Gas sampling and analyzing device

Abstract

The invention belongs to the technical field of gas sampling detection, and discloses a gas sampling analysis device, which comprises a gas storage bottle and a recovery assembly, the recovery assembly comprises a piston, and the piston is slidably arranged in the gas storage bottle; the first chamber is defined by the piston and the gas storage cylinder; the second chamber is defined by the piston and the gas storage cylinder, and the pressure intensity of the second chamber is larger than that of the first chamber; the pressure relief unit is used for relieving pressure of the second cavity; the pressure relief unit comprises an exhaust hole and an exhaust valve, the exhaust hole is formed in the bottle body of the gas storage bottle, the exhaust hole is communicated with the second cavity, and the exhaust valve is communicated with the exhaust hole; according to the scheme, the piston is arranged in the gas storage bottle, and the pressure relief unit is used for relieving the pressure of the second cavity, so that residual sample gas in a pipeline can be sucked into the gas storage bottle through negative pressure difference after the compressor is closed; the problem that sample gas remains in a pipeline of an existing sampling device is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas sampling and detection, and specifically relates to a gas sampling and analysis device. Background Art

[0002] See "Development and Application of Standard Mixed Gas Shaking Device for Chromatographic Test" (Jiang Rongrong, Wang Boying, Yang Junqiu, et al. Development and Application of Standard Mixed Gas Shaking Device for Chromatographic Test [J]. Mechanical and Electrical Engineering Technology, 2024, 53 (02): 283-2286). Before the gas chromatograph is used to test the content of dissolved gas components in oil, the gas chromatograph is generally calibrated using an external standard quantitative method using a standard mixed gas with known concentrations of each component. The calibration test must meet the repeatability of two adjacent calibrations within ±1.5% of the average value, otherwise the calibration must be repeated, and the content of each component in the sample to be tested is calculated based on the calibration test results.

[0003] Referring to the document with the existing publication (announcement) number CN113804518A, a high-fidelity sampling device for high-purity and ultra-pure gas and a sampling method thereof are disclosed. The device includes a high-pressure gas storage cylinder and a first pipeline and a second pipeline respectively connected to the outlet end and the inlet end of the high-pressure gas storage cylinder, and also includes a vacuum generator with an inhalation chamber. The other end of the first pipeline can be connected to a gas analyzer. The first pipeline is respectively provided with a second micro-regulating valve and a pressure gauge. The second pipeline is provided with a first micro-regulating valve. The other end of the second pipeline is connected to the induced air inlet of the vacuum generator. A third pipeline is led out from the second pipeline between the first micro-regulating valve and the inlet end of the high-pressure gas storage cylinder. The mixed gas outlet of the vacuum generator is connected to the inlet of the fourth pipeline. A three-way valve is provided on the fourth pipeline. The other end of the third pipeline is connected to the first end of the three-way valve. The second end of the three-way valve is connected to the mixed gas outlet of the vacuum generator. The third end of the three-way valve is communicated with the atmosphere. A Laval nozzle is provided at the sample gas inlet.

[0004] For example, the gas cylinder of the sampling device mentioned above, when sending the sample gas into the gas cylinder, an external pipeline is connected to the inlet joint of the gas cylinder, and then the pipeline is connected to the compressor, and finally the sample gas is filled into the gas cylinder through the pipeline. After the gas is sent into the gas cylinder, the compressor needs to be turned off, but turning off the compressor will cause the gas in the pipeline to lose the high-pressure source provided by the outside, making the pressure in the pipeline smaller. Because there is sample gas in the gas cylinder, its internal pressure is higher than the pressure in the pipeline, resulting in the gas in the pipeline cannot enter the gas cylinder. At the same time, in order to meet the needs of the gas cylinder, the pipeline needs to be disassembled in the end. This results in residual sample gas in the pipeline, resulting in waste of sample gas. Summary of the invention

[0005] The purpose of this solution is to provide a gas sampling and analysis device to solve the problem of sample gas remaining in the pipeline of the existing sampling device.

[0006] In order to achieve the above object, the present invention provides a gas sampling and analysis device, including a gas storage cylinder and a recovery component, wherein the recovery component includes: A piston, wherein the piston is slidably disposed in the gas storage cylinder; A first chamber, wherein the first chamber is a first chamber formed by the piston and the gas storage bottle; A second chamber, wherein the second chamber is formed by the piston and the gas cylinder, and the pressure of the second chamber is greater than the pressure of the first chamber; A pressure relief unit, the pressure relief unit is used to relieve pressure in the second chamber; A pressurizing unit is used to pressurize the second chamber.

[0007] The principle of this scheme is as follows: (1) The piston divides the internal space of the gas cylinder into a first chamber and a second chamber, so that the gas in the gas cylinder is stored in the first chamber. When the sample gas needs to be filled into the gas cylinder, the outlet of the gas cylinder is connected to the compressor through a pipeline, and the compressor is connected to the sample gas supply equipment through a pipeline. Then, the valve and the compressor at the outlet of the gas cylinder are opened in turn to fill the external sample gas into the first chamber. After the sample gas is filled into the gas cylinder, the compressor needs to be turned off, the pipeline loses the high-pressure source, and the pressure in the second chamber is relieved through the pressure relief unit, so that the pressure in the second chamber is reduced, thereby increasing the volume of the first chamber to generate negative pressure, and then the sample gas remaining in the pipeline is sucked into the first chamber, thereby recovering the gas remaining in the pipeline. Finally, the valve at the outlet of the gas cylinder is closed, and the pipeline and other equipment connected to the outlet are disassembled, and the sample gas is stored in the gas cylinder. (2) During sampling and analysis, the sampling device is connected to the valve at the outlet of the gas cylinder through a pipeline, and then the valve is opened to pressurize the second chamber through the pressurizing unit, thereby increasing the pressure in the second chamber, thereby reducing the volume of the first chamber, and the gas in the first chamber is filled into the sampling device from the outlet under the push of the piston. After the gas is collected, the pressure in the second chamber is relieved through the pressure relief unit to recover the residual gas in the pipeline.

[0008] The effects of this solution are as follows: (1) In the traditional sampling process, turning off the compressor will cause the pipeline to lose the high-pressure source, so that the gas in the pipeline cannot enter the gas storage bottle. This solution can use the piston set in the gas storage bottle and use the pressure relief unit to relieve the pressure in the second chamber. After turning off the compressor, the sample gas remaining in the pipeline can be sucked into the gas storage bottle through the negative pressure difference, thereby avoiding the waste of gas in the pipeline. (2) After sampling, the gas in the first chamber is partially discharged. When the volume of the first chamber remains unchanged, the distance between gas molecules will increase and the density of the gas will decrease. This means that the number of gas molecules per unit volume decreases. This will affect the concentration and pressure of the sample gas, because the pressure of the gas is related to its density and temperature. According to the ideal gas law (PV=nRT), when the temperature and gas volume remain unchanged, an increase in volume will lead to a decrease in pressure. In standard gas sampling, the standard gas used to calibrate the analytical instrument is crucial to the test accuracy of the instrument, so it is necessary to keep the density of the gas unchanged during sampling. In this solution, by pressurizing the second chamber, the piston moves toward the gas outlet end of the gas storage tank, thereby reducing the volume of the first chamber to avoid reducing the density of the gas.

[0009] Furthermore, the pressure relief unit includes an exhaust hole and an exhaust valve, the exhaust hole is arranged on the body of the gas storage bottle, the exhaust hole is communicated with the second chamber, and the exhaust valve is communicated with the exhaust hole.

[0010] The principle and effect of this solution are: when it is necessary to recover the residual gas in the pipeline, open the exhaust valve to reduce the volume of the second chamber, increase the volume of the first chamber, and make the first chamber generate negative pressure to inhale the sample gas remaining in the pipeline.

[0011] Furthermore, it also includes a sampling component, which includes a sampling tube and a bellows, one end of the bellows is connected to the gas outlet end of the gas storage bottle, the free end of the bellows is connected to the sampling tube, the free end of the sampling tube is connected to the piston, and the sampling tube is provided with a sampling port.

[0012] The principle and effect of this scheme are: the piston drives the sampling tube to move, thereby compressing or stretching the bellows, increasing or decreasing the volume of the first chamber, and the sample gas enters or exits the bellows and the sampling tube from the externally connected pipe, and then enters into the gas storage bottle or is discharged from the gas storage bottle from the sampling port.

[0013] Furthermore, there are multiple sampling ports, and the multiple sampling ports are arranged at intervals along the axis of the sampling tube.

[0014] The principle and effect of this scheme are: due to the different densities of the components of the standard mixed gas, the concentration of the mixed gas taken out deviates from the accurate concentration of the standard gas, especially the extremely low density hydrogen, which tends to gather on the top of the standard gas bottle. Ensuring that the calibration test results meet the repeatability and accuracy requirements is a key link in gas chromatography analysis. Since this scheme has multiple sampling ports at intervals, they can correspond to gases of different densities respectively, and can perform stratified sampling of gases of different densities, so that the sampling results are closer to the actual concentration of the standard mixed gas.

[0015] Furthermore, it also includes a stirring component, which includes fan blades and a driving unit for driving the fan blades to rotate, the fan blades are arranged on the sampling tube, the sampling tube is rotatably connected to the piston, the sampling tube is connected to a rotary joint, and the other end of the rotary joint is rotatably connected to the bellows.

[0016] The principle and effect of this solution are as follows: Experiments have shown that shaking the standard mixed gas in the gas cylinder before the test can make the calibration test results closer to the concentrations of each component marked, and it is easier to meet the repeatability requirements, making the results of the gas chromatography test more accurate. When sampling, this solution drives the fan blades to rotate through the drive unit to fully mix the gases of different densities in the gas cylinder.

[0017] Furthermore, the driving unit includes a threaded sleeve and a threaded tube, the threaded sleeve is threadedly connected to the threaded tube, the threaded sleeve is fixedly connected to the inner wall of the gas storage bottle, and the threaded tube is fixedly arranged on the outer wall of the sampling tube.

[0018] The principle and effect of this scheme are: when sampling, the booster unit boosts the pressure of the second chamber, causing the piston to push the sampling tube toward the gas outlet end of the gas storage tank, thereby making the threaded tube cooperate with the threaded sleeve, so that the threaded tube drives the fan blades on the sampling tube to rotate, thereby stirring and mixing the stratified gas.

[0019] Furthermore, the boosting unit includes an air inlet hole and an air inlet valve, the air inlet hole is arranged on the body of the gas storage bottle, the air inlet hole is communicated with the second chamber, and the air inlet hole is communicated with the air inlet valve.

[0020] The principle and effect of this solution is that air is inflated into the air inlet hole through the air inlet valve, thereby increasing the volume of the second chamber to drive the sampling tube to move. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The figure is a schematic diagram of the structure of a gas sampling and analyzing device of the present invention.

[0022] The figure marks in the drawings of the specification include: gas storage cylinder 1, recovery component 2, piston 21, first chamber 22, second chamber 23, exhaust hole 24, sampling component 3, sampling tube 31, bellows 32, sampling port 33, air inlet 34, stirring component 4, fan blades 41, rotary joint 42, threaded sleeve 43, threaded tube 44. DETAILED DESCRIPTION

[0023] The following will clearly and completely describe the concept and technical effects of the present invention in combination with the embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention: Example: See also Figure 1 A gas sampling and analysis device includes a gas cylinder 1 and a recovery component 2 disposed in the gas cylinder 1. The recovery component 2 includes a piston 21, a pressure relief unit and a pressurizing unit. The piston 21 is slidably disposed on the inner wall of the gas cylinder 1. The piston 21 is used to separate the gas cylinder 1 into a first chamber 22 and a second chamber 23. The first chamber 22 is formed by the upper end of the piston 21 and the inside of the gas cylinder 1, and the second chamber 23 is formed by the lower end of the piston and the inside of the gas cylinder 1. In the initial state, the pressure of the second chamber 23 is greater than the pressure of the first chamber 22. The pressure relief unit and the pressurizing unit are used to relieve and pressurize the second chamber 23, respectively. The pressure relief unit includes an exhaust hole 24 and an exhaust valve, and the pressurization unit includes an intake hole 34 and an intake valve. The exhaust hole 24 and the intake hole 34 are symmetrically arranged on the bottle body at the bottom of the gas storage bottle 1, and the exhaust hole 24 and the intake hole 34 are both connected to the second chamber 23, the exhaust hole 24 is connected to the exhaust valve, and the intake hole 34 is connected to the intake valve. Both the intake valve and the exhaust valve are manual valves.

[0024] Specific working principle: The piston 21 divides the internal space of the gas cylinder 1 into a first chamber 22 and a second chamber 23, and stores the gas in the gas cylinder 1 in the first chamber 22. When the sample gas needs to be filled into the gas cylinder 1, the outlet end of the gas cylinder 1 is connected to the compressor through a pipeline, and the compressor is connected to the sample gas supply device through a pipeline (the compressor and the sample gas supply device are both existing technologies), and then the valve and the compressor at the outlet end of the gas cylinder 1 are opened in sequence to fill the external sample gas into the first chamber 22. After the sample gas is filled into the gas cylinder 1, it is necessary to turn off the compressor and disassemble the pipeline connected to the outlet end to facilitate the transportation and storage of the gas cylinder 1. After the compressor is turned off, the pipeline loses the high-pressure source. By opening the exhaust valve, the gas in the second chamber 23 is discharged to the outside of the second chamber 23 through the exhaust hole 24, thereby depressurizing the second chamber 23 and reducing the pressure of the second chamber 23, thereby increasing the volume of the first chamber 22 to generate negative pressure, and then sucking the sample gas remaining in the pipeline into the first chamber 22 to recover the gas remaining in the pipeline. Finally, the valve at the outlet of the gas storage bottle 1 is closed, and the pipes and other equipment connected to the outlet are disassembled, and the sample gas is stored in the gas storage bottle 1.

[0025] When sampling and analyzing the gas in the gas cylinder 1, the sampling device (this is the prior art) is connected to the valve at the outlet end of the gas cylinder 1 through a pipeline, and then the valve is opened to fill the air into the air inlet 34 through the air inlet valve, thereby increasing the volume of the second chamber 23 and reducing the volume of the first chamber 22. The gas in the first chamber 22 is filled into the sampling device from the outlet end under the push of the piston 21. After the gas is collected, the second chamber 23 is depressurized again through the pressure relief unit to recover the residual gas in the pipeline.

[0026] The sampling assembly 3 is also included. The sampling assembly 3 includes a sampling tube 31 and a bellows 32. One end of the bellows 32 is connected to the gas outlet end of the gas storage bottle 1. The free end of the bellows 32 is connected to the sampling tube 31. The free end of the sampling tube 31 is rotatably connected to the piston 21. The sampling tube 31 is provided with a plurality of sampling ports 33, including two sampling ports 33 arranged circumferentially along the axis of the sampling tube 31 and two sampling ports 33 arranged at intervals along the axis of the sampling tube 31. The sampling ports 33 arranged at intervals can correspond to gases of different densities respectively, and can perform layered sampling of gases of different densities, so that the sampling results are closer to the actual concentration of the standard mixed gas. It should be noted that the number of the sampling ports 33 arranged at intervals can be increased according to the gas components stored in the gas storage bottle 1. For example, when three gases of different densities are arranged in the gas storage bottle 1, the sampling ports 33 can be increased.

[0027] Specific working principle: when sampling, the second chamber 23 is pressurized by the booster unit, so that the piston 21 drives the sampling tube 31 to move, thereby compressing the bellows 32 and reducing the volume of the first chamber 23. The sample gas enters the sampling tube 31 and the bellows 32 from the sampling port 33 in turn, and finally is discharged from the gas outlet of the gas storage bottle 1. At the same time, the sampling ports 33 arranged at intervals correspond to the different density gases in the upper and lower layers, respectively, so as to sample the sample gas in layers, so that the sampling structure is closer to the actual concentration of the standard mixed gas.

[0028] The stirring assembly 4 also includes a fan blade 41 and a driving unit for driving the fan blade 41 to rotate. The fan blade 41 is arranged on the sampling tube 31. The end of the sampling tube 31 is rotatably connected to the upper end of the piston 21. The head end of the sampling tube 31 is rotatably connected to a rotary joint 42. The other end of the rotary head 42 is rotatably connected to the bellows 32. The driving unit includes a threaded sleeve 43 and a threaded tube 44. The threaded sleeve 44 is threadedly connected to the threaded tube 44. The threaded sleeve 43 is fixedly connected to the inner wall of the gas storage cylinder 1. The threaded tube 44 is fixedly arranged on the outer wall of the sampling tube 31. It should be noted that since the threaded tube 44 and the threaded sleeve 43 are matched by the up and down movement of the sampling tube 31, so that the sampling tube 31 rotates, the thread spacing of the threaded arrangement of the threaded tube 44 and the threaded sleeve 43 is large, so that the threaded tube 44 can be threadedly rotated when moving up and down.

[0029] Specific working principle: When sampling, the booster unit boosts the pressure of the second chamber 23, causing the piston 21 to push the sampling tube 31 toward the gas outlet end of the gas storage tank 1, so that the threaded tube 44 cooperates with the threaded sleeve 43, and the threaded tube 44 drives the fan blades on the sampling tube 31 to rotate, thereby stirring and mixing the stratified gas.

[0030] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A gas sampling and analysis device, comprising a gas storage cylinder (1), characterized in that: It also includes a recycling component (2), wherein the recycling component (2) includes: A piston (21), wherein the piston (21) is slidably disposed in the gas storage bottle (1); A first chamber (22), wherein the first chamber (22) is a first chamber (22) formed by the piston (21) and the gas storage bottle (1); a second chamber (23), the second chamber (23) being a second chamber (23) enclosed by the piston (21) and the gas storage bottle (1), the pressure of the second chamber (23) being greater than the pressure of the first chamber (22); A pressure relief unit, the pressure relief unit being used to relieve pressure in the second chamber (23); A pressurizing unit, wherein the pressurizing unit is used to pressurize the second chamber (23).

2. A gas sampling and analysis device according to claim 1, characterized in that: The pressure relief unit comprises an exhaust hole (24) and an exhaust valve, wherein the exhaust hole (24) is provided on the body of the gas storage bottle (1), the exhaust hole (24) is communicated with the second chamber (23), and the exhaust valve is communicated with the exhaust hole (24).

3. A gas sampling and analysis device according to claim 1, characterized in that: The device also comprises a sampling assembly (3), the sampling assembly (3) comprising a sampling tube (31) and a bellows (32), one end of the bellows (32) being in communication with the gas outlet end of the gas storage bottle (1), the free end of the bellows (32) being in communication with the sampling tube (31), the free end of the sampling tube (31) being connected to the piston (21), and the sampling tube (31) being provided with a sampling port (33).

4. A gas sampling and analysis device according to claim 3, characterized in that: There are a plurality of sampling ports (33), and the plurality of sampling ports (33) are arranged at intervals along the axis of the sampling tube (31).

5. A gas sampling and analysis device according to claim 3, characterized in that: The invention also comprises a stirring assembly (4), the stirring assembly (4) comprising a fan blade (41) and a driving unit for driving the fan blade (41) to rotate, the fan blade (41) being arranged on a sampling tube (31), the sampling tube (31) being rotationally connected to a piston (21), the sampling tube (31) being connected to a rotary joint (42), the other end of the rotary joint (42) being rotationally connected to a bellows (32).

6. A gas sampling and analysis device according to claim 5, characterized in that: The drive unit comprises a threaded sleeve (43) and a threaded tube (44); the threaded sleeve (43) is threadedly connected to the threaded tube (44); the threaded sleeve (43) is fixedly connected to the inner wall of the gas storage bottle (1); and the threaded tube (44) is fixedly arranged on the outer wall of the sampling tube (31).

7. A gas sampling and analysis device according to claim 3, characterized in that: The boosting unit comprises an air inlet hole (34) and an air inlet valve, wherein the air inlet hole (34) is arranged on the body of the gas storage bottle (1), the air inlet hole (34) is communicated with the second chamber (23), and the air inlet hole (34) is communicated with the air inlet valve.

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