JPS61178405A - Method of regenerating adsorbent for nitrogen generator - Google Patents

Abstract

PURPOSE:In separating and collecting N2 by sending compressed air to two adsorption tanks alternately so that O2 is generated in an adsorbent in the adsorption tanks, to regenerate the adsorbent without requiring an exclusive vacuum pump, by using negative pressure produced in an air compressor. CONSTITUTION:Air passed through the filter 5 is compressed by the compressor 1, sent through the aftercooler 2 and the drain separator 3 to the first adsorption tank 4A, O2 in the air is adsorbed on an adsorbent in it, and high-purity N2 is stored in the N2 product tank 12. In the operation, negative pressure in a cylinder in the compressor 1 is stored through the back-flow valve 18 and the solenoid valve 19 in the vacuum tank 20. After the adsorbent in the first adsorption tank 4A adsorbs O2 sufficiently, feed of compressed air is changed into the second adsorption tank 4B. Simultaneously the solenoid valve 8 of a pipe to connect the first adsorption tank 4A to the vacuum tank 20 is opened, the first adsorption tank is evacuated, O2 adsorbed on the adsorbent is released into the air, the adsorbent is regenerated, and used from the next O2 adsorption.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention involves supplying a fluid to be treated alternately to two adsorption tanks, and adjusting the pressure to perform adsorption treatment with an adsorbent in one tank and regenerate the adsorbent in the other tank. This invention relates to an adsorbent regeneration method related to the swing method.

[Background of the invention]

The conventional technology of a nitrogen generator will be explained with reference to FIG.

In Figure 1, 1 is a compressor, 2 is an aftercooler, and 3 is a compressor.
is a drain separator, and 4A and 4B are a first adsorption tank and a second adsorption tank.

The compressor 1 sucks atmospheric air through a filter 5, and the air compressed by the compressor removes moisture through an aftercooler 2 and a drain separator 3 before being supplied to an adsorption tank. This process will be explained below. First, among the solenoid valves 6, 7 and 8 of the first adsorption tank 4A, the solenoid valves 6 and 7 are opened and the solenoid valve 8 is closed. -Power cylinder 2 adsorption tank 4
Among the solenoid valves 9, 10 and 11 of B, solenoid valves 9 and 1
0: is closed and the solenoid valve 11 is open. When compressed air is supplied in this state, the compressed air is supplied to the first adsorption tank 4A via the solenoid valve 6, the oxygen gas in the compressed air is adsorbed by the adsorbent in the adsorption tank, and the remaining nitrogen gas is passed through the solenoid valve 7. The processed product is stored in the product tank 12.

On the other hand, the second adsorption tank 4B is evacuated by the vacuum pump 13, and the oxygen gas adsorbed by the adsorbent in the adsorption tank is released to the atmosphere 14 via the solenoid valve 11, so that the adsorption agent is regenerated as a result. That will happen.

By alternately repeating the process described above, nitrogen gas can be continuously generated.

In addition, 15 shown in FIG. 1 is a nitrogen concentration detector. If some trouble occurs in the process shown above and oxygen gas remains, this detector 15 closes the valve 16 and releases the gas to the product tank 12. This is to stop the gas supply. Also, the part indicated by the dotted line in the figure is the compressor 1. Cooling water supplied to the aftercooler 2 and the vacuum pump 13 is shown.

Such conventional devices require a vacuum pump, resulting in a complicated configuration, troublesome control, and high cost.

[Object of the Invention] An object of the present invention is to enable regeneration of an adsorbent by a pressure swing method without using a vacuum pump.

[Summary of the invention]

Nitrogen generators obtain compressed air using a compressor, which is then
Nitrogen gas is alternately supplied to an adsorption tank in a tank, and the adsorbent in the adsorption tank adsorbs oxygen gas to extract nitrogen gas, but the compressor generates negative pressure in the process of sucking air. The load is stored in a vacuum tank via a check valve, thereby regenerating the adsorbent.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

In this figure, the same reference numerals as in FIG. 1 indicate the same parts.

The compressor 1 has a piston 1a in a cylinder, and a suction valve 1b and a discharge valve 1c are attached to one end of the cylinder. In this configuration, when the piston 1a is reciprocated once, the pressure inside the cylinder will be.

In Figure 3, which shows pressure changes as shown in Figure 3,
P4 is the discharge pressure, P is the suction pressure (atmospheric pressure), but in the suction stroke of the compressor, the suction pressure P is shown by hatching.
, a lower pressure will occur. This is filter 5. Suction pipe line 17. This is due to the flow path resistance of the suction valve 1b, and it is well known that this pressure is normally 0.2 to 0.3 kg/cd.

The present invention utilizes the negative pressure generated within this cylinder to regenerate the adsorbent.

That is, in FIG. 2, the negative pressure in the cylinder of the compressor 1 is connected to the vacuum chamber 20 through the check valve 18 and the solenoid valve 19 so that it is stored in the vacuum chamber 20. Solenoid valve 2 for releasing gas to the atmosphere
1 and 22 are installed.

On the other hand, new solenoid valves 23 and 24 are installed in the first adsorption tank 4A and the second adsorption tank 4B to release compressed air to the atmosphere.
Install. Then, the solenoid valve 8 of the first adsorption tank 4A and the solenoid valve of the second adsorption tank 4B are connected to the vacuum tank 20, respectively.

In this configuration, to explain the process as a nitrogen generator, first, in order to supply compressed air only to the first adsorption tank 4A, the solenoid valve of the first adsorption tank 4A is opened to 6° 7 degrees,
The solenoid valves 8 and 23 are kept closed (at this time, the solenoid valves 9, 10, 11, and 24 of the second adsorption tank 4B are all closed, and the solenoid valves 21 and 24 attached to the vacuum chamber 20 are closed).
2 is also closed), and when compressor 1 is operated in this state, the compressed air flows to aftercooler 2. Oxygen gas is supplied to the first adsorption tank 4A via the drain separator 3, and oxygen gas is adsorbed by the adsorbent in the first adsorption tank 4A, and only nitrogen gas is supplied to the solenoid valve 7.
The product is stored in the product tank 12 via. On the other hand, the negative pressure generated within the cylinder is stored in the vacuum tank via the check valve 18 and the electromagnetic valve 19. When the adsorbent in the first adsorption tank 4A has adsorbed enough oxygen gas (saturated state), first,
At the same time as the solenoid valves 6 and 7 are closed, the solenoid valve 9.10 of the second adsorption tank 4B is opened to transfer the adsorption work to the second adsorption tank 4B.

During this time, the oxygen gas adsorbed on the adsorbent in the first adsorption tank 4A is taken out and the adsorbent is regenerated.In the first step, the solenoid valve 23 is opened and the residual compressed air in the first adsorption tank 4A is removed. Immediately after releasing the gas into the atmosphere, the solenoid valve 23 is returned to the closed state. In the second step, the solenoid valve 8 is opened and connected to the vacuum tank 20 to create a vacuum inside the first adsorption tank, and the adsorbent absorbs the adsorbent. After releasing the oxygen gas and regenerating the adsorbent, the solenoid valve 8 is returned to the closed state.
Since the oxygen concentration in the vacuum chamber 20 is high, there will be a problem if the compressor 1 sucks it in. Therefore, in the next third stage, a solenoid valve 2 attached to the vacuum chamber 20 is used to lower the oxygen concentration in the vacuum chamber 20.
1.22 is opened to release a part of the compressed air to the atmosphere, and then the solenoid valves 21 and 22 are closed, and at the same time, the solenoid valve 19 is opened to make the vacuum chamber 20 vacuum again.

The process explained above is carried out in the first adsorption tank 4A and the second adsorption tank 4A.
By alternately performing the steps B, nitrogen gas can be supplied continuously, and the adsorbent can be regenerated without using a separate vacuum pump as in the past.

Although the compressor 1 in FIG. 2 is shown as an example of a reciprocating compressor, the present invention is not limited to this, and may be applied to other rotary compressors (screw type, rotary type, etc.)
However, since negative pressure is generated due to suction resistance, it goes without saying that the same method can be used.

Also, as a result of eliminating the need for a vacuum pump, (1) The power consumption of the device is reduced. (2) The equipment space can be reduced. (3) The cost of the device can be reduced.

(4) Maintenance can be simplified. There are effects such as

〔Effect of the invention〕

As described above, according to the present invention, the vacuum pump can be abolished.

[Brief explanation of drawings]

FIG. 1 is a system diagram of a device to explain the prior art, the second diagram is a system diagram of a device to explain the present invention, and FIG. 3 is a PV diagram. 1...Compressor, 2...Aftercooler, 4A...
・First adsorption tank, 4B...Second adsorption agent, 6, 7, 8, 9
゜10.11, 19, 21, 22, 23.24... Solenoid valve, 18... Check valve, 20... Vacuum chamber.

Claims (1)

[Claims] In a nitrogen generator, a compressor alternately supplies compressed air to two adsorption tanks, the adsorbent in the adsorption tank adsorbs oxygen gas in the air, and extracts only nitrogen gas. Adsorbent regeneration characterized by storing the generated negative pressure in a vacuum chamber via a check valve, and using this negative pressure to release oxygen gas adsorbed on the adsorbent to the atmosphere to regenerate the adsorbent. Method.