angle between two opposing generatrices of the conical surface can be 120°-150°.

[0055] The tube box 14 has a first sidewall 14a and a second sidewall 14b that are opposite to each other. Two sets of connecting ports can be respectively provided on the first sidewall 14a and the second sidewall 14b. It can be understood that each of the first sidewall 14a and the second sidewall 14b can be provided with a set of connecting ports, and each set of connecting ports can include at least one connecting port. The heat exchanger 10 can include a pair of heat exchange bodies 12 respectively provided on the first sidewall 14a and the second sidewall 14b, wherein: heat exchange tubes 122 can be installed in the connecting ports of the corresponding sidewalls; the sidewall of the diffuser cylinder 160 can be provided with a pair of diffusion outlets 160a that are opposite to each other, and the receiving surface can make the impact particles ejected from the corresponding diffusion outlets 160a of the pair of diffusion outlets 160a. By providing a pair of heat exchange bodies 12, the heat exchange efficiency and heat exchange effect of the entire heat exchanger 10 are improved. At the same time, the receiving surface of the impact plate 162 can be used to facilitate the ejection of impact particles into the heat exchange tubes 122 located on both sides of the tube box 14.

[0056] like Figure 2As shown, the first sidewall 14a can be formed as an arcuate surface protruding outward from the cavity 140, which allows the impacting particles to be better ejected into the heat exchange tube 122 located on the side of the first sidewall 14a; in addition, the second sidewall 14b can be formed as an arcuate surface protruding outward from the cavity 140, which allows the impacting particles to be better ejected into the heat exchange tube 122 located on the side of the second sidewall 14b. Preferably, the first sidewall 14a can be an arcuate surface, and the second sidewall 14b can also be an arcuate surface.

[0057] The sidewall of the diffuser cylinder 160 may be provided with multiple pairs of diffusion outlets 160a arranged along the axial direction of the diffuser cylinder 160; the diffusion mechanism 16 may include multiple impact plates 162 disposed inside the diffuser cylinder 160 and corresponding to the corresponding diffusion outlets 160a respectively. That is, the impact plates 162 may be disposed above the corresponding pairs of diffusion outlets 160a. In this way, the impact plates 162 located in each layer can eject the impact particles that impact the impact plates 162 of that layer from the corresponding pairs of diffusion outlets 160a respectively. The impact plates 162 may be provided with gaps 164 for the heat exchange medium to pass through. In this way, after the heat exchange medium passes through the gaps 164, it can continue to flow along the axial direction of the diffuser cylinder 160 and allow the impact particles of the heat exchange medium to continue to impact the next impact plate 162. The impact of the multi-layered impact plates 162 not only causes the impact particles to be ejected into the heat exchange tube 122, but also makes the impact particles more evenly dispersed in the heat exchange tube 122 on the corresponding side of the tube box 14, thereby improving the descaling effect and descaling efficiency.

[0058] To ensure the impact effect of each impact plate 162, the gap 164 between adjacent impact plates 162 is staggered with the gap 164 between the two impact plates. This means that the solid portion of one impact plate 162 corresponds to the hollow portion of the adjacent impact plate 162. Thus, when the heat exchange medium passes through the gap 164 of one impact plate 162, it impacts the solid portion of the next impact plate 162, thereby ensuring the impact effect of each layer of impact plates 162 and allowing the impact particles in the heat exchange medium to be evenly dispersed into the heat exchange tubes 122 on the corresponding side. The end of the diffuser cylinder 160 furthest from the diffuser inlet can be formed as a closed end.

[0059] Preferably, three impact plates 162 can be provided inside the diffusion cylinder 160; the impact plate 162 near the diffusion inlet can be the first impact plate 162a, and the gap 164 of the first impact plate 162a can be provided at the edge of the first impact plate 162a; the impact plate 162 adjacent to the first impact plate 162a can be the second impact plate 162b, and the gap 164 of the second impact plate 162b can be provided at the middle and / or edge of the second impact plate 162b. It is understood that two gaps 164 can be provided on the second impact plate 162b, one gap 164 can be provided at the middle of the second impact plate 162b, and the other gap 164 can be provided at the edge of the second impact plate 162b; while the impact plate 162 located at the end of the diffusion cylinder 160 away from the diffusion inlet can be the third impact plate 162c, the third impact plate 162c can not be provided with gaps 164, and the third impact plate 162c can be a solid structure. By setting the gap 164 between the multiple impact plates 162a as described above, the impact effect can be further improved, so that the impact particles are basically ejected from the diffusion cylinder 160.

[0060] like Figure 1 As shown, a stirring mechanism 18 can be provided in the cavity 140. The stirring mechanism 18 may include a stirring paddle 180 disposed between the diffusion outlet 160a and the communication port. The stirring paddle 180 can agitate the heat exchange medium to drive the impact particles into the communication port, thereby making the impact particles in the heat exchange medium more evenly dispersed in the heat exchange tube 122 on the corresponding side.

[0061] Combination Figure 1 and Figure 6 As shown, the stirring paddle 180 may include a stirring shaft 180a and a stirring body disposed on the stirring shaft 180a. The stirring body may include a plurality of stirring plates 180b disposed along the axial direction of the stirring shaft 180a. The stirring plates 180b may be symmetrically disposed about the stirring shaft 180a. The stirring shaft 180a can drive the plurality of stirring plates 180b to rotate around the axis of the stirring shaft 180a.

[0062] To further improve the agitation effect and ensure that the impacting particles enter the heat exchange tube 122 on the corresponding side more smoothly, the stirring body is formed with a first end and a second end at its two ends along the axial direction of the stirring shaft 180a. The stirring body gradually expands in the direction from the first end toward the middle of the stirring body, and the stirring body also gradually expands in the direction from the second end toward the middle of the stirring body. It can be understood that the distance between the two ends of the stirring plate 180b gradually increases in the direction from the first end to the middle of the stirring body; and the distance between the two ends of the stirring plate 180b gradually increases in the direction from the second end to the middle of the stirring body.

[0063] Additionally, a frame 180c may be provided around the outer periphery of the mixing body. It is understood that the frame 180c may cover the ends of the multiple mixing plates 180b. The frame 180c may be made of plastic.

[0064] like Figure 1 As shown, a manifold 19 can be provided. The manifold 19 has a manifold chamber and a manifold inlet that is connected to the pipe outlet. Thus, the heat exchange medium discharged from the pipe outlet can be collected, which facilitates the discharge of the heat exchange medium.

[0065] The present invention also provides a heat exchange system 20, which includes a heat exchanger 10 and a solid-liquid separator 22 provided by the present invention. The solid-liquid separator 22 is provided with a separation inlet connected to the pipe outlet. The solid-liquid separator 22 can perform solid-liquid separation on the medium discharged from the heat exchange tube 122, i.e., the medium to be heat exchanged after heat exchange. The solid-liquid separator 22 can be provided with a solid outlet for discharging the separated impact particles and a liquid outlet for discharging the separated medium to be heat exchanged. The solid outlet is connected to the diffusion inlet, so that the impact particles can be reused and material waste is reduced.

[0066] Additionally, a particle collection tank 24 can be provided, which may have a particle inlet and a particle outlet for the impact particles to enter and exit respectively. The particle inlet can be connected to the solid discharge outlet, and the particle outlet can be connected to the diffusion inlet. Thus, the solid-liquid separator 22 can be connected to the interior of the diffusion cylinder 160 through the particle collection tank 24. By providing the particle collection tank 24, it is not only convenient to collect the separated impact particles, but also to ensure that the impact particles can smoothly enter the diffusion cylinder 160.

[0067] To facilitate the collection of the liquid separated by the solid-liquid separator 22, i.e. the heat exchange medium after heat exchange, a liquid receiving tank 26 can be provided. The liquid receiving tank 26 has a receiving chamber that can accommodate the heat exchange medium. The liquid receiving tank 26 can be provided with a drain port that discharges the heat exchange medium from the receiving chamber. The drain port can be connected to the diffusion inlet.

[0068] A delivery pipe 27b can be installed between the drain outlet and the diffusion inlet, and a delivery pump 27a can be installed on the delivery pipe 27b. In this way, the delivery pump 27a can pump the liquid in the delivery pipe 27b into the diffusion cylinder 160.

[0069] In addition, a three-way valve 28 can be installed on the delivery pipe 27b. The three ports of the three-way valve 28 can be connected to the liquid outlet, the diffusion inlet and the solid outlet respectively, so that the heat exchange medium and the impact particles can be discharged into the diffusion cylinder 160 in one go.

[0070] This invention also provides a method for descaling heat exchanger tubes, comprising the following steps: introducing a heat exchange medium containing impact particles into the heat exchanger tubes to flush away the scale on the inner wall of the tubes. By introducing the heat exchange medium containing impact particles into the heat exchanger tubes, not only is heat exchange of the heat exchange medium achieved, but the heat exchanger tubes also achieve self-cleaning. This allows for cleaning without shutting down the system, significantly improving operational efficiency.

[0071] Preferably, the heat exchanger 10 provided by the present invention can be used to implement a method for descaling the heat exchanger tubes.

[0072] The material of the impact particles can be selected from at least one of engineering plastics, alumina, stainless steel and zirconium silicate, wherein: engineering plastics can be at least one of polyamide, polycarbonate, polyoxymethylene, polyimide and polysulfone.

[0073] Furthermore, the solid content of the impact particles can be 3%-8%, meaning that the total weight of the impact particles can account for 3%-8% of the total weight of the fluid. The total weight of the fluid is the sum of the total weight of the impact particles and the total weight of the liquid flowing with the impact particles. By setting the solid content of the impact particles within this range, not only is the heat exchange effect on the heat exchange medium guaranteed, but also the flushing effect of the impact particles on fouling is ensured.

[0074] To further improve the scouring effect of the impact particles, the average particle size of the impact particles can be set to 2-4 mm.

[0075] In addition, the flow velocity of the fluid inside the heat exchange tube can be set between 1.2 m / s and 3.5 m / s, which can further improve the heat exchange effect of the heat exchange medium and further improve the flushing effect of the impact particles on the fouling.

[0076] The effects of the present invention will be further illustrated below through examples and comparative examples.

[0077] Example

[0078] Examples 1-14

[0079] The heat exchanger 10 provided by this invention exchanges heat with the crude oil discharged from the condenser of the crude oil cracking catalytic unit. It includes a pair of heat exchange bodies 12, each containing 647 heat exchange tubes 122. Each heat exchange tube 122 is 1200 mm long, has an outer diameter of 25 mm, and a wall thickness of 2.5 mm. The initial flow velocity within the heat exchange tubes 122 is 2.2 m / s. The tube box 14 is cylindrical, with both the first sidewall 14a and the second sidewall 14b having arc surfaces and a thickness of 2 cm. The diffuser cylinder 160 has three pairs of diffusion outlets 160a. a gradually expands in the direction from inside the diffuser cylinder 160 to outside the diffuser cylinder 160; it is equipped with three impact plates 162, the gap 164 of the first impact plate 162a is set at the edge of the first impact plate 162a, the first gap 164 of the second impact plate 162b is set at the middle of the second impact plate 162b, the second gap 164 of the second impact plate 162b is set at the edge of the second impact plate 162b, the second impact plate 162b is a solid structure and does not have gaps 164, and the material-facing surface of the impact plate 162 is a conical surface. The following are the characteristics of the impact particles carried by the crude oil, including their material, average particle size, solid content, diameter of the tube box 14, length of the tube box 14, diameter of the stirring shaft 180a of the agitator 180, rotational speed of the stirring shaft 180a, perimeter of the enclosure 180c, and number of stirring plates 180b: Table 1 shows the following characteristics. The percentage of the solid portion of the impact plate 162 occupying the corresponding total area of ​​the impact plate (only the first impact plate 162a and the second impact plate 162b are shown), the included angle between the two generatrices of the conical surface of the impact plate 162, the inner diameter of the diffuser cylinder 160, the small diameter of the diffuser outlet 160a, the large diameter of the diffuser outlet 160a, and the ratio of the dispersion coefficient and heat transfer coefficient of the impact particles after 180 days of continuous operation under the corresponding conditions to the heat transfer coefficient when the tube box 14 and the diffuser mechanism 16 are not installed: Table 2 shows the following characteristics.

[0080] Table 1

[0081]

[0082] Table 2

[0083]

[0084] Note: The dispersion coefficient of impact particles refers to the degree to which solid particles that have diffused into each heat exchange tube are evenly distributed in the heat exchange tube; the heat transfer system ratio refers to the ratio of the heat transfer coefficient calculated after the heat exchanger has been running for 180 days to the heat transfer coefficient calculated when the heat exchanger was first running. The heat transfer coefficient can be understood as the heat exchange efficiency of the heat exchanger. The higher the value, the better the heat exchange efficiency.

[0085] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A heat exchanger, characterized in that, The heat exchanger (10) includes: The heat exchange body (12) includes a heat exchange shell (120) and a heat exchange tube (122) disposed in the heat exchange shell (120). The two ends of the heat exchange tube (122) are respectively formed as a tube inlet and a tube outlet for the heat exchange medium to be exchanged. The heat exchange shell (120) is provided with a shell inlet and a shell outlet for the heat exchange medium to exchange heat with the heat exchange medium to be exchanged. The tube box (14) has a cavity (140). The tube box (14) is provided with a communication port that is connected to the tube inlet and a tube box inlet for the heat exchange medium containing impact particles to enter the cavity (140). The heat exchange body (12) is located outside the cavity (140). The tube box (14) has a first sidewall (14a) and a second sidewall (14b) opposite to each other, and two sets of connecting ports are respectively provided on the first sidewall (14a) and the second sidewall (14b). Each set of connecting ports includes at least one of the connecting ports. The heat exchanger (10) includes a pair of heat exchange bodies (12) respectively provided on the first sidewall (14a) and the second sidewall (14b), wherein the heat exchange tube (122) is installed in the connecting port of the corresponding sidewall. The first sidewall (14a) is formed as an arcuate surface protruding outward from the cavity (140), and / or, the second sidewall (14b) is formed as an arcuate surface protruding outward from the cavity (140); and A diffusion mechanism (16) is disposed in the cavity (140) and is configured to allow impact particles in the heat exchange medium to be ejected into the heat exchange tube (122).

2. The heat exchanger according to claim 1, characterized in that, The diffusion mechanism (16) includes: A diffusion cylinder (160) is disposed within the cavity (140), the diffusion cylinder (160) having a diffusion inlet communicating with the inlet of the tube box and a diffusion outlet (160a) for discharging the impact particles; and Impact plate (162), which is disposed inside the diffusion cylinder (160), is configured to eject the impact particles entering from the diffusion inlet out of the diffusion outlet (160a).

3. The heat exchanger according to claim 2, characterized in that, The diffusion inlet is located at the end of the diffusion cylinder (160), the diffusion outlet (160a) is located on the side wall of the diffusion cylinder (160), and the diffusion outlet (160a) is located facing the communication port. The impact plate (162) is disposed above the diffusion outlet (160a), and the impact plate (162) has a material-facing surface that bulges toward the diffusion inlet so that the impact particles in the heat exchange medium are refracted and ejected from the diffusion outlet (160a) during their journey.

4. The heat exchanger according to claim 3, characterized in that, The sidewall of the diffusion cylinder (160) is provided with a pair of diffusion outlets (160a) that are opposite to each other, and the receiving surface enables the impact particles to be ejected from the corresponding diffusion outlet (160a) of the pair of diffusion outlets (160a).

5. The heat exchanger according to claim 4, characterized in that, The sidewall of the diffusion cylinder (160) is provided with multiple pairs of diffusion outlets (160a) arranged along the axial direction of the diffusion cylinder (160). The diffusion mechanism (16) includes a plurality of impact plates (162) disposed inside the diffusion cylinder (160) and corresponding to the respective diffusion outlets (160a). The impact plates (162) are provided with gaps (164) for the heat exchange medium to pass through.

6. The heat exchanger according to claim 5, characterized in that, In the adjacent impact plates (162), the gap (164) of one impact plate (162) is staggered from the gap (164) of the other impact plate (162); The impact plate (162) near the diffusion inlet is a first impact plate (162a), and the gap (164) of the first impact plate (162a) is provided at the edge of the first impact plate (162a). The impact plate (162) adjacent to the first impact plate (162a) is a second impact plate (162b), and the gap (164) of the second impact plate (162b) is provided at the middle and / or edge of the second impact plate (162b).

7. The heat exchanger according to claim 2, characterized in that, The diffusion outlet (160a) is gradually widening in the direction from inside the diffusion cylinder (160) to outside the diffusion cylinder (160).

8. The heat exchanger according to claim 2, characterized in that, The heat exchanger (10) includes a stirring mechanism (18) disposed in the cavity (140). The stirring mechanism (18) includes a stirring paddle (180) disposed between the diffusion outlet (160a) and the communication port. The stirring paddle (180) can agitate the heat exchange medium to drive the impact particles into the communication port.

9. The heat exchanger according to claim 8, characterized in that, The stirring paddle (180) includes a stirring shaft (180a) and a stirring body disposed on the stirring shaft (180a). The stirring body includes a plurality of stirring plates (180b) disposed along the axial direction of the stirring shaft (180a). The stirring plates (180b) are symmetrically disposed about the stirring shaft (180a). The stirring shaft (180a) can drive the plurality of stirring plates (180b) to rotate around the axis of the stirring shaft (180a).

10. The heat exchanger according to claim 9, characterized in that, The stirring paddle (180) includes a frame (180c) surrounding the outer periphery of the stirring body; and / or The stirring body is formed at two ends along the axial direction of the stirring shaft (180a) as a first end and a second end, respectively. The stirring body is gradually expanding in the direction from the first end toward the middle of the stirring body, and the stirring body is gradually expanding in the direction from the second end toward the middle of the stirring body.

11. The heat exchanger according to any one of claims 1-10, characterized in that, The tube box (14) is provided with a plurality of the communication ports, and the heat exchanger (10) includes a plurality of heat exchange tubes (122) respectively installed in the corresponding communication ports. The heat exchanger (10) includes a manifold (19) having a manifold chamber and a manifold inlet connected to the pipe outlet.

12. A heat exchange system, characterized in that, The heat exchange system (20) includes the heat exchanger (10) as described in any one of claims 2-10, and also includes a solid-liquid separator (22). The solid-liquid separator (22) is provided with a separation inlet connected to the tube outlet. The solid-liquid separator (22) is capable of performing solid-liquid separation on the medium discharged from the heat exchange tube (122). The solid-liquid separator (22) is provided with a solid outlet for discharging the separated impact particles and a liquid outlet for discharging the separated heat exchange medium. The solid discharge outlet is connected to the diffusion inlet.

13. The heat exchange system according to claim 12, characterized in that, The heat exchange system (20) includes a particle receiving tank (24), which is provided with a particle inlet and a particle outlet for impact particles to enter and exit, respectively. The particle inlet is connected to the solid discharge outlet, and the particle outlet is connected to the diffusion inlet; and / or The heat exchange system (20) includes a liquid receiving tank (26), which has a receiving chamber capable of containing the heat exchange medium to be exchanged. The liquid receiving tank (26) is provided with a drain outlet for discharging the heat exchange medium from the receiving chamber, and the drain outlet is connected to the diffusion inlet.

14. A method for descaling heat exchanger tubes, said descaling method being applicable to the heat exchanger (10) as described in any one of claims 1-11, characterized in that, The descaling method for the heat exchanger tubes includes the following steps: A heat exchange medium containing impact particles is introduced into the heat exchange tubes of the heat exchanger to flush away the dirt on the inner wall of the heat exchange tubes.

15. The method for descaling heat exchanger tubes according to claim 14, characterized in that, The impact particles are made of at least one of engineering plastics, alumina, stainless steel, and zirconium silicate; and / or The solid content of the impact particles is 3%-8%.

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