Continuous gas pressurization sampling device

Abstract

The utility model provides a continuous gas pressurization sampling device which comprises a gas extraction passage and a sampling passage, a gas extraction pump is arranged on the gas extraction passage, a sampling pump is arranged on the sampling passage, and the two passages are both connected to a gas supply end. The sucking pump is kept to be started when the sampling device is in a working state, and the sampling pump is started when the sampling instrument samples. According to the scheme, a double-air-pump structure is adopted, it can be ensured that external fresh air is stably supplied to the sampling instrument in real time, the gas purity is not affected even if the length of the air inlet pipeline reaches hundreds of meters, and the air inlet pipeline is particularly suitable for being used in stations such as an automatic environment air monitoring station. According to the sampling device in the scheme, when the sampling device is in a normal operation state, the sucking pump is kept to be started, the sampling pump does not need to be started, and the sampling pump is started only when a sampling instrument needs to sample, so that the service life of the sampling pump is not influenced.

Description

Technical Field

[0001] The utility model relates to a gas sampling device, in particular to a continuous gas pressurization sampling device. Background Art

[0002] Continuous analysis of gas samples is often required in fields such as environmental protection and scientific research. Many analytical instruments, such as those based on gas chromatography-mass spectrometry (GC-MS), do not perform continuous sampling, with the injection time typically accounting for only a small fraction of the overall analysis time. The inlet remains closed between the completion of an injection and the start of the next one. Furthermore, these instruments typically require high injection pressures to function properly, necessitating continuous pressurization capabilities in the sampling device.

[0003] Currently, commonly used sampling devices typically have only one sampling pump, which is turned on when the gas sample is needed. However, in applications such as atmospheric monitoring stations, the sampling pipeline can be hundreds of meters long. If the sampling pump is only activated when the sample is needed, a considerable portion of the sampled gas will come from residual gas in the pipeline, affecting the accuracy of the analysis. If the sampling pump is left on all the time, the inlet will remain closed most of the time, causing the pump to be subject to high pressure, seriously shortening its lifespan.

[0004] Therefore, it is necessary to improve the existing sampling device to solve the above problems. Summary of the Invention

[0005] The technical problem to be solved by the utility model is that when the existing sampling device is used in a long sampling pipeline, the gas purity is low and the service life of the sampling pump is shortened, and thus a continuous gas pressurization sampling device is provided.

[0006] The technical solution of the present application provides a continuous gas pressurization sampling device, comprising a gas extraction path and a sampling path, wherein:

[0007] The air extraction passage is provided with an air extraction pump, the air inlet end of the air extraction passage is connected to the air supply end, the air outlet end of the air extraction passage is provided with a first exhaust port, and the air extraction pump is kept turned on when the sampling device is in a working state;

[0008] The sampling passage is connected between the air supply end and the air inlet end of the sampling instrument. A sampling pump is provided on the sampling passage, and the sampling pump is turned on when the sampling instrument is sampling.

[0009] In some schemes of the continuous gas pressurized sampling device, the sampling passage is also connected in parallel with a balancing branch; a back pressure valve is provided on the balancing branch, one end of the back pressure valve is connected to the air outlet of the sampling pump, and the other end of the back pressure valve is provided with a second exhaust port.

[0010] In some embodiments of the continuous gas pressurized sampling device, the air inlet of the sampling pump is connected to the air inlet of the vacuum pump.

[0011] In some embodiments of the continuous gas pressurized sampling device, a filter is further provided on the sampling passage, and the filter is provided between the gas supply end and the gas inlet of the sampling pump.

[0012] The continuous gas pressurization sampling device described in some embodiments further includes:

[0013] A pressure sensor is provided between the air outlet of the sampling pump and one end of the back pressure valve.

[0014] The continuous gas pressurization sampling device described in some embodiments further includes:

[0015] A first flow sensor is provided between the air supply end and the air inlet end of the air extraction passage.

[0016] The continuous gas pressurization sampling device described in some embodiments further includes:

[0017] A second flow sensor is provided at the air outlet end of the air pump.

[0018] The continuous gas pressurization sampling device described in some embodiments further includes:

[0019] A third flow sensor is provided between the air outlet of the sampling pump and the air inlet of the sampling instrument.

[0020] The continuous gas pressurization sampling device described in some embodiments further includes:

[0021] The branch flow sensor is arranged between the other end of the back pressure valve and the second exhaust port.

[0022] In some embodiments of the continuous gas pressurized sampling device, the sampling pathways include multiple pathways, and different sampling pathways are connected in parallel.

[0023] Compared with the prior art, the above technical solution provided by this application has at least the following technical effects:

[0024] The continuous gas pressurized sampling device provided in the present application includes an exhaust passage and a sampling passage. An exhaust pump is provided on the exhaust passage, and a sampling pump is provided on the sampling passage. Both passages are connected to the gas supply end. The exhaust pump remains turned on when the sampling device is in working state, and the sampling pump is turned on when the sampling instrument is sampling. The present application adopts a dual air pump structure, which can ensure that the external fresh atmosphere is supplied to the sampling instrument in real time and stably. The air intake pipeline length of hundreds of meters does not affect the gas purity. It is particularly suitable for use in sites such as automated environmental air monitoring stations. The sampling device in this solution only needs to keep the exhaust pump turned on during normal operation, and the sampling pump does not need to be turned on. The sampling pump is only turned on when the sampling instrument needs to take samples. Therefore, the service life of the sampling pump will not be affected. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a structural diagram of a continuous gas pressurization sampling device according to an embodiment of the present application;

[0026] Figure 2 This is a structural diagram of a continuous gas pressurization sampling device according to another embodiment of the present application;

[0027] Figure 3 This is a structural diagram of a continuous gas pressurization sampling device according to another embodiment of the present application;

[0028] Figure 4 This is a structural diagram of a continuous gas pressurization sampling device according to another embodiment of the present application;

[0029] The meanings of the reference numerals are as follows:

[0030] 10-intake end;

[0031] 100-air extraction passage, 101-air extraction pump, 102-first exhaust port;

[0032] 200 - sampling channel, 201 - sampling pump, 202 - back pressure valve, 203 - second exhaust port, 204 - filter, 205 - pressure sensor, 206 - first flow sensor, 207 - branch flow sensor, 208 - third flow sensor;

[0033] 30-Air inlet of sampling instrument. DETAILED DESCRIPTION

[0034] The specific implementation of this application is further described below with reference to the accompanying drawings.

[0035] It is easy to understand that according to the technical solution of this application, a variety of structural methods and implementation methods can be replaced with each other by those skilled in the art without changing the essential spirit of this application. Therefore, the following specific embodiments and drawings are only exemplary descriptions of the technical solution of this application and should not be regarded as the entire application or as a limitation or restriction of the technical solution of the application.

[0036] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly mentioned in this specification are defined relative to the structure shown in the drawings. They are relative concepts and may vary depending on the location and usage of the device. Therefore, these or other directional terms should not be interpreted as restrictive.

[0037] This embodiment provides a continuous gas pressurization sampling device, such as Figure 1 As shown, it includes an air extraction passage 100 and a sampling passage 200. The air extraction passage 100 is provided with an air extraction pump 101, the air inlet end of the air extraction passage 100 is connected to the air supply end 10, and the air outlet end of the air extraction passage 100 is provided with a first exhaust port 102. The air extraction pump 101 remains open when the sampling device is in working state; the sampling passage 200 is connected between the air supply end 10 and the air inlet end 30 of the sampling instrument, and the sampling passage 200 is provided with a sampling pump 201. The sampling pump 201 is turned on when the sampling instrument is sampling. That is, the continuous gas pressurization sampling device includes two air pumps, the air extraction pump 101 and the sampling pump 201. The air extraction pump 101 is in a normally open state and is used to continuously extract gas samples from the outside. The sampling pump 201 is turned on when sampling is required, and extracts part of the gas from the air flow of the air extraction pump 101 and provides it to the analysis instrument.

[0038] In the above scheme, connecting pipelines are provided between different components for realizing gas transmission. The connecting pipelines are used to connect the interfaces of each component and provide gas channels. Commonly used pressure-resistant gas pipelines, such as stainless steel pipes, copper pipes, polymer pipes, etc., can be used in this scheme. In actual application, the selection should be made according to the actual conditions such as the type of sampling gas, injection pressure, type of interface, etc., and contamination of the sample should be avoided while meeting the sampling conditions. When sampling ambient air, a stainless steel pipe with a polished inner surface can be used as a connecting pipeline. When sampling corrosive gases such as flue gas, a stainless steel pipe with a passivated inner surface can be used as a connecting pipeline.

[0039] The continuous gas pressurized sampling device in the above embodiment includes an air extraction passage 100 and a sampling passage 200. An air extraction pump 101 is provided on the air extraction passage 100, and a sampling pump 201 is provided on the sampling passage 200. Both passages are connected to the gas supply end 10. The air extraction pump 101 remains turned on when the sampling device is in working state, and the sampling pump 201 is turned on when the sampling instrument is sampling. The above scheme adopts a dual air pump structure, which can ensure that the external fresh atmosphere is supplied to the sampling instrument in real time and stably. The air intake pipeline length of hundreds of meters does not affect the gas purity. It is particularly suitable for use at sites such as automated environmental air monitoring stations. The sampling device in this scheme only needs to keep the air extraction pump 101 turned on during normal operation, and the sampling pump 201 does not need to be turned on. The sampling pump 201 is only turned on when the sampling instrument needs to take samples. Therefore, the service life of the sampling pump 201 will not be affected. This scheme can provide continuous fresh pressurized gas samples to the analytical instrument at any time without shortening the life of the sampling pump.

[0040] As a preferred solution, Figure 2 As shown, the sampling path 200 is also connected in parallel with a balancing branch; a back-pressure valve 202 is provided on the balancing branch. One end of the back-pressure valve 202 is connected to the outlet of the sampling pump 201, and the other end of the back-pressure valve 202 is provided with a second exhaust port 203. The provision of the balancing branch allows the pressure in the sampling path to be balanced, preventing excessive pressure therein. When the pressure in the sampling path is too high, it can be exhausted to the second exhaust port 203 through the branch.

[0041] Furthermore, if Figure 1 and Figure 2 As shown, the air inlet of the sampling pump 201 is connected to the air inlet of the air extraction pump 101. That is, the sampling pump 201 samples from the upstream air flow of the air extraction pump 101, which can avoid the risk of contamination of the collected gas sample by the air extraction pump 101.

[0042] In some schemes, such as Figure 3 As shown, in the continuous gas pressurized sampling device, a filter 204 is further provided on the sampling passage 200, and the filter 204 is provided between the gas supply end 10 and the air inlet of the sampling pump 201. The filter 204 is used to filter particulate matter in the air flow to protect the sampling pump 201 and the downstream sampling instrument. The filter 204 can be a filter commonly used in scientific research instruments, such as a polytetrafluoroethylene filter, a metal sintered filter, etc. Further preferably, the filter 204 can also be installed at the front end of the air inlet pipeline of the vacuum pump 201 to protect the vacuum pump 101 and reduce the load on the inlet filter of the sampling pump 201.

[0043] Preferably, if Figure 3As shown, the continuous gas pressurization sampling device further includes a pressure sensor 205, which is disposed between the gas outlet of the sampling pump 201 and one end of the back pressure valve 202. The pressure sensor 205 is used to measure the pressure at the gas inlet end 30 of the sampling instrument to monitor the sampling pressure. The pressure sensor 205 can be a common pressure measuring instrument, such as a mechanical pressure gauge or a pressure transmitter.

[0044] In some preferred embodiments, the continuous gas pressurization sampling device further includes a first flow sensor 206, which is disposed between the gas supply end 10 and the gas inlet end of the gas extraction passage. The first flow sensor 206 is disposed at the outlet of the gas supply end 10 and is capable of monitoring the gas extraction flow and the sampling flow. Furthermore, the continuous gas pressurization sampling device may further include a second flow sensor, which is disposed at the gas outlet end of the gas extraction pump 101. The second flow sensor can monitor the working status of the gas extraction pump 101 to prevent the gas extraction pump 101 from overloading.

[0045] Preferably, the continuous gas pressurization sampling device further includes a branch flow sensor 207 disposed between the other end of the back pressure valve 202 and the second exhaust port 203. The branch flow sensor 207 is used to monitor the flow of the balancing branch and the working status of the back pressure valve 202.

[0046] Preferably, the continuous gas pressurized sampling device further includes a third flow sensor 208, which is disposed between the gas outlet of the sampling pump 201 and the gas inlet 30 of the sampling instrument. The third flow sensor 208 is used to monitor the sampling flow rate and the working status of the sampling pump 201.

[0047] In the above solution, there can be one or more sampling paths 200. When there are multiple sampling paths 200, the sampling paths 200 are not connected in parallel. Based on the above principle, it is possible to provide gas sampling for multiple analytical instruments at the same time.

[0048] As needed, the above technical solutions can be combined to achieve the best technical effect.

[0049] The above are only the principles and preferred embodiments of the present application. It should be noted that, for those skilled in the art, on the basis of the principles of the present application, several other modifications can be made, which should also be considered as the scope of protection of the present application.

Claims

1. A continuous gas pressurized sampling device, characterized in that: It includes an exhaust passage and a sampling passage, wherein: The air extraction passage is provided with an air extraction pump, the air inlet end of the air extraction passage is connected to the air supply end, the air outlet end of the air extraction passage is provided with a first exhaust port, and the air extraction pump is kept turned on when the sampling device is in a working state; The sampling passage is connected between the air supply end and the air inlet end of the sampling instrument. A sampling pump is provided on the sampling passage, and the sampling pump is turned on when the sampling instrument is sampling.

2. The continuous gas pressurization sampling device according to claim 1, characterized in that: The sampling path is further connected in parallel with a balancing branch; A back pressure valve is provided on the balancing branch, one end of the back pressure valve is connected to the air outlet of the sampling pump, and the other end of the back pressure valve is provided with a second exhaust port.

3. The continuous gas pressurization sampling device according to claim 2, characterized in that: The air inlet of the sampling pump is communicated with the air inlet of the air extraction pump.

4. The continuous gas pressurization sampling device according to claim 3, characterized in that: The sampling passage is further provided with a filter, and the filter is arranged between the air supply end and the air inlet of the sampling pump.

5. The continuous gas pressurization sampling device according to any one of claims 2 to 4, characterized in that: Also includes: A pressure sensor is provided between the air outlet of the sampling pump and one end of the back pressure valve.

6. The continuous gas pressurization sampling device according to claim 5, characterized in that: Also includes: A first flow sensor is provided between the air supply end and the air inlet end of the air extraction passage.

7. The continuous gas pressurization sampling device according to claim 6, characterized in that: Also includes: A second flow sensor is provided at the air outlet end of the air pump.

8. The continuous gas pressurization sampling device according to claim 7, characterized in that: Also includes: A third flow sensor is provided between the air outlet of the sampling pump and the air inlet of the sampling instrument.

9. The continuous gas pressurization sampling device according to claim 8, characterized in that: Also includes: The branch flow sensor is arranged between the other end of the back pressure valve and the second exhaust port.

10. The continuous gas pressurization sampling device according to claim 9, characterized in that: The sampling paths include a plurality of paths, and different sampling paths are connected in parallel.

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