A low temperature electric heating heat exchange device

Abstract

This invention discloses a low-temperature electric heating heat exchange device, belonging to the technical field of low-temperature medium heating. It includes a heat exchanger shell, within which a heat exchange medium flows. It also includes a coil assembly disposed inside the heat exchanger shell, through which the low-temperature medium flows. The coil assembly has a pre-reserved hollow cavity. The exterior of the heat exchanger shell has a cryogenic medium inlet and a cryogenic medium outlet, both of which are respectively connected to the two ends of the coil assembly. Furthermore, it includes an electric heating rod disposed on the heat exchanger shell, extending into and penetrating the hollow cavity, to achieve the purpose of heating or vaporizing the low-temperature medium while ensuring stable operation of the equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of low-temperature medium heating, and in particular, relates to a low-temperature electric heating heat exchange device. Background Art

[0002] Cryogenic fluids usually refer to fluids with a boiling point below 120 Kelvin (abbreviated K), which is about minus 153 degrees Celsius. Cryogenic fluid heating is different from conventional fluid heating in that: on the one hand, the heating amount must be strictly controlled, and the heat provided by the heater and the heat absorbed by the cryogenic fluid must be accurately calculated; on the other hand, the heating must be uniform, otherwise the cryogenic fluid is prone to vaporization, causing the risk of overpressure.

[0003] Existing cryogenic fluid heating equipment is mainly used for the gas supply of hydrogen-oxygen fuel cells on vehicles, ships, submersibles, etc., the gas supply of vehicle-mounted LNG gas engines, and small-flow cryogenic fluid industrial gas devices.

[0004] The existing low-temperature fluid heating equipment mainly has the following defects:

[0005] (1) The equipment has a large size, and the thermal expansion and contraction deformation and stress caused by the temperature difference after the low-temperature medium enters the equipment are more obvious;

[0006] (2) During the operation of existing equipment, the volatilization of heat exchange medium is relatively large, especially in special environments, the heat exchange medium solution will decrease over time;

[0007] (3) The heating of the heat exchange medium inside the existing equipment is uneven, resulting in poor heating effect on the low-temperature medium. Summary of the invention

[0008] In view of this, in order to solve the above problems existing in the prior art, the purpose of the present invention is to provide a low-temperature electric heating heat exchange device to achieve the purpose of heating or vaporizing the low-temperature medium and ensuring the stable operation of the equipment.

[0009] The technical solution adopted by the present invention is: a low-temperature electric heating heat exchange device, including a heat exchanger shell, in which a heat exchange medium flows, and also includes a coil group arranged inside the heat exchanger shell and through which a low-temperature medium flows, a hollow cavity is reserved in the coil group, and a cryogenic medium inlet and a cryogenic medium outlet are provided on the outside of the heat exchanger shell and the two end ports of the coil group are respectively connected; it also includes an electric heating rod arranged on the heat exchanger shell, and the electric heating rod extends into and passes through the hollow cavity.

[0010] Furthermore, the coil group includes multiple layers of coils, each layer of coils is configured as a spiral structure and each layer of coils is located on the same axis, and the inlet end and the outlet end of each layer of coils are connected to form the cryogenic medium inlet and the cryogenic medium outlet respectively, and the overlapping spiral structure greatly improves the utilization rate of the coil area, thereby reducing the overall dimensions of the equipment.

[0011] Furthermore, it also includes a fixing plate arranged in the heat exchanger shell, the fixing plate is provided with a plurality of fixing holes, each fixing hole is arranged along the longitudinal direction and the transverse direction, each fixing hole located in the same longitudinal direction corresponds to each layer of coils respectively, and each fixing hole located in the same transverse direction matches the spiral shape of the same layer of coils respectively, so as to firmly install each coil and avoid deformation damage caused by thermal expansion and contraction.

[0012] Furthermore, a connecting plate is provided on one side of the fixing plate and the connecting plate matches the inner wall of the heat exchanger shell, and a plurality of hollow holes are opened on the fixing plate, each of which can realize lightweight design and reduce stress concentration.

[0013] Furthermore, it also includes a liquid level meter arranged on the heat exchanger shell, and the probe of the liquid level meter extends into the interior of the heat exchanger shell to monitor the liquid level height of the heat exchange medium in the heat exchanger shell in real time.

[0014] Furthermore, it also includes an automatic exhaust valve, one end of which is connected to the interior of the heat exchanger shell through an inverted cone spiral condenser, ensuring the safe operation of the equipment and avoiding the repeated addition of heat exchange medium in the equipment in a very short time.

[0015] Furthermore, it also includes a temperature transmitter arranged on the heat exchanger shell, and the probe of the temperature transmitter extends into the heat exchange medium inside the heat exchanger shell to monitor the temperature of the heat exchange medium in the heat exchanger shell in real time.

[0016] Furthermore, the heat exchanger shell is provided with a heat exchange medium inlet pipe and a heat exchange medium overflow pipe which are communicated with the interior thereof, and one end of the heat exchange medium overflow pipe extends into the top of the heat exchanger shell to timely overflow the heat exchange medium in the heat exchanger shell.

[0017] Furthermore, the heat exchanger shell includes a cylindrical body and elliptical heads sealed at both ends of the cylindrical body. The coil group is placed on the central axis of the cylindrical body or below the central axis, and the electric heating rod is placed on the central axis of the coil group to achieve uniform and stable heating of the multi-layer coil by the electric heating rod.

[0018] Furthermore, the heat exchange medium adopts ethylene glycol solution, and the ethylene glycol solution can match different low-temperature media.

[0019] The beneficial effects of the present invention are:

[0020] 1. The low-temperature electric heating heat exchange device adopted in the present invention circulates a low-temperature medium in the coil group. At the same time, the heat exchange medium circulates in the heat exchanger shell, and the electric heating rod runs through the coil group to achieve uniform heating of the heat exchange medium. The heated heat exchange medium transfers heat to the low-temperature medium to achieve the effect of heating or gasifying the low-temperature medium. Due to reasonable design optimization, it is mainly used for small or medium flow hydrogen and oxygen fuel cells, LNG gas engine fuel, or low-temperature fluid industrial gas supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the low-temperature electric heating heat exchange device disclosed in the present invention;

[0022] Figure 2 It is a schematic diagram of the internal structure of the low-temperature electric heating heat exchange device disclosed in the present invention;

[0023] Figure 3 It is a schematic diagram of the assembly structure of the coil group in the low-temperature electric heating heat exchange device disclosed in the present invention;

[0024] Figure 4 yes Figure 3 A top view schematic diagram of

[0025] Figure 5 It is a structural schematic diagram of a fixed plate in the low-temperature electric heating heat exchange device disclosed in the present invention;

[0026] The following are marked in the attached figure:

[0027] 1-heat exchanger shell, 2-electric heating rod, 3-liquid level gauge, 4-automatic exhaust valve, 5-temperature transmitter, 6-inverted cone spiral condenser, 7-heat exchange medium inlet pipe, 8-heat exchange medium overflow pipe, 9-cryogenic medium inlet, 10-cryogenic medium outlet, 11-support frame, 12-coil group, 13-coil, 14-fixing plate, 15-connecting plate, 16-hollow hole, 17-fixing hole. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0032] In the description of the embodiments of the present invention, it should be noted that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the invention product is usually placed when in use, or the orientation or positional relationship commonly understood by those skilled in the art, or the orientation or positional relationship in which the invention product is usually placed when in use, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0033] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances; the drawings in the embodiments are used to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations.

[0034] Example 1

[0035] In this embodiment, a low-temperature electric heating heat exchange device is specifically disclosed, which is mainly composed of an electric heating rod 2, a heat exchanger shell 1, a coil group 12, a liquid level meter 3, an automatic discharge valve, a temperature transmitter 5, etc., so as to realize the gasification or heating function of the low-temperature medium. The specific design is as follows:

[0036] like Figure 1 , Figure 2As shown, the heat exchanger shell 1 is used as the carrier of the device and the heat exchanger shell 1 is set to be cylindrical. Preferably, the heat exchanger shell includes a cylindrical body and elliptical heads sealed and assembled at both ends of the cylindrical body, the coil group is placed on the central axis of the cylindrical body or below the central axis, and an automatic exhaust valve, a liquid level meter and a temperature transmitter are arranged on the top of the cylindrical body.

[0037] A heat exchange medium inlet pipe 7 and a heat exchange medium overflow pipe 8 are provided on the heat exchanger shell 1, which are communicated with the interior thereof, so that the heat exchange medium is input into the heat exchanger shell 1 through the heat exchange medium inlet pipe 7. The heat exchange medium inlet pipe 7 is best arranged in the middle and upper part of the heat exchanger shell 1, and one end of the heat exchange medium overflow pipe 8 extends to the top of the heat exchanger shell 1. When the heat exchange medium in the heat exchanger shell 1 is input too much and is about to fill the entire heat exchanger shell 1, the heat exchange medium will overflow through the port of the heat exchange medium overflow pipe 8 to prevent safety accidents.

[0038] The heat exchanger shell 1 also includes a coil group 12 arranged inside the heat exchanger shell 1 and a low-temperature medium flows through the coil group 12, that is, the low-temperature medium flows in the coil group 12, and a hollow cavity is reserved in the coil group 12, and the hollow cavity serves as a reserved position for installing the electric heating rod 2. The outside of the heat exchanger shell 1 is provided with a cryogenic medium inlet 9 and a cryogenic medium outlet 10, and the two are respectively connected to the two end ports of the coil group 12, and the two end ports are the inlet end and the outlet end of the coil group 12 respectively; it also includes an electric heating rod 2 arranged on the heat exchanger shell 1, and the electric heating rod 2 extends into and passes through the hollow cavity to ensure that the coil group 12 can be heated by the electric heating rod 2 in the length direction. In actual application, in order to achieve uniform and stable heating of the coil group 12 on all sides, the electric heating rod 2 is located on the middle axis of the coil group 12. Among them, each layer of coil 13 can be processed by a pipe bending machine with a special device, and for the design of the coil group 12, in actual application, a variety of methods can be adopted, for example: the coil group 12 includes coils 13 arranged along the top, bottom, left and right, and each of the coils 13 is set to a snake-shaped plane structure, so that a rectangular ring frame is formed by each of the coils 13, and the hollow cavity is inside the ring frame. Under the action of the electric heating rod 2, the surroundings of each of the coils 13 can be evenly heated.

[0039] In order to further improve the space utilization of the coil group 12 and reduce the overall size of the equipment, Figure 3 , Figure 4As shown, the coil group 12 includes multiple layers of coils 13, each layer of coils 13 is set as a spiral structure and each layer of coils 13 is located on the same axis. The spiral radius of each layer of coils 13 is different and arranged in sequence from small to large according to the spiral radius of each layer of coils 13, so as to achieve a state where each layer of coils 13 is stacked from the inside to the outside. The arrangement of each layer of coils 13 in this way to form a coil group 12 with an overlapping effect can greatly save space occupation, greatly improve the utilization rate of the use area of ​​the coils 13, thereby reducing the external dimensions of the equipment. At the same time, it can also ensure that each layer of coils 13 is evenly heated under the action of the electric heating rod 2, thereby ensuring that the low-temperature medium in the coil group 12 can effectively exchange heat with the heat exchange medium. The spiral structure of each layer of coils 13 can effectively reduce the thermal expansion and contraction deformation and stress deformation of the product caused by temperature differences. After the inlet and outlet ends of each layer of coils 13 are connected, the cryogenic medium inlet 9 and the cryogenic medium outlet 10 are formed respectively. In actual application, an adapter is selected, one side of which is connected to the inlet port of each layer of coils 13, and the other side is connected to the cryogenic medium inlet 9; similarly, one side of another adapter is connected to the outlet port of each layer of coils 13, and the other side is connected to the cryogenic medium outlet 10. The spiral structure can be a circular spiral or a rectangular spiral, which is not limited here.

[0040] In order to monitor the capacity of the heat exchange medium inside the heat exchanger shell 1 in real time, a liquid level gauge 3 is also provided on the heat exchanger shell 1. The probe of the liquid level gauge 3 extends into the interior of the heat exchanger shell 1 to obtain the liquid level of the heat exchange medium inside the heat exchanger shell 1 in real time through the liquid level gauge 3. When the heat exchange medium inside the heat exchanger shell 1 is too little, the regulating valve on the heat exchange medium inlet pipe 7 is opened to replenish the heat exchange medium inside the heat exchanger shell 1.

[0041] To ensure the safety of the equipment during operation, it also includes an automatic exhaust valve 4, one end of which is connected to the interior of the heat exchanger shell 1 through an inverted cone spiral condenser 6. The heat exchange medium will vaporize and the solution will evaporate due to heating. In special environments, the heat exchange medium solution will decrease over time. Since the inverted cone spiral condenser 6 is arranged on the top of the equipment and the inverted cone spiral condenser 6 is made of copper, the gas volatilized by the heat exchange medium passes through the inverted cone spiral condenser 6. Due to the long path and the high thermal conductivity of the copper material, it condenses into liquid and finally falls back into the interior of the heat exchanger shell 1, thereby avoiding the heat exchange medium in the heat exchanger shell 1 from being repeatedly added with heat exchange medium in a very short time.

[0042] In order to monitor the temperature value of the current state of the heat exchange medium inside the heat exchanger shell 1 in real time, a temperature transmitter 5 is also included on the heat exchanger shell 1, and the probe of the temperature transmitter 5 extends into the heat exchange medium inside the heat exchanger shell 1. For example: when the temperature transmitter 5 detects that the temperature of the heat exchange medium is low, the heating amount of the electric heating rod 2 can be adjusted to increase the temperature of the heat exchange medium. As for how to control the electric heating rod 2, the most common power adjustment method can be adopted, which will not be repeated here.

[0043] In this embodiment, the heat exchange medium is ethylene glycol solution, which is a solution obtained by mixing water and ethylene glycol in any proportion. Since the heat exchange medium is ethylene glycol solution with a low freezing point and no pollution, ethylene glycol and water can be mixed in any proportion to adjust the freezing point value, thereby matching different low-temperature media.

[0044] The working principle of the low temperature electric heating heat exchange device in this embodiment is as follows:

[0045] The heat exchange medium is selected to be an ethylene glycol solution that can be mixed in any proportion to adjust the freezing point of the solution. The low-temperature medium enters the coil group 12 and circulates in the coil group 12. The electric heating rod 2 heats the heat exchange medium, and the heat exchange medium transfers heat to the low-temperature medium through each layer of the coil 13, thereby achieving the effect of heating or vaporizing the low-temperature medium.

[0046] Example 2

[0047] On the basis of Example 1, in order to firmly install the coil group 12 inside the heat exchanger housing 1 to ensure the normal operation of the coil group 12, as shown in FIG. Figure 3 , Figure 4 as well as Figure 5 As shown, the heat exchanger shell 1 also includes a fixing plate 14 arranged in the heat exchanger shell 1, and a plurality of fixing holes 17 are opened on the fixing plate 14. The fixing holes 17 are arranged along the longitudinal direction and the transverse direction. The fixing holes 17 located in the same longitudinal direction correspond to the coils 13 of each layer respectively, and the fixing holes 17 located in the same transverse direction match the spiral shape of the coils 13 of the same layer respectively. In this embodiment, three layers of coils 13 are arranged and the spacing between two adjacent layers of coils 13 is equal. On the fixing plate 14, three horizontal rows of fixing holes 17 are provided along the longitudinal direction (i.e., the radial direction of the heat exchanger shell 1) (the horizontal row is the axial direction of the heat exchanger shell 1). The fixing holes 17 in each horizontal row correspond to each layer of coils 13. At the same time, since the spacing arrangement of the fixing holes 17 in each longitudinal row should meet the spiral shape of the coils 13, when installing the coils 13, it is only necessary to rotate the coils 13 so that it can be gradually screwed into each fixing hole 17 (located on the same horizontal row) to achieve a stable installation of the coils 13.

[0048] In order to achieve a lightweight design of the overall equipment and reduce stress concentration, a connecting plate 15 is provided on one side of the fixing plate 14 and the connecting plate 15 matches the inner wall of the heat exchanger shell 1 to ensure that the connecting plate 15 can be firmly welded to the inner wall of the heat exchanger shell 1. A plurality of hollow holes 16 are provided on the fixing plate 14. The plurality of hollow holes 16 can alleviate the stress concentration of the connecting plate 15 and the deformation damage of each layer of the coil 13 due to thermal expansion and contraction.

[0049] A plurality of support frames 11 are further provided at the bottom of the heat exchanger housing 1 , so that the entire device can be placed stably through each support frame 11 .

[0050] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that fall within the scope defined by the claims of the present invention fall within the protection scope of the present invention.

Claims

1. A low-temperature electric heating heat exchange device, comprising a heat exchanger shell, characterized in that: The heat exchanger shell has a heat exchange medium flowing therein, and also includes a coil group arranged inside the heat exchanger shell and a low-temperature medium flowing through the coil group, a hollow cavity is reserved inside the coil group, and a cryogenic medium inlet and a cryogenic medium outlet are arranged outside the heat exchanger shell and the two ends of the ports of the coil group are communicated with each other; and also includes an electric heating rod arranged on the heat exchanger shell, and the electric heating rod extends into and passes through the hollow cavity; The coil group includes multiple layers of coils, each layer of coils is configured as a spiral structure and each layer of coils is located on the same axis, and the inlet end and the outlet end of each layer of coils are connected to form the cryogenic medium inlet and the cryogenic medium outlet respectively; The heat exchanger also includes a fixing plate disposed in the heat exchanger shell, wherein the fixing plate is provided with a plurality of fixing holes, each of which is arranged in a longitudinal direction and a transverse direction, each of which is located in the same longitudinal direction and corresponds to each layer of coils, and each of which is located in the same transverse direction and matches the spiral shape of the coils in the same layer; A connecting plate is provided on one side of the fixing plate and the connecting plate matches the inner wall of the heat exchanger shell. The fixing plate is provided with a plurality of hollow holes and also includes an automatic exhaust valve. One end of the automatic exhaust valve is connected to the interior of the heat exchanger shell through an inverted cone spiral condenser.

2. The low-temperature electric heating heat exchange device according to claim 1, characterized in that: It also includes a liquid level meter arranged on the heat exchanger shell, and a probe of the liquid level meter extends into the interior of the heat exchanger shell.

3. The low-temperature electric heating heat exchange device according to claim 1, characterized in that: It also includes a temperature transmitter arranged on the heat exchanger shell, and a probe of the temperature transmitter extends into the heat exchange medium inside the heat exchanger shell.

4. The low-temperature electric heating heat exchange device according to claim 1, characterized in that: The heat exchanger shell is provided with a heat exchange medium inlet pipe and a heat exchange medium overflow pipe which are communicated with the interior thereof, and one end of the heat exchange medium overflow pipe extends into the top of the heat exchanger shell.

5. The low-temperature electric heating heat exchange device according to claim 1, characterized in that: The heat exchanger shell includes a cylindrical body and elliptical heads sealed and assembled at both ends of the cylindrical body. The coil group is placed on the central axis of the cylindrical body or below the central axis, and the electric heating rod is placed on the central axis of the coil group.

6. The low-temperature electric heating heat exchange device according to claim 1, characterized in that: The heat exchange medium is ethylene glycol solution.

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