Nitrogen making machine

Abstract

The utility model discloses a nitrogen making machine which comprises a heat exchanger, a nitrogen tower, a condensation evaporator, a first cooling capacity unit and a second cooling capacity unit, the nitrogen tower is communicated with the heat exchanger, air enters the nitrogen tower through the heat exchanger, the nitrogen tower prepares nitrogen and liquid air, and part of prepared nitrogen flows out through the heat exchanger; the condensation evaporator receives liquid air prepared by the nitrogen tower, converts the liquid air into waste nitrogen and discharges the waste nitrogen through the heat exchanger; the first cooling capacity unit provides first cooling capacity for the nitrogen making machine, comprises an expansion machine, is connected with the heat exchanger and is used for carrying out expansion cooling on waste nitrogen; the second cooling capacity unit provides second cooling capacity for the nitrogen making machine, comprises a liquid nitrogen tank, is connected with the nitrogen tower and is used for conveying liquid nitrogen to the nitrogen tower so as to cool the nitrogen making machine; the first cooling capacity unit and the second cooling capacity unit do not operate at the same time. Through combined use of the first cooling capacity unit and the second cooling capacity unit, stable operation of the nitrogen making machine can be guaranteed, and the nitrogen making efficiency is improved.

Description

TECHNICAL FIELD

[0001] The application relates to the field of nitrogen making machine equipment, in particular to a nitrogen making machine. BACKGROUND

[0002] At present, due to the market development of metal processing, electronics, photovoltaics and food industry, the small nitrogen making machine is widely used. Since the small nitrogen making machine device is small, the device has less loss of running cold, and the required refrigerating capacity is very small, so the device is favored by users. However, the cold quantity providing mode of the existing nitrogen making machine leads to poor stability of equipment operation, which affects the nitrogen making efficiency.

[0003] Therefore, there is an urgent need to develop a new nitrogen making machine which is stable in operation and has high nitrogen making efficiency. CONTENT OF THE INVENTION

[0004] The application mainly provides a nitrogen making machine which can improve the nitrogen making efficiency.

[0005] To solve the above technical problems, the technical scheme adopted by the application is as follows: a nitrogen making machine is provided, which comprises a heat exchanger, a nitrogen tower, a condensation evaporator, a first cold quantity unit and a second cold quantity unit; wherein the nitrogen tower is communicated with the heat exchanger, air enters the nitrogen tower through the heat exchanger, the nitrogen tower is used for preparing nitrogen gas and liquid air, and part of the prepared nitrogen gas flows out through the heat exchanger; the condensation evaporator receives the liquid air prepared by the nitrogen tower and converts the liquid air into dirty nitrogen which is discharged through the heat exchanger; the first cold quantity unit provides the first cold quantity for the nitrogen making machine, and comprises an expander which is connected with the heat exchanger and is used for expanding and cooling the dirty nitrogen; the second cold quantity unit provides the second cold quantity for the nitrogen making machine, and comprises a liquid nitrogen tank which is connected with the nitrogen tower and is used for transmitting liquid nitrogen to the nitrogen tower to cool the nitrogen making machine; and the first cold quantity unit and the second cold quantity unit do not operate at the same time.

[0006] The inlet of the liquefaction area of the condensation evaporator is connected with the upper end of the nitrogen tower, and is used for receiving the nitrogen gas prepared in the nitrogen tower; and the outlet of the liquefaction area of the condensation evaporator is connected with the upper end of the nitrogen tower, and is used for returning the liquefied nitrogen gas to the nitrogen tower.

[0007] The inlet of the condensation area of the condensation evaporator is connected with the lower end of the nitrogen tower, and is used for receiving the liquid air prepared in the nitrogen tower.

[0008] The nitrogen making machine further comprises a throttle valve, one end of the throttle valve is connected with the lower end of the nitrogen tower, and the other end of the throttle valve is connected with the condensation area of the condensation evaporator.

[0009] The first cold quantity unit further comprises an inlet-expander control valve, one end of the inlet-expander control valve is connected with the heat exchanger, and the other end of the inlet-expander control valve is connected with the inlet of the expander.

[0010] The first cold unit further comprises an outlet expander control valve, one end of which is connected to the heat exchanger, and the other end of which is connected to the outlet of the expander.

[0011] The first cold unit further comprises an expander bypass valve, which is connected in parallel to the expander, one end of which is connected to the inlet of the expander, and the other end of which is connected to the outlet of the expander.

[0012] The second cold unit further comprises a liquid nitrogen backflow valve, one end of which is connected to the outlet of the liquid nitrogen tank, and the other end of which is connected to the upper end of the nitrogen tower.

[0013] The nitrogen generator further comprises a backup unit, which is used to supply nitrogen gas directly from the liquid nitrogen tank when the first cold unit and the second cold unit fail, and comprises a gasifier connected to the outlet of the liquid nitrogen tank, which is used to gasify the liquid nitrogen to obtain nitrogen gas for use.

[0014] The backup unit further comprises a backup control valve connected to the gasifier, which is used to control the on-off of the nitrogen gas pipeline output from the gasifier.

[0015] The beneficial effects of the present application are: in the nitrogen generator of the present application, the first cold unit and the second cold unit are used in combination, and the first cold unit and the second cold unit do not operate at the same time, which can ensure the stable operation of the nitrogen generator and improve the nitrogen production efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the following embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor. Among them:

[0017] Figure 1 It is a structural schematic diagram of an embodiment of the nitrogen generator in the present application.

[0018] Marked with: 100 nitrogen generator; 1 heat exchanger; 2 nitrogen tower; 3 condenser evaporator; 31 liquefaction area; 32 condensation area; 4 first cold unit; 41 expander; 5 second cold unit; 51 liquid nitrogen tank; 6 backup unit; 61 gasifier; 7 throttle valve; 8 inlet expander control valve; 9 outlet expander control valve; 10 expander bypass valve; 11 liquid nitrogen backflow valve; 12 backup control valve; 13 cold box. DETAILED DESCRIPTION

[0019] In the following, the technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the protection scope of the present application.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application; the use of the terms "including," "comprising," "having" and variations thereof herein is meant to encompass the inclusion of the recited elements but not the exclusion of others.

[0021] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0022] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, or necessarily alternatives to other embodiments. It will be explicitly and implicitly appreciated by those of ordinary skill in the art that embodiments described herein can be combined with other embodiments.

[0023] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0024] Please refer to Figure 1The application provides a nitrogen generator 100, which comprises a heat exchanger 1, a nitrogen tower 2, a condensation evaporator 3, a first cold unit 4 and a second cold unit 5. The nitrogen tower 2 is communicated with the heat exchanger 1, air enters the nitrogen tower 2 through the heat exchanger 1, the nitrogen tower 2 prepares nitrogen and liquid air, and part of the prepared nitrogen flows out through the heat exchanger 1. The condensation evaporator 3 receives the liquid air prepared by the nitrogen tower 2 and is converted into dirty nitrogen which is discharged through the heat exchanger 1. The first cold unit 4 provides the first cold for the nitrogen generator 100, which comprises an expander 41 connected with the heat exchanger 1 and used for expanding and cooling the dirty nitrogen. The second cold unit 5 provides the second cold for the nitrogen generator 100, which comprises a liquid nitrogen tank 51 connected with the nitrogen tower 2 and used for transmitting liquid nitrogen to the nitrogen tower 2 to cool the nitrogen generator 100. The first cold unit 4 and the second cold unit 5 do not operate at the same time.

[0025] Specifically, the heat exchanger 1 can play the effects of air precooling, nitrogen reheating, energy recovery and utilization. Specifically, the nitrogen generator 100 usually takes air as raw material, and before entering the subsequent key processes such as compression and purification, the air needs to be pre-cooled. The heat exchanger 1 can use low-temperature process gas or other cooling medium to cool the air at normal temperature. At the same time, in the nitrogen generator 100, the nitrogen obtained through low-temperature separation and other processes usually has a low temperature. The heat exchanger 1 exchanges heat with the low-temperature nitrogen by using other high-temperature medium (such as heated air, steam, etc.), so that the temperature of the nitrogen is increased, and the temperature of the reheated nitrogen is closer to the normal temperature, which is convenient for safe and stable transportation to the user end. In addition, the gas temperature is different at different links in the nitrogen generator 100, and the heat exchanger 1 can realize heat recovery and redistribution. This energy recovery mode improves the energy utilization efficiency of the whole nitrogen generator 100, reduces the energy consumption, thereby reducing the nitrogen production cost and improving the economic benefit of the system.

[0026] In the nitrogen generator 100, the nitrogen tower 2 is a key equipment for realizing air separation and preparing high-purity nitrogen. The nitrogen tower 2 is communicated with the heat exchanger 1, air enters the nitrogen tower 2 through the heat exchanger 1, and the nitrogen tower 2 prepares nitrogen and liquid air, and part of the prepared nitrogen flows out through the heat exchanger 1.

[0027] In the nitrogen generator 100, the condensation evaporator 3 is a key heat exchange equipment in the nitrogen generator 100, and plays an indispensable role in the process of air separation and preparation of nitrogen. Its functions include realizing heat exchange, promoting gas-liquid conversion and ensuring efficient operation of the nitrogen generator 100. At the same time, the condensation evaporator 3 also receives the liquid air prepared by the nitrogen tower 2 and is converted into dirty nitrogen which is discharged through the heat exchanger 1.

[0028] In the nitrogen generator 100, the first cold unit 4 provides the first cold for the nitrogen generator 100, which includes an expander 41 connected with the heat exchanger 1, for expanding and cooling the dirty nitrogen. Specifically, the expander 41 mainly plays a role of refrigeration, which can be used to generate a low-temperature environment, and the expander 41 is an important refrigeration equipment in the nitrogen generator 100. It mainly works based on the principle of adiabatic expansion, and the gas does work outside after entering the expander 41, and the internal energy is reduced, and the temperature is lowered. In addition, the expander 41 can also be used to cool the circulating medium.

[0029] In the nitrogen generator 100, the second cold unit 5 provides the second cold for the nitrogen generator 100, which includes a liquid nitrogen tank 51 connected with the nitrogen column 2, for transmitting liquid nitrogen to the nitrogen column 2 to cool the nitrogen generator 100; the first cold unit 4 and the second cold unit 5 do not operate at the same time. Specifically, the temperature of the liquid nitrogen in the liquid nitrogen tank 51 is usually kept at about -196℃, which is very low, and when the liquid nitrogen tank 51 is connected with the nitrogen column 2 and transmits liquid nitrogen, it can cool the nitrogen generator 100.

[0030] The first cold unit 4 and the second cold unit 5 in the present application do not operate at the same time, when the first cold unit 4 fails, the second cold unit 5 can be started to cool the nitrogen generator 100, so as to realize the efficient operation of the nitrogen generator 100.

[0031] Please continue to refer to Figure 1 , the inlet of the liquefaction area 31 of the condensing evaporator 3 is connected with the upper end of the nitrogen column 2, for receiving the nitrogen prepared in the nitrogen column 2; specifically, part of the nitrogen prepared in the nitrogen column 2 flows out through the heat exchanger 1, and part of it enters the liquefaction area 31 of the condensing evaporator 3.

[0032] At the same time, the outlet of the liquefaction area 31 of the condensing evaporator 3 is connected with the upper end of the nitrogen column 2, for returning the liquefied nitrogen to the nitrogen column 2. Specifically, the reflux can improve the efficiency and capacity of the rectification of the nitrogen column 2, and the increase of the reflux liquid can improve the extraction rate of the extracted nitrogen.

[0033] Please continue to refer to Figure 1 , the inlet of the condensing area 32 of the condensing evaporator 3 is connected with the lower end of the nitrogen column 2, for receiving the liquid air prepared in the nitrogen column 2. Specifically, after the liquid air enters the condensing area 32 of the condensing evaporator 3, it can condense the nitrogen in the liquefaction area 31, so that the nitrogen is liquefied to form a reflux liquid and returns to the nitrogen column 2. Through the heat exchange of the evaporation of liquid oxygen in the liquid air and the condensation of nitrogen in the condensing evaporator 3, the additional energy consumption for realizing the gas-liquid conversion is avoided.

[0034] Please continue to refer to Figure 1The nitrogen generator 100 further comprises a throttle valve 7, one end of which is connected to the lower end of the nitrogen tower 2, and the other end of which is connected to the condensing area 32 of the condensing evaporator 3. Through the design of the throttle valve 7, the flow control of the pipeline between the lower end of the nitrogen tower 2 and the condensing area 32 of the condensing evaporator 3 can be realized, and the control of the liquid level in the nitrogen tower 2 can be realized.

[0035] Please continue to refer to Figure 1 The first cold unit 4 further comprises an inlet-expander control valve 8, one end of which is connected to the heat exchanger 1, and the other end of which is connected to the inlet of the expander 41. The inlet-expander control valve 8 is used to control the opening and closing of the pipeline through which the medium enters the expander 41 from the heat exchanger 1. When the inlet-expander control valve 8 is opened, the medium enters the expander 41 from the heat exchanger 1 through the inlet-expander control valve 8; when the inlet-expander control valve 8 is closed, the medium cannot enter the expander 41 from the heat exchanger 1 through the inlet-expander control valve 8.

[0036] Please continue to refer to Figure 1 The first cold unit 4 further comprises an outlet-expander control valve 9, one end of which is connected to the heat exchanger 1, and the other end of which is connected to the outlet of the expander 41. The outlet-expander control valve 9 is used to control the opening and closing of the pipeline through which the medium in the expander 41 enters the heat exchanger 1. When the outlet-expander control valve 9 is opened, the medium in the expander 41 enters the heat exchanger 1 through the outlet-expander control valve 9; when the outlet-expander control valve 9 is closed, the medium in the expander 41 cannot enter the heat exchanger 1 through the outlet-expander control valve 9.

[0037] Please continue to refer to Figure 1 The first cold unit 4 further comprises an expander bypass valve 10, which is connected in parallel with the expander 41, one end of which is connected to the inlet of the expander 41, and the other end of which is connected to the outlet of the expander 41. Specifically, when the inlet-expander control valve 8 and the outlet-expander control valve 9 are both closed, and the medium cannot enter the expander 41, the design of the expander bypass valve 10 facilitates the transmission of the medium. When the inlet-expander control valve 8 and the outlet-expander control valve 9 are not closed, the expander bypass valve 10 can play a role in shunting, thereby improving the operating efficiency of the nitrogen generator 100.

[0038] Please continue to refer to Figure 1 The nitrogen generator 100 further comprises a liquid nitrogen backflow valve 11, one end of which is connected to the outlet of the liquid nitrogen tank 51, and the other end of which is connected to the upper end of the nitrogen tower 2. Specifically, when the liquid nitrogen backflow valve 11 is closed, the liquid nitrogen in the liquid nitrogen tank 51 cannot flow into the nitrogen tower 2; when the liquid nitrogen backflow valve 11 is opened, the liquid nitrogen in the liquid nitrogen tank 51 can enter the nitrogen tower 2 at this time, and provide a second cold to the nitrogen generator 100. When the expander 41 fails, opening the liquid nitrogen backflow valve 11 can quickly and effectively provide a second cold to the nitrogen generator 100, and the control mode is simple and easy to operate.

[0039] Please continue to refer to Figure 1, the nitrogen generator 100 further comprises a backup unit 6, which is used to directly supply nitrogen gas from the liquid nitrogen tank 51 when the first cold unit 4 and the second cold unit 5 fail, and the backup unit 6 comprises a gasifier 61 connected with the outlet of the liquid nitrogen tank 51, which is used to gasify the liquid nitrogen to obtain nitrogen gas for use. Specifically, the design of the backup unit 6 ensures the smooth operation of the nitrogen generator 100, and the backup unit 6 is used to meet the use needs when the first cold unit 4 and the second cold unit 5 in the nitrogen generator 100 cannot normally work.

[0040] Please continue to refer to Figure 1 The backup unit 6 further comprises a backup control valve 12 connected with the gasifier 61, which is used to control the opening and closing of the nitrogen gas pipeline output from the gasifier 61. Specifically, the backup control valve 12 can control the transmission of the nitrogen gas in the gasifier 61 to the user, and when the backup unit 6 is not needed to be used, the backup control valve 12 is closed at this time.

[0041] The operation process of the nitrogen generator 100 in the present application is as follows: when starting, the expander bypass valve 10 is opened, the expander 41 is bypassed, the liquid nitrogen backflow valve 11 is opened, the liquid nitrogen is backflowed into the nitrogen tower 2, the nitrogen tower 2, the heat exchanger 1 and the condenser 3 and the corresponding cold box 13 are sequentially cooled, and then the liquid nitrogen backflow valve 11 is cut off when the temperature is reduced to a certain extent. The inlet control valve 8 and the outlet control valve 9 of the expander are opened, the expander 41 is started, and the expander 41 provides cold energy for the nitrogen generator 100. When the expander 41 fails and needs to be repaired, the liquid nitrogen backflow valve 11 is opened, the second cold unit 5 is started, that is, the liquid nitrogen backflow process is started, so that the nitrogen generator 100 can ensure continuous production. The nitrogen generator 100 is also provided with a liquid nitrogen tank 51 and a gasifier 61 as a backup unit 6. When the nitrogen generator 100 fails to produce nitrogen gas, the backup control valve 12 is opened, and the liquid nitrogen in the liquid nitrogen tank 51 is gasified to supply the user pipeline network.

[0042] The nitrogen generator 100 in the present application has the following advantages:

[0043] 1. The nitrogen generator 100 in the present application uses the combination of the first cold unit 4 and the second cold unit 5, and the configuration cost is reduced.

[0044] 2. Compared with the design of a single cold unit, the first cold unit 4 is used during normal operation, the consumption of liquid nitrogen is saved, and the normal operation cost is reduced. In the case of expander 41 failure, the second cold unit 5 is switched to the corresponding process, compared with directly using liquid nitrogen gasification to supply gas, the stability of nitrogen gas supply can be ensured, and the consumption of liquid nitrogen can be greatly reduced to reduce the operation cost under fault conditions.

[0045] 3. In the initial debugging of the device, gradually cool from hot state to near working temperature state. Compared with the system cooling by providing cold through the expander 41 alone, the use of the second cold unit 5 can greatly improve the cooling speed, save the debugging time and the related labor cost.

[0046] The above merely describes the embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A nitrogen generator, characterized in that, include: Heat exchanger; A nitrogen tower is connected to the heat exchanger. Air enters the nitrogen tower through the heat exchanger. The nitrogen tower prepares nitrogen gas and liquid air. A portion of the prepared nitrogen gas flows out through the heat exchanger. Condenser-evaporator; The liquid air prepared by the nitrogen tower is received and converted into waste nitrogen, which is then discharged through a heat exchanger. The first cooling unit provides a first cooling capacity to the nitrogen generator, including: An expander, connected to the heat exchanger, is used to expand and cool the waste nitrogen. The second cooling unit provides a second cooling capacity to the nitrogen generator, including: A liquid nitrogen tank, connected to the nitrogen tower, is used to transfer liquid nitrogen to the nitrogen tower to cool the nitrogen generator; The first cooling unit and the second cooling unit do not operate simultaneously.

2. The nitrogen generator according to claim 1, characterized in that, The inlet of the liquefaction zone of the condenser is connected to the upper end of the nitrogen tower for receiving the nitrogen gas prepared in the nitrogen tower; The outlet of the liquefaction zone of the condenser evaporator is connected to the upper end of the nitrogen tower, which is used to return the liquefied nitrogen gas to the nitrogen tower.

3. The nitrogen generator according to claim 1, characterized in that, The inlet of the condensation zone of the condenser is connected to the lower end of the nitrogen tower, and is used to receive the liquid air prepared in the nitrogen tower.

4. The nitrogen generator according to claim 1, characterized in that, Also includes: The throttling valve is connected at one end to the lower end of the nitrogen tower and at the other end to the condensation zone of the condenser-evaporator.

5. The nitrogen generator according to claim 1, characterized in that, The first cooling unit further includes: The expansion control valve is connected at one end to the heat exchanger and at the other end to the inlet of the expansion.

6. The nitrogen generator according to claim 1, characterized in that, The first cooling unit further includes: The expander control valve is connected at one end to the heat exchanger and at the other end to the outlet of the expander.

7. The nitrogen generator according to claim 1, characterized in that, The first cooling unit further includes: An expander bypass valve is connected in parallel with the expander, with one end connected to the inlet of the expander and the other end connected to the outlet of the expander.

8. The nitrogen generator according to claim 1, characterized in that, The second cooling unit also includes: The liquid nitrogen backflow valve is connected at one end to the outlet of the liquid nitrogen tank and at the other end to the top of the nitrogen tower.

9. The nitrogen generator according to claim 1, characterized in that, Also includes: The backup unit, in the event of a failure in the first and second cooling units, directly supplies nitrogen using a liquid nitrogen tank, including: The vaporizer, connected to the outlet of the liquid nitrogen tank, is used to vaporize liquid nitrogen to obtain nitrogen gas for use.

10. The nitrogen generator according to claim 9, characterized in that, The backup unit also includes: A backup control valve, connected to the vaporizer, is used to control the on / off state of the nitrogen pipeline output from the vaporizer.

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