Regenerated exhaust recycling system of pressure swing adsorption nitrogen making machine

Abstract

The utility model relates to a regeneration exhaust recycling system of a pressure swing adsorption nitrogen making machine, which comprises the pressure swing adsorption nitrogen making machine, a branch pipe is arranged at the tail end of an exhaust port of the pressure swing adsorption nitrogen making machine, the branch pipe is connected to the inlet side of a buffer tank, and the outlet side of the buffer tank is connected to an air return pipe of a dehumidifier. Pressure swing adsorption nitrogen making and the dehumidifier are combined, and regenerated exhaust of the pressure swing adsorption nitrogen making machine is conveyed to the air return system of the dehumidifier, so that the fresh air inlet amount of the dehumidifier is reduced, and the energy consumption of the dehumidifier is reduced; and meanwhile, the regeneration process of the pressure swing adsorption nitrogen making machine is accelerated by utilizing the air return negative pressure suction effect of the dehumidifier.

Description

Technical Field

[0001] This utility model relates to a system for recovering and utilizing exhaust gas from a pressure swing adsorption nitrogen generator, belonging to the field of recycling technology. Background Technology

[0002] Nitrogen is used extensively as a protective gas in lithium battery production. Dehumidifiers are also used to reduce humidity in the workshop to maintain the required production environment. Nitrogen is typically produced using a pressure swing adsorption (PSA) nitrogen generator from dried compressed air. Other gases are discharged outside the system via a PSA process. PSA involves two main processes: atmospheric pressure desorption and negative pressure desorption. Negative pressure desorption has a higher desorption rate than atmospheric pressure desorption, but it increases energy consumption. Dehumidifiers remove moisture from the air through refrigeration and rotary dehumidification to produce dry air. During air circulation, 10%–20% fresh air needs to be added to compensate for workshop leakage and personnel respiration. Utility Model Content

[0003] The purpose of this invention is to provide a pressure swing adsorption (PSA) nitrogen generator regeneration exhaust gas recovery and utilization system. By combining the PSA nitrogen generator and the dehumidifier, the dry gas generated during the PSA nitrogen generator desorption process is transported to the dehumidifier return air duct, making full use of the residual value of the dry compressed air. At the same time, the negative pressure suction effect of the dehumidifier return air duct provides negative pressure for the PSA nitrogen generator desorption process, accelerating the desorption process and achieving efficient energy utilization between the equipment.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] This utility model provides a pressure swing adsorption (PSA) nitrogen generator regeneration exhaust gas recovery and utilization system, including a PSA nitrogen generator, wherein a branch pipe is installed at the end of the exhaust port of the PSA nitrogen generator, and the branch pipe is connected to the dehumidifier return air duct.

[0006] Preferably, the system includes at least two pressure swing adsorption (PSA) nitrogen generators, each of which has a branch pipe installed at the end of its exhaust port. The branch pipes are then connected to the dehumidifier return air duct. After desorption, the exhaust gas from the PSA nitrogen generator enters the dehumidifier return air duct and is treated together with the workshop return air. The mixed fresh air is then sent to the workshop through the dehumidifier supply air duct to prevent the exhaust gas dew point from failing to meet the standard and affecting the workshop.

[0007] In this preferred embodiment, multiple pressure swing adsorption tanks are used to work alternately, which can ensure a stable gas supply.

[0008] Preferably, the system further includes a regenerated exhaust gas recovery main pipe and a buffer tank; the branch pipes converge at the regenerated exhaust gas recovery main pipe and are then connected to the inlet side of the buffer tank, and the outlet side of the buffer tank is connected to the dehumidifier return air duct through the regenerated exhaust gas recovery main pipe.

[0009] In this preferred embodiment, in order to balance the volume of exhaust gas and reduce the impact of uneven gas volume on the downstream dehumidifier, a buffer tank is set up to buffer the exhaust gas and smooth out peak and valley flows.

[0010] Preferably, a valve is also provided on the branch pipe at the end of the exhaust port of each of the pressure swing adsorption nitrogen generators.

[0011] The valves are opened and closed alternately to enable the pressure swing adsorption nitrogen generator to work alternately, using compressed air with a pressure dew point temperature below -70℃ as the feedstock to produce nitrogen.

[0012] In this preferred embodiment, two pressure swing adsorption tanks are used to work alternately, and valves are used to switch alternately with the desorption process of the nitrogen generator to prevent the two pressure swing adsorption nitrogen generators from affecting each other during operation.

[0013] Preferably, a one-way valve is provided on the regeneration exhaust recovery main pipe on the outlet side of the buffer tank, and the direction of the one-way valve is from the buffer tank to the dehumidifier return air pipe.

[0014] In this preferred embodiment, a one-way valve is installed, with the valve pointing from the buffer tank to the dehumidifier return air duct, to prevent the dehumidifier airflow from blowing back into the buffer tank.

[0015] Preferably, a regeneration exhaust gas recovery main valve is provided before the regeneration exhaust gas recovery main pipe enters the dehumidifier at the rear end of the one-way valve;

[0016] The main valve for regenerated exhaust gas recovery is normally open and closes when the equipment is under maintenance or the system is disconnected.

[0017] In this preferred embodiment, a main valve for regenerated exhaust gas recovery is installed to close when the exhaust gas reuse system is disconnected from the dehumidifier, facilitating maintenance of the dehumidifier or pressure swing adsorption nitrogen generator.

[0018] Preferably, a flow meter is installed at the rear end of the regenerated exhaust gas recovery main valve before the regenerated exhaust gas recovery main pipe enters the dehumidifier;

[0019] The flow meter is used to detect the flow rate before it enters the dehumidifier and feeds the flow data back to the dehumidifier's central control system.

[0020] In this preferred embodiment, the flow rate signal measured by the flow meter is fed back to the dehumidifier's central control system to adjust the fresh air intake of the dehumidifier.

[0021] Preferably, the buffer tank is equipped with a normally closed maintenance valve, which is opened only when the dehumidifier stops but the pressure swing adsorption nitrogen generator continues to operate.

[0022] In this preferred embodiment, a normally closed maintenance valve is installed on the buffer tank for the nitrogen generator to operate independently, thus maintaining the normal operation of the nitrogen generator.

[0023] Preferably, the buffer tank is installed on the ground and fixed with a steel frame.

[0024] Preferably, the wall thickness of the buffer container is greater than 5 mm.

[0025] In this preferred embodiment, to reduce the vibration of the buffer tank caused by uneven exhaust gas flow, the buffer tank should be installed on the ground and fixed with a steel frame. At the same time, the wall thickness of the buffer tank should be greater than 5mm to reduce tank wall vibration.

[0026] The beneficial effects of this utility model are as follows:

[0027] This invention provides a system for recovering and utilizing the regenerated exhaust gas from a pressure swing adsorption (PSA) nitrogen generator. By combining the PSA nitrogen generator and a dehumidifier, the dry gas generated during the PSA nitrogen generator's desorption process is transported to the dehumidifier's return air duct, making full use of the residual value of the dry compressed air. At the same time, the negative pressure suction effect of the dehumidifier's return air duct provides negative pressure for the PSA nitrogen generator's desorption process, accelerating the desorption process and achieving efficient energy utilization between the equipment. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a regeneration exhaust gas recovery system for a pressure swing adsorption nitrogen generator provided in one embodiment of the present invention;

[0029] In the diagram: 101-Pressure Swing Adsorption (PSA) Nitrogen Generator 1, 102-Pressure Swing Adsorption (PSA) Nitrogen Generator 1 valve, 103-Pressure Swing Adsorption (PSA) Nitrogen Generator Branch Pipe, 201-Pressure Swing Adsorption (PSA) Nitrogen Generator 2, 202-Pressure Swing Adsorption (PSA) Nitrogen Generator 2 valve, 203-Pressure Swing Adsorption (PSA) Nitrogen Generator 2 Branch Pipe, 301-Regeneration Exhaust Recovery Main Pipe, 302-Check Valve, 303-Regeneration Exhaust Recovery Main Pipe Valve, 304-Buffer Tank, 305-Normally Closed Maintenance Valve, 306-Flow Meter, 401-Dehumidifier Return Air Pipe, 402-Dehumidifier Supply Air Pipe, 403-Dehumidifier Fresh Air Pipe. Detailed Implementation

[0030] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The embodiments described below with reference to the accompanying drawings are illustrative and intended to explain this utility model, and should not be construed as limiting this utility model.

[0031] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "end", "bottom", "side", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0032] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "installation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a direct connection, or a connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0033] Secondly, the term "an embodiment" or "embodiment" as used in this utility model refers to a specific feature, structure, or characteristic that can be included in at least one implementation of this utility model. The phrase "in an embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.

[0034] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0035] Pressure Swing Adsorption (PSA) nitrogen generators separate air by utilizing the varying adsorption effects of adsorbents on gas molecules under different pressures, involving two main stages: adsorption and desorption. To ensure a stable gas supply, at least two PSA tanks are used, operating alternately. Conventional PSA tanks release exhaust gas during desorption through an exhaust port into the atmosphere. This invention installs a branch pipe at the end of the PSA nitrogen generator's exhaust port, connecting to the dehumidifier's return air duct. An electrically controlled valve is installed on the branch pipe, which collects the exhaust gas from the PSA nitrogen generator during desorption. The valve switches alternately with the nitrogen generator's desorption process, preventing mutual interference between the two PSA nitrogen generators during operation.

[0036] Based on the above concept, one embodiment of the pressure swing adsorption (PSA) nitrogen generator regeneration exhaust recovery system provides a system that uses two PSA tanks to work alternately. (See [link]). Figure 1It includes a pressure swing adsorption nitrogen generator 101, a pressure swing adsorption nitrogen generator valve 102, a pressure swing adsorption nitrogen generator branch pipe 103, a pressure swing adsorption nitrogen generator 201, a pressure swing adsorption nitrogen generator 2 valve 202, a pressure swing adsorption nitrogen generator 2 branch pipe 203, a regeneration exhaust recovery main pipe 301, a one-way valve 302, a regeneration exhaust recovery main pipe valve 303, a buffer tank 304, a normally closed maintenance valve 305, a flow meter 306, a dehumidifier return air duct 401, a dehumidifier supply air duct 402, and a dehumidifier fresh air duct 403.

[0037] Among them, a pressure swing adsorption nitrogen generator branch pipe 103 is installed at the end of the exhaust port of pressure swing adsorption nitrogen generator 101, and a pressure swing adsorption nitrogen generator branch pipe 203 is installed at the end of the exhaust port of pressure swing adsorption nitrogen generator 201. The two branch pipes are connected to the regeneration exhaust recovery main pipe 301 and then connected to the inlet side of the buffer tank 304. The outlet side of the buffer tank is connected to the dehumidifier return air pipe 401 through the regeneration exhaust recovery main pipe 301.

[0038] In this invention, the exhaust gas from the pressure swing adsorption nitrogen generator after desorption enters the dehumidifier return air duct 401 and is treated together with the workshop return air. The resulting fresh air is then sent to the workshop via the dehumidifier supply air duct 402 to prevent the exhaust gas dew point from failing to meet the standard and affecting the workshop.

[0039] In this embodiment, the buffer tank 304 is mainly used to balance the gas volume. In the initial stage of the desorption process, due to the large pressure difference between the inside and outside of the adsorbent, a large amount of waste gas is released during desorption. In the later stage, the pressure difference is small, and the amount of waste gas released during desorption is small. Furthermore, because the two pressure swing adsorption nitrogen generators work alternately, the waste gas volume exhibits alternating peaks and valleys. To balance the waste gas volume and reduce the impact of uneven gas volume on the downstream dehumidifier, a buffer tank is installed to buffer the waste gas and smooth out peaks and valleys.

[0040] In this embodiment, pressure swing adsorption (PSA) nitrogen generator 101 and pressure swing adsorption (PSA) nitrogen generator 201 operate alternately, using compressed air with a pressure dew point temperature below -70°C as the feedstock to produce nitrogen. The overall nitrogen production efficiency is approximately 1:5 to 1:6, with the remainder discharged as exhaust gas.

[0041] In one embodiment, a pressure swing adsorption (PSA) nitrogen generator 101 is provided with a PSA valve 102 on a branch pipe at the end of its exhaust port, and a PSA valve 202 is provided at the end of its exhaust port of a PSA nitrogen generator 201. The PSA valve 102 and the PSA valve 202 are opened and closed alternately. When the PSA nitrogen generator 101 desorbs, the PSA valve 102 is opened and the PSA valve 202 is closed; when the PSA nitrogen generator 201 desorbs, the PSA valve 202 is opened and the PSA valve 102 is closed.

[0042] In one embodiment, a one-way valve 302 is provided on the regeneration exhaust recovery main pipe 301 on the outlet side of the buffer tank. The one-way valve 302 is directed from the buffer tank to the dehumidifier return air pipe, and the one-way valve is provided to prevent the dehumidifier return air from blowing back into the buffer tank.

[0043] In one embodiment, a regeneration exhaust recovery main pipe valve 303 is provided before the dehumidifier enters the regeneration exhaust recovery main pipe 301 at the rear end of the one-way valve 302. This valve is normally open and closes when the equipment is under maintenance or the system is disconnected, which facilitates the maintenance of the dehumidifier or pressure swing adsorption nitrogen generator.

[0044] In one embodiment, a flow meter 306 is installed before the regeneration exhaust recovery main pipe 301 at the rear end of the regeneration exhaust recovery main pipe valve 303 and before it enters the dehumidifier. The flow data measured by the flow meter 306 is fed back to the dehumidifier central control system. The air intake volume of the dehumidifier fresh air duct 403 is adjusted according to the flow data so that the sum of the air intake volume of the dehumidifier fresh air duct 403 and the flow data measured by the flow meter 306 is equal to the fresh air volume calculated by the dehumidifier.

[0045] In one embodiment, a normally closed maintenance valve 305 is provided on the buffer tank 304, which is opened only when the dehumidifier is stopped but the pressure swing adsorption nitrogen generator is not stopped. When the system is disconnected and the nitrogen generator needs to work independently, the regeneration exhaust recovery main valve 303 is closed and the normally closed maintenance valve 305 is opened to maintain the normal operation of the nitrogen generator.

[0046] In one embodiment, in order to reduce the vibration of the buffer tank 304 caused by uneven exhaust gas flow, the buffer tank 304 should be installed on the ground and fixed with a steel frame. At the same time, the wall thickness of the buffer tank 304 should be greater than 5mm to reduce the vibration of the tank wall.

[0047] The present invention has been described in detail above. The above description is only one preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. Various simple modifications to the technical solutions of the embodiments of the present invention should still be included within the scope of the present invention.

Claims

1. A system for recovering and utilizing exhaust gas from a pressure swing adsorption (PSA) nitrogen generator, characterized in that, The device includes a pressure swing adsorption (PSA) nitrogen generator, wherein a branch pipe is installed at the end of the exhaust port of the PSA nitrogen generator, and the branch pipe is connected to the return air duct of the dehumidifier.

2. The pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 1, characterized in that, The system includes at least two pressure swing adsorption nitrogen generators, and a branch pipe is installed at the end of the exhaust port of each pressure swing adsorption nitrogen generator. The branch pipes are combined and connected to the dehumidifier return air duct. After desorption, the exhaust gas from the pressure swing adsorption nitrogen generator enters the dehumidifier return air duct and is treated together with the workshop return air. The mixed fresh air is then sent to the workshop through the dehumidifier supply air duct.

3. The pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 2, characterized in that, The system also includes a regenerated exhaust gas recovery main pipe and a buffer tank; the branch pipes converge at the regenerated exhaust gas recovery main pipe and are connected to the inlet side of the buffer tank, and the outlet side of the buffer tank is connected to the dehumidifier return air duct through the regenerated exhaust gas recovery main pipe.

4. The pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 2, characterized in that, A valve is also installed on the branch pipe at the end of the exhaust port of each of the aforementioned pressure swing adsorption nitrogen generators. The valves are opened and closed alternately to enable the pressure swing adsorption nitrogen generator to work alternately, using compressed air with a pressure dew point temperature below -70℃ as the feedstock to produce nitrogen.

5. A pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 3, characterized in that, A one-way valve is installed on the regeneration exhaust recovery main pipe on the outlet side of the buffer tank, and the direction of the one-way valve is from the buffer tank to the dehumidifier return air pipe.

6. The pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 5, characterized in that, A regeneration exhaust gas recovery main valve is installed before the dehumidifier enters the regeneration exhaust gas recovery main pipe at the rear end of the one-way valve. The main valve for regenerated exhaust gas recovery is normally open and closes when the equipment is under maintenance or the system is disconnected.

7. A pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 6, characterized in that, A flow meter is installed at the rear end of the regenerated exhaust gas recovery main valve before the regenerated exhaust gas recovery main pipe enters the dehumidifier; The flow meter is used to detect the flow rate before it enters the dehumidifier and feeds the flow data back to the dehumidifier's central control system.

8. The pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 3, characterized in that, The buffer tank is equipped with a normally closed maintenance valve, which is only opened when the dehumidifier stops but the pressure swing adsorption nitrogen generator continues to run.

9. A pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 3, characterized in that, The buffer tank is installed on the ground and fixed with a steel frame.

10. A pressure swing adsorption nitrogen generator regeneration exhaust gas recovery and utilization system according to claim 9, characterized in that, The wall thickness of the buffer container is greater than 5 mm.

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