Eccentric spiral heat exchanger

Abstract

The utility model discloses an eccentric spiral heat exchanger which comprises a shell, a hollow pipe, a plurality of heat exchange pipes and a plurality of layers of supporting assemblies. The eccentric type spiral heat exchanger has the advantages that the starting end of the heat exchange pipe is led out from the cold water end and is coiled into a spiral shape along the outer wall of the hollow pipe, the spiral structure increases the heat exchange area, the contact time of hot smoke and heat exchange media is longer, and the heat exchange efficiency is improved; 2, the hollow pipe is close to the upper part in the cavity and is eccentrically arranged, so that the upper part of the outer side of the heat exchange pipe is close to the inner wall of the shell, a larger gap is formed between the lower part of the outer side of the heat exchange pipe and the inner wall of the shell, and dust at the larger gap below can be quickly taken away by wind speed generated when hot smoke passes through the shell so as to avoid dust accumulation in the shell; and 3, the heat exchange tube is formed by hot bending of a light tube, the number of structural parts is small, the number of required welding parts is small, the manufacturing cost is reduced, and the light tube of the heat exchange tube is easy to maintain and clean.

Description

Technical Field

[0001] This utility model relates to the field of heat exchange equipment technology, specifically to an eccentric spiral heat exchanger. Background Technology

[0002] In thermal power plants, efficient utilization of thermal energy is crucial to power generation efficiency, yet flue gas heat exchangers present numerous problems. Traditional products suffer from low heat exchange efficiency, with significant heat loss through exhaust gas and cooling media, resulting in reduced power plant thermal efficiency and increased costs. Ash accumulation is widespread, with fly ash adhering to the flue gas and forming an insulating layer, weakening heat exchange effects, making cleaning cumbersome, and causing frequent shutdowns that impact power generation and shorten equipment lifespan. Furthermore, their complex structure, with numerous internal components and pipes, makes assembly and maintenance difficult, inconvenient for workers, and incurring high maintenance costs. Today, the power industry is rapidly moving towards large-scale units and high-parameter operation, placing increasingly stringent demands on the performance of flue gas heat exchangers. There is an urgent need for new heat exchangers that are highly efficient, structurally reliable, and easy to maintain to meet the current and future development needs of thermal power generation. Therefore, this utility model aims to propose an eccentric spiral heat exchanger. Utility Model Content

[0003] In order to overcome the technical problems described in the prior art, the purpose of this utility model is to provide an eccentric spiral heat exchanger.

[0004] This utility model discloses an eccentric spiral heat exchanger, comprising a shell with an internal cylindrical cavity, a hollow tube disposed within the cavity, and a cold water cavity and a hot water cavity within the hollow tube; it also includes several heat exchange tubes, the starting ends of which extend from the cold water end and are spirally wound along the outer wall of the hollow tube, and the ends of which are bent and connected to the hot water end; it also includes several layers of support assemblies for fixing the inner wall of the shell and the outer wall of the hollow tube, with one heat exchange tube sandwiched between adjacent layers of support assemblies; wherein, the hollow tube is eccentrically positioned near the upper part of the cavity, so that the upper outer part of the heat exchange tube is close to the inner wall of the shell, while the lower outer part of the heat exchange tube has a large gap with the inner wall of the shell.

[0005] As a preferred technical solution, any layer of support assembly includes at least four sets of support rods, which are evenly distributed on the outer wall of the hollow tube, and the two ends of any one of the support rods are respectively fixed to the inner wall of the shell and the outer wall of the central cylinder.

[0006] As a preferred technical solution, the support rod is spot-welded to the heat exchange tube to ensure the stability of clamping the heat exchange tube.

[0007] As a preferred technical solution, the hollow tube is provided with a long partition, which divides the interior of the hollow tube into adjacent cold water chambers and hot water chambers, so that the hot water chambers can preheat the cold water chambers.

[0008] As a preferred technical solution, the eccentric spiral heat exchanger further includes an inlet pipe connected to the cold water chamber and an outlet pipe connected to the hot water chamber.

[0009] As a preferred technical solution, the top of the hot water chamber is provided with an exhaust pipe for venting air from the hollow tube.

[0010] As a preferred technical solution, the end of the heat exchange tube is first bent to the front or rear of the coiled layer so as not to interfere with the spiral structure of the heat exchange tube.

[0011] As a preferred technical solution, the heat exchange tube is a smooth tube with a smooth outer wall to prevent dust accumulation.

[0012] As a preferred technical solution, the heat exchange tube is manufactured by a hot bending forming process.

[0013] As a preferred technical solution, the eccentric spiral heat exchanger is used for waste heat recovery and reuse of flue gas in thermal power plants.

[0014] In summary, this utility model has the following technical effects:

[0015] This utility model discloses an eccentric spiral heat exchanger, which includes a shell, a hollow tube, several heat exchange tubes, and several layers of support assemblies. The shell has a cylindrical cavity inside, and the hollow tube is disposed in the cavity. The hollow tube has a cold water cavity and a hot water cavity inside. The starting end of the heat exchange tube is led out from the cold water end and coiled into a spiral shape along the outer wall of the hollow tube. The end of the heat exchange tube is bent and connected to the hot water end. The support assemblies are used to fix the inner wall of the shell and the outer wall of the hollow tube. A heat exchange tube is sandwiched between two adjacent layers of support assemblies. The hollow tube is eccentrically positioned near the upper part of the cavity, so that the upper outer part of the heat exchange tube is close to the inner wall of the shell, and there is a gap between the lower outer part of the heat exchange tube and the inner wall of the shell. The eccentric spiral heat exchanger with the above-described structure has the following technical advantages: 1. The heat exchange tube of this invention starts from the cold water end and coils into a spiral shape along the outer wall of the hollow tube. The spiral structure increases the heat exchange area, allowing the hot flue gas to contact the heat exchange medium for a longer time, thus improving heat exchange efficiency. 2. The hollow tube of this invention is eccentrically positioned near the upper part of the cavity, so that the upper outer part of the heat exchange tube is close to the inner wall of the shell, while the lower outer part of the heat exchange tube has a large gap with the inner wall of the shell. The wind speed generated when the hot flue gas passes through the shell can quickly carry away the dust in the larger gap below to avoid dust accumulation inside the shell. 3. The heat exchange tube of this invention is formed by hot bending of a smooth tube, resulting in fewer structural components and fewer welding points, thereby reducing manufacturing costs. At the same time, the smooth tube is easy to maintain and clean, reducing the operating costs of thermal power plants. Therefore, compared with existing thermal power plant heat exchanger technologies, the eccentric spiral heat exchanger provided by this invention has significant technical advantages. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural schematic diagram of an eccentric spiral heat exchanger provided in some embodiments;

[0018] Figure 2 This is a front view schematic diagram of an eccentric spiral heat exchanger provided in some embodiments;

[0019] Figure 3 This is a three-dimensional structural diagram of a heat exchange tube and a hollow tube provided in some embodiments;

[0020] Figure 4 These are schematic diagrams of the hollow tube provided in some embodiments;

[0021] The meanings of the reference numerals in the attached figures are as follows:

[0022] 1-Shell, 2-Hollow tube, 21-Long partition, 3-Heat exchange tube, 31-Starting end, 32-Ending end, 4-Support rod, 51-Water inlet pipe, 52-Water outlet pipe, 6-Exhaust pipe. Detailed Implementation

[0023] The technical solution of this embodiment will be clearly and completely described below with reference to the accompanying drawings. The embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. Therefore, it should be understood that various modifications and changes can be made to this embodiment without departing from the scope of protection of this utility model.

[0024] In the description of this invention, unless otherwise expressly specified and limited, the term "and / or" includes any and all combinations of one or more of the associated listed items. Unless otherwise specified or stated, the terms "connection," "fixed," etc., should be interpreted broadly; for example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art will understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] Furthermore, in the description of this utility model, it should be understood that the directional terms described in this embodiment are used to describe the angles shown in the accompanying drawings and should not be construed as limiting this embodiment. It should also be understood that, in the context, when an element or feature is mentioned as being connected to another element (one or more), it can be connected not only directly to the other element (one or more) but also indirectly to the other element (one or more) through an intermediate element.

[0026] Before introducing the technical solution of this utility model, it is necessary to explain the background of its invention. It is a common problem in thermal power plants where efficient utilization of thermal energy is crucial to power generation efficiency, yet flue gas heat exchangers suffer from numerous issues. Traditional products have low heat exchange efficiency, with a large amount of heat energy lost with the exhaust gas and cooling medium, resulting in reduced power plant thermal efficiency and increased costs. Ash accumulation is widespread, with flue gas fly ash adhering to form an insulating layer, weakening the heat exchange effect. Ash cleaning is cumbersome, and frequent shutdowns affect power generation and shorten equipment lifespan. Furthermore, the complex structure, with numerous internal components and pipes, makes assembly and maintenance difficult, inconvenient for workers, and results in high maintenance costs.

[0027] Please see Figures 1 to 3 An exemplary embodiment of this utility model provides an eccentric spiral heat exchanger, comprising a shell 1, a hollow tube 2, a plurality of heat exchange tubes 3, and a plurality of supporting assemblies. The shell 1 has a cylindrical cavity inside, and the hollow tube 2 is disposed within the cavity, containing a cold water chamber and a hot water chamber. The starting end 31 of the heat exchange tube 3 extends from the cold water end and coils into a spiral shape along the outer wall of the hollow tube 2. The ending end 32 of the heat exchange tube 3 is bent and connected to the hot water end. The supporting assemblies are used to fix the inner wall of the shell 1 and the outer wall of the hollow tube 2, with a heat exchange tube 3 sandwiched between adjacent supporting assemblies. The hollow tube 2 is eccentrically positioned near the upper part of the cavity, so that the upper outer part of the heat exchange tube 3 is close to the inner wall of the shell 1, while a gap exists between the lower outer part of the heat exchange tube 3 and the inner wall of the shell 1. It should be understood that the eccentric spiral heat exchanger is applied to the recovery and reuse of waste heat from flue gas in thermal power plants. As can be seen, the eccentric spiral heat exchanger of this utility model refers to the heat exchange tube 3 being eccentrically positioned towards the upper part of the shell 1 along with the central tube, so that there is a certain gap between the lower part of the outer side of the heat exchange tube 3 and the inner wall of the shell 1. It should be understood that when the high-temperature exhaust gas generated by the power plant passes through the shell 1 of this eccentric spiral heat exchanger, the wind speed at the gap will be greater than at other locations because there are no other components blocking it. This will allow the dust that falls into the gap during the heat exchange process to be quickly carried away to avoid dust accumulation inside the shell 1.

[0028] In some embodiments, please refer to Figure 1 and Figure 2Each layer of the support assembly includes at least four sets of support rods 4, which are evenly distributed on the outer wall of the hollow tube 2. Each support rod 4 is fixed at both ends to the inner wall of the shell 1 and the outer wall of the central cylinder, respectively. Specifically, in this embodiment, one layer of the support assembly includes four sets of support rods 4, which are arranged in a cross shape on the outer wall of the hollow tube 2 to support the hollow tube 2. The support rods 4 are preferably welded to the outer wall of the hollow tube 2, and also preferably welded to the inner wall of the shell 1. It should be noted that since the hollow tube 2 is eccentrically positioned (its center is not located at the center of the cylindrical cavity), the four sets of support rods 4 have different lengths. As a preferred technical solution, the support rods 4 are spot-welded to the heat exchange tube 3. This design ensures the fixation of the heat exchange tube 3 to guarantee its wind-facing rigidity, i.e., the stability of clamping the heat exchange tube 3. It should be noted that, as a preferred technical solution, such as... Figure 3 As shown, the end 32 of the heat exchange tube 3 is first bent to the front or rear of the coiled layer so as not to interfere with the spiral structure of the heat exchange tube 3.

[0029] Please see Figure 1 , Figure 2 and Figure 4 As a preferred technical solution, the eccentric spiral heat exchanger further includes an inlet pipe 51 connected to the cold water chamber and an outlet pipe 52 connected to the hot water chamber. Preferably, the hollow tube 2 is provided with a long partition 21, which divides the interior of the hollow tube 2 into adjacent cold water chambers and hot water chambers, so that the hot water chamber can preheat the cold water chamber. This design allows the low-temperature heat exchange medium to enter the cold water chamber of the hollow tube 2 from the inlet pipe 51, then flow through the heat exchange tube 3 for heat exchange. After the heat exchange is completed, the heat exchange medium flows through the hot water chamber of the hollow tube 2 and exits through the outlet pipe 52 for the next stage of heat utilization. The proximity of the cold water chamber and the hot water chamber allows the hot water chamber to raise the initial temperature of the heat exchange medium in the cold water chamber to a certain extent, preventing the heat exchange tube 3 from condensing due to the low initial temperature of the heat exchange medium encountering high-temperature residual smoke, which could then trap dust from the high-temperature residual smoke and cause ash accumulation.

[0030] Please see Figure 1 and Figure 2 As a preferred technical solution, the top of the hot water chamber is equipped with an exhaust pipe 6 for venting air from the hollow tube 2. This design aims to ensure that the eccentric spiral heat exchanger, both during initial operation and after shutdown, vents the air inside the hollow tube 2 to guarantee heat exchange efficiency and safe operation. The exhaust pipe is installed at the highest point of the hot water chamber inside the hollow tube 2 to ensure complete air removal.

[0031] As a preferred technical solution, the heat exchange tube 3 is a smooth tube with a smooth outer wall to prevent dust accumulation and facilitate maintenance and cleaning. Furthermore, the heat exchange tube 3 is manufactured by a hot bending forming process. Using a smooth tube for hot bending reduces the number of structural components in the heat exchange tube 3 and the amount of welding required, thereby reducing manufacturing costs.

[0032] In summary, the eccentric spiral heat exchanger of this utility model has the following technical advantages:

[0033] 1. The heat exchange tube of this invention starts from the cold water end and is coiled into a spiral shape along the outer wall of the hollow tube. The spiral structure increases the heat exchange area, allowing the hot flue gas to contact the heat exchange medium for a longer time, thus improving the heat exchange efficiency. 2. The hollow tube of this invention is eccentrically positioned near the upper part of the cavity, so that the upper outer part of the heat exchange tube is close to the inner wall of the shell, while there is a large gap between the lower outer part of the heat exchange tube and the inner wall of the shell. The wind speed generated when the hot flue gas passes through the shell can quickly carry away the dust in the larger gap below to avoid dust accumulation inside the shell. 3. The heat exchange tube of this invention is formed by hot bending of a smooth tube, which reduces the number of structural components and welding points, thereby reducing manufacturing costs. At the same time, the smooth tube is easy to maintain and clean, reducing the operating costs of thermal power plants.

[0034] Therefore, compared with existing heat exchanger technology for thermal power plants, the eccentric spiral heat exchanger provided by this utility model has obvious technical advantages.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such 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.

Claims

1. An eccentric spiral heat exchanger, characterized in that, The device includes a shell with an internal cylindrical cavity, within which a hollow tube is provided. The hollow tube contains a cold water cavity and a hot water cavity. It also includes several heat exchange tubes, each with its starting end extending from the cold water cavity and spirally coiled along the outer wall of the hollow tube. The ends of the heat exchange tubes are bent and connected to the hot water cavity. Furthermore, it includes several layers of support assemblies for fixing the inner wall of the shell and the outer wall of the hollow tube, with one heat exchange tube sandwiched between adjacent layers of support assemblies. The hollow tube is eccentrically positioned near the upper part of the cavity, such that the upper outer part of the heat exchange tube is close to the inner wall of the shell, while a gap exists between the lower outer part of the heat exchange tube and the inner wall of the shell.

2. An eccentric spiral heat exchanger according to claim 1, characterized in that, Each layer of the support assembly includes at least four sets of support rods, which are evenly distributed on the outer wall of the hollow tube, and the two ends of each support rod are respectively fixed to the inner wall of the shell and the outer wall of the hollow tube.

3. An eccentric spiral heat exchanger according to claim 2, characterized in that, The support rod is spot-welded to the heat exchange tube to ensure the stability of clamping the heat exchange tube.

4. An eccentric spiral heat exchanger according to claim 3, characterized in that, The hollow tube is equipped with a long partition, which divides the interior of the hollow tube into adjacent cold water chambers and hot water chambers, so that the hot water chambers can preheat the cold water chambers.

5. An eccentric spiral heat exchanger according to claim 4, characterized in that, The eccentric spiral heat exchanger also includes an inlet pipe connected to the cold water chamber and an outlet pipe connected to the hot water chamber.

6. An eccentric spiral heat exchanger according to claim 5, characterized in that, The top of the hot water chamber is equipped with an exhaust pipe for venting air from the hollow tube.

7. An eccentric spiral heat exchanger according to claim 6, characterized in that, The end of the heat exchange tube is first bent to the front or rear of the coiled layer so as not to interfere with the spiral structure of the heat exchange tube.

8. An eccentric spiral heat exchanger according to claim 7, characterized in that, The heat exchange tube is a smooth tube with a smooth outer wall to prevent dust accumulation.

9. An eccentric spiral heat exchanger according to claim 1, characterized in that, The heat exchange tube is manufactured using a hot bending forming process.

10. An eccentric spiral heat exchanger according to any one of claims 1-9, characterized in that, The eccentric spiral heat exchanger is used for waste heat recovery and reuse of flue gas in thermal power plants.

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