An oxygen liquefaction device

Abstract

This application discloses an oxygen liquefaction device, belonging to the field of air separation technology. It can fully utilize the cold energy resources of liquid nitrogen and avoid oxygen release, thereby achieving energy savings. Furthermore, it stabilizes the flow rate within the nitrogen channel, making the energy exchange between liquid nitrogen and oxygen more stable, improving the overall stability of the liquefaction device and increasing oxygen liquefaction efficiency. The oxygen liquefaction device includes a liquid nitrogen conversion pipeline, a heat exchanger, and an oxygen conversion pipeline. The heat exchanger is used for heat exchange between liquid nitrogen and oxygen. The liquid nitrogen conversion pipeline includes a liquid nitrogen input pipeline and a nitrogen output pipeline. A liquid nitrogen power unit is installed on the liquid nitrogen input pipeline to pump liquid nitrogen from the liquid nitrogen storage tank to the heat exchanger and to regulate the flow rate of liquid nitrogen entering the heat exchanger. A nitrogen regulating valve is installed in the nitrogen output pipeline to regulate the flow rate of nitrogen guided out of the heat exchanger, thereby regulating the flow rate of liquid nitrogen entering the heat exchanger.

Description

Technical Field

[0001] This application belongs to the field of air separation technology, and particularly relates to an oxygen liquefaction device. Background Technology

[0002] Currently, the air separation backup system uses steam to vaporize nitrogen to meet short-term peak shaving and emergency supply needs. This process uses the thermal energy of steam to heat water, which then heats the low-temperature nitrogen in the coil to room temperature, converting it into nitrogen gas, which is then sent to the nitrogen pipeline network. This liquid nitrogen treatment method consumes both steam and wastes the cold energy resources of the low-temperature liquid nitrogen. Large-scale air separation oxygen production units are prone to oxygen release, resulting in wasted oxygen resources. How to fully recover the cold energy of liquid nitrogen vaporization, reduce oxygen release, and increase liquid oxygen production is an urgent problem to be solved. Summary of the Invention This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes an oxygen liquefaction device that can fully utilize the cold energy resources of liquid nitrogen, avoid oxygen release, thereby achieving energy saving, and making the flow rate in the nitrogen channel more stable, the energy exchange between liquid nitrogen and oxygen more stable, improving the stability of the entire liquefaction device, and increasing the oxygen liquefaction efficiency.

[0003] This application provides an oxygen liquefaction device, including: a liquid nitrogen conversion pipeline, a heat exchanger, and an oxygen conversion pipeline. The liquid nitrogen conversion pipeline is used to supply liquid nitrogen into the heat exchanger, and the oxygen conversion pipeline is used to supply oxygen into the heat exchanger. The heat exchanger is used to exchange heat between the liquid nitrogen and the oxygen entering the heat exchanger. The liquid nitrogen conversion pipeline includes a liquid nitrogen input pipeline and a nitrogen output pipeline. The liquid nitrogen input pipeline is used to supply liquid nitrogen into the heat exchanger, and the nitrogen output pipeline is used to guide nitrogen from the heat exchanger to a nitrogen pipeline network. A liquid nitrogen power unit is installed on the liquid nitrogen input pipeline. The liquid nitrogen power unit is used to pump the liquid nitrogen in the liquid nitrogen storage tank to the heat exchanger and to regulate the flow rate of liquid nitrogen entering the heat exchanger. A nitrogen regulating valve is installed in the nitrogen output pipeline. The nitrogen regulating valve is used to regulate the flow rate of nitrogen guided out of the heat exchanger.

[0004] In some embodiments, the inlet end of the liquid nitrogen input pipeline is connected to the liquid nitrogen storage tank, and the outlet end of the liquid nitrogen input pipeline is connected to the liquid nitrogen inlet end of the heat exchanger.

[0005] In some embodiments, the liquid nitrogen conversion pipeline further includes two liquid nitrogen pressurization pipelines, which are connected in parallel in the liquid nitrogen input pipeline; a liquid nitrogen pump is installed in the liquid nitrogen pressurization pipeline, which is used to pump liquid nitrogen from the liquid nitrogen storage tank to the heat exchanger.

[0006] In some embodiments, the liquid nitrogen conversion pipeline further includes a nitrogen temperature control pipeline, one end of which is connected to the intermediate nitrogen outlet of the heat exchanger, and the other end of which is connected to the inlet of the nitrogen regulating valve.

[0007] In some embodiments, a first shut-off valve is provided in the nitrogen temperature control pipeline, which is used to open or close the nitrogen temperature control pipeline.

[0008] In some embodiments, the oxygen conversion pipeline includes an oxygen input pipeline and a liquid oxygen output pipeline, wherein the oxygen input pipeline is used to supply oxygen into the heat exchanger, and the liquid oxygen output pipeline is used to guide liquid oxygen out of the heat exchanger.

[0009] In some embodiments, the oxygen input line is used to output oxygen from the oxygen network to a heat exchanger, and the liquid oxygen output line is used to guide liquid oxygen from the heat exchanger to a liquid oxygen storage tank.

[0010] In some embodiments, the oxygen input line is provided with an oxygen pressure regulating valve, which is used to regulate the pressure of the oxygen drawn from the heat exchanger.

[0011] In some embodiments, the liquid oxygen output pipeline is equipped with a flow meter and a flow regulating valve. The flow meter is used to measure the flow rate of liquid oxygen in the liquid oxygen output pipeline, and the flow regulating valve is used to regulate the flow rate of liquid oxygen in the liquid oxygen output pipeline.

[0012] The oxygen liquefaction device of this application includes a liquid nitrogen conversion pipeline, a heat exchanger, and an oxygen conversion pipeline. The liquid nitrogen conversion pipeline is used to supply liquid nitrogen into the heat exchanger, and the oxygen conversion pipeline is used to supply oxygen into the heat exchanger. The heat exchanger is used to exchange heat between the liquid nitrogen and oxygen entering the heat exchanger. Cryogenic liquid nitrogen is supplied to the heat exchanger through the liquid nitrogen conversion pipeline, and oxygen is simultaneously supplied to the heat exchanger through the oxygen conversion pipeline. The cryogenic liquid nitrogen and oxygen exchange heat within the heat exchanger; the oxygen transfers heat to the liquid nitrogen, and the cryogenic liquid nitrogen cools and condenses the oxygen. In this way, the liquid nitrogen heats up and converts into nitrogen gas, while the oxygen cools down and converts into liquid oxygen, thus realizing the oxygen liquefaction process. The oxygen liquefaction device of this application utilizes the cold energy of cryogenic liquid nitrogen for oxygen liquefaction, which can fully utilize the cold energy resource of liquid nitrogen and eliminates the need for additional steam treatment of liquid nitrogen, thereby saving energy. The liquefaction unit can liquefy and recover oxygen when there is oxygen release. It is especially efficient when there is a large amount of oxygen release, such as when the blast furnace is shut down for a short time or the converter smelting rhythm is uneven. This reduces oxygen release and waste of oxygen resources, thereby achieving the effect of saving energy.

[0013] In addition, the liquid nitrogen conversion pipeline includes a liquid nitrogen input pipeline and a nitrogen output pipeline. The liquid nitrogen input pipeline is used to supply liquid nitrogen into the heat exchanger, and the nitrogen output pipeline is used to guide nitrogen from the heat exchanger to the nitrogen pipeline network. A liquid nitrogen power unit is installed on the liquid nitrogen input pipeline to pump liquid nitrogen from the storage tank into the heat exchanger and to regulate the flow rate of liquid nitrogen entering the heat exchanger. A nitrogen regulating valve is installed in the nitrogen output pipeline to regulate the flow rate of nitrogen guided out of the heat exchanger, thereby regulating the flow rate of liquid nitrogen entering the heat exchanger. This allows for the use of the liquid nitrogen power unit to regulate the flow rate of liquid nitrogen in the liquid nitrogen input pipeline, and then the nitrogen regulating valve to regulate the flow rate of nitrogen in the nitrogen output pipeline. The combined use of these two flow regulation methods makes the flow rate in the nitrogen channel more stable, the energy exchange between liquid nitrogen and oxygen more stable, improves the stability of the entire liquefaction unit, and enhances the oxygen liquefaction efficiency. Attached Figure Description

[0014] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic overall diagram of an oxygen liquefaction device provided in an embodiment of this application; Figure 2 This is a schematic overall diagram of another oxygen liquefaction device provided in the embodiments of this application; Figure 3 This is a schematic overall diagram of another oxygen liquefaction device provided in the embodiments of this application; Among them, 10 is the liquid nitrogen conversion pipeline; 20 is the heat exchanger; 30 is the oxygen conversion pipeline; 101 is the liquid nitrogen input pipeline; 102 is the nitrogen output pipeline; 103 is the liquid nitrogen pressurization pipeline; 104 is the nitrogen temperature control pipeline; 301 is the oxygen input pipeline; 302 is the liquid oxygen output pipeline; 401 is the nitrogen pipeline network; 402 is the liquid nitrogen storage tank; 403 is the oxygen pipeline network; 404 is the liquid oxygen storage tank; 1011 is the liquid nitrogen power component; 1021 is the nitrogen regulating valve; 1031 is the liquid nitrogen pump; 1032 is the shut-off valve; 1033 is the check valve; 1034 is the reflux valve; 1041 is the temperature control valve; 3011 is the oxygen pressure regulating valve; 3012 is the pressure equalizing valve; 3021 is the flow meter; 3022 is the flow regulating valve; and 3023 is the quick-cut valve. Detailed Implementation

[0015] To better understand the technical solutions provided in the embodiments of this specification, the technical solutions of the embodiments of this specification will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.

[0016] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, the requirement defined by the phrase "comprising one..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element. The term "two or more" includes two or more cases.

[0017] Currently, the air separation backup system uses steam to vaporize nitrogen to meet short-term peak shaving and emergency supply needs. This process uses the thermal energy of steam to heat water, which then heats the low-temperature nitrogen in the coil to room temperature, converting it into nitrogen gas, which is then sent to the nitrogen pipeline network. This liquid nitrogen treatment method consumes both steam and wastes the cold energy resources of the low-temperature liquid nitrogen. Furthermore, although large-scale air separation oxygen production units have measures to reduce oxygen emissions, such as using buffer tanks, short-term shutdowns of blast furnaces and uneven production rhythms in converters still result in oxygen emissions, leading to wasted oxygen resources. Therefore, how to fully recover the cold energy from liquid nitrogen vaporization while reducing oxygen emissions and increasing liquid oxygen production is a problem that urgently needs to be solved.

[0018] In view of this, the present application provides an oxygen liquefaction device that can make full use of the cold energy resources of liquid nitrogen and avoid oxygen release, thereby achieving the effect of energy saving.

[0019] Figure 1 This is a schematic overall diagram of an oxygen liquefaction device provided in an embodiment of this application.

[0020] like Figure 1 As shown, the oxygen liquefaction device provided in this embodiment includes a liquid nitrogen conversion pipeline 10, a heat exchanger 20, and an oxygen conversion pipeline 30. The liquid nitrogen conversion pipeline 10 is used to supply liquid nitrogen into the heat exchanger 20, and the oxygen conversion pipeline 30 is used to input oxygen into the heat exchanger 20. The heat exchanger 20 is used to exchange heat between the liquid nitrogen and oxygen entering the heat exchanger 20. The heat exchanger 20 may have a nitrogen channel and an oxygen channel. The nitrogen channel is located in the liquid nitrogen conversion pipeline, and the oxygen channel is located in the oxygen conversion pipeline. Therefore, the liquid nitrogen conversion pipeline 10 can input cryogenic liquid nitrogen into the nitrogen channel within the heat exchanger 20, and the oxygen conversion pipeline 30 can input oxygen into the oxygen channel within the heat exchanger 20.

[0021] The heat exchanger 20 can be a plate heat exchanger. Multiple nitrogen channels and multiple oxygen channels are arranged alternately within the heat exchanger 20 to improve heat exchange efficiency. Liquid nitrogen enters the nitrogen channel, while oxygen enters the oxygen channel. Heat transfer occurs between the cryogenic liquid nitrogen and the high-temperature oxygen, causing the cryogenic liquid nitrogen to heat up and convert from liquid nitrogen to gaseous nitrogen. The high-temperature oxygen cools down and converts from gaseous oxygen to liquid oxygen, thus achieving oxygen liquefaction.

[0022] As can be seen, the oxygen liquefaction device of this application includes a liquid nitrogen conversion pipeline 10, a heat exchanger 20, and an oxygen conversion pipeline 30. The liquid nitrogen conversion pipeline 10 is used to supply liquid nitrogen into the heat exchanger 20, and the oxygen conversion pipeline 30 is used to supply oxygen into the heat exchanger 20. The heat exchanger 20 is used to exchange heat between the liquid nitrogen and the oxygen entering the heat exchanger 20. Cryogenic liquid nitrogen is supplied to the heat exchanger 20 through the liquid nitrogen conversion pipeline 10, and oxygen is simultaneously supplied to the heat exchanger 20 through the oxygen conversion pipeline 30. The cryogenic liquid nitrogen and oxygen exchange heat within the heat exchanger 20. The oxygen transfers heat to the liquid nitrogen, and the cryogenic liquid nitrogen cools and condenses the oxygen. In this way, the liquid nitrogen heats up and converts into nitrogen gas, while the oxygen cools down and converts into liquid oxygen, thereby realizing the oxygen liquefaction process.

[0023] The oxygen liquefaction device of this application utilizes the cold energy of cryogenic liquid nitrogen for oxygen liquefaction. This not only fully utilizes the cold energy resource of liquid nitrogen but also eliminates the need for additional steam treatment of the liquid nitrogen, thereby saving energy. The liquefaction device can liquefy and recover oxygen even when there is oxygen release, and its efficiency is particularly high during periods of short-term blast furnace shutdown or uneven converter smelting rhythm, which result in large release volumes. This reduces oxygen release and waste, thus achieving energy savings.

[0024] In addition, the oxygen liquefaction device of this application has a faster oxygen liquefaction rate, makes full use of the cooling energy of liquid nitrogen vaporization, and reduces oxygen dispersion, thus increasing liquid oxygen production and reducing the energy consumption of the air separation system.

[0025] In some implementations, such as Figure 1 As shown, the liquid nitrogen conversion pipeline 10 includes a liquid nitrogen inlet pipeline 101 and a nitrogen outlet pipeline 102. The liquid nitrogen inlet pipeline 101 is used to supply liquid nitrogen into the heat exchanger 20, and the nitrogen outlet pipeline 102 is used to guide nitrogen from the heat exchanger 20 to the nitrogen pipeline network 401. Specifically, the inlet end of the liquid nitrogen inlet pipeline 101 is connected to the liquid nitrogen storage tank 402, and the outlet end of the liquid nitrogen inlet pipeline 101 is connected to the liquid nitrogen inlet end of the heat exchanger 20. A liquid nitrogen power unit 1011 is provided on the liquid nitrogen inlet pipeline 101, which is used to pump the liquid nitrogen in the liquid nitrogen storage tank 402 into the heat exchanger 20.

[0026] In other words, one end of the liquid nitrogen input pipeline 101 is connected to the liquid nitrogen storage tank 402, and the other end is connected to the liquid nitrogen inlet of the heat exchanger 20. A liquid nitrogen power unit 1011 is installed in the liquid nitrogen input pipeline 101. When the liquid nitrogen power unit 1011 is working, it pumps the liquid nitrogen stored in the liquid nitrogen storage tank 402 into the liquid nitrogen channel of the heat exchanger 20. The liquid nitrogen power unit 1011 can be a liquid nitrogen pressurizer, such as an electric pump. It should be noted that the liquid nitrogen power unit 1011 can also regulate the flow rate of liquid nitrogen pumped from the liquid nitrogen storage tank 402 to the heat exchanger 20.

[0027] Figure 2 This is a schematic overall diagram of another oxygen liquefaction device provided in the embodiments of this application. Figure 2 As shown, the liquid nitrogen pressurizer can be a liquid nitrogen pump. The liquid nitrogen conversion line 10 can include a liquid nitrogen pressurization line 103.

[0028] Figure 3 This is a schematic overall diagram of another oxygen liquefaction device provided in the embodiments of this application. Figure 3 As shown, the liquid nitrogen conversion pipeline 10 also includes two liquid nitrogen pressurization pipelines 103, which are connected in parallel within the liquid nitrogen input pipeline 101. Each liquid nitrogen pressurization pipeline 103 is equipped with a liquid nitrogen pump 1031, which pumps liquid nitrogen from the liquid nitrogen storage tank 402 to the heat exchanger 20. The purpose of having two liquid nitrogen pressurization pipelines 103 is to allow the other pipeline to pump liquid nitrogen from the liquid nitrogen storage tank 402 to the heat exchanger 20 if one pipeline fails.

[0029] In addition, such as Figure 3 As shown, a shut-off valve 1032 and a check valve 1033 can be installed in each liquid nitrogen pressurization line 103. The shut-off valve 1032 can stop the flow of liquid nitrogen in the liquid nitrogen pressurization line 103. Therefore, it can also stop liquid nitrogen from entering the heat exchanger 20. The check valve 1033 can prevent liquid nitrogen from flowing back into the liquid nitrogen pump 1031, which could damage the liquid nitrogen pump 1031.

[0030] In some implementations, such as Figure 2 As shown, a return line can be installed after each liquid nitrogen pump 1031, and a return valve 1034 is installed on the return line. The return valve 1034 can regulate the pressure after the pump. The entire liquid nitrogen power unit 1011 uses the liquid nitrogen pump 1031 (variable frequency pump) and the return valve 1034 to more smoothly regulate the flow rate of liquid nitrogen entering the heat exchanger 20.

[0031] In some implementations, such as Figure 1As shown, a nitrogen regulating valve 1021 is provided in the nitrogen output pipeline 102. The nitrogen regulating valve 1021 is used to regulate the flow rate of nitrogen gas guided out from the heat exchanger 20, so as to regulate the flow rate of liquid nitrogen entering the heat exchanger 20. Since the liquid nitrogen input pipeline 101 is connected to the nitrogen output pipeline 102 through the nitrogen channel of the heat exchanger 20, the flow rate of liquid nitrogen in the liquid nitrogen input pipeline 101 can be correspondingly adjusted when the flow rate of nitrogen gas in the nitrogen output pipeline 102 is adjusted by the nitrogen regulating valve 1021.

[0032] If the nitrogen temperature in the nitrogen output pipeline 102 is too high, the nitrogen flow rate in the nitrogen output pipeline 102 can be increased by the nitrogen regulating valve 1021, and the flow rate of liquid nitrogen in the input pipeline 101 will also increase accordingly. If the nitrogen temperature in the nitrogen output pipeline 102 is too low, the nitrogen flow rate in the nitrogen output pipeline 102 can be decreased by the nitrogen regulating valve 1021, and the flow rate of liquid nitrogen in the liquid nitrogen input pipeline 101 will also decrease accordingly. Therefore, in this embodiment, the flow rate of liquid nitrogen in the liquid nitrogen input pipeline 101 can be adjusted using the liquid nitrogen power component 1011, and then the flow rate of nitrogen in the nitrogen output pipeline 102 can be adjusted using the nitrogen regulating valve 1021. In this way, even if the liquid nitrogen input pipeline 101 and the nitrogen output pipeline 102 are connected, the flow rate of liquid nitrogen in the liquid nitrogen input pipeline can be adjusted using the liquid nitrogen power component, and then the flow rate of nitrogen in the nitrogen output pipeline can be adjusted using the nitrogen regulating valve. The combined use of two flow regulation methods makes the flow rate in the nitrogen channel more stable, the energy exchange between liquid nitrogen and oxygen more stable, improves the stability of the entire liquefaction unit, and enhances the oxygen liquefaction efficiency.

[0033] like Figure 1 As shown, in some embodiments, the liquid nitrogen conversion pipeline 10 further includes a nitrogen temperature control pipeline 104. One end of the nitrogen temperature control pipeline 104 is connected to the intermediate nitrogen outlet of the heat exchanger 20, and the other end is connected to the inlet of the nitrogen regulating valve 1021. The nitrogen temperature control pipeline 104 is used to regulate the temperature of the nitrogen flowing through it.

[0034] Specifically, a temperature control valve 1041 can be installed on the nitrogen temperature control pipeline 104 to control the on / off state of the nitrogen temperature control pipeline 104. A tap is installed inside the heat exchanger 20, positioned in the middle of the nitrogen channel, and leading to a nitrogen outlet. Thus, one stream of nitrogen enters the nitrogen output pipeline 102, where it is fully heated to a higher temperature; another stream of nitrogen is drawn from the nitrogen outlet and enters the nitrogen temperature control pipeline 104, where it is not fully heated to a lower temperature. The two streams of nitrogen merge at their ends before entering the nitrogen network 401. If the nitrogen temperature entering the nitrogen network 401 is too high (a temperature measuring point can be set on the nitrogen network 401 to monitor the temperature of the nitrogen on the pipeline, that is, to monitor the temperature of the nitrogen after merging, and to control the opening and closing of the nitrogen temperature control pipeline 104 according to the monitored temperature), the temperature control valve 1041 can be opened to divert a portion of the low-temperature nitrogen into the nitrogen network 401, thereby reducing the final merging nitrogen temperature.

[0035] like Figure 1 As shown, in some embodiments, the oxygen conversion pipeline 30 includes an oxygen inlet pipeline 301 and a liquid oxygen outlet pipeline 302. The oxygen inlet pipeline 301 is used to supply oxygen into the heat exchanger 20, and the liquid oxygen outlet pipeline 302 is used to guide liquid oxygen out of the heat exchanger 20. One end of the oxygen inlet pipeline 301 is connected to the oxygen pipeline network 403, and the other end of the oxygen inlet pipeline 301 is connected to the inlet of the oxygen channel of the heat exchanger 20. In this way, oxygen in the oxygen pipeline network 403 can enter the oxygen channel of the heat exchanger 20 through the oxygen inlet pipeline 301, and exchange heat with cryogenic liquid nitrogen in the nitrogen channel of the heat exchanger 20.

[0036] Oxygen inlet pipe 301 is used to output oxygen from oxygen network 403 to heat exchanger 20, and liquid oxygen outlet pipe 302 is used to guide liquid oxygen from heat exchanger 20 to liquid oxygen storage tank 404. Figure 1 As shown, one end of the liquid oxygen output pipeline 302 is connected to the outlet of the oxygen channel of the heat exchanger 20, and the other end of the liquid oxygen output pipeline 302 is connected to the liquid oxygen storage tank 404. In this way, the liquid oxygen generated after heat exchange can enter the liquid oxygen storage tank 404 for storage through the liquid oxygen output pipeline 302.

[0037] like Figure 1As shown, an oxygen pressure regulating valve 3011 is installed in the oxygen input pipeline 301. The oxygen pressure regulating valve 3011 is used to regulate the oxygen pressure in the heat exchanger 20. If the oxygen pressure in the oxygen input pipeline 301 is detected to be too high (a pressure measuring point can be installed next to the oxygen pressure regulating valve 3011 to monitor the oxygen pressure in the oxygen input pipeline 301, and then the on / off state of the oxygen pressure regulating valve 3011 can be controlled based on the monitored oxygen pressure), the oxygen pressure can be reduced through the oxygen pressure regulating valve 3011, thereby allowing the heat exchanger to operate at a suitable pressure. If the oxygen pressure in the oxygen input pipeline 301 is detected to be too low, the oxygen pressure can be increased through the oxygen pressure regulating valve 3011 to improve oxygen liquefaction efficiency. A shut-off valve can also be installed at the outlet of the oxygen pipeline network 403. If it is not necessary to stop the production of liquid oxygen, the oxygen input pipeline 301 can be directly shut off through the shut-off valve.

[0038] In some implementations, such as Figure 1 As shown, the liquid oxygen output pipeline 302 is equipped with a flow meter 3021 and a flow regulating valve 3022. The flow meter 3021 measures the flow rate of liquid oxygen in the liquid oxygen output pipeline 302, and the flow regulating valve 3022 regulates the flow rate of liquid oxygen in the liquid oxygen output pipeline 302, which is to say, regulates the flow rate of liquid oxygen produced by the liquefaction device. When the flow rate of liquid oxygen in the liquid oxygen output pipeline 302 is regulated by the flow regulating valve 3022, since the liquid oxygen output pipeline 302 and the oxygen input pipeline 301 are connected, the flow rate of oxygen in the oxygen input pipeline 301 can also be regulated accordingly. In other words, the flow rates of oxygen and liquid oxygen in the entire oxygen conversion pipeline 30 can be regulated by a single flow regulating valve 3022, thereby controlling the entire oxygen liquefaction process, improving the oxygen liquefaction regulation efficiency, and ultimately improving the overall oxygen liquefaction efficiency.

[0039] In some implementations, such as Figure 1 As shown, an equalizing valve 3012 is connected in parallel across the oxygen pressure regulating valve 3011. Directly operating the oxygen pressure regulating valve 3011 in the oxygen inlet pipeline 301 may result in a large pressure difference across the two sides, causing excessively high oxygen flow and potentially burning out the valve. Therefore, before opening the oxygen pressure regulating valve 3011, the equalizing valve 3012 should be opened first to equalize the pressure across the oxygen pressure regulating valve 3011, and then the oxygen pressure regulating valve 3011 should be opened to prevent excessively high oxygen flow.

[0040] In addition, such as Figure 1 A quick-cut valve 3023 can also be installed at the end of the liquid oxygen output pipeline 302 near the oxygen storage tank 404. When a problem occurs in the liquefaction unit, the liquid oxygen output pipeline 302 can be shut off by the quick-cut valve 3023 to prevent the accident from escalating.

[0041] It should be noted that the embodiments of this application can also include a controller, which can be used to control electrical components such as nitrogen regulating valves and oxygen pressure regulating valves. For example, the flow meter 3021 of the liquid oxygen output pipeline 302 can periodically send current flow data to the controller. Then, based on the relationship between the current flow data and preset flow data, the controller sends a drive signal to the driver of the flow regulating valve 3022, driving the flow regulating valve 3022 to operate and regulate the flow rate of liquid oxygen in the liquid oxygen output pipeline 302.

[0042] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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 application.

[0043] Although preferred embodiments have been described in this specification, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this specification.

[0044] Obviously, those skilled in the art can make various modifications and variations to this specification without departing from its spirit and scope. Therefore, if such modifications and variations fall within the scope of the claims and their equivalents, this specification is also intended to include such modifications and variations.

Claims

1. An oxygen liquefaction device, characterized in that, include: The liquid nitrogen conversion pipeline, heat exchanger, and oxygen conversion pipeline are provided. The liquid nitrogen conversion pipeline is used to supply liquid nitrogen into the heat exchanger, and the oxygen conversion pipeline is used to supply oxygen into the heat exchanger. The heat exchanger is used to exchange heat between the liquid nitrogen and the oxygen entering the heat exchanger. The liquid nitrogen conversion pipeline includes a liquid nitrogen input pipeline and a nitrogen output pipeline. The liquid nitrogen input pipeline is used to deliver liquid nitrogen into the heat exchanger, and the nitrogen output pipeline is used to guide nitrogen from the heat exchanger to the nitrogen pipeline network. A liquid nitrogen power unit is installed on the liquid nitrogen input pipeline. The liquid nitrogen power unit is used to pump liquid nitrogen from the liquid nitrogen storage tank into the heat exchanger and to regulate the flow rate of liquid nitrogen entering the heat exchanger. A nitrogen regulating valve is installed in the nitrogen output pipeline. The nitrogen regulating valve is used to regulate the flow rate of nitrogen guided out of the heat exchanger.

2. The oxygen liquefaction device according to claim 1, characterized in that, The inlet end of the liquid nitrogen input pipeline is connected to the liquid nitrogen storage tank, and the outlet end of the liquid nitrogen input pipeline is connected to the liquid nitrogen inlet end of the heat exchanger.

3. The oxygen liquefaction device according to claim 2, characterized in that, The liquid nitrogen conversion pipeline also includes two liquid nitrogen pressurization pipelines, which are connected in parallel in the liquid nitrogen input pipeline; a liquid nitrogen pump is installed in the liquid nitrogen pressurization pipeline, which is used to pump liquid nitrogen from the liquid nitrogen storage tank to the heat exchanger.

4. The oxygen liquefaction device according to claim 1, characterized in that, The liquid nitrogen conversion pipeline also includes a nitrogen temperature control pipeline, one end of which is connected to the intermediate nitrogen outlet of the heat exchanger, and the other end of which is connected to the inlet of the nitrogen regulating valve.

5. The oxygen liquefaction device according to claim 4, characterized in that, The nitrogen temperature control pipeline is equipped with a first shut-off valve, which is used to open or close the nitrogen temperature control pipeline.

6. The oxygen liquefaction device according to claim 1, characterized in that, The oxygen conversion pipeline includes an oxygen input pipeline and a liquid oxygen output pipeline. The oxygen input pipeline is used to supply oxygen into the heat exchanger, and the liquid oxygen output pipeline is used to guide liquid oxygen out of the heat exchanger.

7. The oxygen liquefaction apparatus according to claim 6, characterized in that, The oxygen input pipeline is used to output oxygen from the oxygen network to the heat exchanger, and the liquid oxygen output pipeline is used to guide liquid oxygen from the heat exchanger to the liquid oxygen storage tank.

8. The oxygen liquefaction apparatus according to claim 7, characterized in that, The oxygen input pipeline is equipped with an oxygen pressure regulating valve, which is used to regulate the pressure of the oxygen input into the heat exchanger.

9. The oxygen liquefaction apparatus according to claim 8, characterized in that, The liquid oxygen output pipeline is equipped with a flow meter and a flow regulating valve. The flow meter is used to measure the flow rate of liquid oxygen in the liquid oxygen output pipeline, and the flow regulating valve is used to regulate the flow rate of liquid oxygen in the liquid oxygen output pipeline.

10. The oxygen liquefaction apparatus according to claim 8, characterized in that, The oxygen pressure regulating valve is provided with a pressure equalization valve in parallel at both ends. The pressure equalization valve is used to regulate the pressure at both ends of the oxygen pressure regulating valve so as to keep the pressure at both ends of the oxygen pressure regulating valve balanced.

Images