Plasma insulation oil chromatographic analysis device and method with automatic calibration function

Abstract

The application provides a kind of plasma insulating oil chromatographic analysis device and method with automatic calibration function, the application first uses high concentration gas to flush pipeline, exclude the interference of residual gas in pipeline, and make circulating pipeline rapidly adsorb a large amount of impurity gas, so that the adsorption amount reaches or exceeds the adsorption saturation amount under the calibration concentration, then the calibration concentration gas is passed in for 10 min to make the pipeline adsorb saturated under the concentration, ensure that the gas concentration value analyzed is the label value, improve the reliability of calibration result, so as to improve the analysis and detection precision.The application can dilute the bottle gas with known concentration through two buffer tanks according to pressure, and automatically prepare calibration gas containing impurity gas with different concentrations.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of insulating oil chromatographic analysis, in particular to an insulating oil chromatographic analysis device and method with automatic calibration function. BACKGROUND

[0002] The enhanced insulating oil chromatograph needs to be calibrated frequently to ensure the reliability of detection results. The existing calibration method directly introduces a standard gas containing a known concentration into the chromatograph, and the chromatograph completes the calibration work at the concentration. Although the gas flow pipeline currently adopted is mostly subjected to acid pickling, passivation and polishing treatment, thereby effectively reducing the adsorption of the inner wall of the pipeline to the gas. However, when the enhanced insulating oil chromatograph detects the transformer insulating oil, the concentrations of the seven kinds of impurity gases (CH4, C2H2, C2H4, C2H6, H2, CO and CO2) may be as low as 10 -6 ~ 10 -9 Therefore, the impurity gas concentration in the standard gas required for calibration should also be in the above concentration range. In the case that the concentration of the impurity gas is extremely low, any weak adsorption will cause a large difference between the actual concentration of the impurity gas in the calibration gas and the label value (the concentration value marked by the standard gas manufacturer or the impurity gas concentration value in the prepared calibration gas), and further cause the calibration at the concentration to reduce the reliability of the calibration result of the chromatograph. Therefore, it is urgent to develop an enhanced insulating oil chromatographic detection method and device with automatic calibration function, so as to ensure that the actual concentration of the calibration gas is the same as the label value, improve the reliability of the calibration result, and make it suitable for the analysis of the impurity gases in the transformer oil with ultra-low concentration. SUMMARY

[0003] The technical problem to be solved by the application is how to solve the pipeline adsorption problem in the calibration process, improve the reliability of the calibration result, and further improve the accuracy of the analysis result.

[0004] The application solves the above technical problems by the following technical means:

[0005] The application discloses a plasma insulation oil chromatographic analysis device with automatic calibration function, which comprises a first gas cylinder filled with gas with a concentration higher than standard gas and a second gas cylinder filled with nitrogen, wherein the first gas cylinder is connected with a first pressure reducing valve, a first electromagnetic valve, a first sonic nozzle, a fifth electromagnetic valve, a first gas storage tank, a sixth electromagnetic valve, a second gas storage tank, an eighth electromagnetic valve, a first tenth communication valve, a first chromatographic column, a second chromatographic column, a third tenth communication valve and an EPD detector in sequence; the second gas cylinder is connected with a second pressure reducing valve, a second electromagnetic valve and a second sonic nozzle in sequence; the second sonic nozzle is connected to the upstream of the fifth electromagnetic valve; the upstream of the fifth electromagnetic valve is further connected through a fourth electromagnetic valve to the upstream of the first tenth communication valve; the first tenth communication valve is communicated with a second tenth communication valve, and the second communication valve is communicated with a third chromatographic column and a third communication valve in sequence; the second pressure reducing valve is further connected with a seventh electromagnetic valve and a ninth electromagnetic valve; the seventh electromagnetic valve is further connected to the second tenth communication valve; and the combined end of the first sonic nozzle and the second sonic nozzle is further connected to the upstream of the seventh electromagnetic valve through a third electromagnetic valve.

[0006] The application can automatically prepare calibration gas containing impurity gas with different concentrations by using bottle gas with a known concentration, diluting the bottle gas according to pressure through two buffer tanks.

[0007] Further, the first gas storage tank is provided with a first pressure sensor.

[0008] Further, the second gas storage tank is provided with a second pressure sensor.

[0009] Further, the first chromatographic column is an HD analysis column.

[0010] Further, the second chromatographic column is GDX502.

[0011] Further, the third chromatographic column is a TDX01 chromatographic column.

[0012] The application further provides an insulation oil chromatographic analysis method, which applies the device and comprises the following steps.

[0013] (1) pipeline adsorption process under high-concentration impurity gas

[0014] The first gas cylinder stores gas with higher impurity gas concentration than the calibration impurity gas concentration. First, high-purity nitrogen is used to purge the first and second tenth valves. Then, the gas in the first gas cylinder with higher impurity gas concentration than the calibration impurity gas concentration is used to make the flow pipeline rapidly adsorb a large amount of impurity gas, so that the adsorption amount reaches or exceeds the adsorption saturation amount under the calibration concentration. At the same time, the ultra-pure nitrogen gas also directly passes through the branch with the ninth electromagnetic valve to flush the EPD detector;

[0015] (2) Preparation of calibration concentration gas

[0016] It is known that the gas concentration in the first gas cylinder is ξ, and the calibration concentration is ψ. Since it contains seven impurity gases, the concentrations of each component are respectively:

[0017]

[0018]

[0019] A, B, C, D, E, F, and G correspond to seven gases, respectively.

[0020] By adding ultra-pure nitrogen for dilution, the concentration of each component decreases proportionally, and the dilution factor K = ξ / ψ.

[0021] It is known that the effective volume of the first gas storage tank is V1, and the effective volume of the second gas storage tank is V2, both in m 3 First, only the first electromagnetic valve and the fifth electromagnetic valve are opened, the first sonic nozzle flow is set to a set value, and the output is set for a certain period of time. At this time, the gas volume in the first gas storage tank is V1, and the second pressure sensor measures the pressure P a Then, the first electromagnetic valve and the first sonic nozzle are closed, and the electromagnetic valve is opened. The gas pressure P b after dilution by supplementing ultra-pure nitrogen is calculated:

[0022] According to Dalton's law of partial pressure, the partial pressure of impurity gas in the first gas storage tank before dilution is: ξP a , and after dilution, it is: ψP b . The amount of substance of impurity gas does not change before and after dilution, so:

[0023] ξP a V1=ψP b (V1+V2)

[0024] It is calculated that: P b =KP a V1 / (V1+V2)

[0025] At this time, the third electromagnetic valve and the sixth electromagnetic valve are opened, and the first electromagnetic valve is closed. Ultra-pure nitrogen enters the first and second gas storage tanks, and the first pressure sensor detects the pressure. When the pressure rises to P b- Set the third solenoid valve to close, the second solenoid valve to open, and the second sonic nozzle to start, and fill the gas to P b ; and wait to fill to P b It is indicated that the preparation of the gas of the required concentration for calibration is completed, and the solenoid valve and the sonic nozzle that are opened before are closed at this time;

[0026] (3) Saturated adsorption process of the pipeline at the calibration concentration

[0027] The seventh solenoid valve and the eighth solenoid valve are opened, the prepared gas of the calibration concentration is introduced into the tenth valve and the twentieth valve, and the quantitative ring structure and the flow path in the two ten valves are continuously flushed, and after 10 minutes of flushing, the gas path is completely saturated with the adsorption of the gas at the concentration, and the actual concentration will not be lower than the label value due to the impurity gas in the gas.

[0028] (4) Calibration gas analysis

[0029] The tenth valve and the twentieth valve are automatically switched, a certain amount of calibration gas is obtained by the quantitative ring, and the carrier gas (ultra-pure nitrogen) flowing out of the seventh solenoid valve is transported to the first chromatographic column, the second chromatographic column and the third chromatographic column, the separated gas is introduced into the thirtieth valve in time periods, and the gas is transmitted to the later EPD detector through valve switching, and the tail gas is discharged from the third exhaust port, after all the gas components are displayed, the system is corrected according to the peak display result, and the calibration process is completed.

[0030] Further, the step (1) is specifically: the first gas cylinder and the second gas cylinder are opened, the first pressure reducing valve and the second pressure reducing valve respectively reduce the pressure of the gas in the corresponding gas cylinder to a set value, the first solenoid valve, the fourth solenoid valve, the seventh solenoid valve and the ninth solenoid valve are opened, and the other solenoid valves are closed; the flow of the first sonic nozzle is set to a set value, the gas in the first gas cylinder enters the tenth valve and the twentieth valve through the first sonic nozzle, and the quantitative ring structure and the flow path in the two ten valves are flushed: first, the ultra-pure nitrogen in the second gas cylinder also enters the tenth valve and the twentieth valve, and is discharged from the exhaust holes of the tenth valve and the twentieth valve respectively, and the flowing gas pipeline is flushed; then, the bottle gas in the first gas cylinder with a higher impurity gas concentration than the calibration impurity gas concentration is used to make the flowing pipeline rapidly adsorb a large amount of impurity gas, so that the adsorption amount reaches or exceeds the adsorption saturation amount at the calibration concentration; at the same time, the ultra-pure nitrogen directly passes through the branch of the ninth solenoid valve to flush the EPD detector.

[0031] The advantages of the present application are:

[0032] The present application first uses high concentration gas to flush the pipeline, eliminates the interference of residual gas in the pipeline, and makes the flow pipeline quickly adsorb a large amount of impurity gas, so that the adsorption amount quickly reaches or exceeds the adsorption saturation amount under the calibration concentration, and then the calibration concentration gas is introduced for 10 minutes to make the pipeline adsorb saturated under the concentration, so as to ensure that the gas concentration value of the analysis is the label value, improve the reliability of the calibration result, and improve the analysis and detection accuracy.

[0033] The present application can automatically prepare calibration gas containing impurity gas with different concentrations by diluting the bottle gas with known concentration through two buffer tanks according to pressure. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the device in the embodiment of the present application. DETAILED DESCRIPTION

[0035] To make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme in the embodiment of the present application will be described clearly and completely below in combination with the embodiment of the present application. Obviously, the described embodiment is a part of the embodiments of the present application, not all the embodiments. Based on the embodiment in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the present application.

[0036] The present embodiment describes a plasma insulating oil chromatographic analysis device with automatic calibration function, which comprises a first gas cylinder 1 containing gas with a concentration higher than that of standard gas, a second gas cylinder 2 containing nitrogen, and the first gas cylinder 1 is connected in series with a first pressure reducing valve 3, a first electromagnetic valve 5, a first sonic nozzle 7, a fifth electromagnetic valve 11, a first gas storage tank 12, a sixth electromagnetic valve 13, a second gas storage tank 15, an eighth electromagnetic valve 17, a first tenth valve, a first chromatographic column 24, a second chromatographic column 25, a third tenth valve 28, and an EPD detector 29; the second gas cylinder 2 is connected in series with a second pressure reducing valve 4, a second electromagnetic valve 6, and a second sonic nozzle 8; the second sonic nozzle 8 is connected to the upstream of the fifth electromagnetic valve 11; a fourth electromagnetic valve is further connected between the upstream of the fifth electromagnetic valve 11 and the upstream of the first tenth valve 21; the first tenth valve 21 is in communication with a second tenth valve 22, the second communication valve is in communication with a third chromatographic column 26 and a third communication valve 28 in turn; a seventh electromagnetic valve 16 and a ninth electromagnetic valve 27 are further connected in series between the second pressure reducing valve 4 and the EPD detector 29; the seventh electromagnetic valve 16 is further connected to the second tenth valve 22; the merged end of the first sonic nozzle 7 and the second sonic nozzle 8 is further connected to the upstream of the seventh electromagnetic valve 16 through a third electromagnetic valve 9.

[0037] The first gas tank 12 is provided with a first pressure sensor 31. The second gas tank 15 is provided with a second pressure sensor 14. The first ten-way valve 21, the second ten-way valve 22 and the third ten-way valve 28 are respectively provided with a first emptying port 20, a second emptying port 23 and a third emptying port 30.

[0038] The use method of the above device is specifically as follows:

[0039] (1) High-concentration impurity gas pipeline adsorption process

[0040] The first cylinder 1 (containing a standard gas with a known concentration of seven kinds of gas impurities, and the carrier gas is nitrogen) and the second cylinder 2 (ultra-pure nitrogen, 99.999%) are opened. The first pressure reducing valve 3 and the second pressure reducing valve 4 respectively reduce the gas pressure in the corresponding cylinders to 0.6 MPa. The first electromagnetic valve 5, the fourth electromagnetic valve 10, the seventh electromagnetic valve 16 and the ninth electromagnetic valve 27 are opened, and the other electromagnetic valves are closed. The flow rate of the first sonic nozzle 7 is set to 20 ml / min (standard state). The gas in the first cylinder 1 enters the first ten-way valve 21 and the second ten-way valve 22 through the first sonic nozzle 7, and flushes the quantitative ring structure and the flow-through gas path in the two ten-way valves. The ultra-pure nitrogen in the second cylinder 2 also enters the first ten-way valve 21 and the second ten-way valve 22, and is first discharged from the first emptying port 20 and the second emptying port 23, respectively, to flush the flow-through gas pipeline. The flushing purpose is to eliminate the interference of residual gas in the pipeline, and to use the bottle gas in the first cylinder 1 with a higher concentration than the standard impurity gas to make the flow-through pipeline rapidly adsorb a large amount of impurity gas, so that the adsorption amount reaches or exceeds the adsorption saturation amount under the standard concentration. At the same time, the ultra-pure nitrogen will also directly pass through the branch pipe of the ninth electromagnetic valve 27 to flush the EPD detector 29. This process lasts for 2 minutes.

[0041] (2) Preparation of standard concentration gas

[0042] The concentration of the gas in the first cylinder 1 is known as ξ, and the standard concentration is ψ. Since it contains seven kinds of impurity gas, the concentration of each component is respectively:

[0043]

[0044]

[0045] A, B, C, D, E, F and G respectively correspond to CH4, C2H2, C2H4, C2H6, H2, CO and CO2.

[0046] By adding ultra-pure nitrogen for dilution, the concentration of each component decreases proportionally, and the dilution multiple K = ξ / ψ.

[0047] The effective volume of the first gas tank 12 is V1, and the effective volume of the second gas tank 15 is V2, both in m 3, first open only the first solenoid valve 5 and the fifth solenoid valve 11, the first sonic nozzle 7 flow is set to 20 ml / min (standard condition), the output time is 1 min; at this time the first gas tank 12 gas volume is V1, the second pressure sensor 31 measured pressure P a . Then, close the first solenoid valve 5 and the first sonic nozzle 7, open the solenoid valve 13, calculate the gas pressure P b after the dilution of the additional ultra-pure nitrogen:

[0048] According to Dalton's law of partial pressure, the partial pressure of impurity gas in the first gas tank 12 before dilution is: ξP a , after dilution: ψP b ; the amount of substance of impurity gas does not change before and after dilution, so:

[0049] ξP a V1=ψP b (V1+V2)

[0050] P b =KP a V1 / (V1+V2)

[0051] At this time, open the third solenoid valve 9 and the sixth solenoid valve 13, close the first solenoid valve 5, and the ultra-pure nitrogen enters the first gas tank 12 and the second gas tank 15, and the first pressure sensor 14 detects the pressure. When the pressure rises to P b -0.02 MPa, close the third solenoid valve 9, open the second solenoid valve 6, start the second sonic nozzle 8, and set the output flow to 50 ml / min. Fill at a slower speed to P b , to prevent overcharging due to too fast charging. When filled to P b , it indicates that the preparation of gas with the required concentration for calibration has been completed. At this time, close the previously opened solenoid valves and sonic nozzles, etc.

[0052] (3) Saturated process of pipeline adsorption at calibration concentration

[0053] Open the seventh solenoid valve 16 and the eighth solenoid valve 17, and prepare the calibration concentration gas into the first tenth valve 21 and the second tenth valve 22, continue to flush the quantitative ring structure and flow path in the two tenth valves, after 10 min of flushing, at this time the gas circuit has been completely saturated with the concentration of adsorption, and will not adsorb impurity gas in the gas to cause the actual concentration to be lower than the label value.

[0054] (4) Calibration gas analysis

[0055] The opening ten-way valve automatic valve cut, the quantitative ring obtains a certain amount of calibration gas, and the carrier gas (ultra-pure nitrogen) flowing out of the seventh electromagnetic valve 16 branch is transported to the first chromatographic column 24, the second chromatographic column 25, the third chromatographic column 26, wherein the first chromatographic column 24 is an HD analysis column, the second chromatographic column 25 is GDX502, and the third chromatographic column 26 is a TDX01 chromatographic column. The first chromatographic column 24 and the second chromatographic column 25 are used to separate CH4, C2H4, C2H6, C2H2, and the third chromatographic column 26 is used to separate H2, CO, CO2. The separated gas enters the thirtieth-way valve 28 in time periods, and the gas is transmitted to the later EPD detector 29 through the valve cut. The tail gas is discharged by the third exhaust port 30. After all the gas components are displayed, the system is corrected according to the peak display results, and the calibration process is completed.

[0056] After the calibration is completed, the electromagnetic valve 18 is opened, the sample gas to be measured enters the device from the sample gas inlet 19, so as to realize the analysis of each component impurity gas of the gas to be measured.

[0057] In this embodiment, high-concentration gas is used to flush the pipeline first, to exclude the interference of residual gas in the pipeline, and to make the flow pipeline quickly adsorb a large amount of impurity gas, so that the adsorption amount quickly reaches or exceeds the adsorption saturation amount under the calibration concentration. Then, the calibration concentration gas is introduced for 10 minutes to make the pipeline adsorb saturated under the concentration, so as to ensure that the analysis gas concentration value is the label value, improve the calibration result reliability, and improve the analysis and detection precision.

[0058] In this embodiment, the bottle gas with known concentration is diluted according to the pressure through two buffer tanks, to automatically prepare calibration gas containing impurity gas with different concentrations.

[0059] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features. The modification or replacement does not make the essence of the corresponding technical solution deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A plasma insulating oil chromatography analysis device with automatic calibration function, comprising a first gas cylinder (1) containing a gas concentration higher than that of a standard gas and a second gas cylinder (2) containing nitrogen, characterized in that, The first gas cylinder (1) is connected in series with the first pressure reducing valve (3), the first solenoid valve (5), the first sonic nozzle (7), the fifth solenoid valve (11), the first gas storage tank (12), the sixth solenoid valve (13), the second gas storage tank (15), the eighth solenoid valve (17), the first ten-way valve, the first chromatographic column (24), the second chromatographic column (25), the third ten-way valve (28), and the EPD detector (29); the second gas cylinder (2) is connected in series with the second pressure reducing valve (4), the second solenoid valve (6), and the second sonic nozzle (8); the second sonic nozzle (8) is connected in series upstream of the fifth solenoid valve (11); the upstream of the fifth solenoid valve (11) is connected to the upstream of the first ten-way valve (21). The first ten-way valve (21) is connected to the second ten-way valve (22), and the second ten-way valve (22) is connected to the third chromatographic column (26) and the third ten-way valve (28) in sequence; the second pressure reducing valve (4) and the EPD detector (29) are also connected in series with the seventh solenoid valve (16) and the ninth solenoid valve (27); the seventh solenoid valve (16) is also connected to the second ten-way valve (22); the combined end of the first sonic nozzle (7) and the second sonic nozzle (8) is also connected to the upstream of the seventh solenoid valve (16) through the third solenoid valve (9); the first chromatographic column (24) is an HD analytical column; the second chromatographic column (25) is a GDX502.

2. The plasma insulating oil chromatography analysis device with automatic calibration function according to claim 1, characterized in that, The first gas storage tank (12) is equipped with a first pressure sensor (31).

3. The plasma insulating oil chromatography analysis device with automatic calibration function according to claim 2, characterized in that, The second gas storage tank (15) is equipped with a second pressure sensor (14).

4. The plasma insulating oil chromatography analysis device with automatic calibration function according to claim 1 or 2, characterized in that, The third chromatographic column (26) is a TDX01 column.

5. A method for chromatographic analysis of insulating oil, applied to the apparatus of claim 3, characterized in that, Includes the following steps: (1) Pipeline adsorption process under high concentration of impurity gas The first gas cylinder (1) stores a gas with a concentration higher than the calibrated impurity gas concentration. First, high-purity nitrogen is used to purge the first ten-way valve (21) and the second ten-way valve (22). Then, the gas in the first gas cylinder (1) with a concentration higher than the calibrated impurity gas concentration is used to quickly adsorb a large amount of impurity gas into the flow pipeline, so that the adsorption amount reaches or exceeds the adsorption saturation amount at the calibrated concentration. At the same time, ultrapure nitrogen will also directly pass through the branch where the ninth solenoid valve (27) is located to flush the EPD detector (29). (2) Prepare gas of standard concentration Given that the gas concentration in the first gas cylinder (1) is ξ and the calibrated concentration is ψ, and since it contains seven impurity gases, the concentrations of each component are as follows: A, B, C, D, E, F, and G correspond to seven gases respectively; By adding ultrapure nitrogen gas for dilution, the concentration of each component decreases proportionally, and the dilution factor K = ξ / ψ. The effective volume of the first gas storage tank (12) is V1, and the effective volume of the second gas storage tank (15) is V2, both in m³. 3 First, only the first solenoid valve (5) and the fifth solenoid valve (11) are opened, the flow rate of the first sonic nozzle (7) is set to the set value, and the output duration is set. At this time, the gas volume in the first gas storage tank (12) is V1, and the pressure measured by the second pressure sensor (31) is P. a Then, close the first solenoid valve (5) and the first sonic nozzle (7), open the sixth solenoid valve (13), and calculate the gas pressure P after dilution with replenished ultrapure nitrogen. b : According to Dalton's law of partial pressures, the partial pressure of the impurity gas in the first gas storage tank (12) before dilution is: ξP a After dilution, it becomes: ψP b ;dilution The amount of impurity gaseous substances did not change before and after, therefore: ξP a V1=ψP b (V1+V2) Calculation yields: P b =KP a V1 / (V1+V2) At this time, the third solenoid valve (9) and the sixth solenoid valve (13) are opened, and the first solenoid valve (5) is closed. Ultrapure nitrogen enters the first gas storage tank (12) and the second gas storage tank (15). The first pressure sensor (14) detects the pressure. When the pressure rises to P b - When the set value is reached, the third solenoid valve (9) is closed, the second solenoid valve (6) is opened, and the second sonic nozzle (8) is activated to inflate to P at a slower speed. b ;Please charge to P b This indicates that the gas preparation for the required concentration has been completed. At this point, close the previously opened solenoid valve and sonic nozzle. (3) Pipeline adsorption saturation process at calibrated concentration Open the seventh solenoid valve (16) and the eighth solenoid valve (17), and put the prepared calibrated concentration gas into the first ten-way valve (21) and the second ten-way valve (22). Continue to flush the quantitative ring structure and flow path in the two ten-way valves. After flushing for 10 minutes, the gas path is completely saturated with adsorption at this concentration and will no longer adsorb impurities in the gas, causing the actual concentration to be lower than the label value. (4) Calibration gas analysis The first ten-way valve (21) and the second ten-way valve (22) are automatically shut off. A certain amount of calibration gas is quantitatively obtained by the quantitative loop and transported by the carrier gas flowing out of the branch where the seventh solenoid valve (16) is located to the first chromatographic column (24), the second chromatographic column (25) and the third chromatographic column (26). The separated gas enters the third ten-way valve (28) in time intervals and is transferred to the downstream EPD detector (29) by valve shut-off. The tail gas is discharged from the third vent (30). After all gas components have peaked and displayed, the system is corrected according to the peak results, and the calibration process ends.

6. The method for chromatographic analysis of insulating oil according to claim 5, characterized in that, The specific steps (1) are as follows: open the first gas cylinder (1) and the second gas cylinder (2), the first pressure reducing valve (3) and the second pressure reducing valve (4) reduce the gas pressure in the corresponding gas cylinder to the set value respectively, open the first solenoid valve (5), the fourth solenoid valve (10), the seventh solenoid valve (16) and the ninth solenoid valve (27), and close the other solenoid valves; set the flow rate of the first sonic nozzle (7) to the set value, and the gas in the first gas cylinder (1) enters the first ten-way valve (21) and the second ten-way valve (22) through the first sonic nozzle (7) to start flushing the metering loop in the two ten-way valves. Structure and flow path: First, the ultrapure nitrogen in the second gas cylinder (2) also enters the first ten-way valve (21) and the second ten-way valve (22), and then is discharged from the vent holes of the first ten-way valve (21) and the second ten-way valve (22) respectively to flush the flow path; then, the gas in the first gas cylinder (1) with a higher concentration than the calibrated impurity gas is used to make the flow path quickly adsorb a large amount of impurity gas, so that the adsorption amount reaches or exceeds the adsorption saturation amount under the calibrated concentration; at the same time, the ultrapure nitrogen will also directly pass through the branch where the ninth solenoid valve (27) is located to flush the EPD detector (29).

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