A 2K return gas heater system with recoverable cold

Abstract

The utility model discloses a 2K back gas heater system of recoverable cold quantity, including circulating unit, cooling unit and normal temperature vacuum pump group, its characterized in that circulating unit includes normal temperature compressor, refrigerator cold box, negative pressure heat exchanger, superfluid helium tank and back gas heater, and the export of normal temperature compressor is connected with refrigerator cold box, negative pressure heat exchanger, superfluid helium tank and back gas heater in proper order, and from the export of back gas heater, normal temperature vacuum pump group and the import of normal temperature compressor are connected in proper order and form loop, and cooling unit includes water chiller, and the export of water chiller is connected with normal temperature vacuum pump group and back gas heater in proper order, and back gas heater connects the import of water chiller and forms loop, and wherein back gas heater includes gas pipe, multiple helium gas passages and gas collecting pipe, and gas pipe and gas collecting pipe are arranged at both ends of multiple helium gas passages, and the import of normal temperature compressor is connected to the export of gas collecting pipe, and low temperature helium flows through back gas heater liquid phase heat exchange.

Description

Technical Field

[0001] This utility model specifically relates to a 2K return gas heater system with recoverable cold energy, belonging to the technical field of 2K superfluid helium cryogenic systems. Background Technology

[0002] In 2K superfluid helium cryogenic systems, the pressure of 2K atmospheric-pressure liquid helium needs to be reduced to obtain even lower temperatures. This is typically achieved using an ambient-temperature depressurization pump system or a refrigerated compressor. Compared to refrigerated compressors, ambient-temperature depressurization pump systems offer advantages such as more stable operation, adaptability to varying loads, and improved control logic, and are commonly used in superconducting cryogenic system testing platforms. When the pressure of atmospheric-pressure liquid helium is reduced to approximately 31 mbar using an ambient-temperature depressurization pump system, 2K superfluid helium can be obtained. The extracted cryogenic helium gas needs to be rewarmed to room temperature before entering the ambient-temperature depressurization pump. Cryogenic helium rewarming is typically achieved using a 2K return gas heater.

[0003] Existing 2K return gas heaters typically use electric heating to reheat cryogenic helium to rewarm temperature. The main disadvantages include: 1. The cold energy in the cryogenic helium is wasted; 2. Electric heating requires additional power; 3. To ensure that the outlet temperature is at room temperature, the electric heating power needs to be precisely controlled, which is quite difficult.

[0004] Therefore, in order to address the shortcomings of the existing technology, a 2K return gas heater system with recoverable cold energy is proposed. Utility Model Content

[0005] The purpose of this invention is to provide a 2K return gas heater system capable of recovering cold energy in order to solve the problems mentioned in the background art.

[0006] This utility model achieves the above-mentioned objective through the following technical solution: a 2K return gas heater system capable of recovering cold energy, comprising a circulation unit, a cooling unit, and a room-temperature vacuum pump group, characterized in that:

[0007] The circulation unit includes a room temperature compressor, a refrigerator cold box, a negative pressure heat exchanger, an overflow helium tank, and a return gas heater. The outlet end of the room temperature compressor is sequentially connected to the refrigerator cold box, the negative pressure heat exchanger, the overflow helium tank, and the return gas heater. The outlet end of the return gas heater is sequentially connected to the room temperature vacuum pump group and the inlet end of the room temperature compressor to form a loop.

[0008] The cooling unit includes a chiller unit, the outlet end of which is sequentially connected to the ambient temperature vacuum pump unit and the return gas heater, and the return gas heater is connected to the inlet end of the chiller unit to form a loop.

[0009] The return gas heater includes a gas distribution pipe, multiple sets of helium channels and a gas collecting pipe. The gas distribution pipe and the gas collecting pipe are located at both ends of the multiple sets of helium channels. The outlet end of the gas collecting pipe is connected to the inlet end of the ambient temperature compressor. Low-temperature helium flows through the return gas heater for liquid phase heat exchange.

[0010] Furthermore, a throttling valve is also provided between the negative pressure heat exchanger and the superfluid helium tank for pressure reduction.

[0011] Furthermore, the refrigeration unit cold box includes a turbine expander and a heat exchanger.

[0012] Furthermore, a heating element is provided at one end of the return gas heater.

[0013] Furthermore, temperature sensors are provided below the heating assembly and at one end of the gas collecting pipe.

[0014] Furthermore, the return gas heater has an inlet and an outlet for cooling water at both ends.

[0015] The beneficial effects of this utility model are:

[0016] This invention uses cooling water from a normal temperature pump unit to heat the low-temperature helium flowing through a 2 K return gas heater, while simultaneously using the evaporated low-temperature helium to cool the heated cooling water. By employing liquid-phase heat exchange, both the power consumption of the chiller unit and the power consumption of the return gas heater are reduced. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the present invention;

[0018] Figure 2 This is a schematic diagram of the structure of the return gas heater of this utility model;

[0019] In the diagram: 1. Ambient temperature compressor; 2. Refrigeration unit cold box; 3. Negative pressure heat exchanger; 4. Throttling valve; 5. Overflow helium tank; 6. Return gas heater; 6.1. Gas distribution pipe; 6.2. Gas collection pipe; 6.3. Helium gas channel; 6.4. Temperature sensor; 7. Ambient temperature vacuum pump unit; 8. Chiller unit; 9. Heating components; 10. Cooling water. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Please see Figures 1-2 As shown, Figures 1-2 The diagram schematically illustrates a 2K return gas heater system capable of recovering cold energy according to the present invention.

[0022] A 2K return gas heater system capable of recovering cold energy, comprising a circulation unit, a cooling unit, and a room-temperature vacuum pump assembly 7, characterized in that:

[0023] The circulation unit includes a normal temperature compressor 1, a refrigerator cold box 2, a negative pressure heat exchanger 3, an overflow helium tank 5, and a return gas heater 6. The outlet end of the normal temperature compressor 1 is sequentially connected to the refrigerator cold box 2, the negative pressure heat exchanger 3, the overflow helium tank 5, and the return gas heater 6. The outlet end of the return gas heater 6 is sequentially connected to the normal temperature vacuum pump group 7 and the inlet end of the normal temperature compressor 1 to form a loop.

[0024] The cooling unit includes a chiller unit 8, and the outlet end of the chiller unit 8 is connected in sequence to a normal temperature vacuum pump unit 7 and a return gas heater 6. The return gas heater 6 is connected to the inlet end of the chiller unit 8 to form a loop.

[0025] The return gas heater 6 includes a gas distribution pipe, multiple helium channels, and a gas collecting pipe. The gas distribution pipe and the gas collecting pipe are located at both ends of the multiple helium channels. The outlet end of the gas collecting pipe is connected to the inlet end of the ambient temperature compressor. Low-temperature helium flows through the return gas heater for liquid-phase heat exchange.

[0026] In this process, helium gas flows through the tube side, and cooling water flows through the shell side, such as... Figure 2 As shown, the shaded area formed by the fine dots represents cooling water, a is the inlet and outlet of helium, and b is the inlet and outlet of cooling water.

[0027] Among them, the refrigeration unit cold box 2 is a 4.5K refrigeration unit cold box.

[0028] Among them, the return gas heater 6 is a 2K return gas heater.

[0029] Among these, the cooling water temperature is insufficient to heat the cryogenic helium gas.

[0030] The helium gas passage is made of stainless steel and is isolated and sealed from the cooling water passage by welding.

[0031] Furthermore, a throttling valve 4 is installed between the negative pressure heat exchanger 3 and the superfluid helium tank 5 to reduce pressure.

[0032] Furthermore, the refrigeration unit cold box 2 includes a turbine expander and a heat exchanger. (Not shown)

[0033] A heating element 9 is also provided at one end of the return gas heater 6.

[0034] The heating component 9 can be an electric heating rod or a heating wire.

[0035] Furthermore, temperature sensors 6.4 are installed below the heating component 9 and at one end of the gas collecting pipe 6.2.

[0036] The temperature sensor in the gas collecting pipe 6.2 is used to measure the outlet helium temperature to ensure that the outlet temperature is near room temperature.

[0037] The temperature sensor in the heating component 9 is used to ensure that the cooling water temperature is between 5 and 30 degrees Celsius.

[0038] Furthermore, the return gas heater 6 has an inlet and an outlet for cooling water 10 at both ends.

[0039] The working principle of this utility model:

[0040] Helium gas at room temperature and high pressure is compressed to 20 bara by room temperature compressor 1. It then passes through the turbine expander and heat exchanger in the cold box 2 of the refrigeration unit to form helium gas. The helium gas exchanges heat with the evaporating negative pressure 2 K helium gas in the superfluid helium tank in the negative pressure heat exchanger 3 and is further cooled to about 2.2 K. Then, the pressure is reduced from 3.5 bara to 31 bara by the throttling valve. 2 K negative pressure 2 K helium vapor and 2 K superfluid liquid helium are formed in the superfluid helium tank 4. The superfluid liquid helium is deposited at the bottom of the helium tank to replenish the liquid helium that evaporates due to heat in the helium tank. The negative pressure helium vapor is used to return to the negative pressure heat exchanger 3 to exchange heat with the incoming 4.5 K@3.5 bara.

[0041] The outlet temperature of the chilled water in the chiller unit 8 is about 10 degrees Celsius. After being cooled by the ambient temperature vacuum pump unit 7, the water temperature rises to 20-30 degrees Celsius. Then, it flows through the return gas heater and exchanges heat with the 2 K low temperature helium gas evaporated in the helium tank. After cooling down, it returns to the chiller unit 8.

[0042] The cryogenic helium enters from the cryogenic helium inlet below and is distributed to each helium channel through the gas distribution pipe. After exchanging heat with the cooling water on the surface of the stainless steel pipe, the cryogenic helium reaches room temperature and then enters the gas collecting pipe. Finally, it goes to the ambient temperature pump group through the gas collecting pipe. The cooling water enters the heat exchanger from the inlet below the return gas heater, flows through the helium pipeline and exchanges heat with the cryogenic helium, and then leaves the heating component 9 through the cooling water outlet pipe above.

[0043] The heating element 9 is used to heat the cooling water. When the cooling water temperature is too low (below 5 degrees Celsius), the heating element 9 can be activated. After being heated to 3.5 K, the water flows through the 2 K return gas heater 6 to exchange heat with the cooling water and continues to be heated to room temperature. Then, it is compressed by the ambient temperature pump group 2, and after the pressure reaches atmospheric pressure, it returns to the inlet of the ambient temperature compressor 1, forming a cycle.

[0044] The beneficial effects of this utility model are:

[0045] This invention uses cooling water from a normal temperature pump unit to heat the low-temperature helium flowing through a 2 K return gas heater, while simultaneously using the evaporated low-temperature helium to cool the heated cooling water. By employing liquid-phase heat exchange, both the power consumption of the chiller unit and the power consumption of the return gas heater are reduced.

[0046] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0047] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A 2K return gas heater system capable of recovering cold energy, comprising a circulation unit, a cooling unit, and a room-temperature vacuum pump assembly, characterized in that: The circulation unit includes a room temperature compressor, a refrigerator cold box, a negative pressure heat exchanger, an overflow helium tank, and a return gas heater. The outlet end of the room temperature compressor is sequentially connected to the refrigerator cold box, the negative pressure heat exchanger, the overflow helium tank, and the return gas heater. The outlet end of the return gas heater is sequentially connected to the room temperature vacuum pump group and the inlet end of the room temperature compressor to form a loop. The cooling unit includes a chiller unit, the outlet end of which is sequentially connected to the ambient temperature vacuum pump unit and the return gas heater, and the return gas heater is connected to the inlet end of the chiller unit to form a loop. The return gas heater includes a gas distribution pipe, multiple sets of helium channels and a gas collecting pipe. The gas distribution pipe and the gas collecting pipe are located at both ends of the multiple sets of helium channels. The outlet end of the gas collecting pipe is connected to the inlet end of the ambient temperature compressor. Low-temperature helium flows through the return gas heater for liquid phase heat exchange.

2. The 2K return gas heater system with recoverable cold energy as described in claim 1, characterized in that, A throttling valve is also provided between the negative pressure heat exchanger and the superfluid helium tank for pressure reduction.

3. A 2K return gas heater system for recovering cold energy as described in claim 2, characterized in that, The refrigeration unit cold box includes a turbine expander and a heat exchanger.

4. A 2K return gas heater system for recovering cold energy as described in claim 3, characterized in that, The return gas heater is also equipped with a heating component at one end.

5. A 2K return gas heater system for recovering cold energy as described in claim 4, characterized in that, Temperature sensors are installed below the heating assembly and at one end of the gas collecting pipe.

6. A 2K return gas heater system for recovering cold energy as described in claim 5, characterized in that, The return gas heater has an inlet and an outlet for cooling water at both ends.

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