JP2001103626A - Gas recovering apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact gas recovering apparatus which can recover effectively specified gas from mixed gas, with very high recovery, in a short time. SOLUTION: An SF6 gas adsorbing apparatus 3 and a nitrogen gas-adsorbing apparatus 4 are installed. Adsorbent which adsorbs SF6 gas easily is charged in the SF6 gas adsorbing apparatus 3, and adsorbent which adsorbs nitrogen gas easily is charged in the nitrogen gas adsorbing apparatus 4. A compressor 2b as a liquefying apparatus, a heat exchanger 6 and an SF6 tank 7 are connected with the SF6 gas adsorbing apparatus 3. A gas discharge apparatus 14 is connected with the nitrogen gas absorbing apparatus 4 via a vacuum pump 9b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas recovery apparatus used for gas insulation equipment used in electric power equipment, and more particularly to an environmentally friendly gas recovery apparatus in which a small amount of SF6 gas is added to nitrogen gas as an insulation gas. The present invention relates to a gas recovery device suitable for gas insulation equipment.

[0002]

2. Description of the Related Art Substations are provided with devices such as circuit breakers and disconnectors for use in system switching, maintenance and inspection. Particularly large-sized ones of these devices are filled with SF6 gas, and are collectively referred to as gas-insulated switchgear (GIS). SF6 gas is excellent in insulating performance and arc extinguishing performance, and is chemically stable and harmless gas, and is widely used as an insulating medium for these devices.

However, it has recently been pointed out that SF6 gas has a very high greenhouse effect. In addition, because of its long life until decomposition, it has been designated as an emission control object for the purpose of protecting the global environment for a long time in the future. For this reason, after testing the gas-insulated switchgear or during internal inspections on site, the SF6
It is necessary to recover the gas from the gas insulated switchgear so as not to discharge the gas to the outside. At present, it is common to collect and store the gas as it is in another tank, or to liquefy the gas under pressure by a liquefier and collect and store it as a liquid in the tank. SF6
If the purity of the gas is high, it can be liquefied at a relatively low pressure even at room temperature, and it is easy to collect and store. Here, a conventional example of a gas recovery device connected to a gas insulating device will be specifically described with reference to FIG.

The gas-insulated equipment 1 such as a gas-insulated switchgear is connected to interlocking valves 12a and 12b. The buffer tank 5 is connected to the interlocking valve 12a via the pressure reducing valve 11a. On the other hand, the interlocking valve 12b is connected to the buffer tank 5 via the vacuum pump 9. The buffer tank 5 keeps the gas pressure relatively low. Further, the compressor 2 is connected to the buffer tank 5 through a filter 10, and the heat exchanger 6 and the SF 6
The tank 7 is connected. The compressor 2, the heat exchanger 6, and the SF6 tank 7 constitute a liquefaction apparatus.

The operation of the above conventional example will be described below. That is, when the gas pressure of the gas insulating device 1 is high, the interlocking valve 12a is opened and the interlocking valve 12b is closed, whereby the gas automatically flows into the buffer tank 5. At this time, the inflow gas amount is adjusted by the pressure reducing valve 11a so that the gas pressure in the buffer tank 5 does not become too high. On the other hand, gas recovery has progressed to some extent, and gas insulation equipment 1
When the gas pressure of the gas approaches the atmospheric pressure, the interlocking valve 12a
Is closed and the interlocking valve 12b is opened to operate the vacuum pump 9. Thereby, the gas in the gas insulating device 1 can be completely moved to the buffer tank 5.

[0006] The gas transferred to the buffer tank 5 in this manner is subjected to removal of foreign matter and dust by a filter 10, is pressurized by a compressor 2, is cooled by a heat exchanger 6, is liquefied, and has a reduced volume. It is stored in the SF6 tank 7 in an extremely small state. At this time, SF6 tank 7
Has a gas phase, but most of it is gaseous SF6,
Only a slight amount of gas as an impurity is added to this. When the SF6 gas is used again, the valve 13 is connected to the apparatus to be used using the valve 13 and the valve 13 is opened to fill the SF6 gas.

However, considering the long-term global environment, it is necessary to further reduce the amount of SF6 gas emitted in the future. For this purpose, it is necessary to reduce the amount of SF6 gas used, which is also a factor of emission. Is desirable. As part of these measures, the use of a mixed gas containing a small amount of SF6 gas is positioned and is considered to be effective for reduction.

As a highly feasible method, it has been considered to add a small amount of SF6 gas using nitrogen gas as a base. However, in such a mixed gas system, the equipment becomes larger due to the problem that SF6 gas does not liquefy unless the pressure is set to a high pressure and the need to reduce the liquefaction pressure by using a large refrigeration system or cooling with liquid nitrogen. It can be an obstacle to collection and recycling.

That is, as shown in Table 1, the current pure SF
6 Gas can be liquefied at relatively low pressure, but SF6
In the case of a mixed gas in which a gas is added at a low ratio, high pressure is indispensable for liquefaction. More specifically, in the case of 10 vol% SF6 gas, a very large pressure of about 20 MPa or more is required at room temperature, which raises a specific problem that liquefaction is difficult in practice.

[0010]

[Table 1] To store a large amount of gas in a gaseous state,
It must be collected in a large tank, but requires a large volume. Further, in order to reduce the volume of the recovered gas, the gas must be stored at a high pressure, but in this case, a problem in safety is likely to occur. Furthermore, it is most economical to release non-liquefied gas other than SF6, that is, nitrogen gas, to the atmosphere when recovering SF6 gas.
There is a strong demand to ensure that SF6 gas is not included in the released gas. As mentioned above, out of the mixed gas
There is a major issue regarding the technology for recovering SF6 gas, and it is urgently necessary to establish a recovery technology at the same time as conducting research on the insulating properties of mixed gas.

With respect to a mixed gas separation / recovery device, a device for separating single gases of various components (for example, oxygen gas) from air has already been developed and actually used. This gas separation and recovery device separates air into nitrogen gas and oxygen gas and recovers only oxygen gas. The outline of the device will be described with reference to FIG.

As shown in the figure, a compressor 2a is provided, to which a nitrogen gas adsorption device 4 is connected. The nitrogen gas adsorption device 4 is loaded with an adsorbent that easily adsorbs nitrogen gas. Further, a gas tank 17 for storing oxygen gas is connected to the nitrogen gas adsorption device 4 via a compressor 2b. Further, the nitrogen gas adsorption device 4 is provided with an air release device 1 that releases nitrogen gas to the atmosphere via a vacuum pump 9.
4 are connected.

In the gas separation and recovery apparatus having such a configuration, air is compressed by the compressor 2a and sent to the nitrogen gas adsorption apparatus 4. In the nitrogen gas adsorption device 4, the adsorbent adsorbs only nitrogen gas in the air. Most of the gas that has passed through the nitrogen gas adsorption device 4 becomes oxygen gas. The compressor 2b compresses the oxygen gas that has passed through the adsorption device 4,
The gas tank 17 stores this.

If this process is continued for a sufficient time, the adsorbent of the nitrogen gas adsorbing device 4 can no longer adsorb nitrogen gas. Before this state, the compressors 2a,
2b is stopped, and the nitrogen gas adsorber 4 is
When the gas pressure in the inside is reduced, the adsorbent of the nitrogen gas adsorption device 4 releases the adsorbed nitrogen gas, and returns to a state where the nitrogen gas can be adsorbed again. This gas is released from the air release device 14 into the atmosphere.

The adsorbent in the nitrogen gas adsorption device 4 can be used semipermanently by alternately repeating adsorption and release (regeneration). For example, a synthetic zeolite is used as a nitrogen gas adsorbent for an oxygen generator for an ozonizer. Synthetic zeolite is a general term for the group of hydrous aluminosilicate minerals and is represented by the general formula MeO.Al2O3.mSiO2.nH2O. A metal cation is included in the crystal structure, and this acts to attract a polar group electrostatically or to polarize and attract a polarizable molecule, which is advantageous for neutral molecule adsorption. Product names: Molecular Sieves (UCC), Zeorum, Molecularite (Kurita Kogyo), Nikka Pellets
(Japanese activated clay) is known. In addition, in addition to adsorption by polarization, synthetic zeolite has uniform pores on its surface, and only molecules smaller than these pores are adsorbed inside the cavities through pore channels, so that excellent zeolites are obtained. Shows selective adsorption (molecular sieve effect). For this reason, it is classified according to the size of the pores, 3 angstrom type, 4 angstrom type,
5 angstrom type, 9 angstrom type, 10 angstrom type and the like have been developed.

[0016]

The above-mentioned technology for separating and recovering a single gas from air involves the infinite supply of air as a material, and furthermore, recovers a single gas which is a component of air to be separated and recovered. Since there is no problem in releasing it into the air in a state where it is contained too much, the recovery rate is not so much a problem. In this respect, it is significantly different from the problem to be solved by the present invention. In other words, when recovering mixed gas from environmentally friendly gas-insulated equipment in which a small amount of SF6 gas is added to nitrogen gas, an extremely high SF6 gas recovery rate is required despite the limited amount of mixed gas. . This is not only the economic aspect,
This is because the amount contained in the gas released into the air must be reduced to almost zero due to a completely new problem of environmental problems.

However, if a large amount of electric energy is used to recover the SF6 gas, which is a greenhouse gas, a large amount of CO2 gas will be emitted, which is a tough end. Therefore, it is important to improve the recovery efficiency while reducing the power consumption, rather than simply increasing the gas recovery rate.

At the same time, it is strongly required to shorten the time required for gas recovery. As mentioned above, one of the purposes of gas recovery at the substation is to inspect the inside of the equipment, but at this time, the equipment is in a stopped state. However, in order to stably supply power, such stoppages must be reduced as much as possible. Therefore, it is desirable to shorten the time required for the internal inspection, and it is expected that the gas recovery work will be speeded up.

Further, at present, substations in large cities are often constructed underground due to difficulty in obtaining land. When recovering SF6 gas at such a substation, the gas recovery device must be transported by an elevator or the like. Therefore, an extremely compact gas recovery device is required.

The present invention has been proposed to solve the above problems, and an object of the present invention is to provide a compact gas that can efficiently and quickly recover a specific gas from a mixed gas at an extremely high recovery rate. Another object of the present invention is to provide a simple gas recovery device.

[0021]

SUMMARY OF THE INVENTION The present invention has been proposed in order to achieve the above object, and is an apparatus used for a gas insulating device filled with a mixed gas comprising a plurality of types of insulating gases. In a gas recovery device provided with a liquefaction device that has at least a compressor and a heat exchanger, takes in the mixed gas from the gas insulating device, and liquefies a specific gas in the mixed gas, has the following features. I have.

According to a first aspect of the present invention, there are provided two adsorbers having different types of gases to be adsorbed, the first adsorber being connected to the liquefaction apparatus, and the second adsorber being connected to the liquefaction apparatus. A gas discharge device for discharging the gas adsorbed by the adsorption device to the atmosphere is connected.

According to the first aspect of the present invention, one of the adsorbers can adsorb the gas to be collected and the other adsorber can adsorb the gas not to be collected. It is possible to increase.

According to a second aspect of the present invention, there is provided the gas recovery apparatus according to the first aspect, wherein the gas which is not adsorbed by the first adsorber and passes therethrough is guided to the second adsorber. The base adsorption device is connected.

In the second aspect of the present invention, the concentration of the gas component which has not been adsorbed by the first adsorber and passed without being adsorbed increases. By making this high-concentration gas the gas to be adsorbed by the second adsorption device,
Can obtain a high gas recovery rate.

According to a third aspect of the present invention, in the gas recovery apparatus of the second aspect, the gas which has not been adsorbed by the second adsorber and has passed therethrough is guided to the first adsorber again. It is characterized in that two adsorption devices are connected.

According to the third aspect of the present invention, a closed loop of the mixed gas can be formed by connecting two adsorption devices in series. Therefore, in addition to the function and effect described in the second aspect, the first adsorption device can also obtain a high gas recovery rate. That is, the concentration of gas components that have not been adsorbed in the gas that has passed through the second adsorber increases, and this high-concentration gas is used as the gas to be adsorbed by the first adsorber. Is improved. Moreover, since the liquefaction device and the air release device are connected as branches branching from the closed loop, the circulation of the mixed gas can be performed regardless of the operation of the liquefaction device or the gas release device. Further, the composition of the mixed gas circulating in the closed loop does not change depending on the number of circulations, the energy loss is small, and a high gas recovery rate and high efficiency are stably realized.

The invention of claim 4 is the invention of claim 1, 2, or 3.
In the gas recovery device described above, the first adsorption device and the liquefaction device are connected so that the gas that has not been liquefied by the liquefaction device is again guided to the first adsorption device.

According to the fourth aspect of the present invention, the gas which has not been liquefied by the liquefaction apparatus is guided again to the first adsorption apparatus, so that the gas recovery rate can be further increased.

According to a fifth aspect of the present invention, two adsorbers having different types of gas to be adsorbed are provided, and the liquefier and the adsorber are divided and installed on a plurality of movable carts. Features.

According to the fifth aspect of the present invention, the components of the gas recovery device are divided and installed on a plurality of trolleys, whereby compactness can be achieved, and even when the gas recovery device is transported to an underground substation. The device can be easily mounted on an elevator or the like.

According to a sixth aspect of the present invention, in the gas recovery apparatus according to the fifth aspect, the adsorption device is installed on one truck, and the liquefaction device is installed on the other truck.

According to the sixth aspect of the present invention, pure SF6 gas can be recovered using only the truck provided with the liquefaction apparatus, and the operation rate of the gas recovery apparatus can be increased. It is also very convenient when used in a substation where pure SF6 gas insulation equipment and mixed gas insulation equipment coexist. In addition, there are many parts where the conventional gas recovery device can be used as it is, which is economical.

According to a seventh aspect of the present invention, there are provided two adsorbers having different types of gas to be adsorbed, and each adsorber accommodates two adsorbers having the same capacity. Are connected by a gas pipe, and when one adsorbing section takes an adsorbing step of adsorbing gas, the other adsorbing section takes a releasing step of releasing the adsorbed gas.

According to the seventh aspect of the present invention, when each of the adsorbing sections takes an adsorbing step of adsorbing a gas and the other adsorbing section takes a releasing step of releasing the adsorbed gas, the respective adsorbing sections take a releasing step of releasing the adsorbed gas. Can be periodically replaced, and steady operation can be performed in the entire system. Thereby, power consumption at the time of starting the device can be saved, and the efficiency of gas recovery is improved.

According to an eighth aspect of the present invention, in the gas recovery apparatus of the seventh aspect, the two adsorbing portions are thermally coupled.

In the eighth aspect of the present invention, attention is paid to the point that the adsorbing section needs to be cooled in the discharging process and needs to be heated in the endothermic process. That is, since the two adsorbing portions are thermally coupled to each other to facilitate the transfer of heat therebetween, the heat generated in the releasing process of one adsorbing portion is used for heating in the adsorbing process of the other adsorbing portion. be able to. Therefore, the efficiency of adsorption and release (regeneration) can be increased without consuming special electric power.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) First Embodiment. Corresponding to Claims 1 to 4 [Configuration] FIG. 1 is a configuration diagram of a gas recovery apparatus according to a first embodiment of the present invention. Here, the same components as those of the conventional gas recovery apparatus shown in FIGS. 6 and 7 described above are denoted by the same reference numerals, and description thereof is omitted.

The first embodiment is characterized in that an SF6 gas adsorbing device 3 is installed together with a nitrogen gas adsorbing device 4 in two different adsorbing devices of different types of gas to be adsorbed. The SF6 gas adsorption device 3 is loaded with an adsorbent that easily adsorbs SF6 gas. The SF6 gas adsorption device 3 includes a compressor 2b as a liquefaction device and a heat exchanger 6
The SF6 tank 7 is connected, and the nitrogen gas adsorption device 4 is connected to an air release device 14 via a vacuum pump 9b. At this time, the compressor 6
The gas transferred to b is the SF6 gas adsorbed by the adsorption device 3, and the gas transferred from the nitrogen gas adsorption device 4 to the vacuum pump 9b is the nitrogen gas adsorbed by the adsorption device 4.

Gases that have not passed through the SF6 gas adsorbing device 3 and have passed therethrough are led to the nitrogen gas adsorbing device 4, and gases that have passed through without being adsorbed by the nitrogen gas adsorbing device 4 are buffered again. It is configured to enter the tank 5 and be guided to the SF6 gas adsorption device 3. In addition, SF6
A gas pipe 18 is connected to an upper portion of the tank 7, and is connected to the buffer tank 5 via a pressure reducing valve 11b. Further, a storage tank 8 composed of a liquefied gas cylinder or the like is connected to a lower portion of the SF6 tank 7.

[Operation] The operation of the first embodiment having such a configuration is as follows. By the operation of the compressor 2a, the mixed gas can be circulated many times in the closed loop returning to the compressor 2a again through the SF6 gas adsorber 3, the nitrogen gas adsorber 4, the buffer tank 5, and the filter 10. The operation of the SF6 liquefier, which includes the compressor 2b, the heat exchanger 6, and the SF6 tank 7, is influenced by the branch of the closed loop through the adsorber 3 as a branch. Absent. On the other hand, since the nitrogen gas discharge device including the vacuum pump 9b and the gas discharge device 14 is also connected as a branch branched via the adsorption device 4, its operation affects gas circulation in the closed loop. Absent.

Next, as the action of the closed loop, the state (change) of the gas moving here will be described. The mixed gas of SF6 gas and nitrogen gas taken into the buffer tank 5 from the gas insulating device 1 has a specific mixing ratio.
Since the SF6 gas is selectively adsorbed by the 6 gas adsorber 3, the mixed gas leaving the SF6 gas adsorber 3 becomes a nitrogen gas rich gas having a small amount of SF6 gas components and enters the nitrogen gas adsorber 4. Since the nitrogen gas adsorbing device 4 selectively adsorbs nitrogen gas, the mixing ratio of the gas exiting the nitrogen gas adsorbing device 4 approaches the mixing ratio of the mixed gas initially taken into the buffer tank 5. Therefore, there is no large difference between the mixture ratio of the gas returned to the buffer tank 5 after circulating through the closed loop and the mixture ratio of the gas already existing in the buffer tank 5, and the mixture ratio of the two gases is a new mixture ratio. Will not change much.

On the other hand, liquefied SF6 flows into the SF6 tank 7, and the liquefied SF6 is transferred to the storage tank 8 and stored therein. The upper portion of the SF6 tank 7 contains, at the same time as the SF6 gas which is not liquefied, a slight amount of nitrogen gas which has been taken in as the adsorption gas of the adsorption device 3. Although the mixing ratio of this nitrogen gas is small, as the recovery proceeds, pure liquefied SF6 is selectively transferred to the storage tank 8, so that the nitrogen gas concentration in the gaseous phase portion above the SF6 tank 7 gradually increases. . At this time, the pressure reducing valve 11b is operated, and the gas pipe 1
The nitrogen gas accumulated in the SF6 tank 7 is discharged by returning the gas in the upper part of the SF6 tank 7 to the buffer tank 5 again through 8.

[Effect] The compressor 2a for circulating the mixed gas has a pressure of about several atmospheres, while the liquefaction of the SF6 gas requires a pressure of 20 atmospheres or more at room temperature even for pure SF6. . Therefore, the compressor 2b requires larger electric power than the compressor 2a. Further, the purity of the SF6 gas entering the compressor 2a constituting the liquefaction apparatus decreases (that is, the amount of nitrogen gas increases).
We have already mentioned that the necessary pressure will increase. Here, when the required pressure increases, the electric power required for compression increases more than the increase in pressure. Therefore, even if the operation efficiency of the compressor 2a is sacrificed to some extent, increasing the operation efficiency of the compressor 2b can reduce power consumption as a whole. That is, SF6 of the gas flowing into the liquefier
It is better to increase the gas concentration as much as possible.

On the other hand, it is necessary to minimize the amount of SF6 gas contained in nitrogen gas released to the atmosphere from the viewpoint of the global environment. Global warming index of SF6 gas is 2 of carbon dioxide gas
Since it is said to be 4000 times, the equivalent power consumption when SF6 gas is contained in the gas released to the atmosphere is:
It can be said that the power required for other devices is incomparable. Therefore, the priority is given to the purity of nitrogen gas released to the atmosphere, and SF6 taken into SF6 liquefaction equipment
6 It can be said that it is best to make the gas purity second and the efficiency of the compressor 2a third.

Generally, when comparing the purity of the gas adsorbed with the gas adsorbed by the adsorption device, it is easier to increase the purity of the gas adsorbed. That is, the more the gas circulation in the closed loop is repeated, the higher the purity of the adsorbed gas.

According to the first embodiment, the SF6 gas taken into the heat exchanger 6 by the compressor 2b is adsorbed by the adsorber 3, and the SF6 gas is taken into the air taken into the air vent 14 by the vacuum pump 9b. The released nitrogen gas is also adsorbed by the adsorber 4 in the same manner. Therefore, both gases can be expected to have considerably high purity. Further, an SF6 gas adsorbing device 3 is provided in front of the nitrogen gas adsorbing device 4, and a nitrogen-rich mixed gas in which SF6 gas is adsorbed is injected into the nitrogen gas adsorbing device 4. Can be expected to be nitrogen gas of higher purity.

Moreover, the buffer tank 5 and the filter 1
0, the compressor 2a, the adsorption device 3 and the adsorption device 4 form a closed loop because the two adsorption devices 3 and 4 both use the gas passage passing therethrough.
The gas circulation requires only one compressor 2a and is not only efficient, but also can be operated independently of the SF6 gas liquefaction process and the nitrogen gas discharge process. This makes it extremely easy to increase the purity of the nitrogen gas released to the atmosphere within the time constraints required for gas recovery.

According to thermodynamics, mixing hot and cold gases without any effect increases entropy and energy loss by itself.
Similarly, for example, when a gas with a high SF6 content is mixed with a gas with a low SF6 gas content,
A large increase in entropy appears, leading to energy loss. Therefore, it is desirable that the mixing ratio of the gas circulating through the loop and returning to the original starting point is as close as possible to the mixing ratio at the starting point. As described above, in the first embodiment, the mixing ratio of the gas that returns to the starting point after completing the closed loop circulation is close to the mixing ratio at the starting point. Therefore, it can be said that extremely efficient recovery is possible. Also, even if the number of times the gas circulates in the closed loop increases, the fact that the mixing ratio of this gas does not change much is
This means that the system can always perform the same operation, and there is little energy loss, which is also advantageous in this respect. As described above, according to the first embodiment, SF6 gas can be efficiently recovered at an extremely high recovery rate from an environmentally compatible gas insulating device in which a small amount of SF6 gas is added to nitrogen gas.

(2) Second Embodiment: Claims 5 and 6
[Configuration] FIG. 2 is a configuration diagram of a gas recovery apparatus according to a second embodiment of the present invention. In the second embodiment, two movable carts 15a and 15b are provided. The truck 15a includes a compressor 2a, an SF6 gas adsorber 3, a nitrogen gas adsorber 4, a vacuum pump 9b,
The vacuum pump 9a, the buffer tank 5, the filter 10, the compressor 2b, the heat exchanger 6, and the SF6 tank 7 are installed on the other carriage 15b. Here, the storage tank 8 is a liquefied SF6 cylinder and is provided independently of the carriage 15b instead of being provided on the carriage 15b.

A valve 13b is provided on the gas outlet side of the filter 10, a valve 13c is provided on a gas inlet side of the compressor 2a, a valve 13d is provided on a gas inlet side of the nitrogen gas adsorber 4, and a pressure reducing valve 11b. A valve 13e is provided on the gas outlet side of the compressor 6b, a valve 13f is provided on the gas outlet side of the SF6 gas adsorber 3, a valve 13g is provided on a gas inlet side of the compressor 2b, and the filter 10 and the compressor 2 are provided.
b and a valve 13i on the gas pipe connecting the SF6 tank 7 and the storage tank 8.
And 13q have a valve 13r downstream of the storage tank 8.
Are provided respectively.

[Operation] Now, the valve 13b and the valve 13
c, connecting the valve 13d and the valve 13e, and connecting the valve 13f and the valve 13g, and opening these valves and closing the valve 13h, the truck 15a and the truck 15
By synthesizing the device installed in b, it is possible to obtain the completely same configuration as the gas recovery device shown in FIG. On the other hand, when the valves 13b, 13e and 13g are closed and the valve 13h is opened, the device installed on the truck 15b has exactly the same configuration as the conventional pure SF6 gas recovery device shown in FIG.

[Effect] A plurality of trolleys 1 are obtained by dividing the components.
By installing the trolleys at 5a and 15b, one trolley can be reduced in size so that it can be mounted on an elevator or the like, and can be easily transported to an underground substation. In addition to this effect, according to the second embodiment, pure SF6 gas is recovered from the mixed gas containing SF6 gas, and
SF6 gas can be recovered from SF6 gas as before. Therefore, the operating rate of the gas recovery unit can be increased, and at the same time, it can be applied to the case where it is used in a substation where pure SF6 gas insulation equipment and mixed gas insulation equipment coexist, etc. Can be used in a range. Further, the second embodiment is economically advantageous because it is possible to obtain a component for recovering the mixed gas by slightly repairing the conventional gas recovery device.

(3) Third Embodiment: Claims 7 and 8
[Configuration] FIG. 3 is a configuration diagram of an SF6 gas adsorption device 3 of a gas recovery device according to a third embodiment of the present invention. The SF6 gas adsorber 3 has metal tanks 3a,
3b are stored. The metal tanks 3a, 3b
Valves 13j, 13k, 131, 13m, 13n, 13
They are connected in parallel via p, and an SF6 gas adsorption device 3 is formed as a whole of the system. Also, one metal tank 3
When a takes an adsorption process of adsorbing a gas, the other 3b takes a release process of releasing the adsorbed gas. Although not shown in the drawings, the suction device 4
Has the same configuration. In the figure, A is a mixed gas inlet, B is a passing gas outlet, and C is an adsorption gas outlet.

[Operation] As described above, it is necessary that the adsorption devices 3 and 4 alternately repeat the adsorption process and the release process (regeneration process). Therefore, if two adsorption devices of the same scale are prepared, one of them is operated as an adsorption process, and the other is operated as a release process (regeneration process), steady operation of the whole system becomes possible.

Now, in the SF6 gas adsorption device 3, the valves 13j and 13l are opened and the valves 13k, 13m and 1
3n is closed, and the metal tank 3a takes an adsorption process. Then, the valve 13p is opened, and the SF6 gas adsorbed in the metal tank 3b is sent to the liquefier. When the adsorption process of the metal tank 3a is completed, the valves 13j, 131, and 13p are closed, and then the valves 13k, 13m, and 13n are opened, so that the metal tank 3b enters the adsorption process, and the metal tank 3a is closed. The release process (regeneration process) occurs, and the roles are switched.

[Effect] As described above, in the third embodiment, the two systems of the adsorption process and the release process (regeneration process) are alternately repeated, so that the entire system can be operated constantly. it can. Generally, vacuum pumps and compressors require a large amount of power at startup,
According to the third embodiment, in which a steady operation is possible, these devices can be largely saved without stopping, and the efficiency of recovery can be improved.

Further, by combining with the first embodiment, a synergistic effect of both can be expected. That is, the adsorption process and the release process of the adsorption device 3 and the adsorption device 4 (
By performing the replacement of the regeneration process completely independently, the amount of SF6 contained in a trace amount in the nitrogen gas released into the atmosphere can be easily controlled, and a gas recovery device that is economical and has a high recovery rate can be realized. Can be provided.

(4) Fourth Embodiment Corresponding to Claim 8 [Structure] FIG. 4 is a structural view of a nitrogen gas adsorption device 4 of a gas recovery device according to a fourth embodiment of the present invention. Although not shown in the drawings, the suction device 3 can have a similar configuration. The feature of the fourth embodiment is that the nitrogen gas adsorption device 4 has a metal tank 4 as an adsorption unit having the same capacity.
a and 4b are connected in parallel, and one metal tank 4
The point is that a gas pipe 16a serving as a passage for gas exiting from a is disposed in close contact with the tank surface of the other metal tank 4b. Similarly, a gas pipe 16b serving as a passage for gas exiting from the metal tank 4b is disposed in close contact with the tank surface of the other metal tank 4a. The other structure is the same as that of the suction device 3 of the third embodiment shown in FIG.

[Operation] The temperature of the gas rises when compressed,
It is well known that the temperature decreases when the pressure is reduced as a natural phenomenon. Therefore, the adsorption device in the adsorption process is in the heat generation process, and the adsorption device in the release (regeneration) process is in the endothermic process. Meanwhile, the relationship between the amount of adsorbent adsorbed and the temperature is inversely proportional, and is schematically shown in the graph of FIG.

As is clear from this graph, it is desirable that the temperature of the adsorption device in the adsorption process is desirably low, and that the temperature of the adsorption device in the release (regeneration) process is desirably high temperature. In this way, the temperature distribution is completely opposite to the desired state and the state that changes naturally. Since the adsorption process and the release (regeneration) process occur simultaneously in time, the temperature distribution can be shifted to a more preferable one if the thermal coupling between the metal tanks 4a and 4b is strengthened.

The fourth embodiment can realize such a transition of the temperature distribution. For example, if the metal tank 4a is in the adsorption process, this will be a heat generation process and will be high temperature. The gas that has passed without being adsorbed in the metal tank 4a has a high temperature, and the gas pipe 16a also has a high temperature and can be heated because it is in close contact with the metal tank 4b. At this time, since the metal tank 4b is in the release (regeneration) process, the efficiency of the release (regeneration) is further improved by heating.

On the other hand, the gas released from the metal tank 4b is at a low temperature, and the gas pipe 16b is also at a low temperature and is in close contact with the metal tank 4a, so that it can be cooled. At this time, since the metal tank 4a is in the adsorption process, the adsorption efficiency is further improved by cooling.

[Effect] As described above, according to the fourth embodiment, by properly combining the heat generation process and the heat absorption process that always occur, the adsorption and release (regeneration) can be performed without using any special electric power. The efficiency can be greatly improved, and the gas recovery efficiency can be improved. Therefore, not only can the time required for gas recovery be reduced, but also the generation of carbon dioxide gas that contributes to global warming can be reduced as much as possible.

[0065]

As described above, according to the present invention, two adsorbers having different types of gas to be adsorbed are provided, and the liquefier is released to the first adsorber and the second adsorber is discharged to the second adsorber. The extremely simple configuration of connecting each gas device makes it possible to recover specific gases from the mixed gas with extremely high recovery rates.
A compact gas recovery device that can be recovered efficiently and in a short time can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a second embodiment of the present invention.

FIG. 3 is a configuration diagram of an SF6 gas adsorption device 3 according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of a portion of a nitrogen gas adsorption device 4 according to a fourth embodiment of the present invention.

FIG. 5 is a graph showing the relationship between the amount of adsorbent adsorbed and the temperature.

FIG. 6 is a configuration diagram of a conventional example of a gas recovery device.

FIG. 7 is a configuration diagram of a conventional example of an apparatus for separating and recovering a mixed gas.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Gas insulation equipment 2, 2a, 2b ... Compressor 3 ... SF6 gas adsorption device 3a, 3b, 4a, 4b ... Metal tank 4 ... Nitrogen gas adsorption device 5 ... Buffer tank 6 ... Heat exchanger 7 ... SF6 tank 8 ... Storage Tank 9, 9a, 9b Vacuum pump 10 Filter 11a, 11b Pressure reducing valve 12a, 12b Interlocking valve 13, 13a, 13b, 13c, 13d, 13e, 13
f, 13g, 13h, 13i, 13j, 13k, 13
1, 13m, 13n, 13p, 13q, 13r: Valve 14: Air release device 15a, 15b: Truck 16a, 16b, 18: Gas pipe 17: Gas tank A: Mixed gas inlet B: Passing gas outlet C: Adsorption gas outlet

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D012 CA20 CB15 CB16 CD07 CE01 CF01 CG01 CJ02 CK10 4D047 AA07 AB00 BA02 BB03 DA01 5G017 DD07

Claims (8)

[Claims] An apparatus for use in a gas insulating device filled with a mixed gas comprising a plurality of types of insulating gases, comprising at least a compressor and a heat exchanger, wherein the mixed gas is taken in from the gas insulating device. In a gas recovery device provided with a liquefaction device for liquefying a specific gas inside, two adsorption devices having different types of gas to be adsorbed are provided, and the liquefaction device is connected to the first adsorption device. A gas recovery device connected to the second adsorption device, which is connected to an air release device for releasing the gas adsorbed by the adsorption device to the atmosphere; 2. The two adsorbing devices are connected so that a gas that has passed through the first adsorbing device without being adsorbed is guided to the second adsorbing device. 2. The gas recovery device according to 1. 3. The two adsorbing devices are connected so that a gas that has passed through the second adsorbing device without being adsorbed by the second adsorbing device is guided again to the first adsorbing device. Item 3. The gas recovery device according to Item 2. 4. The first adsorbing device and the liquefying device are connected so that gas not liquefied by the liquefying device is guided again to the first adsorbing device. Or the gas recovery device according to 3. 5. An apparatus for use in a gas insulating device filled with a mixed gas comprising a plurality of types of insulating gases, comprising at least a compressor and a heat exchanger, incorporating the mixed gas from the gas insulating device, and mixing the mixed gas. In a gas recovery device provided with a liquefaction device for liquefying a specific gas therein, two adsorption devices having different types of gas to be adsorbed are provided, and the liquefaction device and the adsorption device have a plurality of movable carts. A gas recovery device which is divided and installed. 6. The gas recovery device according to claim 5, wherein the adsorption device is installed on one truck, and the liquefaction device is installed on the other truck. 7. An apparatus for use in a gas insulating device filled with a mixed gas comprising a plurality of types of insulating gases, comprising at least a compressor and a heat exchanger, incorporating the mixed gas from the gas insulating device, and mixing the mixed gas. In a gas recovery device provided with a liquefaction device that liquefies a specific gas inside, two adsorption devices with different types of gas to be adsorbed are provided, and each adsorption device has two adsorption units of the same capacity. These two adsorbing sections are connected by a gas pipe, and when one adsorbing section takes an adsorbing step of adsorbing gas, the other adsorbing section takes a releasing step of releasing the adsorbed gas. A gas recovery device. 8. The gas recovery device according to claim 7, wherein said two adsorbing portions are thermally coupled.