Heat utilization system for liquid nitrogen production

Abstract

The utility model relates to energy utilization technical field, concretely relates to a heat utilization system of liquid nitrogen production. The heat utilization system includes: air compression mechanism, is provided with air input end and air output end, and exports compressed air through air output end, liquid nitrogen production mechanism is provided with first end and second end, the first end of liquid nitrogen production mechanism is connected with air output end, the second end of liquid nitrogen production mechanism exports liquid nitrogen outward, heat exchange mechanism is provided with heat absorption side and heat exchange side, heat absorption side with air compression mechanism, liquid nitrogen production mechanism contact heat exchange, heat utilization mechanism with heat exchange side contact heat exchange. This embodiment sets up heat exchange mechanism, can collect the heat of air compression mechanism and liquid nitrogen production mechanism simultaneously, then the heat is transferred to heat utilization mechanism, thereby can utilize the heat released in the process of making nitrogen, avoids the waste of heat.

Description

Technical Field

[0001] This utility model relates to the field of energy utilization technology, specifically to a heat utilization system for liquid nitrogen production. Background Technology

[0002] Currently, during the production of liquid nitrogen, gas condensation and heat release occur during the nitrogen production process, and nitrogen production equipment, such as refrigeration units, release a large amount of heat when compressing nitrogen. This heat is rarely discussed in terms of how to utilize it, resulting in heat waste. Utility Model Content

[0003] In view of this, the present invention provides a heat utilization system for liquid nitrogen production to solve the problem of heat waste in the nitrogen production process.

[0004] In a first aspect, this utility model provides a heat utilization system for liquid nitrogen production, the heat utilization system comprising:

[0005] An air compression mechanism is provided with an air inlet and an air outlet, and outputs compressed air through the air outlet.

[0006] A liquid nitrogen production mechanism is provided with a first end and a second end; the first end of the liquid nitrogen production mechanism is connected to the air output end, and the second end of the liquid nitrogen production mechanism outputs liquid nitrogen to the outside;

[0007] The heat exchange mechanism is provided with a heat absorption side and a heat exchange side; the heat absorption side exchanges heat with the air compression mechanism and the liquid nitrogen production mechanism.

[0008] The heat utilization mechanism contacts the heat exchange side for heat exchange.

[0009] Beneficial effects: This embodiment is equipped with a heat exchange mechanism, which can collect the heat generated by the air compression mechanism and the liquid nitrogen production mechanism at the same time, and then transfer the heat to the heat utilization mechanism, so that the heat released during the nitrogen production process can be utilized and heat waste is avoided.

[0010] In one optional embodiment, the air compression mechanism includes:

[0011] An air compressor is provided with an input side and an output side; the input side is the air input terminal.

[0012] An air filter assembly, wherein a first end of the air filter assembly is connected to the output side, and a second end of the air filter assembly is the air output end;

[0013] The air filter assembly exchanges heat with the heat-absorbing side through contact.

[0014] Beneficial effects: By setting up an air filter component, this embodiment can utilize the high adsorption capacity of the filter component to remove impurities such as oil and water carried in the gas, thereby ensuring the purity of liquid nitrogen in the subsequent liquid nitrogen production process.

[0015] In one optional embodiment, the air filtration assembly includes a demister, a filter, and an air buffer tank connected in series, wherein the demister is connected to the output side, and the output port of the air buffer tank is the air output end.

[0016] Beneficial effects: This embodiment is equipped with an air buffer tank, which allows high-temperature and high-pressure gas to be introduced into the air buffer tank. The air buffer tank absorbs and releases energy to balance pressure fluctuations and ensures the stable operation of the subsequent liquid nitrogen production process.

[0017] In one alternative embodiment, in the air compression mechanism, the heat-absorbing side only exchanges heat with the demister and the air buffer tank.

[0018] Beneficial effects: During air compression, the high-temperature, high-pressure gas comes into contact with the low-temperature outer wall in the demister and air buffer tank, resulting in condensation. Since the condensation of the high-temperature, high-pressure gas releases heat, this embodiment ensures that the heat-absorbing side only exchanges heat with the demister and air buffer tank in the air compression mechanism, thereby improving the overall heat exchange efficiency of the heat-absorbing side.

[0019] In one alternative embodiment, the liquid nitrogen production facility includes:

[0020] A nitrogen production assembly, wherein a first end of the nitrogen production assembly is connected to the air output end; the nitrogen production assembly is used to perform adsorption and desorption cycles on air to continuously generate nitrogen, which is then output to the outside through a second end of the nitrogen production assembly.

[0021] A liquid nitrogen generating component is connected to the second end of the nitrogen production component; the liquid nitrogen generating component is used to compress and liquefy the input nitrogen.

[0022] In one alternative embodiment, the nitrogen production assembly includes:

[0023] An adsorption assembly includes multiple adsorption containers arranged in parallel; the first end of the adsorption assembly is connected to the air output end.

[0024] A nitrogen buffer is connected to the second end of the adsorption group;

[0025] A nitrogen filter is connected to the output of the nitrogen buffer.

[0026] In one alternative embodiment, a series-parallel switching valve assembly is also provided between the multiple adsorption containers.

[0027] In one optional embodiment, the liquid nitrogen generation component includes:

[0028] A nitrogen compressor is connected to the second end of the nitrogen production assembly;

[0029] A refrigeration unit is connected to the output end of the nitrogen compressor.

[0030] In one alternative embodiment, in the liquid nitrogen production facility, the heat-absorbing side only exchanges heat with the refrigerator.

[0031] In one optional embodiment, the heat exchange mechanism is an airflow heat exchange mechanism, which includes:

[0032] A fan; suitable for generating airflow; the airflow passes through the air compression mechanism and the liquid nitrogen production mechanism;

[0033] Multiple heat exchange components, each corresponding to the air compression mechanism and the liquid nitrogen production mechanism;

[0034] After passing through the air compression mechanism and the liquid nitrogen production mechanism, the airflow exchanges heat with the corresponding heat exchange components.

[0035] Beneficial effects: This embodiment employs multiple heat exchange components, each corresponding to the air compression mechanism and the liquid nitrogen production mechanism. This saves on the overall coverage of the heat exchange components while ensuring that each component is in as much complete contact as possible with the air compression mechanism and the liquid nitrogen production mechanism, thereby improving heat exchange efficiency. Furthermore, multiple heat exchange components can achieve multi-stage heat exchange, effectively avoiding heat waste.

[0036] In one alternative implementation, the heat utilization mechanism is used at least for cooling tower heat dissipation, heating workshop water, and heating ground source water. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of this utility model, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the structure of a heat utilization system for liquid nitrogen production in an embodiment of this utility model.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Air compression mechanism; 11. Air compressor; 12. Air filter assembly; 121. Demister; 122. Filter; 123. Air buffer tank;

[0041] 2. Liquid nitrogen production mechanism; 21. Nitrogen production assembly; 211. Adsorption group; 212. Nitrogen buffer; 213. Nitrogen filter; 214. Switch valve assembly; 22. Liquid nitrogen generation assembly; 221. Nitrogen compressor; 222. Refrigeration unit;

[0042] 3. Heat exchange mechanism; 31. Fan; 32. Heat exchange components;

[0043] 4. Heat utilization mechanism. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0045] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0046] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0047] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0048] Currently, there are several methods for producing liquid nitrogen: 1. Cryogenic air separation: Air is compressed into a liquid state, then pressurized at low temperature and fractionated by heating. In this process, nitrogen first evaporates from the liquid air, and the collected nitrogen is cooled and pressurized to obtain liquid nitrogen. 2. Carbon molecular sieve air separation (PSA): Using carbon molecular sieves as adsorbents, the principle of pressure swing adsorption is applied. Nitrogen and oxygen are separated by the selective adsorption of oxygen and nitrogen by the carbon molecular sieves. The separated nitrogen is then cooled and pressurized to obtain liquid nitrogen. 3. Membrane air separation: Using air as raw material, nitrogen and oxygen are separated under certain pressure conditions by utilizing the different permeabilities of gases with different properties, such as nitrogen and oxygen, in a membrane. Among these, the PSA method has a simple process flow, high degree of automation, fast gas production, low energy consumption, product purity that can be adjusted within a wide range according to user needs, convenient operation and maintenance, low operating costs, and strong adaptability, making it the preferred method for medium and small-sized nitrogen users.

[0049] However, when using the PSA nitrogen generation method, the nitrogen generation process (condensation heat release) and the nitrogen generation equipment (such as: chiller 222) release most of the heat. How to utilize this part of the heat is rarely mentioned at present, resulting in heat waste.

[0050] In view of this, the present invention provides a heat utilization system for liquid nitrogen production to solve the problem of heat waste in the nitrogen production process.

[0051] The following is combined with Figure 1 The following describes embodiments of the present invention.

[0052] According to an embodiment of the present invention, a heat utilization system for liquid nitrogen production is provided, the heat utilization system including an air compression mechanism 1, a liquid nitrogen production mechanism 2, a heat exchange mechanism 3, and a heat utilization mechanism 4.

[0053] Specifically, in this embodiment, the air compression mechanism 1 is provided with an air input end and an air output end, and outputs compressed air through the air output end. The liquid nitrogen production mechanism 2 is provided with a first end and a second end; the first end of the liquid nitrogen production mechanism 2 is connected to the air output end, and the second end of the liquid nitrogen production mechanism 2 outputs liquid nitrogen outward.

[0054] Furthermore, the heat exchange mechanism 3 is provided with a heat absorption side and a heat exchange side, wherein the heat absorption side contacts and exchanges heat with the air compression mechanism 1 and the liquid nitrogen production mechanism 2. In this embodiment, the heat exchange mechanism 3 can be a common liquid heat exchange method or an airflow heat exchange method. Of course, this embodiment is merely an example to illustrate the type of heat exchange mechanism 3, but it is not a limitation. Those skilled in the art can modify it according to the actual situation, as long as the same technical effect is achieved.

[0055] Furthermore, the heat utilization mechanism 4 contacts the heat exchange side for heat exchange. The heat utilization mechanism 4 can be used for heating residential areas, preheating production workshops, etc. Of course, this embodiment is merely an example of the type of heat utilization mechanism 4, but it is not intended to limit it. Those skilled in the art can modify it according to actual conditions, as long as the same technical effect is achieved.

[0056] With this configuration, the heat exchange mechanism 3 in this embodiment can collect the heat generated by the air compression mechanism 1 and the liquid nitrogen production mechanism 2 at the same time, and then transfer the heat to the heat utilization mechanism 4, so that the heat released during the nitrogen production process can be utilized and heat waste is avoided.

[0057] Furthermore, in an optional embodiment, the air compression mechanism 1 includes an air compressor 11 and an air filter assembly 12.

[0058] Specifically, the air compressor 11 has an input side and an output side, with the input side being the air input terminal. The first end of the air filter assembly 12 is connected to the output side, and the second end of the air filter assembly 12 is the air output terminal. The air filter assembly 12 exchanges heat with the heat-absorbing side through contact.

[0059] With this configuration, this embodiment can utilize the high adsorption capacity of the air filter component 12 to remove impurities such as oil and water carried in the gas, thereby ensuring the purity of liquid nitrogen in the subsequent liquid nitrogen production process.

[0060] Furthermore, in an optional embodiment, the air filtration assembly 12 includes a demister 121, a filter 122, and an air buffer tank 123 connected in series. The demister 121 is connected to the output side, and the output port of the air buffer tank 123 is the air output end.

[0061] With this configuration, this embodiment includes an air buffer tank 123, into which high-temperature and high-pressure gas can be introduced. The air buffer tank 123 absorbs and releases energy to balance pressure fluctuations, ensuring the stable operation of the subsequent liquid nitrogen production process.

[0062] Furthermore, in an optional embodiment, in the air compression mechanism 1, the heat-absorbing side only exchanges heat with the demister 121 and the air buffer tank 123.

[0063] With this configuration, during air compression, the high-temperature, high-pressure gas will come into contact with the low-temperature outer wall in the demister 121 and air buffer tank 123, resulting in condensation. Since the high-temperature, high-pressure gas releases heat during condensation, this embodiment ensures that the heat-absorbing side only exchanges heat with the demister 121 and air buffer tank 123 in the air compression mechanism 1, thereby improving the overall heat exchange efficiency of the heat-absorbing side.

[0064] Furthermore, in an optional embodiment, the liquid nitrogen production mechanism 2 includes a nitrogen production component 21 and a liquid nitrogen generation component 22.

[0065] Specifically, the first end of the nitrogen production component 21 is connected to the air output end; the nitrogen production component 21 is used to perform adsorption and desorption cycles on air to continuously generate nitrogen, which is then output to the outside through the second end of the nitrogen production component 21. The liquid nitrogen generation component 22 is connected to the second end of the nitrogen production component 21; the liquid nitrogen generation component 22 is used to compress and liquefy the input nitrogen.

[0066] Furthermore, in an optional embodiment, the nitrogen production assembly 21 includes an adsorption group 211, a nitrogen buffer 212, and a nitrogen filter 213.

[0067] Specifically, the adsorption assembly 211 comprises multiple adsorption containers arranged in parallel; the first end of the adsorption assembly 211 is connected to the air output end. The adsorption containers use carbon molecular sieves as adsorbents and employ the pressure swing adsorption principle. This utilizes the selective adsorption of oxygen and nitrogen by the carbon molecular sieves to separate them. In other words, under high pressure, the carbon molecular sieves selectively adsorb oxygen, ensuring that the passing nitrogen reaches the required purity level. In this process, one container produces nitrogen, while another container removes the adsorbed oxygen under pressure and releases it into the atmosphere. Nitrogen is continuously produced through the adsorption and desorption cycle between the two adsorption beds.

[0068] Furthermore, the nitrogen buffer 212 is connected to the second end of the adsorption group 211, and the nitrogen filter 213 is connected to the output end of the nitrogen buffer 212.

[0069] Furthermore, in an optional embodiment, a series-parallel switching valve assembly 214 is also provided between the multiple adsorption containers. The direction of gas is controlled by adjusting the on / off state of the switching valves in the switching valve assembly 214.

[0070] Furthermore, in an optional embodiment, the liquid nitrogen generating component 22 includes a nitrogen compressor 221 and a refrigeration unit 222.

[0071] Specifically, the nitrogen compressor 221 is connected to the second end of the nitrogen production assembly 21, and the refrigeration unit 222 is connected to the output end of the nitrogen compressor 221.

[0072] Furthermore, in an optional embodiment, in the liquid nitrogen production unit 2, the heat-absorbing side only exchanges heat with the refrigerator 222.

[0073] Furthermore, in an optional embodiment, the heat exchange mechanism 3 is an airflow heat exchange mechanism 3, which includes a fan 31 and a plurality of heat exchange components 32.

[0074] Specifically, the fan 31 is adapted to generate airflow; the airflow passes through the air compression mechanism 1 and the liquid nitrogen production mechanism 2. Each heat exchange component 32 corresponds to the air compression mechanism 1 and the liquid nitrogen production mechanism 2. After passing through the air compression mechanism 1 and the liquid nitrogen production mechanism 2, the airflow exchanges heat with the corresponding heat exchange component 32.

[0075] In this configuration, multiple heat exchange components 32 are provided in this embodiment, with each heat exchange component 32 corresponding to the air compression mechanism 1 and the liquid nitrogen production mechanism 2. This saves on the overall coverage of the heat exchange components 32 while ensuring that each heat exchange component 32 is in as much complete contact as possible with the air compression mechanism 1 and the liquid nitrogen production mechanism 2, thereby improving heat exchange efficiency. Furthermore, multiple heat exchange components 32 can also achieve multi-stage heat exchange, effectively avoiding heat waste.

[0076] Furthermore, in an optional embodiment, the heat utilization mechanism 4 is used at least for cooling tower heat dissipation, heating workshop water, and heating ground source water.

[0077] The specific workflow of this embodiment is as follows:

[0078] Air is fed into air compressor 11 for compression. The resulting high-temperature, high-pressure air is then passed into demister 121 to remove water mist, and then into filter 122. The activated carbon in filter 122 adsorbs impurities such as oil and water carried in the gas. The high-temperature, high-pressure gas is then passed into air buffer tank 123, where pressure fluctuations are balanced by absorbing and releasing energy.

[0079] The gas flow is controlled by adjusting the switching valve assembly 214. During this process, trace impurities, such as carbon dioxide and residual moisture, are adsorbed by the carbon molecular sieve located at the inlet of the adsorption bed in the adsorption container. Under high pressure, the carbon molecular sieve selectively adsorbs oxygen, ensuring the nitrogen gas reaches the required purity level. In this process, one container produces nitrogen, while the other removes adsorbed oxygen under pressure and discharges it into the atmosphere through the exhaust port. Nitrogen gas is continuously produced through the adsorption and desorption cycle between the two adsorption beds.

[0080] The generated nitrogen gas is then introduced into a nitrogen buffer 212, where it absorbs and releases energy to balance pressure fluctuations. After being filtered by a nitrogen filter 213, the nitrogen gas is compressed by a nitrogen compressor 221. The liquid nitrogen compressor then discharges high-temperature, high-pressure nitrogen gas, which is then liquefied and cooled by a refrigerator 222. Finally, the nitrogen pressure can be reduced by a final pressure reducing valve to completely liquefy the gas.

[0081] During heat exchange, a fan 31 blows air into the heat absorption side of each heat exchange component 32. The heat exchange side of each heat exchange component 32 is connected to a heat utilization mechanism 4, such as the outlet and inlet of a cooling tower, the outlet and inlet of a ground source water source, or the outlet and inlet of workshop water. Through this connection method, the heat released by the condensation of high-temperature gas and the heat released during the operation of the chiller 222 can be fully utilized.

[0082] Specifically, it can dissipate heat from the cooling tower in summer, heat the ground source water in winter, and heat the workshop water in winter, which is then supplied to the workshop for use during winter.

[0083] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A heat utilization system for liquid nitrogen production, characterized in that, include: An air compression mechanism (1) is provided with an air input end and an air output end, and outputs compressed air through the air output end; A liquid nitrogen production mechanism (2) is provided with a first end and a second end; the first end of the liquid nitrogen production mechanism (2) is connected to the air output end, and the second end of the liquid nitrogen production mechanism (2) outputs liquid nitrogen outward; The heat exchange mechanism (3) is provided with a heat absorption side and a heat exchange side; the heat absorption side is in contact with the air compression mechanism (1) and the liquid nitrogen production mechanism (2) for heat exchange; The heat utilization mechanism (4) contacts the heat exchange side for heat exchange.

2. The heat utilization system according to claim 1, characterized in that, The air compression mechanism (1) includes: An air compressor (11) is provided with an input side and an output side; the input side is the air input terminal; An air filter assembly (12) is provided, wherein the first end of the air filter assembly (12) is connected to the output side, and the second end of the air filter assembly (12) is the air output end. The air filter assembly (12) exchanges heat with the heat-absorbing side.

3. The heat utilization system according to claim 2, characterized in that, The air filtration assembly (12) includes a demister (121), a filter (122), and an air buffer tank (123) connected in series. The demister (121) is connected to the output side, and the output port of the air buffer tank (123) is the air output end.

4. The heat utilization system according to claim 3, characterized in that, In the air compression mechanism (1), the heat-absorbing side only exchanges heat with the demister (121) and the air buffer tank (123).

5. The heat utilization system according to any one of claims 1 to 4, characterized in that, The liquid nitrogen production facility (2) includes: A nitrogen production assembly (21) is provided, with its first end connected to the air output end. The nitrogen production assembly (21) is used to perform adsorption and desorption cycles on air to continuously generate nitrogen, which is then output to the outside through its second end. A liquid nitrogen generating component (22) is connected to the second end of the nitrogen production component (21); the liquid nitrogen generating component (22) is used to compress and liquefy the input nitrogen.

6. The heat utilization system according to claim 5, characterized in that, The nitrogen production assembly (21) includes: The adsorption group (211) includes multiple adsorption containers arranged in parallel; the first end of the adsorption group (211) is connected to the air output end; A nitrogen buffer (212) is connected to the second end of the adsorption group (211); A nitrogen filter (213) is connected to the output end of the nitrogen buffer (212); a series-parallel switching valve group (214) is also provided between the multiple adsorption containers.

7. The heat utilization system according to claim 6, characterized in that, The liquid nitrogen generation component (22) includes: A nitrogen compressor (221) is connected to the second end of the nitrogen production assembly (21); The refrigeration unit (222) is connected to the output end of the nitrogen compressor (221).

8. The heat utilization system according to claim 7, characterized in that, In the liquid nitrogen production unit (2), the heat-absorbing side only exchanges heat with the refrigerator (222).

9. The heat utilization system according to any one of claims 1 to 4, characterized in that, The heat exchange mechanism (3) is an airflow heat exchange mechanism (3), which includes: A fan (31); adapted to generate airflow; the airflow passes through the air compression mechanism (1) and the liquid nitrogen production mechanism (2); Multiple heat exchange components (32), each heat exchange component (32) corresponding to the air compression mechanism (1) and the liquid nitrogen production mechanism (2); After passing through the air compression mechanism (1) and the liquid nitrogen production mechanism (2), the airflow exchanges heat with the corresponding heat exchange components (32).

10. The heat utilization system according to any one of claims 1 to 4, characterized in that, The heat utilization mechanism (4) is used at least for cooling tower heat dissipation, heating workshop water, and heating ground source water.

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