CN116008487A - Multi-concentration greenhouse gas calibration device with vacuum purging function - Google Patents
Multi-concentration greenhouse gas calibration device with vacuum purging function Download PDFInfo
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- CN116008487A CN116008487A CN202310300745.9A CN202310300745A CN116008487A CN 116008487 A CN116008487 A CN 116008487A CN 202310300745 A CN202310300745 A CN 202310300745A CN 116008487 A CN116008487 A CN 116008487A
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- 239000005431 greenhouse gas Substances 0.000 title claims abstract description 72
- 238000010926 purge Methods 0.000 title claims abstract description 39
- 239000007789 gas Substances 0.000 claims abstract description 91
- 238000000034 method Methods 0.000 claims abstract description 13
- 238000007664 blowing Methods 0.000 abstract description 7
- 238000001514 detection method Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 5
- 230000005540 biological transmission Effects 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000012544 monitoring process Methods 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 238000005259 measurement Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000003344 environmental pollutant Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 231100000719 pollutant Toxicity 0.000 description 2
- 238000009423 ventilation Methods 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
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Abstract
The utility model provides a multi-concentration greenhouse gas calibration device with vacuum purging function, relates to gas detection technical field, has solved current purging inefficiency, calibration time length, purge the poor problem of effect, and the device includes gas output device and pressure interface, gas output device connects output interface, gas output device is used for outputting the greenhouse gas of different concentration; the pressure interface is communicated with one end of the two-position two-way valve and the first vacuum pump, a pressure gauge is arranged between the two-position two-way valve and the pressure interface, the other end of the two-position two-way valve is connected with the pressure control valve, and the pressure control valve is connected with the second vacuum pump. According to the vacuum blowing device and the vacuum blowing method, vacuum blowing is adopted for blowing equipment to be calibrated, so that the blowing efficiency and effect of the cavity of the equipment to be calibrated are improved, and the calibration time is shortened.
Description
Technical Field
The invention relates to the technical field of gas detection, in particular to a multi-concentration greenhouse gas calibration device with a vacuum purging function.
Background
With the development of the industrial age, a series of problems such as atmospheric pollution, pollution control and the like are accompanied with the development of the industrial age. The monitoring of the atmospheric pollutants is an important step for pollution control, and the existing gas pollution monitoring method advances towards the on-line measurement and real-time measurement directions. Methane gas is an important monitoring component for monitoring pollutants, wherein the high-precision greenhouse gas detection equipment must be subjected to the step of calibrating an instrument before the equipment is put into use, and the calibration of the instrument refers to the determination of the function relationship between the output signal value of the instrument and the gas concentration of detected greenhouse gas, which is necessary for the instrument to be capable of outputting high-precision and high-precision detection results. The existing greenhouse gas calibration method mostly adopts a gas distribution instrument to configure greenhouse gas with known concentration or directly adopts the greenhouse gas with known concentration to be filled into a gas detection instrument, and the relation between the concentration of the monitored greenhouse gas and the output signal of the instrument is established by analyzing the signal of the instrument, so that the calibration of the instrument is completed.
The main defects of the existing greenhouse gas scaling device are as follows:
because the purging needs to be carried out in the air chamber after the single greenhouse gas concentration is calibrated each time, the next concentration gas can be calibrated after the air in the air chamber is completely purged; the existing calibration device has low purging efficiency, and thus the calibration time is long.
Disclosure of Invention
The invention provides a multi-concentration greenhouse gas calibration device with a vacuum purging function, which aims to solve the problems of low purging efficiency, poor purging effect and long calibration time of the existing greenhouse gas calibration device.
The technical scheme adopted by the invention for solving the technical problems is as follows:
the multi-concentration greenhouse gas scaling device with the vacuum purging function comprises a gas output device and a pressure interface, wherein the gas output device is connected with the output interface and is used for outputting greenhouse gases with different concentrations; the pressure interface is communicated with one end of the two-position two-way valve and the first vacuum pump, a pressure gauge is arranged between the two-position two-way valve and the pressure interface, the other end of the two-position two-way valve is connected with the pressure control valve, and the pressure control valve is connected with the second vacuum pump.
In a preferred embodiment, the gas output device is capable of outputting a continuous concentration of greenhouse gas.
In a preferred embodiment, the gas output means comprises N 2 Gas output mechanism, air output mechanism and greenhouse gas output machineConstruct, said N 2 The gas output mechanism, the air output mechanism and the greenhouse gas output mechanism can all output gas to the equipment to be calibrated through the output interfaces.
In a preferred embodiment, the N 2 The gas output mechanism comprises N connected in sequence 2 The greenhouse gas output mechanism comprises a greenhouse gas cylinder, a third two-position two-way valve, a third adjustable throttle valve and a third mass flowmeter which are sequentially connected; the first mass flowmeter, the second mass flowmeter and the third mass flowmeter are all connected with the output interface.
In a preferred embodiment, the pressure gauge is located between the first vacuum pump and the pressure port.
In a preferred embodiment, the method for vacuum purging the equipment to be calibrated by the multi-concentration greenhouse gas calibration device comprises the following steps of:
closing the output interface, opening the pressure interface, enabling the two-position two-way valve to be in a closed state, opening the first vacuum pump, closing the first vacuum pump when the air pressure in the equipment to be calibrated is not higher than 10Pa, and ventilating the equipment to be calibrated and the outside, or opening the output interface to enable the air in the air output device to be ventilated into the equipment to be calibrated, so that the equipment to be calibrated is restored to a normal atmospheric pressure state.
In a preferred embodiment, the scaling device can control the air pressure in the equipment to be scaled, and the method for controlling the air pressure in the equipment to be scaled by the scaling device is as follows: when the gas output device operates, the two-position two-way valve is opened to an opening state, the second vacuum pump is started, and the air pressure of the equipment to be calibrated is controlled to be a specified value through the cooperation of the pressure control valve and the pressure gauge.
The beneficial effects of the invention are as follows:
when the multi-concentration greenhouse gas calibration device with the vacuum purging function is used for calibrating a gas measuring instrument to be calibrated, the output of greenhouse gases with different known concentrations can be realized through the gas output device, so that the multi-sampling points of the gas concentration of the greenhouse gases are ensured, and the accuracy of a calibration fitting result is ensured;
the vacuum purging is adopted in the purging, the vacuum purging is carried out on the external connection cavity through the first vacuum pump, so that residual gas in the gas measuring instrument to be calibrated is rapidly purged, the purging efficiency and effect of the cavity of the equipment to be calibrated are improved, the switching between gases with different concentrations can be rapidly completed, the ventilation time between the gases with different concentrations is shortened, and the calibrating time is shortened;
the gas with specified concentration can pass through the equipment to be calibrated and maintain certain pressure through the gas output device, the output interface, the pressure interface, the second vacuum pump, the pressure control valve and the pressure gauge, namely the gas in the equipment to be calibrated has a pressure control function;
the greenhouse gas calibration device organically combines the output of greenhouse gases with different concentrations, vacuum purging and pressure control, solves the problems of low purging efficiency, long calibration time and poor purging effect of the greenhouse gas calibration device, and has the advantages of shorter calibration time and cleaner purging.
Drawings
FIG. 1 is a schematic diagram of a multi-concentration greenhouse gas scaling device with vacuum purging function according to the present invention.
FIG. 2 is a diagram showing the state of use of a multi-concentration greenhouse gas scaling device with vacuum purging function according to the present invention.
In the figure: 1. n (N) 2 The device comprises a gas cylinder, 2, an air cylinder, 3, a greenhouse gas cylinder, 4, a third adjustable throttle valve, 5, a third mass flowmeter, 6, a second adjustable throttle valve, 7, a second mass flowmeter, 8, an output interface, 9, a first adjustable throttle valve, 10, a first mass flowmeter, 11, a pressure gauge, 12, a pressure interface, 13, a first vacuum pump, 14, a two-position two-way valve, 15, a pressure control valve, 16, a second vacuum pump, 17, a third two-position two-way valve, 18, a second two-position two-way valve, 19, a first two-position two-way valve, 20 and equipment to be calibrated.
Detailed Description
The invention will be described in further detail with reference to the drawings and examples.
A multi-concentration greenhouse gas scaling device with a vacuum purging function is shown in fig. 1, and comprises a gas output device, wherein the gas output device is connected with one end of an output interface 8, the other end of the output interface 8 is used for being connected with a device to be scaled 20, and the gas output device is used for outputting greenhouse gases with different concentrations. The multi-concentration greenhouse gas scaling device also comprises a pressure gauge 11, a first vacuum pump 13, a two-position two-way valve 14, a pressure control valve 15, a second vacuum pump 16 and a pressure interface 12. One end of the pressure interface 12 is communicated with one end of the two-position two-way valve 14 and the first vacuum pump 13, the other end of the pressure interface 12 is used for being connected with the equipment to be calibrated 20, the other end of the two-position two-way valve 14 is connected with the pressure control valve 15, and the pressure control valve 15 is connected with the second vacuum pump 16. A pressure gauge 11 is arranged between the two-position two-way valve 14 and the pressure interface 12. In use of the scaling device, both the output port 8 and the pressure port 12 are connected to the chamber of the device 20 to be scaled, as shown in fig. 2.
The two-position two-way valve 14 and the pressure interface 12 are connected through a first gas transmission pipeline, one end of the first gas transmission pipeline is connected with the two-position two-way valve 14, and the other end of the first gas transmission pipeline is connected with the pressure interface 12. A pressure gauge 11 is provided on the first gas transfer line for measuring the fluid pressure in the first gas transfer line. The first vacuum pump 13 is connected to a first gas transmission line. The shape of the first gas transfer conduit is not limited. The two connection ports of the two-position two-way valve 14 are connected to the first gas transmission pipe and the second gas transmission pipe, respectively. One end of the second gas transmission pipeline is connected with a two-position two-way valve 14, and the other end is connected with a pressure control valve 15. The pressure control valve 15 is connected to the second vacuum pump 16, and specifically, is connected to the second vacuum pump 16 through a third gas transmission pipeline, and the pressure control valve 15 is used for controlling and adjusting the pressure of the gas flow. The first vacuum pump 13 and the second vacuum pump 16 are used for pumping out the gas in the equipment to be calibrated 20, the first vacuum pump 13 is used for vacuum purging the equipment to be calibrated 20, and the second vacuum pump 16 is used for controlling the air pressure in the equipment to be calibrated 20.
Preferably, a pressure gauge 11 is located between the first vacuum pump 13 and the pressure port 12, the pressure gauge 11 being able to detect the gas pressure in the first gas transmission line when the device 20 to be calibrated is evacuated.
As a preferable mode, the gas output device can output greenhouse gas with continuous concentration, through the design, the problem that calibration fitting results are inaccurate due to the fact that sampling points of the concentration of the greenhouse gas are too few is solved, and the applicability of the calibration device is improved.
The gas output device comprises N 2 A gas output mechanism, an air output mechanism and a greenhouse gas output mechanism. N (N) 2 The gas output mechanism, the air output mechanism and the greenhouse gas output mechanism all output gas to the equipment to be calibrated 20 through the output interface 8. N (N) 2 The gas output mechanism comprises N connected in sequence 2 The gas cylinder 1, the first two-way valve 19, the first adjustable throttle valve 9 and the first mass flow meter 10. The air output mechanism comprises an air cylinder 2, a second two-position two-way valve 18, a second adjustable throttle valve 6 and a second mass flowmeter 7 which are connected in sequence. The greenhouse gas output mechanism comprises a greenhouse gas cylinder 3, a third two-position two-way valve 17, a third adjustable throttle valve 4 and a third mass flowmeter 5 which are sequentially connected, wherein the greenhouse gas cylinder 3 is CH in the embodiment 4 The air cylinder 2 adopts the existing air storage tank which can be purchased. The third mass flowmeter 5, the second mass flowmeter 7 and the first mass flowmeter 10 are all connected with the output interface 8.
The scaling device is connected with the equipment to be scaled 20 through the output interface 8 and the pressure interface 12, and the specific operation process of the scaling device is as follows:
the device 20 to be calibrated is vacuum purged: (closing the output interface 8) confirming that the output interface 8 is in a closed state, then opening the pressure interface 12, ensuring that the two-position two-way valve 14 is in a closed state, opening the first vacuum pump 13, and enabling the first vacuum pump 13 to be in an open state until the pressure of the device 20 to be calibrated is pumped to 10Pa (not higher than 10 Pa); finally, the device 20 to be calibrated is ventilated with the outside, or the output interface 8 is opened to enable the gas (or high-purity nitrogen) with the concentration to be calibrated to be introduced into the device 20 to be calibrated, so that the device 20 to be calibrated is restored to the normal atmospheric pressure state. The vacuum purge of the device 20 to be calibrated is completed by repeating the process a plurality of times.
The multi-concentration greenhouse gas scaling apparatus of the present invention has a pressure control function for the gas in the device 20 to be scaled. The control method of the air pressure in the device to be calibrated 20 is as follows: when the gas output device is operated, the two-position two-way valve 14 is opened to an open state, the second vacuum pump 16 is started, and the pressure of the equipment to be calibrated 20 is controlled to be a specified value through the cooperation of the pressure control valve 15 and the pressure gauge 11.
The multi-concentration greenhouse gas scaling device of the present invention can realize the gas output of multi-concentration greenhouse gases to the equipment 20 to be scaled. The control of the gas concentration of the room gas to be measured is realized by an air output mechanism and a greenhouse gas output mechanism, and the greenhouse gas cylinder 3 is stored as
The flow rate of the second mass flowmeter 7 is +.>
The method comprises the steps of carrying out a first treatment on the surface of the The flow of the third mass flowmeter 5 is +.>
The method comprises the steps of carrying out a first treatment on the surface of the The gas concentration of the greenhouse gas output by the output interface 8 can be obtained>
The method comprises the following steps:
and (3) obtaining a parameter setting relation of the output of the greenhouse gases with different concentrations according to the calculation of the formula (1).
According to the multi-concentration greenhouse gas calibration device with the vacuum purging function, the vacuum purging is adopted, the vacuum purging is carried out on the cavity of the equipment to be calibrated 20 which is externally connected through the first vacuum pump 13, and residual gas in the gas measurement instrument to be calibrated can be rapidly purged through the first vacuum pump 13 of the multi-concentration greenhouse gas calibration device, so that the next concentration greenhouse gas can be rapidly calibrated, the purging efficiency of the cavity of the equipment to be calibrated 20 is improved, the switching between gases with different concentrations can be rapidly completed, and the ventilation time between gases with different concentrations is shortened. After the first vacuum pump 13 is purged, the second vacuum pump 16, the pressure control valve 15 and the pressure gauge 11 are used for testing the testing chamber of the equipment 20 to be calibrated, so that the gas with specified concentration passes through and maintains certain pressure, and the testing precision is ensured to a certain extent. The calibration device is provided with a pressure interface 12 and an output interface 8, and the two interfaces can be quickly replaced aiming at interfaces of different gas measuring devices, so that the calibration device has wider application range.
Each path of gas of the gas output device comprises a two-position two-way valve, an adjustable throttle valve and a mass flowmeter, the proportion of greenhouse gases with different concentrations can be completed through the mass flowmeter, and methane gas can be mixed into gas with specified concentration to be output.
The sampling points of the existing greenhouse gas concentration are too few, so that the calibration fitting result is inaccurate. When the gas measuring instrument to be calibrated is calibrated, the greenhouse gases with different known concentrations can be output through the gas output device capable of outputting the greenhouse gases with continuous concentrations, the calibration time of the calibration device is shortened by the gas output device, and the applicability of the calibration device is improved. The design of the adjustable throttle valve and the mass flowmeter realizes multiple gas concentration sampling points, and improves the accuracy of the calibration fitting result.
When the existing greenhouse gas calibration device is used for calibrating, the greenhouse gas calibration concentration gases are mutually interfered, and a high-purity nitrogen blowing or next calibration concentration gas blowing mode is generally adopted in the calibration process to ensure that no raw gas residue exists in the gas chamber, but the calibration mode is extremely easy to cause the mutual interference between the two calibration concentration gases, so that the final instrument precision is influenced.
Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (7)
1. The multi-concentration greenhouse gas calibration device with the vacuum purging function is characterized by comprising a gas output device and a pressure interface (12), wherein the gas output device is connected with the output interface (8) and is used for outputting greenhouse gases with different concentrations; the pressure interface (12) is communicated with one end of the two-position two-way valve (14) and the first vacuum pump (13), a pressure gauge (11) is arranged between the two-position two-way valve (14) and the pressure interface (12), the other end of the two-position two-way valve (14) is connected with the pressure control valve (15), and the pressure control valve (15) is connected with the second vacuum pump (16).
2. The multi-concentration greenhouse gas scaling apparatus with vacuum purging function as recited in claim 1, wherein the gas output means is capable of outputting a continuous concentration of greenhouse gas.
3. A multi-concentration greenhouse gas scaling apparatus with vacuum purging function as recited in claim 1, wherein said gas output means comprises N 2 Gas output mechanism, air output mechanism and greenhouse gas output mechanism, said N 2 The gas output mechanism, the air output mechanism and the greenhouse gas output mechanism can all pass throughThe output interface (8) outputs a gas to the device (20) to be calibrated.
4. A multi-concentration greenhouse gas scaling apparatus with vacuum purging function as recited in claim 3, wherein said N 2 The gas output mechanism comprises N connected in sequence 2 The greenhouse gas output mechanism comprises a greenhouse gas cylinder (3), a third two-position two-way valve (17), a third adjustable throttle valve (4) and a third mass flowmeter (5) which are sequentially connected; the first mass flowmeter (10), the second mass flowmeter (7) and the third mass flowmeter (5) are all connected with the output interface (8).
5. A multi-concentration greenhouse gas scaling apparatus with vacuum purging function as claimed in claim 1, characterized in that the pressure gauge (11) is located between the first vacuum pump (13) and the pressure interface (12).
6. The multi-concentration greenhouse gas scaling apparatus with vacuum purging function as claimed in claim 1, wherein the method of vacuum purging the equipment (20) to be scaled by the multi-concentration greenhouse gas scaling apparatus is repeated a plurality of times as follows:
closing the output interface (8), opening the pressure interface (12), enabling the two-position two-way valve (14) to be in a closed state, opening the first vacuum pump (13), closing the first vacuum pump (13) when the air pressure in the equipment (20) to be calibrated is not higher than 10Pa, and enabling the equipment (20) to be calibrated to be ventilated with the outside or opening the output interface (8) to enable the air in the air output device to be ventilated into the equipment (20) to be calibrated, so that the equipment (20) to be calibrated is restored to a normal atmospheric pressure state.
7. A multi-concentration greenhouse gas scaling apparatus with vacuum purging function as claimed in claim 1, wherein the scaling apparatus is capable of controlling the air pressure in the equipment (20) to be scaled, and the scaling apparatus controls the air pressure in the equipment (20) to be scaled by: when the gas output device operates, the two-position two-way valve (14) is opened to an open state, the second vacuum pump (16) is started, and the air pressure of the equipment (20) to be calibrated is controlled to be a specified value through the cooperation of the pressure control valve (15) and the pressure gauge (11).
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310300745.9A CN116008487A (en) | 2023-03-27 | 2023-03-27 | Multi-concentration greenhouse gas calibration device with vacuum purging function |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310300745.9A CN116008487A (en) | 2023-03-27 | 2023-03-27 | Multi-concentration greenhouse gas calibration device with vacuum purging function |
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Citations (6)
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|---|---|---|---|---|
| CN103175589A (en) * | 2011-12-26 | 2013-06-26 | 新奥科技发展有限公司 | Measuring meter calibration device and method |
| CN103487593A (en) * | 2013-09-18 | 2014-01-01 | 中国科学院微电子研究所 | Gas analysis device and method |
| CN107881306A (en) * | 2017-11-24 | 2018-04-06 | 北京七星华创磁电科技有限公司 | A kind of control pressurer system and control method |
| CN109164054A (en) * | 2018-10-12 | 2019-01-08 | 中国科学院上海光学精密机械研究所 | Carbon dioxide concentration measurement scaling system device |
| CN109855925A (en) * | 2019-03-04 | 2019-06-07 | 上海交通大学 | The high vapour concentration aerosol on-line measurement device of the high temperature and pressure of bandgap calibration function |
| CN111610189A (en) * | 2020-07-03 | 2020-09-01 | 福州大学 | Optical calibration system and method for concentration of multi-component gas |
-
2023
- 2023-03-27 CN CN202310300745.9A patent/CN116008487A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103175589A (en) * | 2011-12-26 | 2013-06-26 | 新奥科技发展有限公司 | Measuring meter calibration device and method |
| CN103487593A (en) * | 2013-09-18 | 2014-01-01 | 中国科学院微电子研究所 | Gas analysis device and method |
| CN107881306A (en) * | 2017-11-24 | 2018-04-06 | 北京七星华创磁电科技有限公司 | A kind of control pressurer system and control method |
| CN109164054A (en) * | 2018-10-12 | 2019-01-08 | 中国科学院上海光学精密机械研究所 | Carbon dioxide concentration measurement scaling system device |
| CN109855925A (en) * | 2019-03-04 | 2019-06-07 | 上海交通大学 | The high vapour concentration aerosol on-line measurement device of the high temperature and pressure of bandgap calibration function |
| CN111610189A (en) * | 2020-07-03 | 2020-09-01 | 福州大学 | Optical calibration system and method for concentration of multi-component gas |
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Application publication date: 20230425 |