Liquid nitrogen cooling capacity recycling device for air compression system

Abstract

The utility model relates to a liquid nitrogen cold energy recycling device for an air compression system, which comprises a liquid nitrogen tank, a liquid nitrogen vaporizer and a heat exchanger, the air compression system comprises a freezing dryer, a cold source inlet of the heat exchanger is communicated with a liquid nitrogen outlet of the liquid nitrogen tank, and a cold source outlet of the heat exchanger is communicated with a liquid nitrogen inlet of the liquid nitrogen vaporizer. A heat source inlet of the heat exchanger is communicated with a cooling water outlet of the refrigeration dryer, and a heat source outlet of the heat exchanger is communicated with a cooling water inlet of the refrigeration dryer. According to the utility model, the heat exchanger is arranged to cool the circulating cooling water by using the cooling capacity of the liquid nitrogen, and the cooled cooling water is supplied to the freezing dryer of the air compression system, so that the energy consumption of the air compression system is reduced, the cooling capacity of the liquid nitrogen is fully recycled, and the waste of resources is reduced.

Description

Technical Field

[0001] The utility model relates to an energy recovery and utilization device, in particular to a liquid nitrogen cold recovery and utilization device for an air compression system. Background Art

[0002] At present, nitrogen and compressed air are widely used in various production links of factories. The nitrogen used in factories is generally produced by nitrogen production system or liquid nitrogen system. When nitrogen is produced by nitrogen production system, it is necessary to produce compressed air through air compressor system, and then input compressed air into nitrogen production system to produce nitrogen. Compressed air is directly produced by air compressor system.

[0003] It can be seen that whether it is using a nitrogen production system to produce nitrogen or compressed air, it is inseparable from the air compression system. The air compression system is generally composed of an air compressor, a cold dryer, and a suction dryer. After the air is compressed by the compressor, a large amount of compression heat will be generated, so a cold dryer is required for refrigeration and dehumidification, which requires a large amount of cold capacity; if the process has high requirements for the humidity of the compressed air, a suction dryer is required to further absorb the moisture in the compressed air, which also requires more cold capacity, resulting in the problem of high energy consumption of the air compression system. At present, the energy consumption of the air compression system accounts for about 10% of the total electricity consumption in the country. Furthermore, when using a liquid nitrogen system to produce nitrogen, the temperature of liquid nitrogen is generally -196°C. When it is vaporized through a vaporizer, a large amount of cold capacity will be released. However, this ultra-low temperature cold capacity has not been fully utilized at present, which causes a huge waste of resources. Utility Model Content

[0004] Based on this, it is necessary to address the technical problem that the current air compression system has high energy consumption, the liquid nitrogen cooling capacity is not fully utilized when the liquid nitrogen system produces nitrogen, resulting in a huge waste of resources. The utility model provides a liquid nitrogen cooling capacity recovery and utilization device for an air compression system.

[0005] The utility model proposes a liquid nitrogen cold capacity recovery and utilization device for an air compression system, which comprises a liquid nitrogen tank, a liquid nitrogen vaporizer and a cold dryer, and further comprises a heat exchanger, wherein a cold source inlet of the heat exchanger is communicated with a liquid nitrogen outlet of the liquid nitrogen tank, and the cold source outlet thereof is communicated with a liquid nitrogen inlet of the liquid nitrogen vaporizer, and a heat source inlet of the heat exchanger is communicated with a cooling water outlet of the cold dryer, and the heat source outlet thereof is communicated with a cooling water inlet of the cold dryer.

[0006] The utility model arranges a heat exchanger to cool the circulating cooling water by utilizing the cold capacity of liquid nitrogen, and provides the cooled circulating cooling water to a cold dryer of an air compression system, which not only reduces the energy consumption of the air compression system, but also fully recycles and utilizes the cold capacity of the liquid nitrogen, thereby reducing the waste of the cold capacity of the liquid nitrogen; at the same time, the liquid nitrogen absorbs the heat of the circulating cooling water in the heat exchanger and vaporizes, thereby avoiding incomplete vaporization of the liquid nitrogen passing through the heat exchanger, and further vaporizing the liquid nitrogen through a liquid nitrogen vaporizer, thereby ensuring the effective nitrogen production and the normal supply of nitrogen.

[0007] As a further improvement of the above solution of the utility model, the air compression system also includes a desiccant, and the heat source inlet of the heat exchanger is connected to the cooling water outlet of the desiccant, and the heat source outlet is connected to the cooling water inlet of the desiccant. The circulating cooling water cooled by heat exchange with liquid nitrogen is also provided to the desiccant of the air compression system, further reducing the energy consumption of the air compression system.

[0008] As a further improvement of the above solution of the utility model, the heat exchanger adopts a shell and tube heat exchanger or a plate heat exchanger, which can fully utilize the cooling capacity of liquid nitrogen and reduce the waste of cooling capacity of liquid nitrogen.

[0009] As a further improvement of the above solution of the utility model, the liquid nitrogen cold recovery and utilization device for the air compression system also includes a pipeline 1, the two ends of which are respectively connected to the liquid nitrogen outlet of the liquid nitrogen tank and the cold source inlet of the heat exchanger, and an insulation layer 1 is arranged outside the pipeline 1. By providing the insulation layer 1, the loss of liquid nitrogen cold can be avoided.

[0010] As a further improvement of the above solution of the utility model, a valve 1 is arranged on the pipeline 1. By arranging the valve 1 on the pipeline 1, the flow rate of the liquid nitrogen can be adjusted.

[0011] As a further improvement of the above solution of the utility model, the liquid nitrogen cooling capacity recovery and utilization device for the air compression system further includes a second pipeline, the two ends of which are respectively connected to the cold source outlet of the heat exchanger and the liquid nitrogen inlet of the liquid nitrogen vaporizer, and a second insulation layer is arranged outside the second pipeline. By providing the second insulation layer, the loss of nitrogen or liquid nitrogen cooling capacity can be avoided.

[0012] As a further improvement of the above solution of the utility model, a valve 2 is provided on the pipeline 2. By providing the valve 2 on the pipeline 2, the flow rate of nitrogen or liquid nitrogen can be adjusted.

[0013] As a further improvement of the above scheme of the utility model, the liquid nitrogen cooling capacity recovery and utilization device for the air compression system also includes pipeline 3, pipeline 4 and circulating pump 1, the two ends of pipeline 3 are respectively connected to the heat source inlet of the heat exchanger and the cooling water outlet of the cold dryer, the two ends of pipeline 4 are respectively connected to the heat source outlet of the heat exchanger and the cooling water inlet of the cold dryer, and an insulation layer 3 is arranged outside pipeline 4, and the inlet and outlet of circulating pump 1 are connected to the pipeline of pipeline 4. By providing insulation layer 3, the loss of cooling water cooling capacity can be avoided.

[0014] As a further improvement of the above solution of the utility model, valves 3 and 4 are respectively provided on pipeline 3 and pipeline 4. By providing valves 3 and 4, the flow rate of cooling water can be adjusted.

[0015] As a further improvement of the above scheme of the utility model, the liquid nitrogen cooling capacity recovery and utilization device for the air compression system also includes pipeline 5, pipeline 6 and circulating pump 2. The two ends of pipeline 5 are respectively connected to the heat source inlet of the heat exchanger and the cooling water outlet of the desiccant machine. The two ends of pipeline 6 are respectively connected to the heat source outlet of the heat exchanger and the cooling water inlet of the desiccant machine, and a heat preservation layer 4 is arranged outside pipeline 6. The inlet and outlet of circulating pump 2 are connected to the pipeline of pipeline 6. Valves 5 and 6 are respectively arranged on pipeline 5 and pipeline 6. By arranging the heat preservation layer 4, the loss of cooling water cooling capacity can be avoided; by arranging the valves 5 and 6, the flow rate of cooling water can be adjusted.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] The utility model arranges a heat exchanger to cool the circulating cooling water by utilizing the cold capacity of liquid nitrogen, and provides the cooled cooling water to a cold dryer of an air compression system, which not only reduces the energy consumption of the air compression system, but also fully recycles and utilizes the cold capacity of liquid nitrogen, thereby reducing the waste of liquid nitrogen cold capacity; at the same time, the liquid nitrogen absorbs the heat of the circulating cooling water in the heat exchanger and vaporizes, thereby avoiding incomplete vaporization of the liquid nitrogen passing through the heat exchanger, and further vaporizing the liquid nitrogen through a liquid nitrogen vaporizer, thereby ensuring the effective nitrogen production and the normal supply of nitrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of a liquid nitrogen cooling capacity recovery and utilization device for an air compression system proposed in an embodiment of the utility model.

[0019] Figure numerals: 1. liquid nitrogen tank; 2. liquid nitrogen vaporizer; 3. cold dryer; 4. heat exchanger; 5. adsorption dryer; 6. pipeline one; 7. valve one; 8. pipeline two; 9. valve two; 10. pipeline three; 11. pipeline four; 12. circulation pump one; 13. valve three; 14. valve four; 15. pipeline five; 16. pipeline six; 17. circulation pump two; 18. valve five; 19. valve six; 20. buffer tank; 21. air compressor; 22. pressure regulating tank; 23. dry tank. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] This embodiment aims to solve the technical problem that the energy consumption of the current air compression system is high, the liquid nitrogen cooling capacity is not fully utilized when the liquid nitrogen system produces nitrogen, resulting in a huge waste of resources, and provides a liquid nitrogen cooling capacity recovery and utilization device for the air compression system. Figure 1 The liquid nitrogen cooling capacity recovery and utilization device for the air compression system of this embodiment includes a liquid nitrogen tank 1, a liquid nitrogen vaporizer 2 and a heat exchanger 4, and may also include pipeline 1 6, pipeline 2 8, pipeline 3 10, pipeline 4 11, pipeline 5 15, pipeline 6 16, circulating pump 1 12 and circulating pump 2 17.

[0022] The liquid nitrogen cold recovery and utilization device for air compression system of the present embodiment is used for air compression system, and circulating cooling water is provided for air compression system by recycling liquid nitrogen cold, so as to reduce the energy consumption of air compression system. The air compression system mainly includes air compressor 21, pressure stabilizing tank 22, cold dryer 3, adsorption dryer 5 and dry tank 23. The output end of air compressor 21 is connected with the input end of pressure stabilizing tank 22 through pipe fitting, the output end of pressure stabilizing tank 22 is connected with the input end of cold dryer 3 through pipe fitting, the output end of cold dryer 3 is connected with the input end of adsorption dryer 5 through pipe fitting, the output end of adsorption dryer 5 is connected with dry tank 23 through pipe fitting, the compressed air generated by air compressor 21 is input into pressure stabilizing tank 22 for pressure stabilization, and then enters into cold dryer 3, cold dryer 3 dehumidifies compressed air and then delivers compressed air to adsorption dryer 5, adsorption dryer 5 further dehumidifies compressed air, and completely dry compressed air is delivered to dry tank 23 for buffering, and the output end of dry tank 23 is connected with gas using end through pipe fitting. The air compressor 21, the pressure-stabilizing tank 22, the cold dryer 3, the desiccant 5 and the dry tank 23 of this embodiment are all devices known in the prior art, and their working principles are known, which will not be described in detail here.

[0023] Liquid nitrogen is stored in the liquid nitrogen tank 1. In this embodiment, the liquid nitrogen tank 1 adopts the existing technology, and its working principle is clear, which will not be described in detail here. Its main function is to store and transport liquid nitrogen. The liquid nitrogen tank 1 adopts high vacuum insulation technology to effectively reduce heat transfer, thereby maintaining the low temperature state of the liquid nitrogen in the tank to ensure the safety, stability and effectiveness of the liquid nitrogen during use.

[0024] The function of the heat exchanger 4 is to realize the transfer of heat from the heat source to the source, and improve the energy utilization rate. In this embodiment, the heat exchanger 4 adopts the partition wall heat exchanger 4 of the prior art, such as the shell and tube heat exchanger 4 or the plate heat exchanger 4, and its working principle is clear, and it is not repeated here. It has a heat source inlet, a heat source outlet, a cold source inlet and a cold source outlet. The heat source inlet of the heat exchanger 4 is connected to the cooling water outlet of the cold dryer 3 and the cooling water outlet of the absorption dryer 5 through the pipeline three 10 and the pipeline five 15, respectively. The heat source outlet of the heat exchanger 4 is connected to the cooling water inlet of the cold dryer 3 and the cooling water inlet of the absorption dryer 5 through the pipeline four 11 and the pipeline six 16, respectively, and the circulating pump one 12 and the circulating pump two 17 are connected to the pipelines of the pipeline four 11 and the pipeline six 16, respectively. In order to facilitate the adjustment of the flow rate and flow of the cooling water, the pipeline three 10, the pipeline four 11, the pipeline five 15, and the pipeline six 16 are respectively connected with the valve three 13, the valve four 14, the valve five 18, and the valve six 19. The cold source inlet of the heat exchanger 4 is connected to the liquid nitrogen outlet of the liquid nitrogen tank 1 through a pipe 1 6. To facilitate the adjustment of the flow rate and speed of the liquid nitrogen, a valve 1 7 is provided on the pipe 1 6. To avoid the loss of cold, in this embodiment, the pipe 1 6, the pipe 4 11, and the pipe 6 16 can be provided with an insulation layer 1, an insulation layer 3, and an insulation layer 4, respectively.

[0025] In this embodiment, through the above structural arrangement, liquid nitrogen is used as the cold source of the heat exchanger 4, and the cooling water return water of the cold dryer 3 and the adsorption dryer 5 is used as the heat source. The cooling water return water absorbs the coldness of the liquid nitrogen in the heat exchanger 4 and then cools down, while the liquid nitrogen absorbs heat and vaporizes to form nitrogen gas, and flows back to the cold dryer 3 and the adsorption dryer 5 respectively under the action of the circulating pump 1 12 and the circulating pump 2 17. In this way, the circulation effectively provides cooling water for the cold dryer 3 and the adsorption dryer 5 of the air compression system, thereby effectively utilizing the coldness of the liquid nitrogen and reducing the energy consumption of the air compression system.

[0026] At the same time, in order to prevent the situation that the liquid nitrogen cannot be completely recovered by the heat exchanger 4 after passing through the heat exchanger 4, so that the nitrogen output by the heat exchanger 4 is a gas-liquid mixture, resulting in the workshop being unable to use gas, the present embodiment is also provided with a liquid nitrogen vaporizer 2, and the cold source outlet of the heat exchanger 4 is connected to the liquid nitrogen inlet of the liquid nitrogen vaporizer 2 through a pipe 2 8. In order to facilitate the adjustment of the flow rate and speed of the liquid nitrogen, a valve 2 9 is provided on the pipe 2 8. To avoid the loss of cold, in the present embodiment, an insulation layer 2 can be provided outside the pipe 2 8. The nitrogen outlet of the liquid nitrogen vaporizer 2 is connected to the input end of the buffer tank 20 through a pipe fitting, and the output end of the buffer tank 20 is connected to the nitrogen supply main pipe of the factory through a pipe fitting to provide nitrogen for lithium battery production. In the present embodiment, the liquid nitrogen vaporizer 2 adopts the existing technology and utilizes the principle of heat exchange to exchange heat between liquid nitrogen and a heat transfer medium, so that the liquid nitrogen absorbs heat and vaporizes into a gaseous state.

[0027] It should be noted that when valve five 18, valve six 19 and circulating pump two 17 are closed, the cooling water cooled by heat exchange through the heat exchanger 4 can also be provided only to the cold dryer 3; similarly, when valve three 13, valve four 14 are closed and circulating pump one 12 is turned off, the cooling water cooled by heat exchange through the heat exchanger 4 can also be provided only to the adsorption dryer 5.

[0028] It should be noted that valve one 7, valve two 9, valve three 13, and valve four 14 of this embodiment all adopt existing known electric flow control valves for pipelines, and their working principles are known and will not be described in detail here.

[0029] It should be noted that when a component is referred to as being "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component at the same time. When a component is considered to be "fixed to" another component, it may be directly fixed on the other component or there may be a central component at the same time.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0031] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0032] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A liquid nitrogen cold recovery and utilization device for an air compression system, comprising a liquid nitrogen tank (1) and a liquid nitrogen vaporizer (2), wherein the air compression system comprises a cold dryer (3), characterized in that: It also includes a heat exchanger (4), the cold source inlet of the heat exchanger (4) is connected to the liquid nitrogen outlet of the liquid nitrogen tank (1), and the cold source outlet is connected to the liquid nitrogen inlet of the liquid nitrogen vaporizer (2), the heat source inlet of the heat exchanger (4) is connected to the cooling water outlet of the cold dryer (3), and the heat source outlet is connected to the cooling water inlet of the cold dryer (3).

2. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 1, characterized in that: The air compression system also includes a desiccant (5), the heat source inlet of the heat exchanger (4) is connected to the cooling water outlet of the desiccant (5), and the heat source outlet is connected to the cooling water inlet of the desiccant (5).

3. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 1, characterized in that: The heat exchanger (4) is a shell and tube heat exchanger (4) or a plate heat exchanger (4).

4. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 1, characterized in that: The liquid nitrogen cold energy recovery and utilization device for an air compression system further comprises a pipeline (6), the two ends of which are respectively connected to the liquid nitrogen outlet of the liquid nitrogen tank (1) and the cold source inlet of the heat exchanger (4), and an insulation layer (1) is arranged outside the pipeline (6).

5. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 4, characterized in that: A valve (7) is provided on the pipeline (6).

6. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 1, characterized in that: The liquid nitrogen cold energy recovery and utilization device for an air compression system further comprises a second pipeline (8), the two ends of the second pipeline (8) are respectively connected to the cold source outlet of the heat exchanger (4) and the liquid nitrogen inlet of the liquid nitrogen vaporizer (2), and a second insulation layer is arranged outside the second pipeline (8).

7. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 6, characterized in that: A valve 2 (9) is provided on the pipeline 2 (8).

8. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 1, characterized in that: The liquid nitrogen cold recovery and utilization device for an air compression system further comprises a pipeline three (10), a pipeline four (11) and a circulation pump one (12); the two ends of the pipeline three (10) are respectively connected to the heat source inlet of the heat exchanger (4) and the cooling water outlet of the cold dryer (3); the two ends of the pipeline four (11) are respectively connected to the heat source outlet of the heat exchanger (4) and the cooling water inlet of the cold dryer (3); and a heat insulation layer three is arranged outside the pipeline four (11); and the inlet and outlet of the circulation pump one (12) are connected to the pipeline of the pipeline four (11).

9. The liquid nitrogen cooling capacity recovery and utilization device for an air compression system according to claim 8, characterized in that: Pipeline three (10) and pipeline four (11) are respectively provided with valve three (13) and valve four (14).

10. The liquid nitrogen cooling capacity recovery and utilization device for air compression system according to claim 2, characterized in that: The liquid nitrogen cold recovery and utilization device for an air compression system further comprises a pipeline five (15), a pipeline six (16) and a circulating pump two (17); the two ends of the pipeline five (15) are respectively connected to the heat source inlet of the heat exchanger (4) and the cooling water outlet of the desiccant machine (5); the two ends of the pipeline six (16) are respectively connected to the heat source outlet of the heat exchanger (4) and the cooling water inlet of the desiccant machine (5); and a heat-insulating layer four is arranged outside the pipeline six (16); the inlet and outlet of the circulating pump two (17) are connected to the pipeline of the pipeline six (16); and valves five (18) and six (19) are respectively arranged on the pipeline five (15) and the pipeline six (16).

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