CN110927295A - Long-term uninterrupted separation system for sulfide gas in GIS gas chamber - Google Patents
Long-term uninterrupted separation system for sulfide gas in GIS gas chamber Download PDFInfo
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- CN110927295A CN110927295A CN201911194918.3A CN201911194918A CN110927295A CN 110927295 A CN110927295 A CN 110927295A CN 201911194918 A CN201911194918 A CN 201911194918A CN 110927295 A CN110927295 A CN 110927295A
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- way valve
- carrier gas
- gas pipeline
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- gis
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- 238000000926 separation method Methods 0.000 title claims abstract description 42
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 title claims abstract description 19
- 230000007774 longterm Effects 0.000 title claims abstract description 19
- 239000007789 gas Substances 0.000 claims abstract description 68
- 239000012159 carrier gas Substances 0.000 claims abstract description 63
- 239000001307 helium Substances 0.000 claims abstract description 30
- 229910052734 helium Inorganic materials 0.000 claims abstract description 30
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims abstract description 28
- 230000004913 activation Effects 0.000 claims description 9
- 230000007613 environmental effect Effects 0.000 claims description 6
- 229910006095 SO2F Inorganic materials 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 5
- OBTWBSRJZRCYQV-UHFFFAOYSA-N sulfuryl difluoride Chemical compound FS(F)(=O)=O OBTWBSRJZRCYQV-UHFFFAOYSA-N 0.000 claims description 5
- 238000001514 detection method Methods 0.000 abstract description 11
- 230000008859 change Effects 0.000 abstract description 4
- 238000004587 chromatography analysis Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/04—Preparation or injection of sample to be analysed
- G01N30/06—Preparation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/62—Detectors specially adapted therefor
- G01N30/64—Electrical detectors
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
The invention provides a long-term uninterrupted separation system for sulfide gas in a GIS gas chamber, wherein a six-way valve of the system is connected with the GIS gas chamber, the six-way valve is connected to a ten-way valve A through a first quantitative pipe, and the six-way valve is connected to a ten-way valve B through a second quantitative pipe; the first carrier gas pipeline is connected to the first quantitative pipe through the ten-way valve A, the second carrier gas pipeline is sequentially connected with the ten-way valve A and the ten-way valve B, the third carrier gas pipeline is connected to the second quantitative pipe through the ten-way valve B, and the fourth carrier gas pipeline is connected to the temperature-controlled chromatographic column box; the ten-way valve A and the ten-way valve B are connected through a first communicating pipe and a second communicating pipe; the ten-way valve A is connected with the first chromatographic column, and the ten-way valve B is connected with the second chromatographic column and the helium ionization detector. The invention can carry out long-term uninterrupted separation detection on the detected gas, so that the components are mutually interfered, and the content change of the detected components is responded without distortion.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to a long-term uninterrupted separation system for sulfide gas in a GIS (gas insulated switchgear) gas chamber.
[ background of the invention ]
SF in GIS gas cell6Gas, under high-temperature and high-pressure discharge, produces SF6Decomposition products are respectively as follows: h2S、COS、SO2F2、SO2F、SO2Etc. by detecting SF since sulfide components are key to judging failure6Judging whether the power equipment has potential faults or not according to the content of the decomposition products, so as to prevent the generation of the faults;
the main problems of the existing chromatographic analysis are that sulfide components can not be completely analyzed, the components interfere with each other, the component content can not be accurately analyzed, and the like.
[ summary of the invention ]
The invention aims to solve the technical problem of providing a long-term uninterrupted separation system for sulfide gas in a GIS gas chamber, which can carry out long-term uninterrupted separation detection on detected gas, so that components are mutually interfered, and the undistorted response is realized on the content change of the detected components.
The invention is realized by the following steps:
a long-term uninterrupted separation system for sulfide gas in a GIS gas chamber comprises an air-isolated carrier gas device, a central separation device, a gas supply device, a temperature-controlled chromatographic column box and a helium ionization detector,
the air-isolated type carrier gas device comprises a six-way valve, a first quantitative pipe and a second quantitative pipe, the central separation device comprises a ten-way valve A and a ten-way valve B, the gas supply device comprises a gas supply bottle group, a first carrier gas pipeline, a second carrier gas pipeline, a third carrier gas pipeline and a fourth carrier gas pipeline, the first carrier gas pipeline, the second carrier gas pipeline, the third carrier gas pipeline and the fourth carrier gas pipeline are connected with the gas supply bottle group, and the temperature control chromatographic column box comprises a first chromatographic column and a second chromatographic column;
the six-way valve is connected with the GIS air chamber, the six-way valve is connected to the ten-way valve A through a first quantitative pipe, and the six-way valve is connected to the ten-way valve B through a second quantitative pipe; the first carrier gas pipeline is connected to the first quantitative tube through a ten-way valve A, the second carrier gas pipeline is sequentially connected with the ten-way valve A and a ten-way valve B, the third carrier gas pipeline is connected to the second quantitative tube through the ten-way valve B, and the fourth carrier gas pipeline is connected to the temperature-controlled chromatographic column box; the ten-way valve A and the ten-way valve B are connected through a first communicating pipe and a second communicating pipe; the ten-way valve A is connected with the first chromatographic column, and the ten-way valve B is connected with the second chromatographic column and the helium ionization detector.
Further, the first chromatographic column environmental parameter is: column temperature 80 °, flow rate 15ml/min, fraction separation: h2S、COS、SO2F2、SO2F;
The second chromatographic column environmental parameters are as follows: column temperature 40 °, flow rate 5ml/min, fraction separation: SO (SO)2。
Further, the helium ionization detector is a PDD detector.
Furthermore, the gas cylinder group comprises a helium gas cylinder group and an air cylinder group, the helium gas cylinder group comprises a plurality of helium gas cylinders connected in series, the air cylinder group comprises at least one air cylinder, the helium gas cylinder group is connected with the first carrier gas pipeline, the second carrier gas pipeline and the third carrier gas pipeline, and the air cylinder group is connected with the fourth carrier gas pipeline.
Further, when the separation system starts the activation treatment, the first chromatographic column and the second chromatographic column output air flow rate of 0.5MPa and 50ml/min under the control of the air bottle group, and the temperature is controlled to carry out the activation of the chromatographic columns by the temperature rise process of 50-300 ℃.
The invention has the following advantages:
the invention utilizes the switching of various valves and the separation action of the chromatographic column on the detection sample, can carry out uninterrupted separation detection on the sulfide gas in the GIS gas chamber, and can respond the content and the change of the components of the detected object without distortion; and when the performance of the chromatographic column is reduced, activation treatment can be carried out to achieve the performance resetting effect, and high-response separation and long-term separation detection of the components of the sample to be detected are realized.
[ description of the drawings ]
The invention will be further described with reference to the following examples with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a sampling circuit for a long term uninterrupted separation system of sulfide gas in a GIS gas chamber according to the present invention.
FIG. 2 is a schematic diagram of a first chromatographic column sample injection circuit of a long-term uninterrupted separation system for sulfide gas in a GIS gas chamber.
FIG. 3 is a schematic diagram of a second chromatographic column sample injection circuit of a long-term uninterrupted separation system for sulfide gas in a GIS gas chamber.
The reference numbers are as follows:
1-temperature control chromatographic column box, 2-helium ionization detector, 3-six-way valve, 4-first quantitative tube, 5-second quantitative tube, 6-ten-way valve A, 7-ten-way valve B, 8-gas supply bottle group, 9-first carrier gas pipeline, 10-second carrier gas pipeline, 11-third carrier gas pipeline, 12-fourth carrier gas pipeline, 13, first chromatographic column, 14-second chromatographic column, 15-first communicating pipe, 16-second communicating pipe, 81-helium bottle group and 82-air bottle group
[ detailed description ] embodiments
Referring to fig. 1-3, the invention relates to a long-term uninterrupted separation system for sulfide gas in a GIS gas chamber, which comprises an air-isolated carrier gas device, a central separation device, a gas supply device, a temperature-controlled chromatographic column box 1 and a helium ionization detector 2,
the air-isolated carrier gas device comprises a six-way valve 3, a first quantitative pipe 4 and a second quantitative pipe 5, the central separation device comprises a ten-way valve A6 and a ten-way valve B7, the gas supply device comprises a gas supply bottle group 8, a first carrier gas pipeline 9, a second carrier gas pipeline 10, a third carrier gas pipeline 11 and a fourth carrier gas pipeline 12 which are connected with the gas supply bottle group 8, and the temperature-controlled chromatographic column box 1 comprises a first chromatographic column 13 and a second chromatographic column 14;
the six-way valve 3 is connected with the GIS air chamber, the six-way valve 3 is connected to the ten-way valve A6 through a first quantitative pipe 4, and the six-way valve 3 is connected to the ten-way valve B7 through a second quantitative pipe 5; the first carrier gas pipeline 9 is connected to the first quantitative tube 4 through a ten-way valve A6, the second carrier gas pipeline 10 is sequentially connected with the ten-way valve A6 and a ten-way valve B7, the third carrier gas pipeline 11 is connected to the second quantitative tube 5 through the ten-way valve B7, and the fourth carrier gas pipeline 12 is connected to the temperature-controlled chromatographic column box 1; the ten-way valve A6 is connected with the ten-way valve B7 through a first communicating pipe 15 and a second communicating pipe 16; the ten-way valve A6 is connected with the first chromatographic column 13, and the ten-way valve B7 is connected with the second chromatographic column 14 and the helium ionization detector 2.
The first chromatographic column 13 environmental parameters: column temperature 80 °, flow rate 15ml/min, fraction separation: h2S、COS、SO2F2、SO2F;
Environmental parameters of the second chromatography column 14: column temperature 40 °, flow rate 5ml/min, fraction separation: SO (SO)2。
The helium ionization detector 2 is a PDD detector.
The gas cylinder group 8 comprises a helium gas cylinder group 81 and an air cylinder group 82, the helium gas cylinder group 81 comprises a plurality of helium gas cylinders connected in series, the air cylinder group 82 comprises at least one air cylinder, the helium gas cylinder group 81 is connected with a first carrier gas pipeline 9, a second carrier gas pipeline 10 and a third carrier gas pipeline 11, and the air cylinder group 82 is connected with a fourth carrier gas pipeline 12.
When the separation system starts the activation treatment, the first chromatographic column 13 and the second chromatographic column 14 control and output air flow rate of 0.5MPa and 50ml/min through the air bottle group 82, and the temperature is controlled to carry out chromatographic column activation by the temperature rise process of 50-300 ℃.
The working process of the invention is as follows:
step 1, referring to fig. 1, when sampling is performed: gas in the GIS gas chamber sequentially passes through the ports 2 and 3 of the six-way valve 3, the ports 3 and 2 of the ten-way valve A6, the first quantitative pipe 4, the ports 5 and 4 of the ten-way valve A6, the ports 3 and 2 of the ten-way valve B7, the second quantitative pipe 5 and the ports 5 and 4 of the ten-way valve B7, finally returns to the port 6 of the six-way valve 3, is discharged through the port 1 of the six-way valve 3, and when the first quantitative pipe 4 and the second quantitative pipe 5 are filled with samples, the six-way valve 3 switches valve ports to cut off gas and isolate air;
And finally, combining the detection results of the two times to obtain the component content of the sample to be detected.
And continuously circulating the steps.
When the system is in sampling operation, the second carrier gas pipeline 10 is sequentially connected with the ports 8 and 9 of the ten-way valve A6 and the ports 8 and 9 of the ten-way valve B7, and is finally connected to the PDD detector; when the ten-way valve A6 is in sample injection operation, the second carrier gas conduit 10 is connected to the 8 port of the ten-way valve A6 and directly evacuated through the 7 port of the ten-way valve A6.
When the chromatographic column needs to be activated, the air bottle group 82 is adjusted to control and output the air flow rate of 0.5MPa and 50ml/min, the first chromatographic column 13 and the second chromatographic column 14 of the temperature-controlled chromatographic column box 1 are supplied with air through the fourth carrier gas pipeline 12, and the temperature is controlled to carry out the chromatographic column activation through the temperature rise process of 50-300 ℃.
The invention utilizes the switching of various valves and the separation action of the chromatographic column on the detection sample, can carry out uninterrupted separation detection on the sulfide gas in the GIS gas chamber, and can respond the content and the change of the components of the detected object without distortion; and when the performance of the chromatographic column is reduced, activation treatment can be carried out to achieve the performance resetting effect, and high-response separation and long-term separation detection of the components of the sample to be detected are realized.
Although specific embodiments of the invention have been described above, it will be understood by those skilled in the art that the specific embodiments described are illustrative only and are not limiting upon the scope of the invention, and that equivalent modifications and variations can be made by those skilled in the art without departing from the spirit of the invention, which is to be limited only by the appended claims.
Claims (5)
1. A long-term uninterrupted separation system for sulfide gas in a GIS gas chamber is characterized in that: the system comprises an air-isolated carrier gas device, a central separation device, a gas supply device, a temperature-controlled chromatographic column box and a helium ionization detector,
the air-isolated type carrier gas device comprises a six-way valve, a first quantitative pipe and a second quantitative pipe, the central separation device comprises a ten-way valve A and a ten-way valve B, the gas supply device comprises a gas supply bottle group, a first carrier gas pipeline, a second carrier gas pipeline, a third carrier gas pipeline and a fourth carrier gas pipeline, the first carrier gas pipeline, the second carrier gas pipeline, the third carrier gas pipeline and the fourth carrier gas pipeline are connected with the gas supply bottle group, and the temperature control chromatographic column box comprises a first chromatographic column and a second chromatographic column;
the six-way valve is connected with the GIS air chamber, the six-way valve is connected to the ten-way valve A through a first quantitative pipe, and the six-way valve is connected to the ten-way valve B through a second quantitative pipe; the first carrier gas pipeline is connected to the first quantitative tube through a ten-way valve A, the second carrier gas pipeline is sequentially connected with the ten-way valve A and a ten-way valve B, the third carrier gas pipeline is connected to the second quantitative tube through the ten-way valve B, and the fourth carrier gas pipeline is connected to the temperature-controlled chromatographic column box; the ten-way valve A and the ten-way valve B are connected through a first communicating pipe and a second communicating pipe; the ten-way valve A is connected with the first chromatographic column, and the ten-way valve B is connected with the second chromatographic column and the helium ionization detector.
2. The system of claim 1 for long term uninterrupted separation of sulphide gases in a GIS chamber, wherein: the first chromatographic column environmental parameter: column temperature 80 °, flow rate 15ml/min, fraction separation: h2S、COS、SO2F2、SO2F;
The second chromatographic column environmental parameters are as follows: column temperature 40 °, flow rate 5ml/min, fraction separation: SO (SO)2。
3. The system of claim 1 for long term uninterrupted separation of sulphide gases in a GIS chamber, wherein: the helium ionization detector is a PDD detector.
4. The system of claim 1 for long term uninterrupted separation of sulphide gases in a GIS chamber, wherein: the gas cylinder group comprises a helium gas cylinder group and an air cylinder group, the helium gas cylinder group comprises a plurality of helium gas cylinders connected in series, the air cylinder group comprises at least one air cylinder, the helium gas cylinder group is connected with a first carrier gas pipeline, a second carrier gas pipeline and a third carrier gas pipeline, and the air cylinder group is connected with a fourth carrier gas pipeline.
5. The system of claim 4 for long term uninterrupted separation of sulphide gases in a GIS gas chamber, wherein: when the separation system starts the activation treatment, the first chromatographic column and the second chromatographic column output air flow rate of 0.5MPa and 50ml/min under the control of the air bottle group, and the temperature is controlled to carry out the activation of the chromatographic columns by the temperature rise process of 50-300 ℃.
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Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102353737A (en) * | 2011-08-26 | 2012-02-15 | 广东电网公司电力科学研究院 | Detection device for detecting sulfur hexafluoride electrical equipment fault gas |
CN202305489U (en) * | 2011-11-07 | 2012-07-04 | 福建亿榕信息技术有限公司 | Chromatographic instrument for detecting failure of SF6 electric equipment |
CN104155402A (en) * | 2014-08-27 | 2014-11-19 | 上海华爱色谱分析技术有限公司 | Helium ionization gas chromatography system for analyzing decomposition products of SF6 |
CN104198638A (en) * | 2014-08-20 | 2014-12-10 | 国家电网公司 | Chromatographic analysis system and method for detecting sulfur hexafluoride decomposition products |
CN104849376A (en) * | 2015-06-15 | 2015-08-19 | 国网山西省电力公司电力科学研究院 | Chromatographic test device capable of prolonging lifespan of chromatographic column and test method thereof |
US20190107517A1 (en) * | 2016-10-31 | 2019-04-11 | Electric Power Research Institute Of Guangdong Power Grid Co., Ltd. | Refilling-type online chromatographic detector for sulphur hexafluoride decomposition products |
CN211652717U (en) * | 2019-11-28 | 2020-10-09 | 福建亿榕信息技术有限公司 | Long-term uninterrupted separation system for sulfide gas in GIS gas chamber |
-
2019
- 2019-11-28 CN CN201911194918.3A patent/CN110927295A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102353737A (en) * | 2011-08-26 | 2012-02-15 | 广东电网公司电力科学研究院 | Detection device for detecting sulfur hexafluoride electrical equipment fault gas |
CN202305489U (en) * | 2011-11-07 | 2012-07-04 | 福建亿榕信息技术有限公司 | Chromatographic instrument for detecting failure of SF6 electric equipment |
CN104198638A (en) * | 2014-08-20 | 2014-12-10 | 国家电网公司 | Chromatographic analysis system and method for detecting sulfur hexafluoride decomposition products |
CN104155402A (en) * | 2014-08-27 | 2014-11-19 | 上海华爱色谱分析技术有限公司 | Helium ionization gas chromatography system for analyzing decomposition products of SF6 |
CN104849376A (en) * | 2015-06-15 | 2015-08-19 | 国网山西省电力公司电力科学研究院 | Chromatographic test device capable of prolonging lifespan of chromatographic column and test method thereof |
US20190107517A1 (en) * | 2016-10-31 | 2019-04-11 | Electric Power Research Institute Of Guangdong Power Grid Co., Ltd. | Refilling-type online chromatographic detector for sulphur hexafluoride decomposition products |
CN211652717U (en) * | 2019-11-28 | 2020-10-09 | 福建亿榕信息技术有限公司 | Long-term uninterrupted separation system for sulfide gas in GIS gas chamber |
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