Chromatographic technology-based PANs analysis device and method

Abstract

The invention relates to a chromatographic technology, and particularly provides a PANs analysis device and method based on the chromatographic technology, the analysis device comprises a detector, a chromatographic column and a first quantitative loop, and the detector, the chromatographic column and the first quantitative loop are all connected with a port of a multi-ported valve; one end of the first pipeline is selectively connected with air and standard gas, the other end of the first pipeline is connected with a first port of the multi-way valve, one end of the second pipeline is connected with the chromatographic column, and the other end of the second pipeline is connected with a second port of the multi-way valve; the second quantitative ring is arranged on the first pipeline; under the switching of the flow path switching unit, the second port is communicated with the chromatographic column through a second pipeline or is communicated with the chromatographic column through the second pipeline, the second quantitative ring and the second pipeline in sequence, and the first port is connected with air or standard gas through a first pipeline. The method has the advantages of accurate measurement and the like, and is applied to air detection.

Description

TECHNICAL FIELD

[0001] The present application relates to chromatography technology, in particular to a PANs analysis device and method based on chromatography technology. BACKGROUND

[0002] Peroxyacetyl nitrate (PAN) is the most important photochemical secondary pollutant besides ozone, which is not directly discharged by natural sources and human sources, but only comes from photochemical reaction, and is an important indicator of atmospheric photochemical pollution. At present, long-term online continuous monitoring of such pollutants has been carried out in various monitoring stations in China.

[0003] At present, the mainstream PANs analysis method is a detection method combining gas chromatography and ECD detector. The internal standard method is often used in quantitative gas chromatography, and a PANs calibrator is equipped to calibrate the PANs analyzer, and the calibration period is generally one week or two weeks. The disadvantages of this method are: 1. The online monitoring instrument of gas chromatography generally has the problem of long test period. Only one group of data can be measured in a test period. A test period includes several steps such as pre-pumping, sampling, sampling, back blowing, etc., each step is carried out separately, so that the analysis period of the test is longer.

[0004] Calibration and measurement are carried out separately. The instrument needs to change the sample gas measurement mode to calibration state during calibration. The PAN standard gas has a certain stabilization time from synthesis to reaching the target concentration. Therefore, the PAN analyzer in the prior art will lose a long time of measurement data during each calibration.

[0005] 2. The internal standard method has problems such as poor mixing of internal standard in sample, reaction between internal standard and sample components, variable purity of internal standard, etc. SUMMARY

[0006] In order to solve the above problems in the prior art, the present application provides a PANs analysis device based on chromatography technology.

[0007] The purpose of the present application is achieved by the following technical solutions: The PANS analysis device based on chromatography technology comprises a detector, a chromatographic column and a first quantitative ring, and the detector, the chromatographic column and the first quantitative ring are connected to the ports of a multi-way valve; the analysis device further comprises: A first pipeline and a second pipeline, one end of the first pipeline is selectively connected to air and standard gas, the other end is connected to the first port of the multi-way valve, one end of the second pipeline is connected to the chromatographic column, the other end is connected to the second port of the multi-way valve; A second quantitative ring, the second quantitative ring is arranged on the first pipeline; The flow path switching unit is switched, and the second port is communicated with the chromatographic column through the second pipe, or is communicated with the chromatographic column through the second pipe, the second quantitative ring and the second pipe in sequence, and the first port is connected with air or standard gas through the first pipe; When the multi-way valve is switched to the first state, air or standard gas passes through the first pipe, the second quantitative ring and the multi-way valve in sequence, when switched to the second state, carrier gas passes through the multi-way valve, the first quantitative ring, the second port, the second pipe, the chromatographic column and the detector in sequence, and when switched to the third state, carrier gas passes through the multi-way valve, the first quantitative ring, the second port, the second pipe, the second quantitative ring, the second pipe, the chromatographic column and the detector in sequence.

[0008] The application also aims to provide a PANs analysis method based on chromatographic technology, and the application aims to achieve the application by the following technical scheme: The PANs analysis method based on chromatographic technology comprises the following stages in each detection cycle: The sample gas collection stage, the multi-way valve is switched to the first state, the flow path switching unit is switched, and the sample gas passes through the first pipe, the first port of the multi-way valve, the first quantitative ring and the multi-way valve in sequence; The sample gas injection stage, the multi-way valve is switched to the second state, the flow path switching unit is switched, and carrier gas passes through the multi-way valve, the first quantitative ring, the second port of the multi-way valve, the second pipe, the multi-way valve, the chromatographic column and the detector in sequence; Meanwhile, standard gas passes through the first pipe, the second quantitative ring and the first port in sequence; The standard gas analysis stage, the multi-way valve is switched to the third state, the flow path switching unit is switched, and carrier gas passes through the multi-way valve, the first quantitative ring, the second port, the second pipe, the second quantitative ring, the second pipe, the multi-way valve, the chromatographic column and the detector in sequence.

[0009] Compared with the prior art, the application has the beneficial effects that: 1. The detection cycle is short; In each detection cycle, sample gas injection and standard gas sampling are performed at the same time, and the entire detection cycle is shortened; 2. The accuracy is good; The new concentration calculation method is used, and the detection accuracy is improved; The linkage of the EPC and the sensor is used, so that the sample gas or standard gas entering the chromatographic column has the same pressure, and the detection accuracy is improved. BRIEF DESCRIPTION OF DRAWINGS

[0010] The disclosure of the application will become more apparent with reference to the drawings. It is easy for those skilled in the art to understand that the drawings are only used to illustrate the technical scheme of the application, and are not intended to limit the protection scope of the application. In the drawings: Figure 1 is a structural schematic diagram of an analysis device according to an embodiment of the present application in a first state; Figure 2 is a structural schematic diagram of an analysis device according to an embodiment of the present application in a second state; Figure 3 is a structural schematic diagram of an analysis device according to an embodiment of the present application in a third state. DETAILED DESCRIPTION

[0011] Figures 1-3 The following description describes optional embodiments of the present application to teach those skilled in the art how to implement and reproduce the present application. Some conventional aspects have been simplified or omitted for the sake of explanation. Those skilled in the art should understand that variations or substitutions from these embodiments will be within the scope of the present application. Those skilled in the art should understand that the following features can be combined in various ways to form multiple variations of the present application. Thus, the present application is not limited to the following optional embodiments, but is only limited by the claims and their equivalents.

[0012] Example 1.

[0013] The PANs analysis device based on chromatographic technique according to an embodiment of the present application, as shown in Figure 1 includes: a detector 51, a chromatographic column 42 and a first quantitative ring 31, all of which are connected to a port of a multi-way valve 11, which are all prior art in the field.

[0014] One end of a first pipe 21 is selectively connected to air and a standard gas, and the other end is connected to a first port of the multi-way valve 11, one end of a second pipe 22 is connected to the chromatographic column 42, and the other end is connected to a second port of the multi-way valve 11.

[0015] A second quantitative ring 32 is arranged on the first pipe 21.

[0016] Under the switching of the flow path switching unit, the second port is connected to the chromatographic column 42 through the second pipe 22, or is connected to the chromatographic column 42 through the second pipe 22, the second quantitative ring 32 and the second pipe 22 in sequence, and the first port is connected to air or a standard gas through the first pipe 21.

[0017] When the multi-way valve 11 is switched to the first state, air or standard gas passes through the first pipe 21, the second metering ring 32 and the multi-way valve 11 in turn, when switched to the second state, carrier gas passes through the multi-way valve 11, the first metering ring 31, the second port, the second pipe 22, the chromatographic column 42 and the detector 51 in turn, when switched to the third state, carrier gas passes through the multi-way valve 11, the first metering ring 31, the second port, the second pipe 22, the second metering ring 32, the second pipe 22, the chromatographic column 42 and the detector 51 in turn.

[0018] To realize the flow path switching, further, the flow path switching unit comprises: The first switching module is configured to selectively connect the second port to the second pipe 22 or the first pipe 21.

[0019] The second switching module is configured to selectively connect one end of the second metering ring 32 to the first pipe 21 or the first switching module.

[0020] The third switching module is configured to selectively connect the other end of the second metering ring 32 to the first pipe 21 or the second pipe 22.

[0021] To improve the detection accuracy, further, the analysis device further comprises: The sensor 81 is configured to obtain the pressure in the second pipe 22 upstream of the chromatographic column 42.

[0022] The carrier gas enters the multi-way valve 11 through the EPC 71.

[0023] The controller is configured to adjust the EPC 71 so that the output value of the sensor 81 is constant.

[0024] To improve the detection accuracy, further, the analysis unit processes the output signal of the detector 51 to obtain the concentration C of PANs in the sample gas sample : C sample =(K1×A sample / A std )×K2×C std +b, K1=A 2average / A 1average ; K2=A std current / A std ref ; b=(1 / n)×Σ[C std cert -(A std i / A std ref )×C std cert ]; A sample is the peak area of PANs in the sample gas, A std is the peak area of PANs in the standard gas, and Cstd is the concentration of the standard gas, A 2average is the average of the peak areas of the standard gas in M consecutive tests of the second quantitative ring 32, A 1average is the average of the peak areas of the standard gas in M consecutive tests of the first quantitative ring 31, A std current is the peak area of the standard gas in the current cycle, A std ref is the peak area of the standard gas in the current cycle, A std cert is the concentration of the standard gas, A std i is the peak area of the standard gas in the i-th calibration.

[0025] The PANs analysis method based on chromatography technology in the embodiment of the application comprises the following stages in each detection cycle: The sample gas collection stage, as shown in FIG. 4, the multi-way valve 11 is switched to the first state, the flow path switching unit is switched, and the sample gas sequentially passes through the first pipeline 21, the first port of the multi-way valve 11, the first quantitative ring 31 and the multi-way valve 11. Figure 1

[0026] The sample gas injection stage, as shown in FIG. 5, the multi-way valve 11 is switched to the second state, the flow path switching unit is switched, and the carrier gas sequentially passes through the multi-way valve 11, the first quantitative ring 31, the second port of the multi-way valve 11, the second pipeline 22, the multi-way valve 11, the chromatographic column 42 and the detector 51. Figure 2

[0027] At the same time, the standard gas sequentially passes through the first pipeline 21, the second quantitative ring 32 and the first port.

[0028] The standard gas analysis stage, as shown in FIG. 6, the multi-way valve 11 is switched to the third state, the flow path switching unit is switched, and the carrier gas sequentially passes through the multi-way valve 11, the first quantitative ring 31, the second port, the second pipeline 22, the second quantitative ring 32, the second pipeline 22, the multi-way valve 11, the chromatographic column 42 and the detector 51. Figure 3 The purge stage, as shown in FIG. 7, the multi-way valve 11 is switched to the first state, the flow path switching unit is switched, and the gas sequentially passes through the first pipeline 21, the first port of the multi-way valve 11, the first quantitative ring 31 and the multi-way valve 11.

[0029] Figure 1 In the accompanying drawings, the blue color represents the flow direction, and the red color represents the flow path disconnection.

[0030] In order to improve the detection accuracy, further, in the sample gas injection stage and the standard gas analysis stage, the EPC 71 of the carrier gas flow path is adjusted, so that the gas pressure in the second pipeline 22 upstream of the chromatographic column 42 is equal. Figures 1-3

[0031] ​​​​​

[0032] To improve detection accuracy, the analysis unit further processes the output signal of the detector 51 to obtain the PANs concentration C in the sample gas. sample : C sample =(K1×A sample / A std )×K2×C std +b, K1=A 2average / A 1average ; K2=A std current / A std ref ; b=(1 / n)×Σ[C std cert -(A std i / A std ref )×C std cert ]; A sample It is the peak area of ​​the sample gas PANs, A std It is the peak area of ​​standard gas PANs, C std It is the concentration of PANs standard gas, A 2average It is the average peak area of ​​the standard gas from M consecutive tests in the second quantitative loop, A. 1average It is the average peak area of ​​the standard gas from M consecutive tests in the first quantitative loop 31, where M is an integer greater than 2, and A std current It is the measured peak area of ​​the standard gas in the current cycle, A std ref Where n is the peak area of ​​the reference standard gas, n is the number of test standard gas data points, Σ is the sum of i from 1 to n, and C is the peak area of ​​the reference standard gas. std cert It is the concentration of the standard gas being tested, A std i It is the peak area of ​​the standard gas measured in the i-th calibration.

[0033] During the sample gas collection and purging stages, the gas passes sequentially through the first pipe 21, the second metering ring 32, the first port of the multi-way valve, the first metering ring 31, and the multi-way valve 11.

[0034] Example 2.

[0035] Application examples of the PANs analysis apparatus and method based on chromatography technology according to Embodiment 1 of the present invention.

[0036] In this application example, such as Figure 1 As shown, the carrier gas is connected to the port of the multi-way valve 11 via EPC71. The two ends of the first quantitative loop 31, one end of the chromatographic column 42, and one end of the pre-column 41 are respectively connected to the port of the multi-way valve 11. The other end of the chromatographic column 42 is connected to the detector 51, and the other end of the pre-column 41 is connected in sequence to the pressure sensor 81, the second pipeline 22, and the second port of the multi-way valve 11.

[0037] The air and the standard gas are connected to the first pipe 21, the second quantitative ring 32 and the first port of the multi-way valve 11 in sequence through the two-position three-way electromagnetic valve 61.

[0038] The flow path switching unit includes a plurality of two-position three-way electromagnetic valves, which are respectively arranged on the first pipe 21 and the second pipe 22, so that when switched, the second port is communicated with the pre-column 41 through the second pipe 22, or is communicated with the pre-column 41 through the second pipe 22, the second quantitative ring 32 and the second pipe 22 in sequence, and the first port is connected to the air or the standard gas through the first pipe 21 and the second quantitative ring 32.

[0039] The analysis unit is used to obtain the concentration C of PANs in the air according to the output signal of the detector 51. sample : C sample =(K1×A sample / A std )×K2×C std +b, K1=A 2average / A 1average ; K2=A std current / A std ref ; b=(1 / n)×Σ[C std cert -(A std i / A std ref )×C std cert ]; A sample is the peak area of the sample gas PANs, A std is the peak area of the standard gas PANs, C std is the concentration of the PANs standard gas, A 2average is the average value of the peak area of the standard gas tested by the second quantitative ring 32 for three times in succession, A 1average is the average value of the peak area of the standard gas tested by the first quantitative ring 31 for three times in succession, A std current is the peak area of the standard gas actually measured in the current period, A std ref is the peak area of the standard gas in the base, n is the number of data points of the standard gas tested, Σ is the summation of i from 1 to n, C std cert is the concentration of the standard gas tested, A std i is the peak area of the standard gas measured in the i-th calibration.

[0040] The PANs analysis method based on the chromatographic technology in the embodiment of the application, i.e., the working method of the analysis device in the embodiment, includes the following stages in each detection period: The sample gas collection stage, such as Figure 1As shown, when the multi-way valve 11 is switched to the first state, the flow path switching unit is switched, and the sample gas passes sequentially through the two-position three-way solenoid valve 61, the first pipeline 21, the second metering ring 32 (passing in the forward direction), the first port of the multi-way valve 11, the first metering ring 31 and the multi-way valve 11, and then is vented.

[0041] During the sample gas injection stage, such as Figure 2 As shown, when the multi-way valve 11 switches to the second state, the flow path switching unit switches, and the carrier gas passes sequentially through EPC71, multi-way valve 11, first quantitative loop 31 (passing in reverse), second port of multi-way valve 11, second pipeline 22, pre-column 41, multi-way valve 11, chromatographic column 42 and detector 51.

[0042] Meanwhile, the standard gas passes sequentially through the two-position three-way solenoid valve 61, the first pipeline 21, the second metering ring 32, and the first port, and then is vented.

[0043] Standard gas analysis stage, such as Figure 3 As shown, when the multi-way valve 11 switches to the third state, the flow path switching unit switches, and the carrier gas passes sequentially through EPC71, multi-way valve 11, first quantitative loop 31, second port, second pipeline 22, second quantitative loop 32, second pipeline 22, pre-column 41, multi-way valve 11, chromatographic column 42 and detector 51.

[0044] During the sample gas injection stage and the standard gas analysis stage, the EPC71 of the carrier gas flow path is adjusted to make the gas pressure in the second pipe 22 upstream of the chromatographic column 42 equal.

[0045] During the purging phase, such as Figure 1 As shown, when the multi-way valve 11 switches to the first state, the flow path switching unit switches, and the gas (air) passes sequentially through the two-position three-way solenoid valve 61, the first pipeline 21, the second metering ring 32, the first port, the first metering ring 31, and the multi-way valve 11.

[0046] The analysis unit processes the output signal of the detector 51 to obtain the PANs concentration C in the sample gas. sample : C sample =(K1×A sample / A std )×K2×C std +b, K1=A 2average / A 1average ; K2=A std current / A std ref ; b=(1 / n)×Σ[C std cert -(A std i / A std ref )×C std cert ]; A sample is the peak area of the sample gas PANs, A std is the peak area of the standard gas PANs, C std is the standard gas PANs concentration, A 2average is the average of the standard gas peak area tested 3 times consecutively by the second quantification ring 32, A 1average is the average of the standard gas peak area tested 3 times consecutively by the first quantification ring 31, A std current is the current cycle measured standard gas peak area, A std ref is the reference standard gas peak area, n is the number of test standard gas data points, and Σ is the summation of i from 1 to n, C std cert is the test standard gas concentration, A std i is the measured standard gas peak area in the i-th calibration.

[0047] The measured parameters of this example are as follows: The 4ppb PAN standard gas was synthesized on-line, passed through the first quantification ring 31 and the second quantification ring 32 in turn, and 3 sets of stable peak areas were recorded consecutively, as shown in Table 1.

[0048] Table 1 is 3 sets of stable peak areas and K1.

[0049] .

[0050] When the normal continuous internal standard test, A std ref is the average of the peak area tested by the second quantification ring 32 in the previous ten times.

[0051] Ten sets of peak areas of 4ppb PAN standard gas tested by the second quantification ring 32 were recorded consecutively, and A std ref， is calculated as shown in Table 2.

[0052] Table 2 is the peak area and A std ref .

[0053] .

[0054] Two consecutive sample internal standard tests were recorded, as shown in Table 3.

[0055] Table 3 is the A sample , A std of the sample gas and the standard gas.

[0056] .

[0057] Sample 1 concentration calculation: b=(1 / n) ·Σ[C std -(A stdi / A stdref )·C std= (1 / 1) ·Σ[4-(2324.83 / 2319.02)·4]=-0.01ppb.

[0058] K2= A std current / A std ref =2324.83 / 2319.02=1.0025.

[0059] C sample =(K1·A sample / A std )·K2·C std +b.

[0060] =(0.9133·1214.39 / 2324.83) ·1.0025·4-0.01.

[0061] =1.903ppb.

[0062] Sample gas 2 concentration calculation: At this time, the first group of peak areas involved in the calculation in the A std ref parameter are iterated by the internal standard peak area in sample gas measurement 1, and the A std ref value is corrected to 2319.94.

[0063] b=(1 / n)·Σ[C std -( A stdi / A stdref )·C std ].

[0064] = (1 / 2)·[[4-(2324.83 / 2319.94)·4]+[4-(2317.66 / 2319.94)·4]].

[0065] b= -0.0023 ppb.

[0066] At this time, the first group of peak areas involved in the calculation in the A std ref1 parameter are iterated by the internal standard peak area in sample gas measurement 1, and the A std ref1 value is corrected to 2319.94.

[0067] K2= A std current / A std ref1 =2317.66 / 2319.94=0.999.

[0068] C sample =(K1·A sample / A std ) ·K2·C std +b.

[0069] = (0.9133 · 1246.84 / 2317.66) · 0.999 · 4 - 0.0023.

[0070] = 1.9611 ppb.

Claims

1. A PANs analysis device based on chromatographic technique comprising a detector, a chromatographic column and a first quantification loop, all of which are connected to ports of a multi-way valve; characterized in that, The analysis device further comprises: a first pipe and a second pipe, one end of the first pipe selectively connects air and a standard gas, the other end connects a first port of the multi-way valve, one end of the second pipe connects the chromatographic column, the other end connects a second port of the multi-way valve; a second quantitative ring, which is arranged on the first pipe; a flow path switching unit, under the switching of the flow path switching unit, the second port is communicated with the chromatographic column through the second pipe, or is sequentially communicated with the chromatographic column through the second pipe, the second quantitative ring and the second pipe, and the first port is connected with the air or the standard gas through the first pipe; when the multi-way valve is switched to the first state, the air or the standard gas sequentially passes through the first pipe, the second quantitative ring and the multi-way valve, when switched to the second state, the carrier gas sequentially passes through the multi-way valve, the first quantitative ring, the second port, the second pipe, the chromatographic column and the detector, and when switched to the third state, the carrier gas sequentially passes through the multi-way valve, the first quantitative ring, the second port, the second pipe, the second quantitative ring, the second pipe, the chromatographic column and the detector.

2. The analysis device of claim 1, wherein, The flow path switching unit comprises: a first switching module, which is used for selectively communicating the second port with the second pipe or the first pipe; a second switching module, which is used for selectively communicating one end of the second quantitative ring with the first pipe or the first switching module; a third switching module, which is used for selectively communicating the other end of the second quantitative ring with the first pipe or the second pipe.

3. The analysis device of claim 1, wherein, The analysis device further comprises: a sensor, which is used for obtaining the pressure in the second pipe upstream of the chromatographic column; an EPC, through which the carrier gas enters the multi-way valve; a controller, which is used for adjusting the EPC so that the output value of the sensor is unchanged.

4. The analysis device according to claim 1 or 3, characterized in that The analysis device further comprises a pre-column, in the second state and the third state, the second pipe sequentially communicates with the pre-column, the multi-way valve, the chromatographic column and the detector.

5. The analysis device of claim 1, wherein, The analysis unit processes the output signal of the detector to obtain the concentration C of PANs in the sample gas sample : C sample = (K1 x A sample / A std ) x K2 x C std + b, K1 = A 2average / A 1average ; K2 = A std current / A std ref ; b = (1 / n) x Σ[C std cert - (A std i / A std ref ) x C std cert ]; A sample is the peak area of the sample gas PANs, A std is the peak area of the calibration gas PANs, C std is the calibration gas PANs concentration, A 2average is the average of the calibration gas peak areas from M consecutive tests of the second quantification loop, A 1average is the average of the calibration gas peak areas from M consecutive tests of the first quantification loop, M is an integer greater than 2, A std current is the current cycle measured calibration gas peak area, A std ref is the reference calibration gas peak area, n is the number of test calibration gas data points, Σ is the summation from i = 1 to n, C std cert is the test calibration gas concentration, A std i is the measured calibration gas peak area from the i-th calibration.

6. The method for PANs analysis based on chromatographic techniques, characterized in that, In each detection cycle, the analysis method comprises the following stages: a sample gas collection stage, the multi-way valve is switched to the first state, the flow path switching unit is switched, and the sample gas sequentially passes through the first pipe, the first port of the multi-way valve, the first quantitative ring and the multi-way valve; a sample gas injection stage, the multi-way valve is switched to the second state, the flow path switching unit is switched, and the carrier gas sequentially passes through the multi-way valve, the first quantitative ring, the second port of the multi-way valve, the second pipe, the chromatographic column and the detector; at the same time, the standard gas sequentially passes through the first pipe, the second quantitative ring and the first port; a standard gas analysis stage, the multi-way valve is switched to the third state, the flow path switching unit is switched, and the carrier gas sequentially passes through the multi-way valve, the first quantitative ring, the second port, the second pipe, the second quantitative ring, the second pipe, the multi-way valve, the chromatographic column and the detector.

7. The analysis method according to claim 6, characterized in that, The analysis method comprises the following stages: a purge stage, the multi-way valve is switched to the first state, the flow path switching unit is switched, and the cleaning gas sequentially passes through the first pipe, the first port of the multi-way valve, the first quantitative ring and the multi-way valve.

8. The analysis method according to claim 6, characterized in that, In the sample gas injection stage and the standard gas analysis stage, the EPC of the carrier gas flow path is adjusted so that the gas pressure in the second pipe upstream of the chromatographic column is equal.

9. The analysis method according to claim 6, characterized in that, The analysis unit processes the output signal of the detector to obtain the concentration C of PANs in the sample gas sample : C sample = (K1 x A sample / A std ) x K2 x C std + b, K1 = A 2average / A 1average ; K2 = A std current / A std ref ; b = (1 / n) x Σ[C std cert - (A std i / A std ref ) x C std cert ]; A sample is the peak area of the sample gas PANs, A std is the peak area of the calibration gas PANs, C std is the concentration of the PANs in the calibration gas, A 2average is the average of the peak areas of the calibration gas for M consecutive tests of the second quantification loop, A 1average is the average of the peak areas of the calibration gas for M consecutive tests of the first quantification loop, M is an integer greater than 2, A std current is the peak area of the calibration gas measured in the current cycle, A std ref is the peak area of the calibration gas, n is the number of data points of the calibration gas, Σ is the summation of i from 1 to n, C std cert is the concentration of the calibration gas, A std i is the peak area of the calibration gas measured in the i-th calibration.

10. The analysis method of claim 7, wherein, In the sample gas collecting stage and the purging stage, the gas passes through the first pipeline, the second metering ring, the first port of the multi-way valve, the first metering ring and the multi-way valve in sequence. In the sample gas collecting stage and the purging stage, the gas passes through the first pipeline, the second metering ring, the first port of the multi-way valve, the first metering ring and the

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