CN108982173A - Gas sampling analysis system and its method - Google Patents

Abstract

The invention discloses a gas sampling analysis system and a method thereof. The system comprises a sample gas tank, a nitrogen tank, a piston sample storage device, a vacuum pump and a gas analyzer. The gas outlets of the sample gas tank and the nitrogen gas tank are connected to the piston storage The gas inlet of the sampler is connected, and the gas outlet of the piston sample holder is connected with the gas inlet of the vacuum pump and the gas analyzer respectively. The piston sample holder includes a gas storage tank and a piston that is arranged inside the gas storage tank to slide and fit with it. One end of the gas storage tank is provided with a flange fixedly connected to it, and the other end of the gas storage tank is pierced with a ring fixed to the piston. A connected push rod; the push rod is provided with a support seat fixedly connected with it. The gas sampling and analysis system of the present invention can not only sample high-temperature gas sources, low-temperature gas sources, high-pressure gas sources and low-pressure gas sources, but also perform real-time analysis on the collected gas components, thereby improving the accuracy of experimental data.

Description

Gas sampling analysis system and method thereof

technical field

The invention relates to the technical field of gas sampling and analysis, in particular to a gas sampling and analysis system and a method thereof.

Background technique

At present, gas sampling devices are widely used in petroleum, chemical, pharmaceutical and other industries. According to the different pressures applicable to gas sampling devices, they can be divided into high-pressure sampling and low-pressure sampling. Gas sampling devices with an operating pressure higher than 0.1MPa are high-pressure systems Sampling device, and vice versa for low-pressure system sampling device. According to whether the structure of the gas sampling device is airtight, it can be divided into airtight and non-hermetic sampling devices. Although the structure of the non-hermetic gas sampling device is simple, the airtightness is poor, resulting in sample loss and leakage during measurement.

Most of the existing gas sampling systems or devices are designed and processed for specific gas sources or equipment, which cannot take into account the gas sampling under two different conditions of low pressure and high pressure, and also cannot insulate the high temperature gas source, making the gas The composition of the source is greatly affected, resulting in certain deviations in the measurement and analysis. In addition, the structure of the existing gas sampling device is too complex, the operation is very cumbersome, and it is not easy for practical application.

Contents of the invention

The purpose of the present invention is to provide a gas sampling and analysis system and method thereof, which can sample high-temperature gas sources, low-temperature gas sources, high-pressure gas sources and low-pressure gas sources, and solve the current problem of sampling high-temperature and low-pressure gas sources. At the same time, real-time analysis and processing of gas source components can be performed to reduce errors in the measurement and analysis process and improve the accuracy of detection results.

In order to achieve the above object, the gas sampling and analysis system designed by the present invention includes a sample gas tank, a nitrogen gas tank, a piston sample holder, a vacuum pump and a gas analyzer, and the gas outlets of the sample gas tank and the nitrogen gas tank are connected to the piston for storing samples. connected to the air inlet of the device, and the gas outlet of the piston sample holder is connected to the air inlet of the vacuum pump and the gas analyzer respectively;

The piston sample holder includes a gas storage tank and a piston that is arranged inside the gas storage tank to slide and cooperate with it. A connected push rod; the push rod is provided with a support seat fixedly connected with it.

Further, the gas outlet of the sample gas tank is provided with a first pipeline, the gas outlet of the nitrogen tank is provided with a second pipeline, and the gas inlet of the piston sampler is provided with a third pipe The first pipeline, the second pipeline and the third pipeline communicate with each other through a first three-way valve; the first pipeline is provided with a first valve, and the second pipeline is provided with a second a valve, a third valve is arranged on the third pipeline;

The air inlet of the vacuum pump is provided with a fourth pipeline, the air inlet of the gas analyzer is provided with a fifth pipeline, and the gas outlet of the piston sampler is provided with a sixth pipeline, so The fourth pipeline, the fifth pipeline, and the sixth pipeline are connected through the second three-way valve; the fourth pipeline is provided with a fourth valve, and the fifth pipeline is provided with a fifth valve.

Further, the bottom of the support seat is provided with a slider fixedly connected thereto, and a slide rail is provided below the slide block for sliding cooperation with it, and the support seat can drive the slider to slide along the slide rail under the action of an external force.

Further, the slider is provided with a manual lock for limiting the slider.

Further, the outer ring of the piston is provided with a first sealing ring for sealing with the inner wall of the air storage cylinder.

Further, a sealing groove is provided on the side where the flange plate and the air storage cylinder are bonded, and a second sealing ring for sealing the bonding surface of the flange plate and the gas storage cylinder is provided in the sealing groove.

Further, the bottom of the gas storage tank is provided with a mounting seat fixedly connected thereto; the outer wall of the gas storage tank is covered with a heating insulation cover, and the heating insulation cover is provided with a temperature controller for controlling its temperature.

Still further, the piston sample reservoir is provided with a pressure gauge for monitoring the inner chamber pressure.

Furthermore, the flange is provided with a first interface for connecting with the third pipeline, a second interface for connecting with the sixth pipeline, and a third interface for connecting with the pressure gauge; The flange plate and the air storage tank are fixedly connected by bolts.

The present invention also provides a method for sampling and analyzing using the above-mentioned gas sampling and analyzing system, comprising the following steps:

1) Empty exhaust gas:

Close the first valve, the second valve, and the fifth valve, open the third valve and the fourth valve, start the vacuum pump to empty the waste gas in the air storage tank, the pressure in the air storage tank decreases, and drive the piston to compress the air storage tank until the gas in the chamber The volume is the smallest, and the vacuum pump is turned off after the exhaust gas is evacuated;

2) Nitrogen filling:

Open the nitrogen tank and the second valve to fill the nitrogen into the gas storage tank, the pressure in the gas storage tank increases, the driving piston and the push rod move in reverse to the set position, and then lock the slider manually, and close the second valve after the nitrogen gas is filled. valve;

3) Nitrogen pumping:

Start the vacuum pump, pump out the nitrogen in the gas storage tank, and repeat step 2) and step 3) for 2 to 5 times. After the last nitrogen pumping, close the second valve;

4) Inlet gas:

Open the first valve, start the vacuum pump to pump the sample gas in the sample gas tank into the gas storage tank through the first pipeline and the third pipeline in turn, and then flow out from the gas storage tank through the sixth pipeline and the fourth pipeline to the vacuum pump to be discharged. After setting the time, close the fourth valve and the vacuum pump, and store the sample gas in the gas storage tank;

5) Sampling analysis:

Open the fifth valve, and send the sample gas stored in the gas storage cylinder to the gas analyzer for sampling and analysis by pushing the push rod, that is, the sampling and analysis is completed.

Compared with the prior art, the present invention has the advantages of:

First, the gas sampling and analysis system of the present invention is designed with a sample gas tank, a nitrogen tank, a piston sample holder, a vacuum pump and a gas analyzer, which can not only sample high-temperature gas sources, low-temperature gas sources, high-pressure gas sources and low-pressure gas sources , to solve the current problem of difficult sampling of high-temperature and low-pressure gas sources, and at the same time, real-time analysis and processing of gas source components can be performed to reduce errors in the measurement and analysis process and improve the accuracy of detection results.

Its two, the piston sample holder of the present invention is designed with air storage tank, piston and push rod, wherein the outer wall cover of air storage tank is provided with heating insulation cover, is provided with the temperature controller that is used for it temperature control on the heating insulation cover, can Insulation treatment is carried out on the high-temperature gas source to prevent the composition of the gas source from being affected by the temperature difference, reduce the deviation in the measurement and analysis, and improve the accuracy of the test.

Third, the outer ring of the piston designed in the present invention is provided with a first sealing ring for sealing with the inner wall of the air storage cylinder, and a sealing groove is provided on the side where the flange plate and the air storage cylinder fit together, and a sealing groove for sealing the flange plate is arranged in the sealing groove. The second sealing ring on the surface of the gas storage cylinder is conducive to enhancing the sealing of the gas in the gas storage cylinder and avoiding the loss and leakage of samples during gas measurement.

Description of drawings

Fig. 1 is the structural representation of a kind of gas sampling analysis system;

Fig. 2 is a side view structural schematic diagram of the flange in Fig. 1;

In the figure, sample gas tank 1, nitrogen tank 2, piston sample holder 3, gas storage tank 3.1, piston 3.2, flange plate 3.3, first interface 3.31, second interface 3.32, third interface 3.33, push rod 3.4, support Seat 3.5, slider 3.6, slide rail 3.7, manual lock 3.8, sealing groove 3.9, mounting seat 3.10, vacuum pump 4 and gas analyzer 5, first pipeline 6.1, second pipeline 6.2, third pipeline 6.3, the first Four pipelines 6.4, fifth pipelines 6.5, sixth pipelines 6.6, first valve 7.1, second valve 7.2, third valve 7.3, fourth valve 7.4, fifth valve 7.5, first three-way valve 8.1, third valve Two and three-way valve 8.2, first sealing ring 9.1, second sealing ring 9.2, heating insulation cover 10, temperature controller 11, pressure gauge 12, bolt 13.

Detailed ways

Below in conjunction with specific embodiment the present invention is described in further detail:

A gas sampling and analysis system as shown in the figure includes a sample gas tank 1, a nitrogen gas tank 2, a piston sample holder 3, a vacuum pump 4, and a gas analyzer 5. The engine exhaust gas and exhaust gas reformed gas can be stored in the sample gas tank 1 or other equipment emissions. The gas outlets of the sample gas tank 1 and the nitrogen tank 2 are both connected to the air inlet of the piston sample holder 3, and the gas outlet of the piston sample holder 3 is connected to the air inlets of the vacuum pump 4 and the gas analyzer 5 respectively.

In the above-mentioned technical solution, the piston sample holder 3 includes an air storage cylinder 3.1 and a piston 3.2 which is arranged in the inside of the air storage cylinder 3.1 to slide and cooperate with it. There is a push rod 3.4 fixedly connected with the piston 3.2; the push rod 3.4 is provided with a support seat 3.5 fixedly connected with it, and the rod part of the push rod 3.4 adopts a thread structure, and its thread size is M10, and the length is 200-240mm. The flange 3.3 is fixedly connected with the air storage tank 3.1 by bolts 13, and the flange 3.3 is provided with eight φ6 through holes for installing the bolts 13.

In the above technical solution, the support seat 3.5 adopts a T-shaped structure, the bottom of the support seat 3.5 is provided with a slider 3.6 fixedly connected thereto, and the support seat 3.5 and the slider 3.6 are connected by bolts. The slide rail 3.7 slidingly matched with it is provided below the slide block 3.6, and the support seat 3.5 can drive the slide block 3.6 to slide along the slide rail 3.7 under the action of an external force. The slide block 3.6 is provided with a manual lock 3.8 which is used to limit the slide block 3.6. By rotating the manual lock 3.8, the slide block inside the manual lock and the slide rail are resisted to achieve the purpose of fixing the position limit.

In the above technical solution, the outer ring of the piston 3.2 is provided with a first sealing ring 9.1 for sealing with the inner wall of the air storage cylinder 3.1, and a sealing groove 3.9 is provided on the side of the flange plate 3.3 and the air storage cylinder 3.1, and a seal groove 3.9 is provided in the sealing groove 3.9. There is a second sealing ring 9.2 for sealing the bonding surface of the flange 3.3 and the gas storage cylinder 3.1, which is beneficial to enhance the airtightness of the gas in the gas storage cylinder and avoid sample loss and leakage during gas measurement. The bottom of the gas storage tank 3.1 is provided with a mounting seat 3.10 fixedly connected thereto; the outer wall of the gas storage tank 3.1 is provided with a heating insulation cover 10, and the heating insulation cover 10 is provided with a temperature controller 11 for temperature control thereof, and the piston stores samples. The device 3 is also provided with a pressure gauge 12 for monitoring the inner cavity pressure, and the pressure gauge 12 adopts a digital pressure gauge. In this way, the high-temperature gas source can be insulated by heating the heat-insulation jacket 10 to prevent the components of the gas source from being affected by the temperature difference, reduce the deviation in measurement and analysis, and improve the accuracy of the test.

In the above technical solution, the gas outlet of the sample gas tank 1 is provided with a first pipeline 6.1, the gas outlet of the nitrogen tank 2 is provided with a second pipeline 6.2, and the gas inlet of the piston sample holder 3 is provided with a third pipeline. The pipeline 6.3, the first pipeline 6.1, the second pipeline 6.2 and the third pipeline 6.3 are communicated through the first three-way valve 8.1; the first pipeline 6.1 is provided with a first valve 7.1, and the second pipeline 6.2 The second valve 7.2 is set on the upper part, and the third valve 7.3 is set on the third pipeline 6.3;

The air inlet of the vacuum pump 4 is provided with a fourth pipeline 6.4, the air inlet of the gas analyzer 5 is provided with a fifth pipeline 6.5, the gas outlet of the piston sampler 3 is provided with a sixth pipeline 6.6, and the gas outlet of the gas analyzer 5 is provided with a sixth pipeline 6.6. The fourth pipeline 6.4, the fifth pipeline 6.5, and the sixth pipeline 6.6 are connected through the second three-way valve 8.2; the fourth pipeline 6.4 is provided with a fourth valve 7.4, and the fifth pipeline 6.5 is provided with a fifth valve. Valve 7.5. The flange 3.3 is provided with a first interface 3.31 for connecting with the third pipeline 6.3, a second interface 3.32 for connecting with the sixth pipeline 6.6, and a third interface 3.33 for connecting with the pressure gauge 12.

A method for sampling and analyzing using the above-mentioned gas sampling and analyzing system, comprising the steps of:

1) Empty exhaust gas:

Close the first valve 7.1, the second valve 7.2, and the fifth valve 7.5, open the third valve 7.3, and the fourth valve 7.4, start the vacuum pump 4 to empty the waste gas in the air storage tank 3.1, the pressure in the air storage tank 3.1 decreases, and the piston is driven 3.2 Compress the air storage tank 3.1 until the gas volume in the cavity is minimum, and turn off the vacuum pump 4 after the exhaust gas is emptied;

2) Nitrogen filling:

Open the nitrogen tank 2 and the second valve 7.2 to fill the nitrogen into the gas storage tank 3.1, the pressure in the gas storage tank 3.1 increases, the driving piston 3.2 and the push rod 3.4 move in reverse to the set position, and then lock the slider 3.6 through the manual lock 3.8 , close the second valve 7.2 after filling the nitrogen;

3) Nitrogen pumping:

Start the vacuum pump 4, pump out the nitrogen in the gas storage tank 3.1, and repeat steps 2 and 3 for 2 to 5 times, and close the second valve 7.2 after the last nitrogen pumping;

4) Inlet gas:

Open the first valve 7.1, start the vacuum pump 4 to pump the sample gas in the sample gas tank 1 into the gas storage tank 3.1 through the first pipeline 6.1, the third pipeline 6.3, and then flow out from the gas storage tank 3.1 through the sixth pipeline 6.6, the first pipeline The fourth pipeline 6.4 is discharged to the vacuum pump 4, and after the set time, the fourth valve 7.4 and the vacuum pump 4 are closed to store the sample gas in the gas storage tank 3.1;

5) Sampling analysis:

The fifth valve 7.5 is opened, and the sample gas stored in the gas storage tank 3.1 is sent to the gas analyzer 5 for sampling and analysis by pushing the push rod 3.4, that is, the sampling and analysis is completed.

The invention can not only sample high-temperature gas source, low-temperature gas source, high-pressure gas source and low-pressure gas source, but also conduct real-time analysis on the collected gas components, and apply it to the measurement and analysis of internal combustion engine tail gas, atmosphere, combustible gas and chemical tail gas , greatly improving the accuracy of the experimental data.

The above is only a specific embodiment of the present invention, and it should be pointed out that the rest of the content that is not described in detail is the prior art, and any changes or replacements that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention are all Should be covered within the protection scope of the present invention.

Claims (10)

1. A gas sampling analysis system, characterized in that: comprising a sample gas tank (1), a nitrogen tank (2), a piston sampler (3), a vacuum pump (4) and a gas analyzer (5), the sample The gas outlets of the gas tank (1) and the nitrogen tank (2) are all connected to the air inlet of the piston sample holder (3), and the gas outlet of the piston sample holder (3) is respectively connected to the vacuum pump (4), the gas analyzer The air inlet of instrument (5) is connected; The piston sample holder (3) includes an air storage cylinder (3.1) and a piston (3.2) which is arranged inside the air storage cylinder (3.1) to slide and fit with it, and one end of the air storage cylinder (3.1) is provided with a flange fixedly connected to it disc (3.3), the other end of the air storage tank (3.1) is pierced with a push rod (3.4) fixedly connected with the piston (3.2); the push rod (3.4) is provided with a support seat (3.5) fixedly connected with it ). 2. The gas sampling analysis system according to claim 1, characterized in that: the gas outlet of the sample gas tank (1) is provided with a first pipeline (6.1), and the gas outlet of the nitrogen tank (2) A second pipeline (6.2) is provided at the place, a third pipeline (6.3) is provided at the air inlet of the piston sample accumulator (3), the first pipeline (6.1), the second pipeline ( 6.2) and the third pipeline (6.3) are communicated through the first three-way valve (8.1); the first pipeline (6.1) is provided with a first valve (7.1), and the second pipeline (6.2 ) is provided with a second valve (7.2), and the third pipeline (6.3) is provided with a third valve (7.3); The air inlet of the vacuum pump (4) is provided with a fourth pipeline (6.4), the air inlet of the gas analyzer (5) is provided with a fifth pipeline (6.5), and the piston sample reservoir (3) A sixth pipeline (6.6) is provided at the gas outlet, and the fourth pipeline (6.4), the fifth pipeline (6.5), and the sixth pipeline (6.6) pass through the second three-way valve (8.2) connected; the fourth pipeline (6.4) is provided with a fourth valve (7.4), and the fifth pipeline (6.5) is provided with a fifth valve (7.5). 3. The gas sampling and analysis system according to claim 2, characterized in that: the bottom of the support base (3.5) is provided with a slider (3.6) fixedly connected to it, and the bottom of the slider (3.6) is provided with a With the matched slide rail (3.7), the support seat (3.5) can drive the slide block (3.6) to slide along the slide rail (3.7) under the action of external force. 4. The gas sampling and analysis system according to claim 3, characterized in that: the slider (3.6) is provided with a manual lock (3.8) for limiting the slider (3.6). 5. The gas sampling and analysis system according to claim 4, characterized in that: the outer ring of the piston (3.2) is provided with a first sealing ring (9.1) for sealing with the inner wall of the gas storage cylinder (3.1). 6. The gas sampling and analysis system according to claim 5, characterized in that: a sealing groove (3.9) is provided on the side of the flange (3.3) and the gas storage cylinder (3.1), and the sealing groove ( 3.9) is provided with a second sealing ring (9.2) for sealing the joint surface of the flange (3.3) and the air storage tank (3.1). 7. The gas sampling and analysis system according to claims 2-6, characterized in that: the bottom of the gas storage tank (3.1) is provided with a mounting seat (3.10) fixedly connected thereto; the outer wall of the gas storage tank (3.1) The cover is provided with a heating insulation cover (10), and the heating insulation cover (10) is provided with a temperature controller (11) for controlling its temperature. 8. The gas sampling and analysis system according to claim 7, characterized in that: the piston sample reservoir (3) is provided with a pressure gauge (12) for monitoring the pressure in its inner cavity. 9. The gas sampling analysis system according to claim 8, characterized in that: the flange (3.3) is provided with a first interface (3.31) for connecting with the third pipeline (6.3), for connecting with The second interface (3.32) connected to the sixth pipeline (6.6) and the third interface (3.33) used to connect with the pressure gauge (12); between the flange (3.3) and the air storage tank (3.1) Secure the connection with bolts (13). 10. A method utilizing the gas sampling analysis system according to claim 1 to carry out sampling analysis, characterized in that: comprising the steps of: 1) Empty exhaust gas: Close the first valve (7.1), the second valve (7.2), the fifth valve (7.5), open the third valve (7.3), the fourth valve (7.4), start the vacuum pump (4) to move the The waste gas is evacuated, the pressure in the gas storage tank (3.1) decreases, and the piston (3.2) is driven to compress the gas storage tank (3.1) until the gas volume in the cavity is minimum, and the vacuum pump (4) is turned off after the waste gas is evacuated; 2) Nitrogen filling: Open the nitrogen tank (2) and the second valve (7.2) to fill the nitrogen into the gas storage tank (3.1), the pressure in the gas storage tank (3.1) increases, and the driving piston (3.2) and push rod (3.4) move in reverse to the setting position, close the second valve (7.2) after filling the nitrogen; 3) Nitrogen pumping: Start the vacuum pump (4), pump out the nitrogen in the gas storage tank (3.1), and repeat step 2) and step 3) 2 to 5 times, and close the second valve (7.2) after the last nitrogen pumping; 4) Inlet gas: Open the first valve (7.1), start the vacuum pump (4) to draw the sample gas in the sample gas tank (1) through the first pipeline (6.1), the third pipeline (6.3) into the gas storage tank (3.1), and then The air storage tank (3.1) flows out through the sixth pipeline (6.6) and the fourth pipeline (6.4) to the vacuum pump (4), and after the set time, the fourth valve (7.4) and the vacuum pump (4) are closed, and the sample The gas is stored in the gas storage tank (3.1); 5) Sampling analysis: Open the fifth valve (7.5), and send the sample gas stored in the gas storage tank (3.1) to the gas analyzer (5) for sampling and analysis by pushing the push rod (3.4), that is, the sampling and analysis is completed.