CN117110014A - Gas dilution sampling device - Google Patents
Gas dilution sampling device Download PDFInfo
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- CN117110014A CN117110014A CN202311306904.2A CN202311306904A CN117110014A CN 117110014 A CN117110014 A CN 117110014A CN 202311306904 A CN202311306904 A CN 202311306904A CN 117110014 A CN117110014 A CN 117110014A
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- gas
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- dilution
- flow path
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- 238000010790 dilution Methods 0.000 title claims abstract description 65
- 239000012895 dilution Substances 0.000 title claims abstract description 65
- 238000005070 sampling Methods 0.000 title claims abstract description 23
- 238000002347 injection Methods 0.000 claims description 11
- 239000007924 injection Substances 0.000 claims description 11
- 238000003113 dilution method Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 120
- 239000000523 sample Substances 0.000 description 67
- 239000003085 diluting agent Substances 0.000 description 11
- 238000007865 diluting Methods 0.000 description 6
- 238000004458 analytical method Methods 0.000 description 5
- 239000012470 diluted sample Substances 0.000 description 5
- 230000001276 controlling effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000001914 filtration Methods 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000004868 gas analysis Methods 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/38—Diluting, dispersing or mixing samples
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D1/00—Pipe-line systems
- F17D1/02—Pipe-line systems for gases or vapours
- F17D1/04—Pipe-line systems for gases or vapours for distribution of gas
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D3/00—Arrangements for supervising or controlling working operations
- F17D3/01—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of a product
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
The invention relates to the technical field of gas sampling, in particular to a gas dilution sampling device, which comprises a sample inlet flow path and a dilution gas inlet flow path, wherein the sample inlet flow path comprises two branches, and one branch of the sample inlet flow path is used for emptying sample gas; the other branch comprises a first electromagnetic valve, a first valve and a flow limiting pipe which are sequentially communicated to form a passage so as to realize the circulation of sample gas; the dilution gas inlet flow path comprises a mass flow controller and a second valve which are sequentially communicated, so that the circulation of dilution gas is realized; the device also comprises a three-way valve, wherein a first port of the three-way valve is communicated with one end of the flow limiting pipe; the second port is communicated with one end of the second valve to realize the mixing of the sample gas and the dilution gas. The scheme of the invention can maintain stable output flow in the gas dilution process and improve the accuracy of the diluted concentration of the sample gas.
Description
Technical Field
The present invention relates generally to the field of gas injection technology. More particularly, the invention relates to a sample gas dilution and injection device.
Background
The standard gas of high concentration is generally sold on the market, and when the standard gas of lower concentration is required to be used, the standard gas of high concentration is generally required to be diluted.
The current gas dilution instrument generally uses a flow meter to control the flow rate to dilute the high-concentration standard gas to obtain the lower-concentration standard gas, namely, the mixed gas with a specific dilution ratio is generated by controlling the flow rate.
For example, patent document with the publication number CN211602649U, entitled "a gas dilution device", discloses a gas dilution device comprising a standard gas flow path and a dilution gas flow path, each flow path comprising a valve, a damper tube and a pressure sensor, both flow paths being subjected to gas dilution by means of a three-way valve, a pressure sensor, and an electromagnetic valve. This solution allows dilution of the standard gas.
However, it should be noted that, the dilution of the gas is performed only by the valve, the damper pipe, etc., and the accuracy of the mixed gas may be greatly reduced with the increase of the dilution factor, resulting in inaccurate gas distribution.
Therefore, the accuracy of the standard gas with lower concentration obtained by dilution of the existing gas dilution instrument is not high, and the accurate quantitative requirement in experimental operation cannot be completely met.
Disclosure of Invention
In order to solve one or more of the technical problems, the invention proposes that the stability of the mixed gas phase can be ensured by arranging the flow limiting pipe on the sample inlet flow path, and meanwhile, the accuracy of the mixed diluted sample gas can be improved by combining the flow control of the mass flow controller on the diluted gas; to this end, the present invention provides a solution in one aspect as follows.
The invention provides a gas dilution sampling device, which comprises a sample inlet flow path and a dilution gas inlet flow path, wherein the sample inlet flow path comprises two branches, and one branch of the sample inlet flow path is used for emptying sample gas;
the other branch comprises a first electromagnetic valve, a first valve and a flow limiting pipe which are sequentially communicated to form a passage so as to realize the circulation of sample gas;
the dilution gas inlet flow path comprises a mass flow controller and a second valve which are sequentially communicated, so that the circulation of dilution gas is realized;
the device also comprises a three-way valve, wherein a first port of the three-way valve is communicated with one end of the flow limiting pipe; the second port is communicated with one end of the second valve to realize the mixing of the sample gas and the dilution gas.
In one embodiment, one branch of the sample inlet path includes a second solenoid valve.
In one embodiment, the three-way valve is a dead-volume free three-way junction valve.
In one embodiment, the first valve is a pressure relief valve.
In one embodiment, the second valve is a one-way valve.
In one embodiment, the gas dilution sampling device further comprises a temperature controller for controlling the temperature of the pressure reducing valve, the flow limiting pipe and the three-way valve, so as to ensure the stability of the sample gas.
In one embodiment, the gas dilution sampling device further comprises a controller, and the controller is respectively connected with the mass flow controller, the first electromagnetic valve, the second electromagnetic valve and the temperature controller in a control mode.
The beneficial effects of the invention are as follows:
according to the scheme, the flow rate of the sample gas is controlled by adopting the flow limiting pipe to replace the mass flow controller, and when the same pressure is introduced into the front end of the flow limiting pipe, the outlet flow rate of the flow limiting pipe can keep stable output flow rate, so that the stability of the mixed gas phase is ensured; and then mixing the sample with the diluent gas through the three-way valve, so that the sample residue can be reduced, and the durability of the sample injection device can be improved.
Meanwhile, according to the scheme of the invention, the mass flow controller is not adopted in the sample inlet flow path, so that the limitation of the mass flow controller on sample gas can be avoided, and the method can be suitable for sample injection of various sample gases.
Furthermore, the gas dilution sampling device has the function of temperature regulation, and can further ensure the gas phase stability of the output diluted sample gas.
Drawings
The above, as well as additional purposes, features, and advantages of exemplary embodiments of the present invention will become readily apparent from the following detailed description when read in conjunction with the accompanying drawings. In the drawings, embodiments of the invention are illustrated by way of example and not by way of limitation, and like reference numerals refer to similar or corresponding parts and in which:
FIG. 1 schematically illustrates a schematic piping diagram of a gas dilution sampling apparatus of the present invention;
FIG. 2 schematically shows a control block diagram of a gas dilution sampling apparatus of the present invention;
reference numerals: 1. a sample gas inlet; 2. a dilution gas inlet; 3. a sample vent; 4. removing an analyzer port; 5. a first temperature control zone; 6. a flow limiting pipe; 7. a three-way valve; 8. a second temperature control zone; 9. a first filter; 10. a second filter; 11. a mass flow controller; 12. a second valve; 13. a first electromagnetic valve; 14. a second electromagnetic valve; 15. a first valve.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.
In the gas phase, the concentration of the final mixture is obtained by mixing the flow rates of the sample gas and the diluent gas, and the obtained mixed sample gas is connected to an analysis instrument for subsequent detection and analysis.
The calculation formula of the obtained mixed sample gas concentration is as follows:
wherein,C2 is the final concentration of the mixture,M1 is the flow rate of the sample gas,M2 is the total flow of the dilution gas plus the sample gas,C1 is the original concentration of the sample gas.
Thus, it is possible to use the desired final concentrationC2, performing the following calculation to determine the diluent gas plus sample gasMTotal flow of 2:
。
the sample flow M1 is determined and controlled by the flow measuring device.
Thus, based on the above, the accuracy of the final concentration is directly related to the accuracy of the flow measurement.
The existing gas dilution device generally adopts two or more mass flow controllers to perform sample proportioning, which is obviously unsuitable for sample injection design, because the samples have certain pollutants or different components and cannot be suitable for dilution injection of different samples, and meanwhile, the problem that accurate dilution of gas samples is difficult to realize by controlling the flow by using the mass flow controllers is solved.
Based on the technical problems, the invention provides a gas dilution sampling device for diluting a gas sample so as to obtain accurate dilution concentration.
Fig. 1 schematically shows a schematic diagram of a gas dilution sampling apparatus according to the present invention. Fig. 2 schematically shows a control block diagram of a gas dilution sampling apparatus according to the present invention.
As shown in FIG. 1, the gas dilution sampling device provided by the invention comprises a sample inlet flow path and a dilution gas inlet flow path.
Wherein the sample inlet flow path comprises two branches; one branch of the sample inlet flow path is used for emptying sample gas; the other branch of the sample inlet flow path comprises a first electromagnetic valve 13, a first valve 15 and a flow limiting pipe 6 which are sequentially communicated to form a passage, so that the circulation of sample gas is realized. Wherein the first valve 15 is a pressure reducing valve.
One of the branches for the evacuation of the sample gas comprises a second solenoid valve 14.
In one embodiment, for the other branch of the sample inlet flow path, a first filter 9 is further provided before the first solenoid valve 13 for filtering the sample gas, filtering out impurities to obtain a higher purity sample gas.
The dilution gas inlet flow path comprises a mass flow controller 11 and a second valve 12 which are sequentially communicated so as to realize the circulation of the dilution gas. The second valve 12 is a one-way valve.
In one embodiment, for the dilution gas inlet flow path, a second filter 10 is further provided before the Mass Flow Controller (MFC) 11 for filtering the dilution gas, filtering out impurities, to obtain a higher purity dilution gas.
The gas dilution sampling device further comprises a three-way valve 7, and a first port of the three-way valve 7 is communicated with one end of the flow limiting pipe 6; the second port communicates with one end of the second valve 12 to effect mixing of the sample gas and the diluent gas. Specifically, the three-way valve 7 is a dead-volume-free three-way converging valve, and is provided with three ports, namely two inlets and one outlet; i.e. both the first port and the second port are inlets.
The flow-limiting pipe 6 is made of stainless steel and corrosion-resistant materials.
In the embodiment, the diluent gas enters the mass flow controller 11 through the diluent gas inlet 2 and the second filter 10, and enters the three-way valve 7 through the one-way valve, so as to prevent possible high-pressure sample gas from flowing into the mass flow controller 11 in a back-blowing manner; then the sample gas is divided into two paths, one path is flushed by a second electromagnetic valve 14 and then is emptied, and the other path is stabilized by a pressure reducing valve after passing through a first electromagnetic valve 13 and then sequentially enters a flow limiting pipe 6 and a three-way valve 7; since the diluent gas and the sample gas both enter the three-way valve 7, the diluent gas and the sample gas can be mixed at this time, and then the mixed diluent sample gas is input into the analysis instrument through the analyzer port 4.
Further, the gas dilution sampling device in this embodiment further includes a first temperature control area 5 for controlling the temperature of the pressure reducing valve, the flow limiting pipe 6, and the three-way valve 7, where the temperature control part of the first temperature control area 5 is mainly implemented by a temperature controller, a heating sleeve, or a heat tracing pipe, so as to ensure the stability of the sample gas. Specifically, the pressure reducing valve, the flow limiting pipe 6 and the three-way valve 7 adopt a temperature controller to control the temperature; the pipelines among the pressure reducing valve, the flow limiting pipe 6 and the three-way valve 7 can be heating sleeves or heat tracing pipes. In one embodiment, the thermostat in this embodiment may be a temperature heater.
Meanwhile, a second temperature control area 8 is arranged between the three-way valve 7 and the analyzer port 4, and the second temperature control area 8 mainly aims at a pipeline between the three-way valve 7 and the analyzer port 4, namely, the pipeline is set as a heat tracing pipe and is used for stabilizing the gas phase of the mixed diluted sample gas.
Further, the gas dilution sampling device further comprises a control panel, and a touch screen is arranged on the control panel; wherein, the mass flow controller 11, the first electromagnetic valve 13, the second electromagnetic valve 14, the touch screen and the temperature control part of the temperature controller can respectively set parameters through the touch screen and control the parameters through the controller.
The controller is arranged in the control panel, the touch screen realizes the control of the dilution of the gas sample through the controller, and specifically, as shown in fig. 2, the controller is respectively connected with the mass flow controller, the first electromagnetic valve, the second electromagnetic valve, the touch screen and the temperature controller in a control mode.
It should be noted that, in this embodiment, the pipeline is further provided with a pressure sensor and a temperature sensor connected to the controller, which are used for monitoring the pressure of the sample gas and the diluent gas on the pipeline and the temperature of the pipeline in real time, and the controller adjusts the flow rate and the temperature of the sample gas and the diluent gas according to the received pressure and temperature.
All parameters in the embodiment are controlled and monitored through the touch screen, so that the sample injection device is conveniently operated, and the requirements of testing and production can be met.
The working process of the gas dilution sampling device in the embodiment is as follows:
after the external pipeline of the equipment is connected, after the temperature of the system is stable, a diluting gas inlet flow path is opened, the flow of the mass flow controller 11 is adjusted according to the diluting proportion, the sample gas with pressure is connected, the touch screen on the control panel is clicked to start, at the moment, the controller firstly opens the second electromagnetic valve 14, passes through the sample discharging port 3, firstly discharges some sample gas for a short time (generally a few seconds), flushes and replaces part of pipelines, then closes the second electromagnetic valve 14, opens the first electromagnetic valve 13, samples through the first filter 9 and the pressure reducing valve, the sample gas passes through the flow limiting pipe 6, is mixed with the diluting gas after passing through the three-way valve 7, and the mixed diluting sample gas enters the analyzer after heat preservation after passing through the heat tracing pipe, so that the detection or analysis of the diluting sample gas is realized.
Before the gas sample is diluted, the flow rate of the flow restrictor 6 is set, specifically, the flow rate of the mass flow controller 11 is closed, standard gas is introduced into the sample gas inlet 1, a digital flowmeter is connected to the analyzer port 4, the pressure of the pressure reducing valve is regulated, when the outlet flow rate of the analyzer port 4 reaches the required flow rate, the pressure reducing valve is stopped to be regulated, and the regulating position of the pressure reducing valve is determined. The standard gas can be nitrogen or helium.
The gas dilution sampling device can be used for mixing high-concentration sample gas with dilution gas under the control of the controller so as to reduce the concentration of analysis components, so that the problem that a high-concentration sample needs to be analyzed but a detector signal overflows is solved, and the mixed dilution sample gas can be used for subsequent gas analysis.
According to the scheme, the stainless steel flow-limiting pipe is adopted to replace a mass flow controller to control the flow of sample gas, and when the same pressure is introduced into the front end of the flow-limiting pipe, the outlet flow of the flow-limiting pipe can keep stable output flow; and then the sample gas is mixed with the dilution gas through the three-way valve, so that the residual sample gas can be reduced, and the durability of the sample injection device can be improved.
Meanwhile, the mixed diluted sample gas is output through the constant temperature heat tracing pipe, so that the stability of the diluted sample gas is ensured.
It should be noted that the terms "first" or "second" and the like used in this specification are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present specification, the meaning of "plurality" means at least two, for example, two, three or more, etc., unless explicitly defined otherwise.
In the foregoing description of the present specification, the terms "coupled" and the like should be construed broadly unless otherwise specifically indicated and defined. For example, in terms of the term "coupled," it may be fixedly coupled, detachably coupled, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intermediaries, or in communication with each other or in interaction with each other. Therefore, unless otherwise specifically defined in the specification, a person skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.
While various embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Many modifications, changes, and substitutions will now occur to those skilled in the art without departing from the spirit and scope of the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention.
Claims (7)
1. The gas dilution sampling device comprises a sample inlet flow path and a dilution gas inlet flow path, and is characterized in that the sample inlet flow path comprises two branches, and one branch of the sample inlet flow path is used for emptying sample gas;
the other branch comprises a first electromagnetic valve, a first valve and a flow limiting pipe which are sequentially communicated to form a passage so as to realize the circulation of sample gas;
the dilution gas inlet flow path comprises a mass flow controller and a second valve which are sequentially communicated, so that the circulation of dilution gas is realized;
the device also comprises a three-way valve, wherein a first port of the three-way valve is communicated with one end of the flow limiting pipe; the second port is communicated with one end of the second valve to realize the mixing of the sample gas and the dilution gas.
2. The gas dilution and sample injection apparatus according to claim 1, wherein one branch of the sample inlet path comprises a second solenoid valve.
3. The gas dilution and sample-injection device according to claim 1, wherein the three-way valve is a dead-volume-free three-way confluence valve.
4. The gas dilution and sample injection device according to claim 1, wherein the first valve is a pressure reducing valve.
5. The gas dilution sampling apparatus of claim 4, wherein the second valve is a one-way valve.
6. The gas dilution sampling apparatus according to claim 4, further comprising a temperature controller for controlling the temperature of the pressure reducing valve, the flow limiting pipe, and the three-way valve to ensure the stability of the sample gas.
7. The gas dilution sampling apparatus of any one of claims 1-6, further comprising a controller in control connection with the mass flow controller, the first solenoid valve, the second solenoid valve, and the temperature controller, respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311306904.2A CN117110014A (en) | 2023-10-10 | 2023-10-10 | Gas dilution sampling device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311306904.2A CN117110014A (en) | 2023-10-10 | 2023-10-10 | Gas dilution sampling device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117110014A true CN117110014A (en) | 2023-11-24 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311306904.2A Pending CN117110014A (en) | 2023-10-10 | 2023-10-10 | Gas dilution sampling device |
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| Country | Link |
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| CN (1) | CN117110014A (en) |
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2023
- 2023-10-10 CN CN202311306904.2A patent/CN117110014A/en active Pending
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