CN214486772U - Device for preparing heptafluoroisobutyronitrile mixed gas - Google Patents
Device for preparing heptafluoroisobutyronitrile mixed gas Download PDFInfo
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- CN214486772U CN214486772U CN202120296147.5U CN202120296147U CN214486772U CN 214486772 U CN214486772 U CN 214486772U CN 202120296147 U CN202120296147 U CN 202120296147U CN 214486772 U CN214486772 U CN 214486772U
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Abstract
The utility model provides a device of seven fluorine isobutyronitrile mist configurations, first check valve 1, second check valve 2, first governing valve, second governing valve, buffer tank, first pressure regulator, second pressure regulator, first flowmeter, second flowmeter, first solenoid valve, gas mixing tank, second solenoid valve, vacuum pump, high accuracy manometer and control module. The utility model provides a device of seven fluorine isobutyronitrile mist configurations adjusts when relying on governing valve, pressostat and flowmeter through the flowmeter of high accuracy to seven fluorine isobutyronitrile and the accurate measurement of low boiling point gas to realize more accurate, constrictive regulation gradient, improved the accuracy of seven fluorine isobutyronitrile mist configurations, can be fine satisfy the requirement of electrical equipment to mist mixing ratio precision.
Description
Technical Field
The utility model belongs to the technical field of the mist disposes, especially, relate to a device of seven fluorine isobutyronitrile mist disposes suitable for electrical equipment.
Background
Sulfur hexafluoride (SF)6) The gas has excellent insulation and arc extinguishing performance, and is widely applied to high-voltage electrical equipment such as circuit breakers, Gas Insulated Switches (GIS), gas insulated transmission lines (GIL) and the like, and ring main units of industrial and mining enterprises and user sides. But SF6The Global Warming Potential (GWP) of gas is about CO222800 times of the total amount of the active carbon, the life of the active carbon in the atmosphere is as long as 3200 years, and the active carbon has great influence on the environment. In 1997, the book of the Kyoto protocol shall SF6Listed as one of the 6 greenhouse gases that limit emissions. Thereby, SF6The environmental problems caused by the prior art are of great concern, and the need to substitute SF is urgently needed6Is environmentally friendly.
It has been found that heptafluoroisobutyronitrile (hereinafter referred to as "C")4F7N') has excellent insulating and environmental properties, C4F7The GWP of N is 2100, and the insulating property is SF under the same air pressure62 times of the prior insulating gas, is a new generation of environment-friendly insulating gas with the most application prospect. However, C4F7The boiling point of N is higher, namely-4.7 ℃, and the N is easy to liquefy when used in cold regions, thereby affecting the insulating property of the N. Thus, C4F7The application range of N directly as an insulating gas is greatly limited. Nitrogen (N)2) And carbon dioxide (CO)2) And C4F7N has synergistic effect and can be used as low boiling pointA dilution gas of the dots. Especially C4F7N and CO2The binary mixed gas can effectively reduce carbon deposition in the process of electrolysis, and is generally considered to be a better choice.
However, no industrial application report exists on the heptafluoroisobutyronitrile mixed gas configuration device, and the existing mixed gas configuration device cannot be directly used, on one hand, the existing mixed gas configuration device usually adopts a method of respectively metering two gases and sequentially introducing the two gases, so that the gases are easily mixed unevenly, and the gas mixer needs to be placed for a long time or added to ensure the even mixing of the gases; on the other hand, the boiling point of heptafluoroisobutyronitrile is high, and when the flow rate is high, liquefaction is easy to occur, so that the metering accuracy is influenced, and C is in the preparation process4F7The accurate measurement of N and low boiling point diluent gas directly influences the application performance of the mixed gas, and further influences the reliability of the operation of power equipment. Thus, development of C4F7N mixed gas configuration devices have an urgent need for propelling C4F7The N replaces the process, and has important significance for accelerating the environmental protection construction of the power grid in China.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to solve the technical problem in the above-mentioned background, provide a device of seven fluorine isobutyronitrile and carbon dioxide nitrogen gas binary mixed gas configuration, the utility model discloses not only can satisfy the accuracy requirement and the insulating properties requirement of electrical equipment to seven fluorine isobutyronitrile binary mixed gas mixing ratio, pressure, have easy and simple to handle, the advantage that the operation is stable moreover.
The technical scheme of the utility model as follows:
the utility model provides a device of seven fluorine isobutyronitrile mist configurations, includes a gas mixing tank, be connected with seven fluorine isobutyronitrile inlet line, the dilute gas inlet line and the high accuracy manometer of taking the second check valve of taking first check valve on the gas mixing tank, its characterized in that:
the heptafluoroisobutyronitrile air inlet pipeline is sequentially connected with a first one-way valve, a first regulating valve, a buffer tank, a first barostat and a first flowmeter;
the dilution gas inlet pipeline is sequentially connected with a second one-way valve, a second regulating valve, a second constant pressure device and a second flowmeter; the first one-way valve is communicated with an external heptafluoroisobutyronitrile storage tank, the second one-way valve is communicated with an external diluent gas storage tank, the outlet end of the second flowmeter and the outlet end of the first flowmeter are communicated with a gas inlet of the gas mixing tank, and the gas inlet is connected with a first electromagnetic valve.
The first and second flow meters are mass flow meters.
The first and second flow meters are coriolis mass flow meters.
The buffer tank is internally provided with a baffle plate to increase C4F7N flow resistance, C liquefied at an excessive flow rate4F7N is completely vaporized in the buffer tank.
The outlet end of the first regulating valve is communicated with the bottom of the buffer tank, and the top of the buffer tank is communicated with the inlet end of the first barostat.
And the gas mixing tank is also connected with a gas emptying pipeline.
The gas evacuation pipeline is sequentially connected with a second electromagnetic valve and a vacuum pump.
The device for configuring the heptafluoroisobutyronitrile mixed gas further comprises a control module, wherein the control module is electrically connected with the first regulating valve, the second regulating valve, the first barostat, the second barostat, the first flowmeter, the second flowmeter, the first electromagnetic valve, the second electromagnetic valve and the high-precision electric power meter.
The control module comprises a parameter setting unit, an information collecting unit and an instruction issuing unit; the parameter setting unit realizes the configuration of the mixing ratio of the heptafluoroisobutyronitrile mixed gas and the numerical value input of the total gas amount; the information collection unit collects pressure data of the gas mixing tank and flow data of the first flow meter and the second flow meter; the instruction issuing unit processes the real-time information to realize automatic adjustment of the first regulating valve, the second regulating valve, the first barostat, the second barostat, the first flowmeter, the second flowmeter and the first electromagnetic valve.
The first regulating valve and the second regulating valve are provided with 100 percent and 50 percentFour gears of 20% and 0%, the gears decrease as the total flow of gas increases. I.e. C4F7When the total flow of N reaches 50% of a set value, the gear of the first regulating valve is 50%; c4F7When the total flow of N reaches 80% of a set value, the gear of the first regulating valve is 20%; c4F7When the total flow of N reaches a set value, the gear of the first regulating valve is 0%. Low boiling point diluent gas CO2/N2When the total flow reaches 50% of the set value, the gear of the first regulating valve is 50%; c4F7When the total flow of N reaches 80% of a set value, the gear of the first regulating valve is 20%; c4F7When the total flow of N reaches a set value, the gear of the first regulating valve is 0%.
The first constant pressure device and the second constant pressure device can respectively realize pressure adjustment of the inlet ends of the first flowmeter and the second flowmeter, and the pressure difference between the inlet ends and the outlet ends of the first flowmeter and the second flowmeter is kept relatively stable.
The utility model has the advantages that: the utility model provides a device of seven fluorine isobutyronitrile mist configurations adjusts when relying on governing valve, pressostat and flowmeter through the flowmeter of high accuracy to seven fluorine isobutyronitrile and the accurate measurement of low boiling point gas to realize more accurate, constrictive regulation gradient, improve the accuracy of seven fluorine isobutyronitrile mist configurations, can be fine satisfy the requirement of electrical equipment to seven fluorine isobutyronitrile mist mixing ratio precision.
Drawings
Fig. 1 is a schematic structural diagram of a device for distributing a heptafluoroisobutyronitrile mixed gas according to the present invention.
The direction of the arrows in the figure is the direction of gas travel.
Detailed Description
The invention will be described in further detail with reference to the following description and embodiments, which are not intended to limit the invention, but rather should be construed broadly within its scope and limited only by the appended claims, as modifications and variations thereof may be made by those skilled in the art without departing from the spirit of the invention.
As shown in fig. 1, the device for configuring heptafluoroisobutyronitrile mixed gas of the present invention comprises a gas mixing tank 11 and a control module 50, wherein the gas mixing tank 11 is connected with a heptafluoroisobutyronitrile inlet pipeline 20, a diluent gas inlet pipeline 30, a gas evacuation pipeline 40 and a high precision pressure gauge 14;
the heptafluoroisobutyronitrile air inlet pipeline 20 is sequentially connected with a first one-way valve 1, a first regulating valve 3, a buffer tank 5, a first constant pressure device 6 and a first flowmeter 8; the first regulating valve 3, the first constant pressure device 6 and the first flow meter 8 are electrically connected with the control module 50;
the dilution gas inlet pipeline 30 is sequentially connected with a second one-way valve 2, a second regulating valve 4, a second barostat 7 and a second flowmeter 9; the second regulating valve 4, the second constant pressure device 7 and the second flow meter 9 are electrically connected with the control module 50;
the first check valve 1 is communicated with an external heptafluoroisobutyronitrile storage tank, the second check valve 2 is communicated with an external diluent gas storage tank, the outlet end of the second flowmeter 9 and the outlet end of the first flowmeter 8 are communicated with a gas inlet 15 of the gas mixing tank 11, the gas inlet 15 is connected with a first electromagnetic valve 10, and the first electromagnetic valve 10 is electrically connected with the control module 50.
Preferably the first flow meter 8 and the second flow meter 9 are coriolis mass flow meters; the buffer tank is internally provided with a baffle plate to increase C4F7N flow resistance, C liquefied at an excessive flow rate4F7N is completely vaporized in the buffer tank.
The outlet end of the first regulating valve 3 is communicated with the bottom of the buffer tank 5, and the top of the buffer tank 5 is communicated with the inlet end of the first pressostat 6.
The gas evacuation pipeline 40 is sequentially connected with a second electromagnetic valve 12 and a vacuum pump 13, and the second electromagnetic valve 12 is electrically connected with the control module 50.
The control module 50 is electrically connected to the high-precision power meter 14.
The control module 50 comprises a parameter setting unit, an information collecting unit and an instruction issuing unit; the parameter setting unit realizes the configuration of the mixing ratio of the heptafluoroisobutyronitrile mixed gas and the numerical value input of the total gas amount; the information collection unit collects pressure data of the gas mixing tank 11 and flow rate data of the first flow meter 8 and the second flow meter 9; the instruction issuing unit processes the real-time information to realize automatic adjustment of the first regulating valve 3, the second regulating valve 4, the first barostat 6, the second barostat 7, the first flowmeter 8, the second flowmeter 9, the first electromagnetic valve 10 and the second electromagnetic valve 12.
The first regulating valve 10 and the second regulating valve 12 are provided with four gears of 100%, 50%, 20% and 0%.
The diluent gas may be carbon dioxide or nitrogen, or a mixture of carbon dioxide and nitrogen.
The utility model provides a device of seven fluorine isobutyronitrile mist configurations, detailed operating procedure is as follows:
turning on the vacuum pump, inputting the parameters of the heptafluoroisobutyronitrile mixed gas including the mixing ratio and the total amount of the gas, and automatically calculating C by the system4F7N and low boiling point diluent gas CO2/N2And (3) starting clicking according to the total flow, adjusting the first regulating valve 3 and the second regulating valve 4 to be in 100% gear positions by the control module, opening the first electromagnetic valve 10 and the second electromagnetic valve 12, and pumping residual gas in the device away by the vacuum pump 13. And after the pressure in the device is qualified, the second electromagnetic valve 12 is closed.
Opening C4F7N gas cylinder valve, C4F7The N gas enters a gas mixing tank 11, C through a first one-way valve 1, a first regulating valve 3, a buffer tank 5, a first constant pressure device 6, a first flowmeter 8 and a first electromagnetic valve 104F7When the total flow of N reaches 50% of the set value, the gear of the first regulating valve 3 is 50%; c4F7When the total flow of N reaches 80% of the set value, the gear of the first regulating valve 3 is 20%; c4F7When the total flow of N reaches the set value, the gear of the first regulating valve 3 is 0%. Meanwhile, the first constant pressure device 6 keeps the pressure difference between the inlet and the outlet of the first flowmeter 8 at 0.08-0.1MPa, and the first flowmeter 8 follows C4F7The total flow of N is gradually reduced as the total flow of N is increased.
While simultaneously opening the low boiling point diluent gas CO2/N2Cylinder valve, CO2/N2The gas enters a gas mixing tank 11 through a second one-way valve 2, a second regulating valve 4, a second constant pressure device 7, a second flowmeter 9 and a first electromagnetic valve 10, and CO is mixed2/N2When the total gas flow reaches 50% of the set value, the gear of the second regulating valve 4 is 50%; CO 22/N2When the total gas flow reaches 80% of the set value, the gear of the second regulating valve 4 is 20%; CO 22/N2When the total gas flow reaches the set value, the gear of the second regulating valve 4 is 0%. Meanwhile, the second constant pressure device 7 keeps the pressure difference between the inlet and the outlet of the second flowmeter 9 at 0.08-0.1MPa, and the second flowmeter 9 follows CO2/N2The total flow of gas becomes larger and gradually decreases.
And (4) after the gas is configured, closing the first electromagnetic valve 10, analyzing the configured heptafluoroisobutyronitrile mixed gas, and detecting the mixed gas mixing ratio.
Example 1
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (2.0%) and carbon dioxide (98.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas preparation was completed, the mixed gas composition was checked by chromatography, and the analysis results are shown in table 1.
Example 2
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (4.0%) and carbon dioxide (96.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas preparation was completed, the mixed gas composition was checked by chromatography, and the analysis results are shown in table 1.
Example 3
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (6.0%) and carbon dioxide (94.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas preparation was completed, the mixed gas composition was checked by chromatography, and the analysis results are shown in table 1.
Example 4
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (8.0%) and carbon dioxide (92.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas is prepared, the composition of the mixed gas is detected by chromatography, and the analysis result is shown in table 1
Example 5
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (10.0%) and carbon dioxide (90.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas is prepared, the composition of the mixed gas is detected by chromatography, and the analysis result is shown in table 1
Example 6
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (14.0%) and carbon dioxide (86.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas preparation was completed, the mixed gas composition was checked by chromatography, and the analysis results are shown in table 1.
Example 7
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (18.0%) and carbon dioxide (82.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas preparation was completed, the mixed gas composition was checked by chromatography, and the analysis results are shown in table 1.
Example 8
The flow meters in the gas distribution device all adopt Coriolis mass flow meters, mixed gas consisting of heptafluoroisobutyronitrile (20.0%) and carbon dioxide (80.0%) is configured according to the operation steps, and the total amount of the mixed gas is 10L. After the mixed gas preparation was completed, the mixed gas composition was checked by chromatography, and the analysis results are shown in table 1.
The chromatographic analysis method of the composition of the mixed gas comprises the following steps:
and connecting the gas mixing tank with a sample injector, connecting the sample injector with a chromatograph, and connecting the sample injector with a vacuum pump. Before sample introduction, the vacuum pump pumps the connecting pipeline to a vacuum state, the valve of the gas mixing tank is opened, the configured mixed gas is introduced to flush the pipeline, and the operation is repeated for more than 3 times. After the flushing is finished, the mixed gas in the gas mixing pipe is injected into a sample injection pipeline of a chromatographic instrument through a sample injector, the gas is separated through a chromatographic column and detected through a TCD detector, and the content of each component in the mixed gas is tested according to the area of a signal peak. Taking the test of the mixed gas of heptafluoroisobutyronitrile and carbon dioxide as an example, the calculation formula is as follows:
nC4F7N：nCO2＝(AC4F7N×fC4F7N)：(ACO2×fCO2)
wherein n isC4F7NAnd nCO2Represents the molar amounts of heptafluoroisobutyronitrile and carbon dioxide, AC4F7NAnd ACO2Area of signal peaks representing heptafluoroisobutyronitrile and carbon dioxide, fC4F7NAnd fCO2Relative correction factors for heptafluoroisobutyronitrile and carbon dioxide are expressed by internal standard method.
TABLE 1
It can be seen from the above result that the utility model provides a device for configuration of heptafluoro isobutyronitrile mist has higher precision, can satisfy the required precision of power equipment to the mist mixing ratio.
Claims (10)
1. The utility model provides a device of seven fluorine isobutyronitrile mist configurations, includes a gas mixing tank, be connected with seven fluorine isobutyronitrile inlet line, the dilute gas inlet line and the high accuracy manometer of taking the second check valve of taking first check valve on the gas mixing tank, its characterized in that: the heptafluoroisobutyronitrile air inlet pipeline is sequentially connected with a first one-way valve, a first regulating valve, a buffer tank, a first barostat and a first flowmeter;
the dilution gas inlet pipeline is sequentially connected with a second one-way valve, a second regulating valve, a second constant pressure device and a second flowmeter;
the first one-way valve is communicated with an external heptafluoroisobutyronitrile storage tank, the second one-way valve is communicated with an external diluent gas storage tank, the outlet end of the second flowmeter and the outlet end of the first flowmeter are communicated with a gas inlet of the gas mixing tank, and the gas inlet is connected with a first electromagnetic valve.
2. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 1, wherein: the first and second flow meters are mass flow meters.
3. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 2, wherein: the first and second flow meters are coriolis mass flow meters.
4. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 1, wherein: a baffle is arranged in the buffer tank.
5. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 4, wherein: the outlet end of the first regulating valve is communicated with the bottom of the buffer tank, and the top of the buffer tank is communicated with the inlet end of the first barostat.
6. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 1, wherein: and the gas mixing tank is also connected with a gas emptying pipeline.
7. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 6, wherein: the gas evacuation pipeline is sequentially connected with a second electromagnetic valve and a vacuum pump.
8. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 7, wherein: the device also comprises a control module which is electrically connected with the first regulating valve, the second regulating valve, the first barostat, the second barostat, the first flowmeter, the second flowmeter, the first electromagnetic valve, the second electromagnetic valve and the high-precision electric power meter.
9. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 8, wherein: the control module comprises a parameter setting unit, an information collecting unit and an instruction issuing unit; the parameter setting unit realizes the configuration of the mixing ratio of the heptafluoroisobutyronitrile mixed gas and the numerical value input of the total gas amount; the information collection unit collects pressure data of the gas mixing tank and flow data of the first flow meter and the second flow meter; the instruction issuing unit processes the real-time information to realize automatic adjustment of the first regulating valve, the second regulating valve, the first barostat, the second barostat, the first flowmeter, the second flowmeter, the first electromagnetic valve and the second electromagnetic valve.
10. The apparatus for preparing a heptafluoroisobutyronitrile mixed gas according to claim 1, wherein: the first regulating valve and the second regulating valve are provided with four gears of 100%, 50%, 20% and 0%.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202120296147.5U CN214486772U (en) | 2021-02-02 | 2021-02-02 | Device for preparing heptafluoroisobutyronitrile mixed gas |
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| CN202120296147.5U CN214486772U (en) | 2021-02-02 | 2021-02-02 | Device for preparing heptafluoroisobutyronitrile mixed gas |
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