Oxygen-enriched air recycling system of cryogenic nitrogen making device

Abstract

Compared with a traditional mode that by-product oxygen-enriched air generated by a nitrogen making unit is directly emptied, the oxygen-enriched air recycling system of the cryogenic nitrogen making device has the advantages that the oxygen-enriched air subjected to dehydration, pressurization and purification treatment is subjected to dehydration and pressurization treatment through a by-product pipeline; the oxygen is introduced into a heating furnace, a boiler and the like for combustion supporting, chemical production or other occasions needing oxygen to be recycled, so that the multiple purposes of maximum recycling of resources, effective auxiliary combustion, remarkable reduction of energy consumption, environment-friendly protection and the like are achieved; furthermore, by additionally arranging a by-product branch pipe in parallel connection with an air expansion machine and a heat exchanger, oxygen-enriched air waste heat is efficiently utilized, heat exchange is carried out on a cooling medium, raw material air introduced into the rectifying tower and a nitrogen product produced by the rectifying tower through the heat exchanger, the initial temperature of the raw material air is increased, and the heat exchange efficiency is improved. Therefore, the heat efficiency of the whole nitrogen generation system is obviously improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to high -purity nitrogen preparation technical field, concretely relates to a kind of oxygen-enriched air recovery and utilization system of deep-cooling nitrogen preparation device. BACKGROUND

[0002] The existing deep-cooling nitrogen preparation device produces by-products such as oxygen-enriched air while preparing nitrogen. The traditional treatment method is to directly empty the oxygen-enriched air, but this method has the following defects:

[0003] Resource waste: The oxygen-enriched air contains a high concentration of oxygen, and direct emptying means wasting this valuable resource. In the context of increasing energy and resource shortages, such waste is obviously unreasonable.

[0004] Environmental impact: Although the oxygen-enriched air has limited direct impact on the environment, a large amount of emptying can still cause some burden on the environment. For example, noise, heat emissions, etc. during the emptying process can have adverse effects on the surrounding environment.

[0005] Potential safety risks: Oxygen-enriched air has high flammability, and if not handled properly during emptying, it can cause fires and other safety incidents. This safety risk is even more unacceptable in some industrial environments.

[0006] Loss of economic benefits: With the continuous development of nitrogen production technology, the recovery and utilization of by-products such as oxygen-enriched air has become possible. Through proper handling and utilization, oxygen-enriched air can be converted into valuable resources, bringing additional economic benefits to the enterprise. Direct emptying means giving up this potential economic benefit.

[0007] The above information disclosed in the background section is only used to enhance the understanding of the background of the technology described herein, therefore, the background section may contain some information that is not considered prior art by those skilled in the art in the country. Utility model content

[0008] To solve the defects of the prior art, the utility model provides an oxygen-enriched air recovery and utilization system for a deep-cooling nitrogen preparation device.

[0009] The technical solution adopted by the utility model is as follows:

[0010] An oxygen-enriched air recovery and utilization system for a deep-cooling nitrogen preparation device, comprising:

[0011] A nitrogen production unit composed of a C1 rectification tower and a C2 rectification tower connected in series;

[0012] A by-product pipeline connected to the C2 rectification tower in the nitrogen production unit, with oxygen-enriched air in the pipeline;

[0013] The by-product pipeline end is further connected with a drying separator and a blower in sequence.

[0014] Through the above structure, the 35% content of the generated oxygen-enriched air is dehydrated and pressurized to be sent to combustion-supporting, chemical production or other occasions requiring oxygen (such as a heating furnace, a boiler), so as to realize the purposes of resource recycling, auxiliary combustion, energy consumption reduction and environment-friendly protection.

[0015] Preferably, a by-product branch pipe is further arranged on the by-product pipeline in parallel, and an air expander and a heat exchanger are arranged on the by-product branch pipe in sequence; the raw material air inlet pipe of the nitrogen production unit and the nitrogen product exhaust pipe are connected with the heat exchanger. Through the above, a part of the oxygen-enriched air is heat-recovered through the by-product branch pipe, and the heat exchanger is responsible for heat exchange between the cooling medium and the raw material air entering the rectifying tower and the nitrogen product produced by the rectifying tower, so as to improve the initial temperature of the raw material air and further improve the heat efficiency of the rectifying tower system.

[0016] Preferably, an electric heater and a molecular sieve adsorber are further arranged on the by-product pipeline, the molecular sieve adsorber is further used for removing impurities and moisture in the oxygen-enriched air, the electric heater is used for heating the oxygen-enriched air to a target temperature of 165-200 degrees, so as to ensure the best working state of the molecular sieve adsorber, and the treated oxygen-enriched air is connected to the drying separator through a pipeline for dehydration treatment.

[0017] Further, a valve II is arranged on the by-product pipeline, and the valve II is located at the rear side pipeline of the molecular sieve adsorber.

[0018] Further, a valve I is arranged on the by-product pipeline.

[0019] Further, a valve III is arranged on the front side pipeline of the drying separator.

[0020] Further, a valve IV is arranged on the pipeline between the drying separator and the blower.

[0021] In summary, due to the adoption of the above technical scheme, the beneficial effects of the present application are as follows:

[0022] Compared with the prior art, the oxygen-enriched air recycling system of the deep-cold nitrogen production device has the following advantages: compared with the traditional method of directly emptying the by-product oxygen-enriched air generated by the nitrogen production unit, the system further introduces the oxygen-enriched air after dehydration, pressurization and purification treatment into a heating furnace, a boiler or other places requiring oxygen for combustion, chemical production or other purposes through the by-product pipeline after dehydration and pressurization treatment, so as to realize the maximization of resource recycling, effective auxiliary combustion, significant reduction of energy consumption, friendly protection of the environment and other purposes; further, the by-product branch pipe is additionally provided in parallel with the air expander and the heat exchanger, so that the oxygen-enriched air waste heat is efficiently utilized, the cooling medium is heat-exchanged with the raw material air introduced into the rectifying tower and the nitrogen product produced by the rectifying tower through the heat exchanger, the initial temperature of the raw material air is improved, and the thermal efficiency of the entire nitrogen production system is significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0023] The utility model will be through example and the mode of referring to the drawing, wherein:

[0024] Figure 1 It is the structure diagram of oxygen-enriched air recycling system in the utility model. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantage of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0026] Embodiment 1

[0027] The embodiment provides an oxygen-enriched air recycling system of a deep-cold nitrogen production device, referring to Figure 1 , comprising:

[0028] The nitrogen production unit is a technology known in the art, which is composed of a precisely designed C1 rectifying tower and a C2 rectifying tower in series, and nitrogen is effectively extracted through deep-cold separation technology, and oxygen-enriched by-product, oxygen-enriched air, is generated at the same time;

[0029] The byproduct pipeline is directly connected to the outlet of the C2 rectification tower and is responsible for transporting oxygen-rich air containing about 35% oxygen. This pipeline not only achieves the preliminary collection of oxygen-rich air but also provides a foundation for subsequent recycling;

[0030] At the end of the byproduct pipeline, a high-efficiency drying separator is installed to completely remove the residual moisture in the oxygen-rich air, ensuring the quality of the output gas. Subsequently, a blower pressurizes the processed oxygen-rich air to provide power for long-distance transportation or specific application scenarios.

[0031] Through the above structure, the 35% oxygen-rich air generated is dehydrated and pressurized to be used for combustion support, chemical production, or other occasions requiring oxygen (such as furnaces, boilers), thereby achieving the purposes of resource recycling, auxiliary combustion, energy consumption reduction, and environmental friendly protection.

[0032] Example 2

[0033] This embodiment further refines the heat recovery and gas purification process in the oxygen-rich air recycling system of the deep cold nitrogen production device, aiming to achieve higher energy efficiency and environmental friendliness by efficiently utilizing the waste heat of oxygen-rich air and improving gas quality.

[0034] Referring to Figure 1 On the byproduct pipeline, we ingeniously connected a byproduct branch pipe, on which an air expander and a heat exchanger are installed in sequence. This design allows a portion of the oxygen-rich air to pass through the branch pipe for heat recovery:

[0035] Air expander: When the oxygen-rich air passes through the air expander, it expands and releases cold energy. This cold energy is effectively utilized to provide cooling medium for the subsequent heat exchanger.

[0036] Heat exchanger: The heat exchanger is a key device for heat recovery. Here, the cooling medium (i.e., the oxygen-rich air cooled by the air expander) exchanges heat with the raw air of the nitrogen production unit and the nitrogen product. The raw air is preheated before entering the rectification tower, increasing its initial temperature and reducing the energy consumption required in the rectification process. At the same time, the nitrogen product is appropriately cooled when discharged, which helps subsequent storage and transportation.

[0037] Through this design, we achieve efficient utilization of the waste heat of oxygen-rich air, not only increasing the initial temperature of the raw air but also reducing the temperature of the nitrogen product, thereby improving the thermal efficiency of the entire nitrogen production system.

[0038] Example 3

[0039] Based on the technical solutions of Examples 1 and 2, to further improve the quality of oxygen-rich air, referring to Figure 1We also added an electric heater and a molecular sieve adsorber to the byproduct pipeline:

[0040] Electric heater: The electric heater is used to heat the oxygen-enriched air to the target temperature range (165-200°C). This temperature range is one of the conditions for the optimal operation of the molecular sieve adsorber, which helps the adsorber to more effectively remove impurities and moisture from the oxygen-enriched air.

[0041] Molecular sieve adsorber: The molecular sieve adsorber is a highly efficient gas purification device. Here, the impurities (such as dust, oil mist, etc.) and moisture in the oxygen-enriched air are effectively removed by the molecular sieve adsorber after being heated. This step ensures the purity and quality of the oxygen-enriched air, providing reliable protection for subsequent applications.

[0042] After the oxygen-enriched air is treated by the electric heater and the molecular sieve adsorber, it is connected to the drying separator through the pipeline for dehydration treatment. The drying separator further removes the residual moisture in the gas, ensuring the dryness of the oxygen-enriched air, thereby meeting the high requirements of subsequent applications for gas quality.

[0043] By optimizing the heat recovery system and gas purification system in Examples 2 and 3, efficient utilization and high-quality output of oxygen-enriched air are achieved. This design not only improves the thermal efficiency of the nitrogen production system, but also reduces energy consumption and environmental pollution, providing a more efficient and environmentally friendly solution for the recovery and utilization of oxygen-enriched air in deep cold nitrogen production devices.

[0044] Example 4

[0045] This example is based on the previous examples, and further introduces a valve control system to achieve precise control and safety protection of each key link in the oxygen-enriched air recovery and utilization process. This design aims to improve the flexibility and reliability of the system, ensuring efficient and stable operation under various working conditions.

[0046] Valve I:

[0047] Location: Start of byproduct pipeline.

[0048] Function: As the first control point after the oxygen-enriched air flows out of the C2 rectifying column, Valve I is responsible for controlling the flow of oxygen-enriched air into the subsequent treatment process (including the byproduct branch, electric heater, molecular sieve adsorber, etc.). By adjusting the opening of Valve I, precise control of the oxygen-enriched air flow can be achieved to meet the needs of different application scenarios.

[0049] Valve II:

[0050] Location: Pipeline behind the molecular sieve adsorber.

[0051] Function: Valve II is located after the molecular sieve adsorber and is used to control the flow of purified oxygen-rich air into the drying separator. When the molecular sieve adsorber needs maintenance or replacement, closing valve II can cut off the gas flow to ensure the safety of the operators. At the same time, valve II can also be used to adjust the gas pressure entering the drying separator to adapt to different working conditions.

[0052] Valve III:

[0053] Location: Drying separator front side pipeline.

[0054] Function: Valve III serves as the inlet control valve of the drying separator, responsible for controlling the flow of oxygen-rich air entering the drying separator. When the drying separator needs to be shut down for maintenance or replacement, closing valve III can cut off the gas flow to prevent moisture or other impurities from entering the subsequent process. In addition, valve III can also be used to adjust the gas temperature entering the drying separator to ensure its optimal working state.

[0055] Valve IV:

[0056] Location: Pipeline between the drying separator and the fan.

[0057] Function: Valve IV serves as the last control point of the oxygen-rich air recycling process, responsible for controlling the flow of oxygen-rich air after drying into the fan. When the fan is shut down or needs maintenance, closing valve IV can cut off the gas flow to ensure the safe operation of the fan. At the same time, valve IV can also be used to adjust the gas pressure entering the fan to meet the needs of different application scenarios.

[0058] Advantages of the valve control system:

[0059] Improved system flexibility: By precisely controlling the opening of each valve, flexible adjustment of each link in the oxygen-rich air recycling process can be achieved to meet the needs of different working conditions.

[0060] Enhanced system safety: During equipment maintenance, replacement, or shutdown for maintenance, closing the corresponding valve can cut off the gas flow to ensure the safety of the operators.

[0061] Optimized system performance: By adjusting the opening of the valve, precise control of oxygen-rich air flow, pressure, and temperature can be achieved to optimize the overall performance of the system and improve energy utilization efficiency.

[0062] Convenient troubleshooting and maintenance: The introduction of the valve control system makes troubleshooting and maintenance work more convenient. When a fault occurs, the problem can be quickly located by observing the state and parameter changes of each valve, and effective measures can be taken for repair.

[0063] To sum up, by introducing the valve control system, the precise control and safety protection of each link in the oxygen-enriched air recycling process are realized. This design not only improves the flexibility and reliability of the system, but also optimizes the system performance, and provides a more efficient and safe solution for the oxygen-enriched air recycling of the cryogenic nitrogen generation device.

[0064] The above-described embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A deep cooling nitrogen production device oxygen-enriched air recycling system, characterized in that, The application relates to a nitrogen production unit and a method for producing nitrogen. The nitrogen production unit is composed of a C1 rectifying tower and a C2 rectifying tower arranged in series. A by-product pipeline is connected with the C2 rectifying tower in the nitrogen production unit, and the pipeline is filled with oxygen-rich air. The end of the by-product pipeline is further connected with a drying separator and a blower in sequence. A by-product branch pipeline is further arranged on the by-product pipeline in parallel, and an air expander and a heat exchanger are arranged on the by-product branch pipeline in sequence.

2. The system according to claim 1, wherein, The by-product pipeline is provided with a valve I.

3. The system of claim 1, wherein the system further comprises a compressor. An electric heater and a molecular sieve adsorber are further arranged on the by-product pipeline.

4. The system of claim 1, wherein the system further comprises a compressor. A valve II is arranged on the by-product pipeline, and the valve II is located on the rear pipeline of the molecular sieve adsorber.

5. The system of claim 1, wherein the system further comprises a compressor. A valve III is arranged on the front pipeline of the drying separator.

6. The system of claim 1, wherein the system further comprises a compressor. A valve IV is arranged on the pipeline between the drying separator and the blower.

Images