JP2001314726A - Gas separation/recovery/charging unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a unit for gas separation/recovery/charging in which, when gaseous SF6 and a gaseous diluent other than SF6 in a gas holding vessel 26 are recovered, even if unseparated gaseous SF6 remains in the separated gaseous diluent in a certain concentration or higher in a stage for separating the gaseous SF6 and the gaseous diluent from each other in a gas separation section 21, the unseparated gaseous SF6 can be prevented from diffusion into the atmosphered. SOLUTION: In the stage for separating gaseous SF6 and the gaseous diluent from each other in the gas separation section 21, a discharged gas consisting of the separated gaseous diluent in which a minute amount of gaseous SF6 coexists as a contaminant is recycled to the gas holding vessel 26 through a discharged gas outlet 2 of the gas separation section 21 and a discharged gas inlet 2' of the gas holding vessel 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating gas for electric power equipment as SF6 gas (sulfur hexafluoride gas, hereinafter the same).
Or a mixed gas of SF6 gas and a diluent gas. The power device is inspected and repaired by extracting and recovering the SF6 gas and a diluent gas for dilution, or after the inspection and repair is completed. Refilling technology.

[0002]

2. Description of the Related Art SF6 gas is filled in a transformer for high voltage power in a substation or the like, or in a circuit breaker of a power circuit, and is miniaturized by utilizing its thermal stability, electrical stability, and high withstand voltage. And the contribution is significant by reducing the volume of substations in urban areas. The SF6 gas filled in a transformer or a circuit breaker has a purity of 100% or a gas diluted appropriately with a diluent gas such as nitrogen gas.

[0003] The equipment in which these are used requires periodic inspection and maintenance and repairs. In the case of inspection and maintenance and repairs, these gases are extracted and replaced with the atmosphere, and then people enter. Inspect and repair the inside of the equipment. When the inspection and repair are completed, the insulating gas is filled again and the operation starts.
At the time of gas removal, vacuum recovery is performed until a high vacuum is obtained so that SF6 gas does not remain in the equipment, and at the time of this filling, air is discharged to a high vacuum so that air does not remain in a container such as a power equipment. In addition, it is necessary to fill the insulating gas with a predetermined concentration. This required a long time. Conventionally, when extracting gas, these gases are released into the atmosphere because they cause little harm to the human body and the like.

However, since SF6 gas is an expensive gas, there has been a recovery device in a range in which the gas can be easily recovered and reused cost-effectively. This SF6 gas is recovered, inspected and repaired, and refilled and refilled. Sometimes used. There was a device that pressurizes and compresses the extracted SF6 gas, cools it, cools it, and then liquefies it. There was no apparatus for separating and recovering only SF6 gas from the gas.

[0005] That is, SF6 is mixed with another diluent gas.
If the concentration of the gas is low, it is compressed to a high pressure because the partial pressure is low, and it is necessary to cool down to a lower temperature, so the price of the equipment is expensive, so such a thing is made. Did not.

In recent years, emission of carbon dioxide and the like into the atmosphere has been regulated to prevent global warming. 19
The 1997 World Environment Conference was held in Kyoto, and as a result, the emission of SF6 gas, which has a global warming potential 24,000 times that of carbon dioxide gas, into the atmosphere has been strictly regulated.
In order to prevent the SF6 gas from leaking into the atmosphere, (1) eliminate the gas leaking from the sealing portion of the filling device and leaking. (2) It is important to eliminate SF6 gas released into the atmosphere when extracting or refilling gas at the time of equipment installation, maintenance, repair, dismantling and disposal.

[0007] Regarding (1), the number is very small at present due to the improvement of the seal portion of the equipment. Regarding (2), the electric power industry decided by the Electric Power Joint Research Group in December 1998 on the “Standards for Handling SF6 Gas for Electric Power”.
Was voluntarily regulated and its emission was regulated. The main content of the regulation is 0.015 at the time of inspection and repair.
MPa · abs (recovery rate of 97 vol% or more) and 0.005 MPa · abs (recovery rate of 99 vol%) at the time of dismantling
Voluntary standards for suctioning and recovering to the high vacuum region described above were created. The power industry has a public mission to minimize power outages associated with service and repair.

There is a drawback in that if the material is sucked and collected up to a high vacuum region, it takes a long time to collect. The low recovery rate at the time of inspection and repair is a compromise value for minimizing the power outage time due to the stoppage of the device, and a sufficient time is taken for evacuation at the time of removal. That is, the liquid is sucked and collected up to a high vacuum region, and the amount of leakage into the atmosphere is reduced.

The electric power industry will develop and implement a recovery device that meets the above standards by 2005.
Even when 50 vol% of nitrogen gas, which is an inert gas, is mixed, the impulse breakdown voltage is 85% of SF6 gas alone and the breakdown voltage of commercial power frequency is 96.6%. The number of manufacturers that use a diluent gas such as nitrogen gas when sealing them in a circuit breaker is increasing.

Conventionally, since a mixed gas containing such a diluent gas has been difficult to recover, most of the mixed gas has been discharged to the atmosphere and discarded during inspection and disposal. Furthermore,
After the completion of the inspection and maintenance work and the repair work, the SF6 gas is refilled. In order to keep the SF6 gas in the collection container at a predetermined concentration, suction is performed to a high vacuum area so that no outside air remains in the collection container. After the outside air is once exhausted, SF
It took a long time to refill the six gases. It is an object of the present invention to provide a gas separation, collection and filling apparatus for separating and collecting this gas, and further performing refilling.

[0011]

The object of the present invention is to recover almost all of SF6 gas and diluent gas from a container to be recovered (transformer, circuit breaker, etc.) without leaking into the atmosphere, and further includes recovery and refilling. The purpose is to reduce the time required for inspection work. At the time of periodic inspections and repairs, after extracting the gas to be recovered from the container to be recovered, such as a transformer charged with insulating gas, and replacing the inside of the container with air, a person enters to repair and inspect the power equipment. After the repair is completed,
The insulating gas is filled again. During these times, a power outage occurs because the operation of the power equipment is stopped. In order to shorten the power outage time, the time required for repair and inspection of equipment and devices in the container to be recovered requires a predetermined time regardless of the performance of the gas recovery and refilling device. It is necessary to shorten the time for extracting and recovering the gas other than the predetermined time and reducing the time for refilling the gas, and the present invention seeks to shorten the time by a new method relating to the recovery and refilling.

[0012]

In order to solve the above-mentioned problems, the present invention has a critical temperature of 45.64 ° C. and a critical pressure of 3.6.
6MPa · G, melting point -50.8 ° C, sublimation point -63.8 ° C
In which the characteristics of SF6 gas are taken into account. FIG. 1 shows an embodiment of the present invention.

The to-be-recovered container 26 is filled with a to-be-recovered gas such as SF6 gas at a high pressure of about 0.6 MPa · G.
Since the SF6 gas is an easily liquefied gas, a pressurizing unit 22 for pressurizing the SF6 gas by a pressurizing pump 31 and a liquefying unit 23 for cooling and liquefying the gas are provided. In a range where the concentration of the SF6 gas in the gas to be recovered is high, Since the partial pressure of SF6 gas in the gas to be recovered is also high, the pressure required for easy liquefaction may be in a relatively low pressure range from the relationship between the liquefaction temperature and the pressure of the gas to be liquefied, and the liquefaction temperature may also be low. It can be easily liquefied and recovered even in a relatively high range.

First, the SF6 gas is recovered by the above-described method until the pressure in the container to be recovered reaches a liquefiable range by the pressurizing pump 31 and the liquefying unit 23. When the pressure becomes equal to or lower than a predetermined pressure, a diluted gas such as nitrogen gas is introduced from an external gas supply unit 25 into the container to be recovered to dilute the SF6 gas, and the recovered gas obtained by mixing the diluted gas and the SF6 gas is removed. The diluted gas and SF6 are introduced from the container to be collected into the gas separation section.
It is intended to recover SF6 gas by separating it into gas.

The gas to be collected filled in the container to be collected may be diluted with a gas containing 100% SF6 gas and a diluent gas such as nitrogen gas as described above.
By providing the gas separation unit 21 for separating the SF6 gas from the mixed gas of the dilution gas and the SF6 gas, instead of evacuating to a high vacuum and taking out the gas to be recovered, the gas to be diluted is filled and the inside of the container to be recovered is filled. This method, in which the concentration of SF6 gas is reduced while the concentration is positive, is taken out and separated and collected, the collection time is shorter.

The gas separation section is provided with a PSA method (Pressure Swing) using an adsorbent for adsorbing a specific gas.
Adsorption). When a mixed gas containing the specific gas and the diluent gas is sent to the adsorption column filled with the adsorbent while applying pressure, the specific gas (one gas) is adsorbed and removed by the adsorbent, and the other gas that is not adsorbed is removed. Since this is separated and taken out from the other end of the adsorption cylinder, this step is called an adsorption step, and the pressure at which gas is sent while applying pressure to this adsorption cylinder is called an operating pressure.

Shortly before the specific gas is adsorbed by the adsorbent and becomes full, the supply of the mixed gas (raw material gas) is stopped, and the pressure of the adsorber is reduced from the inlet end of the adsorber. Since the specific gas adsorbed on the adsorbent is released from the adsorbent and discharged, and the adsorbent's adsorption ability is regenerated, this step is called a regenerating step.

Since the gas is separated while repeating the adsorption step and the regeneration step, that is, while applying or decreasing the pressure to the adsorption column, it is called a pressure fluctuation adsorption (PSA) method.

The adsorbent adsorbs SF6 gas, which is a target gas, and does not adsorb nitrogen gas, which is a diluting gas, depending on the type of adsorbent. Conversely, adsorbent mixes SF6 gas, which is a target gas, without adsorbing it. Some adsorb diluent gas better. The method of extracting the target gas differs slightly depending on the adsorbent used. For example, when SF6 gas is used as a target gas, the former adsorbent includes molecular sieve charcoal in which activated carbon has a molecular sieve function, and the latter adsorbent includes zeolite 5A type and 4A type. The zeolite also adsorbs nitrogen gas, moisture, carbon dioxide gas, oxygen, and a part of the decomposition gas of SF6, so that these can be separated from the mixed gas.

In the former case, since the SF6 gas is separated by being adsorbed on the adsorbent, the SF6 gas released from the adsorbent in the pressure reduction regeneration step is recovered. In the latter case, the SF6 gas is separated from the other end of the adsorption cylinder and comes out in the pressure adsorption step, so that the SF6 gas is recovered in the adsorption step. Select an appropriate one of these two adsorbents and
The present invention constitutes an SA type gas separation / recovery / filling apparatus, and the present invention includes a method using both of these adsorbents.

The gas separation unit having such a configuration allows the
Even if it is separated into 6 gases and another diluent gas, the SF6 gas is included on the diluent gas side, albeit slightly. It is technically difficult to suppress the amount of SF6 gas contained in the separated diluted gas to the order of ppm over the entire range in which the concentration of SF6 gas in the gas to be recovered changes. It is problematic to release the exhaust gas contained in the air into the atmosphere.

For this reason, the diluent gas separated by the gas separation section containing a small amount of SF6 gas is returned to the container to be recovered, instead of being released into the atmosphere. That is, the container to be recovered and the gas separation unit are connected by a conduit, and the gas to be recovered in which a plurality of types of gases are mixed in the container to be recovered is separated by the gas separation unit, and one of the separated gases is recovered. At the same time, a gas separation / recovery / filling device is configured in which the other diluent gas is returned to the above-mentioned container via a conduit and filled. The gas to be recovered is a mixed gas obtained by mixing the SF6 gas and the diluting gas. Further, one of the gases separated by the gas separation unit is SF6 gas, and the other gas is a diluting gas. Further, one of the gases separated by the gas separation unit is a diluent gas, and the other gas is an SF6 gas.

At the time of gas filling after the completion of the inspection work, one of the gases separated by the gas separating section is a diluting gas, which is recovered outside the container to be recovered or released into the atmosphere, and the other gas, SF6 gas, is recovered. Return to collection container. This will be described in more detail later. As described above, at the time of recovery, when the SF6 gas is recovered while cyclically circulating the gas through the route for returning the separation gas to the recovery container from the recovery container and the gas separation unit, the SF6 gas concentration in the recovery container is reduced. As the pressure decreases, the internal pressure of the container to be collected also decreases.
In order to compensate for this pressure, the gas is supplied from the gas supply unit 100 having the dilution gas supply source, and the gas is continuously separated by the gas separation unit 21 while maintaining a constant pressure.

When the concentration of the gas to be recovered falls below a certain value, SF6 contained in the diluent gas separated in the gas separation section is used.
The gas concentration is so low that it can be released to the atmosphere. The gas supply unit for supplying the dilution gas may be any gas that can be separated by the gas separation unit, and may be nitrogen gas or air (mixed gas of nitrogen and oxygen). If zeolite is used as the adsorbent, it can be sufficiently separated. . After extracting the insulating gas, it is replaced with air, and a person enters the inside to perform work (repair), which is convenient. The name of the container to collect this power equipment is good when collecting gas, but after inspection and repair, when filling gas again, it becomes a filling container, but it is not good that the name changes with the same product. In the text, even when gas is filled, it is referred to as a container to be collected.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS After the repair and inspection are performed, the SF after filling the gas is lower than the target concentration in the process after refilling the gas.
When the 6 gases are filled in the container to be recovered, the mixed gas in the container to be recovered is introduced into the gas separation section to be separated, and the diluted gas separated by returning the highly concentrated SF6 gas to the container to be recovered is used. Either recover and reduce the SF6 gas contained therein by further processing and discharge it to the atmosphere, or if the concentration of SF6 gas contained in the exhaust gas is a value below a certain level, an exhaust gas collection container By releasing the diluted gas into the atmosphere as it is without collecting the diluted gas into the container 63, it is possible to increase the concentration of SF6 gas by extracting excess diluted gas from the container to be collected.

By using this means, it is not necessary to evacuate the air in the container to a high vacuum at the time of refilling, and after evacuating the air to a certain value, diluting gas is injected first.
After the air is expelled by this, SF6 gas is charged, and the route between the gas separation section and the container to be recovered can be filled to discharge air and the like to the outside so that the filling time can be reduced. it can. More specifically, in a gas separation / recovery / filling device having a concentration sensor 20 for SF6 gas and a gas separation unit 21, a gas to be recovered including SF6 gas and another diluent gas is introduced into the gas separation unit from a recovery container 26, Separation into SF6 gas and other diluent gas
The gas is supplied to the pressurizing section 22 and the liquefying section 23 from the SF6 gas outlet 3.
And the liquid is collected and liquefied, and the dilution gas is returned to the collection container 26 by the pump 7. The concentration of the SF6 gas in the collection gas is measured by an SF6 gas concentration sensor 20.
The dilution gas is detected at a predetermined value or less.
Open 2 to release into the atmosphere.

In the gas separation / collection / filling apparatus having the gas separation unit 21, the pump 7, and the gas supply unit 25, the collection target gas including the SF 6 gas and other diluent gas is supplied to the gas separation unit 21 from the collection target container 26. Introduced and separated into SF6 gas and another diluent gas, the SF6 gas is recovered in the same manner as described above, and this diluent gas is returned into the container 26 to be recovered by the pump 7 and introduced into the gas separation unit 21 described above. When the pressure of the gas in the container to be recovered becomes lower than a predetermined pressure while being detected by the pressure sensor 36, the gas supply unit 2
From 5, the valve 29 is opened to introduce gas into the container to be collected and filled.

For example, when the operating pressure of the gas separation unit 21 is 0.2
In the case of MPa · G, the pressure at which gas is introduced from the gas supply unit 25 into the container 26 to be recovered and started to be filled is based on a pressure of 0.2 MPa · G or more. In this case, PSA gas separation is performed by supplying the PSA gas to the gas separation unit 21 at the pressure in the container to be recovered. The gas supplied from the gas supply unit 25 may be a diluting gas that can be separated by the gas separation unit 21.
7 and the pressure reducing valve 28 to supply nitrogen gas, or to supply air by a device that introduces outside air by an air pump 42 or a device that combines an air pump and a dryer 43. it can.

FIG. 3 shows another embodiment. The portion to be liquefied and recovered after the SF6 gas outlet 3 for taking out the concentrated SF6 gas is the same, so that the description is omitted. This is a method in which a gas to be recovered is provided from a container to be recovered, and a gas extracting section 66 is provided, and the gas to be recovered is supplied to the gas separation section through the gas extracting section. This is because the gas take-out part is composed of a pressure reducing valve 69, a pressure increasing pump 65, an electromagnetic valve and the like, and the pressure of the gas to be collected filled in the container to be collected 26 is higher than the operating pressure of the PSA type gas separation part. When high, pressure reducing valve 6
9 to adjust the pressure required for its operating pressure and supply;
When the recovery operation proceeds and the pressure in the collection container 26 falls below the above-described operation pressure, the pressure-increasing pump 65 is operated to extract the collection gas from the collection container 26 and perform the PSA.
Has the function of increasing the pressure up to the operation pressure required for the operation and supplying it.

In the case of the configuration having this gas take-out part, in the gas separation / recovery / filling apparatus having the gas take-out part 66 and the pump 7 in the gas separation part 21, the gas separation part makes the SF6 gas and other diluent gas A gas in which SF6 gas is partially mixed in the dilution gas is returned to the container to be recovered by the pump, and when the pressure of the gas in the container becomes lower than the atmospheric pressure, the valve is opened. 29 'is opened to open the outside air from the outside air intake port 70 into the container to be collected and fill it as dilution gas.

FIG. 1 is a flowchart showing the overall configuration of the present invention including the pressurizing section 22 and the liquefying section 23. The details of the gas separation unit 21 in FIG.
This flow chart applies here. The to-be-collected gas is connected to the to-be-collected gas inlet 1 of the gas separation unit 21 from the to-be-collected gas outlet 1 ′ of the to-be-collected container 26, and the SF6 gas concentrated in the gas separation unit 21 is pressurized from the SF6 gas outlet 3. The separated gas mainly containing the other diluting gas is returned from the exhaust gas outlet 2 to the exhaust gas inlet 2 ′ of the container 26 to be recovered. The pressurizing section 22 includes a buffer tank 30, a pressurizing pump 31, and a return circuit including a pressure reducing valve 32 so as not to overpressurize to a certain pressure or more. Pressurized SF6
The gas is sent to a liquefaction unit 23 and is stored in a storage tank 24 after being cooled and liquefied. The liquefaction unit 23 includes a cooler 33, a solenoid valve 3
The liquefaction tank 35 is cooled by a cooler 33 and sent to the liquefaction tank 35 to be cooled and liquefied.

The SF6 gas entering the liquefaction unit 23 temporarily stores SF6 gas in the liquefaction tank 35 unless the purity is 100%.
Since the gas is liquefied and taken out to the storage tank 24, it is necessary to take out the non-liquefied impure gas and make it upstream of the gas separation part, but the description of this configuration is omitted in FIG. As the SF6 gas is liquefied and taken out, the pressure in the recovery container decreases as the gas is liquefied and taken out. Therefore, the valve 29 is opened from the gas supply unit 25 to introduce and fill the gas, and the gas necessary for the operation of the gas separation unit 21 is filled. Configure to maintain pressure. For example, the gas supply unit 25 may include a nitrogen gas cylinder 27 and a pressure reducing valve 28. Also, as shown as a gas supply unit 40, after outside air is taken in from a filter 41 and pressurized by a compressor 42, the outside air from which moisture is removed by a dryer 43 is supplied as a dilution gas by connecting the outside air supply 44 and a valve 29 to the supply outside air. Good.

FIG. 2 shows a flow chart of the gas separation section 21.
FIG. 2A is a flow diagram of a gas separation unit that uses molecular sieve charcoal that strongly adsorbs SF6 gas, which is a target gas, onto an adsorbent and hardly adsorbs a diluent gas such as nitrogen gas. In this example, the gas from the container 26 to be recovered such as a transformer is introduced from the inlet 1 of the gas to be recovered, the solenoid valves 8 and 10 are opened, and the gas is introduced into the adsorption column 4 to adsorb the SF6 gas to the adsorbent. From the other end of the cylinder 4, nitrogen gas or the like as a diluting gas is separated and taken out from SF 6 gas, and stored in the exhaust gas tank 6 via the solenoid valves 14 and 9. The exhaust gas is discharged under pressure from the exhaust gas outlet 2 by the pump 7 and returned to the container 26 shown in FIG. The gas to be recovered introduced from the inlet 1 is a pressure sensor 36 and a SF6 gas concentration sensor 2
0 and pressure and concentration are measured.

The gas to be recovered is introduced into the adsorption column 4 and is stopped before the adsorbent becomes full (before the adsorption saturation) by adsorbing the SF6 gas. To perform a pressure equalization step. That is, the solenoid valves 8, 10, 1
6, 11, and 14 are closed, all the solenoid valves of the adsorption cylinder 5 are closed, and the equalizing electromagnetic valve 17 is opened to release nitrogen gas floating in the adsorption cylinder 4 toward the adsorption cylinder 5 in part of SF6. Move with gas.

After that, the solenoid valve 17 is closed, the SF6 gas adsorbed on the adsorbent of the adsorption cylinder 4 is opened, the solenoid valves 11 and 18 are opened, and the concentrated SF6 gas is discharged from the SF3 gas outlet 3 through FIG.
To the buffer tank 30 shown in FIG. In this step, the SF6 gas adsorbed on the adsorbent of the adsorption column 4 is desorbed by decompressing the inside of the adsorption column, concentrated and taken out from the outlet 3 of the SF6 gas, and the adsorption capacity of the adsorbent is regenerated. This is called the regeneration process.

The adsorption cylinder 5 introduces the gas to be recovered through the electromagnetic valve 12, adsorbs the SF 6 gas on the adsorbent, and
5 and 9 are opened, and nitrogen gas is sent to the exhaust gas tank 6, and is discharged through the exhaust gas outlet 2 by the pump 7 and returned to the container 26 shown in FIG. You. When the SF6 concentration in the gas to be recovered falls below a certain value by the SF6 gas concentration sensor, the concentration of SF6 in the separated diluent gas (nitrogen gas) becomes very low. Stop,
The valve 52 is opened and discharged from the discharge port 50 into the atmosphere.
When the pressure of the pressure sensor 36 becomes equal to or less than a predetermined value, a diluting gas or outside air is introduced from the gas supply unit into the container to be collected. According to this method, gas separation is performed in the gas separation section while repeating the pressure adsorption step, the pressure equalization step, and the regeneration step. Thus, gas separation is performed at the inlet 1 of the gas to be recovered.
Gas to be recovered as raw material gas from
SF6 adsorbed and separated by F6 gas and concentrated in the regeneration process
It is taken out as gas and sent out from the outlet 3 of SF6 gas. On the other hand, nitrogen gas or the like as a diluent gas is stored in the exhaust gas tank 6 and returned to the container 26 to be recovered by the pump 7.

FIG. 2 (B) shows a gas separation method using a zeolite, which adsorbs SF6 gas, which is a target gas, and adsorbs nitrogen gas, moisture, oxygen, etc., which is a diluent gas, as an adsorbent. It is a flowchart which shows the structure of a part.
The gas to be recovered as a raw material gas is introduced from the inlet 1 of the gas to be recovered, the solenoid valves 8 and 10 are opened and introduced into the adsorption cylinder 4, and the adsorbent adsorbs nitrogen gas or the like as a diluting gas. SF6 gas, which hardly adsorbs from water, is concentrated
The SF 6 gas is sent out from the outlet 3 of the SF 6 gas to the buffer tank 30 of FIG.

Shortly before the adsorbent of the adsorption column 4 becomes full (adsorbs saturated) by adsorbing nitrogen gas or the like as a diluent gas, the introduction of the raw material gas is stopped, and the adsorbent is brought into contact with the adsorption column 5 after the regeneration step. The pressure equalization process is performed. That is, the solenoid valves 8, 1
8, 11, 13 are closed and the solenoid valves 14, 15, 10, 1
2 is opened to move the SF6 gas floating in the adsorption cylinder 4 toward the adsorption cylinder 5 together with a part of the nitrogen gas, and then the solenoid valves 10, 14, 13 are closed, and the solenoid valves 11, 9, 8 , 1
The source gas is introduced into the adsorption cylinder 5 by opening 2, 15, 18 and the concentrated SF6 gas is led out from the SF6 gas outlet 3 through the solenoid valves 15, 18, so that the adsorption cylinder 5
Will enter the adsorption step.

Nitrogen gas or the like, which is a diluent gas adsorbed by the adsorbent of the adsorption cylinder 4, is reduced by reducing the pressure in the adsorption cylinder so that the adsorbed nitrogen gas or the like is released and the electromagnetic valve 1 is released.
After being stored in the exhaust gas tank 6 via the outlets 1 and 9, the valve 51 is opened by the pump 7 and sent out from the outlet 2 of the exhaust gas to the container 26 to be recovered in FIG. 1. Also in this case, the concentration and pressure of SF6 gas in the gas to be recovered taken in through the inlet 1 are measured by the SF6 gas densitometer 20 and the pressure sensor 36, and are separated after the concentration of SF6 gas in the gas to be recovered falls below a certain value. Since the concentration of SF6 contained in the diluted gas is very low, the valve 51 is closed and the valve 52 is opened to discharge to the atmosphere. As described above, the gas separation is continuously performed by repeating the adsorption step, the pressure equalization step, and the regeneration step.

It should be noted that the equalizing step in the description of the flow charts of FIGS. 2A and 2B can be omitted depending on the capacity of the apparatus. Next, FIG. 4 shows an example of filling. The description will be made using this. FIG. 2 shows a gas supply unit 100 capable of supplying SF6 gas and a diluent gas by an SF6 gas supply source 60 composed of an SF6 gas cylinder 55 and a pressure reducing valve 57, and a diluent gas supply source 61 composed of a nitrogen gas cylinder 56 and a pressure reducing valve 58. In the gas separation / collection / filling device having the pressure sensor 36 and the concentration sensor 20 in the gas separation unit 21, the collection target container 26 and the gas supply unit 100 are connected by a conduit, and the pressure sensor 36 and the concentration sensor 20 are connected.
The gas mixture in the container to be recovered is connected to the container via a conduit, and the pressure and concentration of the gas mixture are measured. Although not shown in the figure, the pressure sensor 36 and the concentration sensor 20 are connected to signal lines. The control unit is also connected to the gas supply unit via a signal line, which is also omitted in the figure, and is diluted from the gas supply unit 100 to the container 26 to be recovered by an instruction from the control unit. The gas and SF6 gas are controlled and introduced, and the diluted gas is introduced into the container 26 to be recovered by opening the valve 29 'according to the instruction of the control unit, and the outside air remaining in the container is recovered. After discharging a certain amount from the container 26, the SF
6 gas is introduced by opening the valve 29, and while detecting the pressure and concentration in the container to be recovered by the pressure sensor 36 and the concentration sensor 20, the SF6 gas is supplied from the gas supply unit so as to reach a predetermined filling pressure and concentration. And supply (fill) while controlling the dilution gas.

Next, another embodiment will be described. SF6 gas supply source 60 composed of gas separator 21, SF6 gas cylinder 55 and pressure reducing valve 57, nitrogen gas cylinder 27 and pressure reducing valve 2
8, a gas supply unit 100 capable of supplying SF6 gas and dilution gas by a dilution gas supply source 25, a pressure sensor 36 and a concentration sensor 2 in the gas separation unit 21 shown in FIG.
In the gas separation / collection / filling apparatus having a control unit, the collection container 26 and the gas supply unit 1 are omitted in FIG.
00 is connected by a conduit, and the mixed gas in the container to be recovered 26 is connected by a conduit to the gas separation unit 21, the pressure sensor 36, and the concentration sensor 20, and the pressure and concentration of the mixed gas are measured.
Although the control unit and signal lines are omitted in the figure,

The pressure sensor, the concentration sensor, and the control unit are connected by a signal line, the control unit, the gas separation unit, and the gas supply unit are connected, and the control unit, the gas separation unit, and the gas The supply unit is connected by a signal line, and SF6 gas and dilution gas are supplied from the gas supply unit to the valve 2 by the control unit.
9 ', the valve 29 is opened and closed to introduce the gas. First, the dilution gas is introduced into the collection container 26 by opening the valve 29', and the outside air remaining in the container is kept constant from the collection container 26. After discharging the amount, SF6 gas is introduced by opening the valve 29,
The mixed gas is introduced into the gas separation unit 21 while supplying the gas from the gas supply unit 100 so that the pressure and the concentration in the container to be recovered are set to a predetermined filling pressure and concentration while being detected by the pressure sensor 36 and the concentration sensor 20. To separate SF6 gas and diluent gas containing outside air,
The F6 gas outlet 3 and the exhaust gas inlet 2 'are connected and returned, and the dilution gas containing the outside air is opened by opening the valve 52 and the discharge port 50
It is configured to discharge more out of the container to be recovered, and is filled with SF6 gas while discharging air and the like remaining in the container to be recovered 26, thereby shortening the charging time.

[0043]

When the SF6 gas and another diluent gas (for example, nitrogen gas) are separated in the gas separation section by the PSA method, it is technically difficult to achieve 100% perfect separation. Even in this case, by implementing the present invention in which the separated diluted gas is returned to the container to be recovered, the mixed gas containing the diluted SF6 gas having the concentration equal to or higher than the predetermined concentration value is not released to the atmosphere. Since the gas can be collected, the gas to be collected in the container to be collected can be treated without causing air pollution.
Further, at the time of refilling, by discharging the separated and concentrated SF6 gas into a container such as a transformer and the diluent gas out of the container, air or the like can be discharged while filling.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an overall configuration of the present invention.

FIG. 2A and FIG. 2B both show a gas separation unit 21;
FIG. 3 is a flowchart showing a detailed configuration of FIG.

FIG. 3 is a flow chart showing an interconnection state between the container to be recovered 26, the gas take-out unit 66, and the gas separation unit 21.

FIG. 4 is a flow diagram in a case where an exhaust gas recovery container 63 is connected to an exhaust gas outlet 2 of a gas separation unit 21 and a gas supply unit 100 is connected to a container 26 to be recovered.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inlet of to-be-recovered gas 1 'Outlet of to-be-recovered gas 2 Outlet of exhaust gas 2' Inlet of exhaust gas 3 Outlet of SF6 gas 4 Adsorption cylinder 5 Adsorption cylinder 6 Exhaust gas tank 7 Pump 8-19 Solenoid valve 20 Concentration of SF6 gas Sensor 21 Gas separation unit 22 Pressurization unit 23 Liquefaction unit 24 Storage tank 25 Nitrogen gas supply unit 26 Recovered container 27 Nitrogen gas cylinder 28 Pressure reducing valve 29 Solenoid valve 29 ′ Electromagnetic valve 30 Buffer tank 31 Pressure pump 32 Pressure reducing valve 33 Cooler 34 solenoid valve 35 liquefaction tank 36 pressure sensor 37 solenoid valve 40 outside air supply unit 41 air filter 42 air pump 43 dryer 44 supply outside air outlet 51 solenoid valve 52 solenoid valve 55 SF6 gas cylinder 57 pressure reducing valve 63 exhaust gas recovery container 64 solenoid valve 64 ′ Solenoid valve 65 Boost pump 66 Gas take-out part 67 Solenoid valve 68 Solenoid valve 69 Pressure reducing valve 70 Outside air intake 100 Gas supply unit

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[Procedure amendment]

[Submission date] June 6, 2000 (2000.6.6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

It should be noted that the equalizing step in the description of the flow charts of FIGS. 2A and 2B can be omitted depending on the capacity of the apparatus. Next, FIG. 4 shows an example of filling. The description will be made using this. FIG. 2 shows a gas supply unit 100 capable of supplying SF6 gas and dilution gas by an SF6 gas supply source 60 constituted by an SF6 gas cylinder 55 and a pressure reducing valve 57, and a dilution gas supply source 25 constituted by a nitrogen gas cylinder 27 and a pressure reduction valve 28. In the gas separation / collection / filling device having the pressure sensor 36 and the concentration sensor 20 in the gas separation unit 21, the collection target container 26 and the gas supply unit 100 are connected by a conduit, and the pressure sensor 36 and the concentration sensor 20 are connected.
The gas mixture in the container to be recovered is connected to the container via a conduit, and the pressure and concentration of the gas mixture are measured. Although not shown in the figure, the pressure sensor 36 and the concentration sensor 20 are connected to signal lines. The control unit is also connected to the gas supply unit via a signal line, which is also omitted in the figure, and is diluted from the gas supply unit 100 to the container 26 to be recovered by an instruction from the control unit. The gas and SF6 gas are controlled and introduced, and the diluted gas is introduced into the container 26 to be recovered by opening the valve 29 'according to the instruction of the control unit, and the outside air remaining in the container is recovered. After discharging a certain amount from the container 26, the SF
6 gas is introduced by opening the valve 29, and while detecting the pressure and concentration in the container to be recovered by the pressure sensor 36 and the concentration sensor 20, the SF6 gas is supplied from the gas supply unit so as to reach a predetermined filling pressure and concentration. And supply (fill) while controlling the dilution gas.

Claims (11)

[Claims] 1. A container to be recovered and a gas separation unit are connected by a conduit, and a gas to be recovered in which a plurality of types of gases are mixed in the container to be recovered is separated by the gas separation unit. A gas separation / recovery / filling apparatus characterized in that the gas is recovered and the other gas is returned to the container to be recovered via a conduit and filled. 2. The gas separation / recovery filling apparatus according to claim 1, wherein the gas to be recovered is a mixed gas obtained by mixing SF6 gas and diluent gas. 3. One of the gases separated by the gas separation unit is SF.
The gas separation / recovery / filling apparatus according to claim 1, wherein the six gases are used, and the other gas is a dilution gas. 4. The gas separation / recovery filling apparatus according to claim 1, wherein one of the gases separated by the gas separation section is a diluent gas, and the other gas is a SF6 gas. 5. A gas separation / recovery / filling apparatus having a gas separation unit, wherein a gas to be recovered including a SF6 gas is introduced from a container to be recovered into the gas separation unit, and separated into a SF6 gas and another diluent gas. The gas is recovered and the diluted gas is returned to the container to be recovered and filled. When the concentration of the SF6 gas in the gas to be recovered falls below a predetermined value, the diluted gas is removed from the atmosphere. A gas separation / recovery / filling apparatus characterized in that the gas is discharged into the apparatus. 6. In a gas separation / recovery / filling apparatus having a gas separation unit and a gas supply unit, a recovery target gas including SF6 gas is introduced from a recovery target container into the gas separation unit, and is converted into SF6 gas and another dilution gas. The SF6 gas is collected by separation, and the diluted gas is returned to the container to be recovered. When the pressure of the gas in the container to be recovered to be introduced into the gas separation unit becomes lower than a predetermined value, the gas is recovered. A gas separation / recovery / filling apparatus characterized in that a gas is introduced from a gas supply part into the container to be recovered and charged. 7. The gas separation / recovery / filling apparatus according to claim 6, wherein the gas supplied from the gas supply section is a nitrogen gas. 8. The gas separation / recovery / filling device according to claim 6, wherein the gas supplied from the gas supply unit is air. 9. In a gas separation / recovery / filling apparatus having a gas separation unit, the gas separation unit separates the SF6 gas into another diluent gas, and returns the dilute gas partially containing the SF6 gas to the container to be collected. The gas separation / recovery / filling device is configured as described above, and when the pressure of the container to be recovered falls below the atmospheric pressure, outside air is introduced into the container to be recovered. 10. A gas separation / recovery / filling device having a gas supply unit capable of supplying SF6 gas and dilution gas, a pressure sensor, and a concentration sensor, wherein the container to be recovered and the gas supply unit are connected by a conduit, and the pressure sensor and the concentration sensor are connected. The mixed gas in the container to be collected is connected by a conduit, the pressure and concentration of the mixed gas are measured, a diluent gas is introduced into the container to be recovered from the gas supply unit, and the outside air remaining in the container is removed. After exhausting a certain amount from the container to be recovered, SF6 gas is introduced, and the pressure and concentration in the container to be recovered are detected by the pressure sensor and the concentration sensor, and the gas is supplied from the gas supply unit to a predetermined filling pressure and concentration. A gas separation / recovery / filling apparatus characterized in that SF6 gas and dilution gas are supplied while being controlled and charged. 11. A gas separation / recovery / filling apparatus having a gas separation unit, a gas supply unit capable of supplying SF6 gas and a dilution gas, a pressure sensor, and a concentration sensor, wherein a container to be recovered and a gas supply unit are connected by a conduit. The mixed gas in the recovery container is connected to the gas separation unit, the pressure sensor, and the concentration sensor via a conduit, and the pressure and concentration of the mixed gas are measured. SF6 gas and diluent gas are controlled and introduced from the gas supply unit. The mixed gas is supplied from the collection container while supplying a gas from a supply unit so as to have a predetermined filling pressure and concentration while detecting the pressure and concentration in the collection container by the pressure sensor and the concentration sensor. Introduced into the gas separation section, separated into SF6 gas and diluent gas containing outside air, SF6 gas is returned to the container to be collected, and the diluting gas containing outside air is discharged out of the container to be collected. And a gas separation, collection and filling device.