TWM623594U - Pressure swing adsorption gas back flush system - Google Patents

Abstract

A pressure swing adsorption gas backflush system, comprising: a pressure swing adsorption device; a polymer membrane filter device, which is fluidly connected to the pressure swing adsorption device; and a gas backflush pipeline, which is connected to the pressure swing adsorption device. It is fluidly connected with the polymer membrane filtration device, and is used for backflushing the nitrogen gas separated after being filtered by the polymer membrane filtration device to the pressure swing adsorption device.

Description

PSA gas backflush system

This new model relates to a pressure swing adsorption gas backflush system, especially a pressure swing adsorption gas backflush system for backflushing the nitrogen separated after filtration to the pressure swing adsorption device.

The inside of the pressure swing adsorption device in the traditional pressure swing adsorption system will be filled with molecular sieve, and the surface of the molecular sieve will have many molecular pores (pores). When the pressure rises, the gas molecules will be forced into the molecular pores. Smaller gases are unaffected and can shuttle freely between molecular voids. After the pressure has dropped, the gas with larger molecules will remain in the molecular pores, and there are traditionally three methods to expel it at this time: 1. Use part of the gas purified by the pressure swing adsorption system for purging to sweep out the gas with larger molecules from the pores. 2. Evacuate the front end to suck out the gas with larger molecules remaining in the molecular pores. 3. Heating causes the gas to escape from the molecular pores by itself due to vibrations generated by absorbing energy. This method usually needs to be purged with clean gas.

In addition to energy-consuming heating, these three methods also need to consume part of the gas purified by the pressure swing adsorption system for purging, which will reduce the recovery efficiency. As shown in FIG. 1 , a pressure swing adsorption system 10 is proposed in the prior art, which includes: a pressure swing adsorption device 11 ; a gas backflushing pipe 13 , which is fluidly connected to the pressure swing adsorption device 11 and used to Part of the gas processed by the pressure swing adsorption device 11 is backflushed to the pressure swing adsorption device 11; and a polymer membrane filter device 12, which is fluidly connected to the pressure swing adsorption device 11 (flow rate shown in FIG. 1 ). The unit SLPM is standard liter per minute. Wherein, the polymer membrane filter device 12 is suitable for filtering the gas processed by the pressure swing adsorption device 12 to separate hydrogen and nitrogen in the gas, thereby recovering the hydrogen in the gas. However, this system uses clean gas after pressure swing adsorption for purging. Although this method can desorb the molecular sieve in the pressure swing adsorption device 11, it has the disadvantage of greatly reducing the hydrogen recovery efficiency.

As mentioned above, the conventional pressure swing adsorption system has the disadvantage of greatly reducing the hydrogen recovery efficiency. Therefore, it is necessary to provide a novel system to improve the hydrogen recovery efficiency.

In view of the above-mentioned deficiencies of the prior art, the present invention provides a pressure swing adsorption gas backflushing system to improve the hydrogen recovery efficiency.

One of the main technical means adopted to achieve the above-mentioned purpose is to make the aforementioned PSA gas backflush system, including: a pressure swing adsorption device; a polymer membrane filter device in fluid connection with the pressure swing adsorption device; and A gas backflushing pipeline is fluidly connected with the pressure swing adsorption device and the polymer membrane filter device, and is used for backflushing the nitrogen gas separated after being filtered by the polymer membrane filter device to the pressure swing adsorption device.

Compared with the traditional pressure swing adsorption system, the new pressure swing adsorption gas backflushing system has better hydrogen recovery efficiency.

The following describes the implementation of the present invention by means of specific embodiments, and those skilled in the art can understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied by other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit of the present invention.

"Fluidically connected" as used herein includes both direct "fluidic connection" and indirect "fluidic connection", for example, A device and B device "fluidically connected" may include: A device and B device are directly "fluidically connected"; and The A device and the B device are indirectly "fluidly connected" through a C device.

Example 1

As shown in FIG. 2 , the pressure swing adsorption gas backflushing system 20 of Embodiment 1 includes: a pressure swing adsorption device 21 ; a polymer membrane filter device 22 , which is fluidly connected to the pressure swing adsorption device 21 ; and a The gas backflushing pipeline 23 is fluidly connected with the pressure swing adsorption device 21 and the polymer membrane filter device 22, and is used for backflushing the nitrogen gas separated after being filtered by the polymer membrane filter device 22 to the pressure swing Adsorption device 21 . Wherein, the flow unit SLPM shown in FIG. 2 is standard liter per minute (standard liter per minute). It should be understood that the flow rate shown in FIG. 2 is only an example, the present invention is not limited to this, and the present invention belongs to the technical field Those with general knowledge can adjust the flow to appropriate flow according to actual needs.

Among them, the pressure swing adsorption device 21 is suitable for filtering a gas to adsorb a large amount of impurities in the gas.

The polymer membrane filtering device 22 is suitable for filtering the gas processed by the pressure swing adsorption device 21 to separate hydrogen and nitrogen in the gas, thereby recovering the hydrogen in the gas.

Wherein, the gas backflushing pipeline 23 is suitable for purging the molecular sieves in the pressure swing adsorption device 21 with the nitrogen gas separated after being filtered by the polymer membrane filter device 22 .

1, the pressure swing adsorption gas backflushing system 20 of Example 1 uses the nitrogen gas separated after being filtered by the polymer membrane filter device 22 to purge the molecular sieve in the pressure swing adsorption device 21. The pressure swing adsorption system 10 shown in 1 has at least the following two excellent technical effects: 1. The flow rate of the purged gas can be increased from the original 80SLPM to 120SLPM, which can reduce the purge time and increase the adsorption frequency. 2. Because the purging gas is changed from the original mixed gas to the nitrogen separated after being filtered by the polymer membrane filter device 22, the waste of hydrogen can be reduced, and the recovery efficiency of hydrogen can be increased from the original 42% to 70%.

Example 2

As shown in FIG. 3 , the pressure swing adsorption gas backflushing system 30 of the second embodiment includes: a pressure swing adsorption device 31 ; a polymer membrane filter device 32 , which is fluidly connected to the pressure swing adsorption device 31 ; and a The gas backflushing pipeline 33 is fluidly connected with the pressure swing adsorption device 31 and the polymer membrane filter device 32 and is used for backflushing the nitrogen gas separated after being filtered by the polymer membrane filter device 32 to the pressure swing Adsorption device 31 .

The pressure swing adsorption device 31 , the polymer membrane filter device 32 and the gas backflushing pipeline 33 in the second embodiment are the same as those in the first embodiment, and will not be repeated here.

Compared with Embodiment 1, the pressure swing adsorption gas backflushing system 30 of Embodiment 2 further includes: a purification device 34, which is fluidly connected to the pressure swing adsorption device 31 and the polymer membrane filter device 32, and is To further remove moisture and impurities in the gas processed by the pressure swing adsorption device 31 . The arrangement of the purification device 34 can prevent the water vapor and impurities in the gas processed by the PSA device 31 from poisoning the polymer membrane in the polymer membrane filter device 32 , so as to improve the stability of the PSA gas backflushing system 30 . For example, the purification device 34 may include a desiccant for adsorbing moisture and activated carbon for adsorbing impurities, but the present invention is not limited thereto.

Example 3

As shown in FIG. 4 , the pressure swing adsorption gas backflushing method of Embodiment 3 includes: (a) filtering a gas through a pressure swing adsorption device to remove impurities S101 in the gas; (b) passing through a polymer Membrane filtration of the gas treated in step (a) to separate hydrogen and nitrogen S102 in the gas; and (c) backflushing the nitrogen separated in step (b) to the pressure swing adsorption device to purge the variable Molecular sieve S103 in the pressure adsorption device.

Wherein, in step (a), a gas can be filtered through the pressure swing adsorption device as described in Example 1 and Example 2.

Wherein, in step (b), the gas treated in step (a) can be filtered through the polymer membrane filtration device described in Example 1 and Example 2.

Wherein, in step (c), the nitrogen gas separated by step (b) can be backflushed to the pressure swing adsorption device through the gas backflushing pipeline as described in Example 1 and Example 2.

In one embodiment, the pressure swing adsorption gas backflushing method of Example 3 may further include: (b-0) Before filtering the gas processed in step (a) through a polymer membrane, further passing through a purification device to The gas treated in step (a) is purified to further remove moisture and impurities in the gas treated by the pressure swing adsorption device, thereby avoiding high poisoning of the moisture and impurities in the gas treated by the pressure swing adsorption device. Molecular membrane to improve the stability of the PSA gas backflush method.

The purpose of the new pressure swing adsorption gas backflushing system is to remove impurities such as ammonia and water in the gas, and also to remove nitrogen and recover hydrogen. Since the pressure swing adsorption device needs to be purged and regenerated, only using the pressure swing adsorption device to remove three gases such as ammonia, water and nitrogen will lead to a large loss of hydrogen. Therefore, the new pressure swing adsorption gas backflushing system first uses a pressure swing adsorption device to remove two gases such as ammonia and water, then uses a polymer membrane to remove nitrogen, and then uses the nitrogen separated by the polymer membrane to purge Molecular sieves in the pressure swing adsorption device. The new PSA gas backflushing system can increase the hydrogen recovery rate from 42% to 70% by the above-mentioned technical means.

The above-mentioned embodiments are only illustrative of the present invention, but are not intended to limit the present invention. Any person skilled in the art can modify and change the above embodiments without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the rights of this new model should be as set out in the scope of the patent application described later.

10: Pressure swing adsorption system 11: Pressure swing adsorption device 12: Polymer membrane filtration device 13: Gas backflush pipeline 20: PSA gas backflush system 21: Pressure swing adsorption device 22: Polymer membrane filtration device 23: Gas backflush pipeline 30: PSA gas backflush system 31: Pressure swing adsorption device 32: Polymer membrane filtration device 33: Gas backflush pipeline 34: Purification device S101: Steps S102: Steps S103: Steps

[Fig. 1] is a schematic diagram of a conventional pressure swing adsorption system. FIG. 2 is a schematic diagram of the pressure swing adsorption gas backflushing system of Example 1. FIG. [FIG. 3] is a schematic diagram of the PSA gas backflushing system of Example 2. [FIG. [Fig. 4] is a flow chart of the hydrogen purification method of Example 3. [Fig.

20: PSA gas backflush system

21: Pressure swing adsorption device

22: Polymer membrane filtration device

23: Gas backflush pipeline

Claims (2)

A pressure swing adsorption gas backflush system, comprising: a pressure swing adsorption device; a polymer membrane filter device in fluid connection with the pressure swing adsorption device; and A gas backflushing pipeline is fluidly connected with the pressure swing adsorption device and the polymer membrane filter device, and is used for backflushing the nitrogen gas separated after being filtered by the polymer membrane filter device to the pressure swing adsorption device. The pressure swing adsorption gas backflush system of claim 1, further comprising: A purification device is fluidly connected with the pressure swing adsorption device and the polymer membrane filter device, and is used for further removing moisture and impurities in the gas processed by the pressure swing adsorption device.

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