KR20170017633A - APPARATUS AND METHOD for Separation and Recovery of Hexafluorosulfide gas - Google Patents

Abstract

The present invention relates to a method for separating and retrieving sulfur hexafluoride gas. According to an embodiment of the present invention, the method for separating and retrieving sulfur hexafluoride gas comprises the following steps: retrieving waste sulfur hexafluoride gas; eliminating acid gas existing in the retrieved waste sulfur hexafluoride gas; pressurizing the acid gas-eliminated waste sulfur hexafluoride gas and then cooling the same thereafter; adding water into the pressurized and cooled waste sulfur hexafluoride gas to form hydrate of the sulfur hexafluoride gas, and then eliminating residual gas; and separate the hydrate of sulfur hexafluoride gas and then eliminating moisture, so as to finally retrieve sulfur hexafluoride gas.

Description

Technical Field [0001] The present invention relates to an apparatus and a method for separating and recovering sulfur hexafluoride gas,

And an apparatus and a method for separating and recovering sulfur hexafluoride gas.

Sulfur hexafluoride (SF ₆ ) is a chemically stable inert gas which has colorless, odorless, harmless and nonflammable properties at room temperature. It has high insulation strength and is not easy to decompose, so etching and magnesium refining Is used as a cover gas for the process and as an insulated gas for a gas insulated switchgear (GIS: Gas Circuit Breaker).

The global warming index of SF ₆ is about 23,900 times higher than that of CO _{2. Therefore} , there is a high demand for SF ₆ separation and recovery technology in terms of greenhouse gas reduction.

On the other hand, in the case of a heavy SF ₆ for heavy electric power, it is known that the SF ₆ is re-injected and refined in the SF ₆ production process, but only a small fraction of the generated SF ₆ is separated and recovered through this method. But also it proposed a method for processing the waste by pyrolysis SF _6, SF _6, because the lung is to occur at a high concentration, there is a limit to the variety of problems such as equipment corrosion due to decomposition products.

An apparatus and a method for separating and recovering sulfur hexafluoride gas are provided. More particularly, the present invention provides an apparatus and method for separating and recovering sulfur hexafluoride gas using the hydrate formation principle.

The method for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention includes the steps of recovering waste sulfur hexafluoride gas; Removing the acidic gas present in the recovered sulfur hexafluorosulfur gas; Pressurizing and cooling the waste gas hexafluoride gas from which the acid gas has been removed; Adding water to the pressurized and cooled sulfur hexafluoride gas stream to form a hydrate of sulfur hexafluoride gas and removing the residual gas; And dissociating the hydrate of the sulfur hexafluoride gas, and removing water to recover the hexafluorosulfur gas.

In recovering the waste SF6 gas, waste SF6 gas is HF 10 to 10,000 ppmv, SO ₂ 10 to 1,000ppmv, N ₂ 0.1 to 5% by volume, SOF ₂ to 10 5,000ppmv, SOF ₄ 10 to 1,000 ppmv, 0.1 to 5 vol% O ₂ , and SF ₆ as the remainder.

In the step of removing the acid gas present in the recovered sulfur hexafluorosulfur gas, the acid gas may be HF and SO ₂ , SOF ₂ , or SOF ₄ .

The step of removing the acid gas present in the recovered sulfur hexafluorosulfur gas may be to rinse with an aqueous solution containing NaOH or Ca (OH) ₂ to remove the acid gas.

The step of removing the acid gas present in the recovered sulfur hexafluorosulfur gas may be to remove the acid gas by adding activated carbon or molecular sieve.

The step of pressurizing and cooling the acid gas-depleted sulfur hexafluoride gas may be a step of pressurizing and cooling the acid gas-depleted sulfur hexafluoride gas at a pressure of 1 to 15 bar and a temperature of 0 to 10 ° C.

In the step of forming the hydrate of sulfur hexafluoride gas and removing the residual gas, the residual gas may include N ₂ and O ₂ .

The step of forming the hydrate of sulfur hexafluoride gas and removing the residual gas may comprise adding 210 to 250 parts by weight of water to 100 parts by weight of pressurized and cooled sulfur hexafluoride gas.

Anionic surfactants, tetrahydrofuran or ammonium salts may be added to the water.

The anionic surfactant may be sodium dodecylsulfate or linear alkyl benzene sulfonate.

The ammonium salt may be tetrabutylammonium bromide.

The anionic surfactant, tetrahydrofuran or ammonium salt may be added in an amount of 0.001 to 5% by weight based on 100% by weight of the aqueous solution.

The hydrate of sulfur hexafluoride gas can be dissolved at a temperature of 15 to 50 캜.

And pressurizing the recovered sulfur hexafluoride gas to charge the heavy fuel cell.

The apparatus for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention is connected to a recovery unit and a recovery unit for recovering sulfur hexafluoride gas, and the acid gas present in the recovered sulfur hexafluoride gas is removed A first reactor connected to the acid gas removing unit and the acid gas removing unit to pressurize or cool the waste sulfur hexafluoride gas from which acid gas has been removed to form a hydrate of sulfur hexafluoride gas together with the water contained therein, And a second reactor connected to the first reactor for receiving the hydrate of the sulfur hexafluoride gas and decompressing or raising the temperature to dissociate and separate the hexafluorosulfur gas.

The acidic gas removing unit may be charged with an aqueous solution containing NaOH or Ca (OH) ₂ to clean the waste sulfur hexafluoride gas.

The acid gas removing unit may be charged with activated carbon or molecular sieve.

The first reactor can be maintained at a pressure of from 1 to 15 bar and a temperature of from 0 to 10 < 0 > C.

The first reactor is composed of the upper part and the lower part, the upper part collects and discharges residual gas including N ₂ and O ₂ , and the lower part collects the hydrated liquid and can move to the second reactor.

The second reactor can be maintained at a temperature of 15 to 50 < 0 > C.

The upper portion of the second reactor may be equipped with a silica gel, a molecular sieve or a zeolite.

Water dissociated from sulfur hexafluoride gas is collected in the lower portion of the second reactor, and the collected water is introduced into the first reactor to be used for forming hydrate of sulfur hexafluoride gas.

The sulfur hexafluoride gas generated in the heavy electric power can be selectively recovered and concentrated and reused in the heavy electric power, so that the amount of sulfur hexafluoride gas generated in the heavy electric power can be reduced.

It can contribute to greenhouse gas reduction by recovering sulfur hexafluoride gas, which has a high global warming index.

1 is a schematic flowchart of a method for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention.
2 is a schematic block diagram of an apparatus for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention.
FIG. 3 is a graph showing the temperature and pressure of each of Examples and Comparative Examples with respect to time. FIG.

The terms first, second and third, etc. are used to describe various portions, components, regions, layers and / or sections, but are not limited thereto. These terms are only used to distinguish any moiety, element, region, layer or section from another moiety, moiety, region, layer or section. Thus, a first portion, component, region, layer or section described below may be referred to as a second portion, component, region, layer or section without departing from the scope of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified and that the presence or absence of other features, regions, integers, steps, operations, elements, and / It does not exclude addition.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Commonly used predefined terms are further interpreted as having a meaning consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or very formal meanings unless defined otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

1 schematically shows a flowchart of a method for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention. The flowchart of the method for separating and recovering sulfur hexafluoride gas of FIG. 1 is for illustrating the present invention only, and the present invention is not limited thereto. Therefore, the method of separating and recovering sulfur hexafluoride gas can be variously modified.

As shown in FIG. 1, a method for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention includes a step (S10) of recovering sulfur hexafluorosulfur gas, an acidic A step (S20) of removing the acid gas, a step (S30) of pressurizing and cooling the sulfur hexafluorosulfide gas from which the acid gas has been removed, a step of adding water to the pressurized and cooled sulfur hexafluorosulfur gas, (S40) of removing residual gas, dissociating the hydrate of sulfur hexafluoride gas, and removing moisture to recover the sulfur hexafluoride gas (S50). In addition, the separation and recovery method of sulfur hexafluoride gas may further include other steps as required.

First, in step S10, the waste sulfur hexafluoride gas is recovered. At this time, the sulfur hexafluorosulfur gas can be the sulfur hexafluoride gas generated in the heavy electric power. More specifically, it can be a sulfur hexafluoride gas generated from a gas circuit breaker or a gas isolator.

The SF ₆ used in the heavy electric field is decomposed by arc discharge or the like under a high voltage to generate acid gases such as HF, SO ₂ , SOF _{2 and} SOF ₄ . In addition, N ₂ , O ₂ may exist due to external air inflow while recovering the sulfur hexafluoride gas from the heavy electric machine. Specifically lung SF6 gas is HF 10 to 10,000 ppmv, SO ₂ 10 to 1,000ppmv, SOF ₂ 10 to 5,000ppmv, SOF ₄ 10 to 1,000ppmv, N ₂ 0.1 to 5 vol%, O ₂ 0.1 to 5% by volume and an SF ₆ glass parts. In one embodiment of the present invention, impurity gases such as HF, SO ₂ , SOF _2, SOF _4, N ₂ and O ₂ are removed from the waste sulfur hexafluoride gas and pure SF ₆ is recovered.

Next, in step S20, the acidic gas present in the recovered sulfur hexafluorosulfur gas is removed. As mentioned above, the pulverized sulfur hexafluoride gas generated in the heavy electric field contains acidic gases such as HF, SO ₂ , SOF _2, SOF ₄ and the like _, and therefore their removal is essential.

Conventionally, the pretreatment process for the acid gas is complicated and it is difficult to remove the inflow air (N ₂ , O ₂ ) during the recovery process. Therefore, the waste sulfur hexafluoride gas generated in the heavy electricity can not be re-injected into the production process of sulfur hexafluoride gas Sulfur hexafluoride was discarded or released into the atmosphere.

In step S20, the acidic gas is removed by washing with water containing an alkali agent such as NaOH or Ca (OH) ₂ , or by absorbing the acidic gas using an adsorbent such as activated carbon or molecular sieve .

Next, in step S30, the purged sulfur hexafluoride gas from which the acid gas has been removed is pressurized and cooled. By pressurizing and cooling the pulverized sulfur hexafluoride gas from which the acid gas has been removed, only sulfur hexafluoride gas forms hydrate in step S40. At this time, the pressure may be 1 to 15 bar, and the temperature may be 0 to 10 ° C. In the above-mentioned range, the hydrate of sulfur hexafluoride gas is appropriately formed.

Next, in step S40, water is added to the pressurized and cooled sulfur hexafluoride sulfur gas to form a hydrate of sulfur hexafluoride gas, and the residual gas is removed. The residual gas means a gas such as N ₂ and O _{2 in} addition to the acidic gas not removed in the above-described step S20.

The amount of water to be added may be 210 to 250 parts by weight based on 100 parts by weight of pressurized, cooled, purged sulfur hexafluoride gas. If the amount of water is too small, there may arise a problem that not all of the hexafluorosulfur gas becomes hydrate. If the amount of water is too large, the amount of water that needs to be raised in temperature to recover SF ₆ increases and energy consumption may increase.

The water to be added may include an additive to aid hydrate formation of the sulfur hexafluoride gas. The additive may be an anionic surfactant, tetrahydrofuran or ammonium salt. More specifically, the anionic surfactant may be sodium dodecyl sulfate (SDS) or linear alkyl benzene sulfonate (LABS). As the ammonium salt, tetrabutylammonium bromide (tetra- n-butyl ammonium bromide).

The anionic surfactant, tetrahydrofuran or ammonium salt may be added in an amount of 0.001 to 5% by weight based on 100% by weight of the aqueous solution. If the addition amount is too small, the effect of improving the hydrate formation rate may be insignificant. If the addition amount is too large, it may interfere with hydrate formation or may not be as effective as the amount of the added additive. Therefore, the addition amount can be adjusted within the above-mentioned range.

Some of the separated sulfur hexafluorosulfur gas hydrate may be injected again into step S20 and then injected into the hydrate formation reactor after further purification in step S20 to be used for further recovery of sulfur hexafluoride. Another part of the separated sulfur hexafluoride gas hydrate can be decomposed into SO ₂ and HF through the decomposition process.

Next, in step S50, the hydrate of sulfur hexafluoride gas is dissociated, moisture is removed, and the hexafluorosulfur gas is recovered. The hydrate of sulfur hexafluoride gas can be easily dissociated by controlling the temperature. Specifically, the temperature can be raised to 15 to 50 DEG C to dissociate the hydrate of sulfur hexafluoride gas. If the temperature falls outside the above range, dissociation is not smooth, so that the temperature can be controlled within the above-mentioned range.

When the hydrate of the sulfur hexafluoride gas dissociates into sulfur hexafluoride gas and water, there is a sulfur hexafluoride gas and moisture equivalent to the amount of saturated steam in the upper part of the reactor. At this time, water can be adsorbed and removed by using silica gel, molecular sieve or zeolite to remove moisture, and pure sulfur hexafluoride gas can be recovered.

On the other hand, the hexafluoride gas dissociated water is collected and returned to the step S40 and can be used for forming the hydrate of sulfur hexafluoride gas in the step S40.

The recovered sulfur hexafluoride gas can be pressurized and charged in the heavy electricity. At this time, the pressure may be 2 to 5 bar. The pressurized sulfur hexafluoride gas may also be used to purge the hydrate reactor in step S40 described above to remove the residual gas.

2 schematically shows a configuration of an apparatus for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention. The arrangement of the apparatus for separating and recovering sulfur hexafluoride gas of FIG. 2 is merely for illustrating the present invention, and the present invention is not limited thereto. Therefore, the apparatus for separating and recovering sulfur hexafluoride gas can be modified in various ways.

2, the apparatus for separating and recovering sulfur hexafluoride gas according to an embodiment of the present invention includes a recovery unit 10 for recovering waste sulfur hexafluoride gas, a recovery unit 10 connected to the recovery unit, An acidic gas removing unit 20 for removing the acidic gas present in the sulfur fluoride gas, and an acidic gas removing unit 20 connected to the acidic gas removing unit 20 to pressurize or cool the waste gas hexafluoride gas from which the acidic gas has been removed, A first reactor 30 connected to the first reactor to form a hydrate of sulfur hexafluoride gas together with water; a hydrate of sulfur hexafluoride gas formed is connected to the first reactor 30 and is decompressed or raised to remove sulfur hexafluoride gas And a second reactor (40). In addition, the apparatus for separating and recovering sulfur hexafluoride gas may further include other structures as needed.

First, the recovery unit 10 recovers waste sulfur hexafluoride gas. At this time, the waste sulfur hexafluoride gas can recover the waste sulfur hexafluoride gas generated in the heavy electric power. More specifically, it is possible to recover the sulfur hexafluoride gas generated in the gas circuit breaker or the gas isolator. As the recovery unit, recovery suction or the like can be used.

The SF ₆ used in the heavy electric field is decomposed by arc discharge or the like under a high voltage to generate acid gases such as HF, SO ₂ , SOF _{2 and} SOF ₄ . In addition, N ₂ , O ₂ may exist due to external air inflow while recovering the sulfur hexafluoride gas from the heavy electric machine. Specifically lung SF6 gas is HF 10 to 10,000 ppmv, SO ₂ 10 to 1,000ppmv, SOF ₂ 10 to 5,000ppmv, SOF ₄ 10 to 1,000ppmv, N ₂ 0.1 to 5 vol%, O ₂ 0.1 to 5% by volume and an SF ₆ glass parts. In one embodiment of the present invention, impurity gases such as HF, SO ₂ , SOF _2, SOF _4, N ₂ and O ₂ are removed from the waste sulfur hexafluoride gas and pure SF ₆ is recovered.

Next, the acid gas removing unit 20 is connected to the recovery unit 10 and removes the acidic gas present in the waste sulfur hexafluoride gas recovered from the recovery unit 10.

As mentioned above, the pulverized sulfur hexafluoride gas generated in the heavy electric field contains acidic gases such as HF, SO ₂ , SOF _2, SOF ₄ and the like _, and therefore their removal is essential.

Conventionally, the pretreatment process for the acid gas is complicated and it is difficult to remove the inflow air (N ₂ , O ₂ ) during the recovery process. Therefore, the waste sulfur hexafluoride gas generated in the heavy electricity can not be re-injected into the production process of sulfur hexafluoride gas Sulfur hexafluoride was discarded or released into the atmosphere.

In the acidic gas removing unit 20, water containing an alkaline chemical such as NaOH or Ca (OH) ₂ is introduced into a separate inlet to remove the acidic gas, and the waste gas hexafluoride gas is cleaned, The adsorbent is introduced into a separate inlet to absorb the acid gas, and the acid gas is removed by a method of discharging the acid gas.

Next, the first reactor 30 is connected to the acid gas removing unit 20, and pressurizes or cools the sulfur hexafluorosulfide gas from which the acid gas has been removed, so that the hydrate of sulfur hexafluoride gas . At this time, the pressure may be 1 to 15 bar, and the temperature may be 0 to 10 ° C. In the above-mentioned range, the hydrate of sulfur hexafluoride gas is appropriately formed.

In the first reactor 30, the hydrate of sulfur hexafluoride gas is formed and the residual gas is removed. The residual gas means a gas such as N ₂ and O _{2 in} addition to the acid gas not removed from the acid gas removing unit 20.

The amount of water present in the first reactor 30 may be in the range of 210 to 250 parts by weight based on 100 parts by weight of pressurized, cooled, pulverized sulfur hexafluoride gas. If the amount of water is too small, there may arise a problem that not all of the hexafluorosulfur gas becomes hydrate. If the amount of water is too large, the amount of water that needs to be raised in temperature to recover SF ₆ increases and energy consumption may increase.

Water may contain additives to aid hydrate formation of sulfur hexafluoride gas. The additive may be an anionic surfactant, tetrahydrofuran or ammonium salt. More specifically, the anionic surfactant may be sodium dodecyl sulphate (SDS) or linear alkyl benzene sulphonate (LABS). The ammonium salt may be tetra-n-butyl ammonium bromide.

The anionic surfactant, tetrahydrofuran or ammonium salt may be added in an amount of 0.001 to 5% by weight based on 100% by weight of the aqueous solution. If the addition amount is too small, the effect of improving the hydrate formation rate may be insignificant. If the addition amount is too large, it may interfere with hydrate formation or may not be as effective as the amount of the added additive. Therefore, the addition amount can be adjusted within the above-mentioned range.

Some of the separated sulfur hexafluoride gas hydrate is introduced into the acidic gas removing unit 20 to remove the acidic gas again from the acidic gas removing unit 20 and then injected into the first reactor 30 to add sulfur hexafluoride As shown in FIG. Another part of the separated sulfur hexafluoride gas hydrate can be decomposed into SO ₂ and HF through the decomposition process.

The first reactor 30 is separated into an upper portion and a lower portion. The upper portion collects residual gas that has not been hydrated and discharges through the outlet, and the lower portion moves the hydrated liquid to the second reactor 40.

Next, the second reactor 40 is connected to the first reactor 30 to dissociate the hydrate of the sulfur hexafluoride gas formed in the first reactor 30, to remove water and recover the sulfur hexafluoride gas . In the second reactor (40), the temperature of the reactor can be adjusted to easily dissociate. Specifically, the temperature can be raised to 15 to 50 DEG C to dissociate the hydrate of sulfur hexafluoride gas. If the temperature falls outside the above range, dissociation is not smooth, so that the temperature can be controlled within the above-mentioned range.

When the hydrate of the sulfur hexafluoride gas dissociates into sulfur hexafluoride gas and water, there is a sulfur hexafluoride gas and moisture equivalent to the amount of saturated steam in the upper portion of the second reactor 40. At this time, water can be adsorbed and removed by using silica gel, molecular sieve or zeolite to remove moisture, and pure sulfur hexafluoride gas can be recovered. Specifically, a silica gel, a molecular sieve or a zeolite may be provided on the top of the water removing unit 50.

In the lower portion of the second reactor (40), water in which sulfur hexafluoride gas dissociates is collected. The collected water is again introduced into the first reactor 30 and can be used to form the hydrate of sulfur hexafluoride gas in the first reactor 30.

The recovered sulfur hexafluoride gas can be pressurized through the pressurizing portion to be charged in the heavy electricity. At this time, the pressure may be 2 to 5 bar. The pressurized sulfur hexafluoride gas may also be used to purge the first reactor 30 described above to remove the residual gas.

Hereinafter, preferred embodiments and comparative examples of the present invention will be described. However, the following examples are only a preferred embodiment of the present invention, and the present invention is not limited to the following examples.

Example

To recover the sulfur hexafluoride gas using hydrate, 170 mL of water injected with 0.3 wt% of SDBS (sodium dodecylbenzenesulfonate) was filled in a sealed 300 mL reactor, and the upper portion was filled with 99.8% sulfur hexafluoride gas.

The initial operation was carried out while gradually lowering the temperature at 15 ° C and 17.5 bar. The hydrate formation reactor formed hydrate as the pressure dropped to about 4 bar at 2 ° C. When the temperature was raised to 15 ° C without regulating the pressure to regenerate the formed hydrate, the hydrate formed disappeared and the initial temperature pressure of 15 ° C was recovered to the level of 17.5 bar. That is, almost all of the sulfur hexafluoride trapped on the hydrate phase could be recovered.

Comparative Example

Comparative Example was carried out in the same manner as in Example, but no water was added. As the temperature was lowered, the pressure was lowered to 2 캜 and decreased to 12.2 bar, but no hydrate was formed. When the temperature was raised to 15 ° C, the initial temperature was restored to 15.5 ° C, 17.5 bar.

FIG. 2 shows the temperature and pressure in the Examples and Comparative Examples with respect to time.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. As will be understood by those skilled in the art. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

10: recovery part 20: acid gas removal
30: first reactor 40: second reactor

Claims (22)

Recovering waste sulfur hexafluoride gas;
Removing the acidic gas present in the recovered sulfur hexafluorosulfur gas;
Pressurizing and cooling the waste gas hexafluoride gas from which the acid gas has been removed;
Adding water to the pressurized and cooled sulfur hexafluoride gas stream to form a hydrate of sulfur hexafluoride gas and removing the residual gas; And
Dissociating the hydrate of sulfur hexafluoride gas, and removing moisture to recover the hexafluorosulfur gas
And separating and recovering the sulfur hexafluoride gas. The method according to claim 1,
In the step of recovering the waste sulfur hexafluoride gas,
10 to 10,000 ppmv of HF, 10 to 1,000 ppmv of SO ₂ , 0.1 to 5% by volume of N ₂ , 10 to 5,000 ppmv of SOF ₂ , 10 to 1,000 ppmv of SOF ₄ , 0.1 to 5% by volume of O ₂ , parts of separation and recovery method of SF6 gas containing SF _6. 3. The method of claim 2,
In the step of removing the acid gas present in the recovered sulfur hexafluorosulfur gas,
Wherein the acidic gas is HF and SO ₂ , SOF ₂ , or SOF ₄ . The method according to claim 1,
The step of removing the acid gas present in the recovered sulfur hexafluorosulfur gas
NaOH or Ca (OH) ₂ to remove the acidic gas. The method according to claim 1,
The step of removing the acid gas present in the recovered sulfur hexafluorosulfur gas
A method for separating and recovering sulfur hexafluoride gas, wherein activated gas or molecular sieve is added to remove acid gas. The method according to claim 1,
The step of pressurizing and cooling the pulverized sulfur hexafluoride gas from which the acid gas has been removed
A method for separating and recovering sulfur hexafluoride gas in which acidic gas is removed and which is pressurized and cooled at a pressure of 1 to 15 bar and a temperature of 0 to 10 ° C. The method according to claim 1,
In the step of forming the hydrate of sulfur hexafluoride gas and removing the residual gas,
Wherein the residual gas comprises N ₂ and O ₂ . The method according to claim 1,
The step of forming the hydrate of sulfur hexafluoride gas and removing the residual gas
And adding 210 to 250 parts by weight of water to 100 parts by weight of the pressurized and cooled sulfur hexafluoride gas. The method according to claim 1,
A method for separating and recovering sulfur hexafluoride gas to which an anionic surfactant, a tetrahydrofuran or an ammonium salt is added to the water. 10. The method of claim 9,
Wherein said anionic surfactant is sodium dodecylsulfate or linear alkylbenzene sulfonate. 10. The method of claim 9,
Wherein said ammonium salt is tetrabutylammonium bromide. 10. The method of claim 9,
Wherein the anionic surfactant, tetrahydrofuran or ammonium salt is added in an amount of 0.001 to 5% by weight based on 100% by weight of the aqueous solution. The method according to claim 1,
And separating and recovering the sulfur hexafluoride gas dissociating the hydrate of the sulfur hexafluoride gas at a temperature of 15 to 50 캜. The method according to claim 1,
Further comprising the step of pressurizing the recovered sulfur hexafluoride gas to charge the heavy fuel cell. A recovery unit for recovering waste sulfur hexafluoride gas;
An acidic gas removal unit connected to the recovery unit and removing an acidic gas present in the recovered sulfur hexafluoride gas;
A first reactor connected to the acid gas removing unit to pressurize or cool the waste sulfur hexafluoride gas from which the acid gas has been removed to form a hydrate of sulfur hexafluoride gas together with the water contained therein; And
A second reactor connected to the first reactor for receiving the hydrate of the sulfur hexafluoride gas and decompressing or raising the temperature to dissociate and separate the hexafluorosulfur gas;
And separating and recovering the sulfur hexafluoride gas. 16. The method of claim 15,
Wherein the acidic gas removing unit is an apparatus for separating and recovering sulfur hexafluoride gas that is supplied with an aqueous solution containing NaOH or Ca (OH) ₂ to clean the sulfur hexafluoride gas. 16. The method of claim 15,
Wherein the acidic gas removing unit separates and recovers sulfur hexafluoride gas into which activated carbon or molecular sieve is charged. 16. The method of claim 15,
Wherein the first reactor is maintained at a pressure of 1 to 15 bar and a temperature of 0 to 10 < 0 > C. 16. The method of claim 15,
The first reactor is composed of an upper part and a lower part, and the upper part collects and discharges the residual gas including N ₂ and O ₂ , and the lower part collects the hydrated liquid and transfers the liquid to the second reactor A device for separating and recovering sulfur fluoride gas. 16. The method of claim 15,
And the second reactor is maintained at a temperature of 15 to 50 ° C. 16. The method of claim 15,
And an upper portion of the second reactor is provided with a silica gel, a molecular sieve or zeolite. 16. The method of claim 15,
Water separated from the sulfur hexafluoride gas is collected in the lower portion of the second reactor and the collected water is introduced into the first reactor to separate and recover the sulfur hexafluoride gas used for forming the hydrate of sulfur hexafluoride gas Device.

Images