Gas chromatograph for gas detection

Abstract

The utility model relates to a gas chromatograph for gas detection, and aims to solve the problems that the separation efficiency is low, the quantitative precision is not high, the stability of the instrument is influenced, the quantitative analysis precision is seriously influenced, and the quantitative analysis precision is influenced due to the problem of unstable gas flow in the use process of the conventional gas chromatograph. The device comprises an air inlet cylinder, an electric push rod is fixedly connected to the center of the bottom of the air inlet cylinder, the telescopic end of the electric push rod penetrates through the bottom of the air inlet cylinder and is fixedly connected with a push plate on the inner side of the air inlet cylinder, and the push plate is in sliding connection with the inner side of the air inlet cylinder. According to the utility model, gas is conveyed to the inner sides of the gas inlet cylinder and the centrifugal cylinder, and the push plate ascends at a constant speed to drive the internal gas to enter the chromatograph main body at a constant speed, so that the separation efficiency is obviously optimized, the quantitative precision is improved, the overall stability of the instrument is enhanced, and the analysis performance is further improved.

Description

Technical Field

[0001] This utility model relates to the field of gas chromatography technology, specifically a gas chromatograph for gas detection. Background Technology

[0002] In fields such as industrial production, environmental monitoring, public safety, and healthcare, the demand for precise detection of gas components is growing. For example, in chemical production, it is necessary to monitor the concentration of volatile organic compounds in real time to prevent explosion risks, while in the medical field, it is necessary to detect trace biomarkers in exhaled breath to assist in disease diagnosis. Gas chromatographs, with their high sensitivity, high resolution, and multi-component analysis capabilities, have become the core equipment for gas detection.

[0003] Traditional gas chromatographs suffer from unstable gas flow, leading to low separation efficiency, low quantitative accuracy, and compromised instrument stability, severely impacting the precision of quantitative analysis and consequently the accuracy of test results. To address this issue, a novel technical solution is proposed. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology, adapt to practical needs, and provide a gas chromatograph for gas detection. This invention addresses the problem of unstable gas flow in the use of traditional gas chromatographs, which leads to low separation efficiency, low quantitative accuracy, and affects the stability of the instrument, seriously impacting the accuracy of quantitative analysis and consequently the accuracy of the detection results.

[0005] To achieve the purpose of this utility model, the technical solution adopted by this utility model is as follows: a gas chromatograph for gas detection is designed, including an air inlet cylinder. An electric push rod is fixedly connected to the center of the bottom of the air inlet cylinder. The telescopic end of the electric push rod passes through the bottom of the air inlet cylinder and is fixedly connected to a push plate on the inner side of the air inlet cylinder. The push plate is slidably connected to the inner side of the air inlet cylinder. A sealing ring is fixedly connected to the outer wall of the air inlet cylinder, and the sealing ring is in contact with the inner wall of the air inlet cylinder.

[0006] In this scheme, by transporting the gas to the inside of the inlet cylinder and centrifuge cylinder, and having the pusher plate rise at a constant speed, the internal gas is driven into the chromatograph body at a constant speed, which significantly optimizes the separation efficiency, improves the quantitative accuracy, and enhances the overall stability of the instrument, thereby improving the analytical performance.

[0007] Preferably, a centrifuge cylinder is connected above the air inlet cylinder, a secondary cylinder is connected above the centrifuge cylinder, the secondary cylinder and the filter cylinder are connected to each other through a gas supply pipe, and the filter cylinder is connected to the air inlet of the chromatograph body through a pipe section.

[0008] In practical applications, the secondary cylinder facilitates the screw's ascent and also allows for the storage of more sample gas, thus improving detection efficiency and accuracy.

[0009] Preferably, a centrifugal disc is rotatably connected to the inner side of the centrifugal cylinder, a threaded sleeve is fixedly connected to the center of the centrifugal disc, and several centrifugal blades are fixedly connected in a circumferential array on the outer side wall of the threaded sleeve.

[0010] In practical applications, the screw moves upward with the push plate, and when it passes through the threaded sleeve, it drives the threaded sleeve and the centrifugal disc to rotate. The inner side of the centrifugal disc is divided into several spiral channels by the centrifugal blades, and the centrifugal force field is used to mechanically pre-separate some aerosol particles in the gas.

[0011] Preferably, a screw is fixedly connected to the top of the push plate, and the screw passes through the threaded sleeve and is threadedly connected to the threaded sleeve.

[0012] In practical applications, the screw drives the threaded sleeve to rotate, and there is a gap between the threaded sleeve and the screw. The surface of the screw is coated with lubricating material to ensure that it will not get stuck when driving the threaded sleeve to rotate.

[0013] Preferably, two positioning strips are fixedly connected to the inner side wall of the air intake cylinder, and a positioning groove is provided on the outer side wall of the push plate. The positioning strips pass through the positioning groove and are slidably connected to the positioning groove.

[0014] In practical applications, the constraint of the positioning strip can keep the push plate stable during the lifting and lowering process, preventing it from shaking or tilting. On the one hand, it avoids the electric push rod being subjected to lateral forces, and on the other hand, it can maintain the sealing effect of the sealing ring.

[0015] Preferably, an air inlet pipe is fixedly connected to the side wall of the air inlet cylinder, the air inlet pipe communicates with the air inlet cylinder, a first-way valve is sealed to the surface of the air inlet pipe, a connector is fixedly connected to the outer end of the air inlet pipe, and a second-way valve is sealed to the surface of the air delivery pipe above the auxiliary cylinder.

[0016] In practical applications, the No. 1 and No. 2 one-way valves can store sample gas for a period of time. When the push plate is not raised, the gas pressure is insufficient, so the No. 2 one-way valve is still closed. When the push plate pushes the sample gas, the gas pressure increases, and the sample gas opens the No. 2 one-way valve, at which point a uniform gas intake operation begins.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] 1. This utility model significantly optimizes separation efficiency, improves quantitative accuracy, and enhances the overall stability of the instrument by transporting gas to the inside of the air inlet cylinder and centrifuge cylinder, and by having the pusher plate rise at a uniform speed to drive the internal gas into the chromatograph body at a uniform speed. This also improves analytical performance.

[0019] 2. This utility model, by setting up a centrifugal disc, allows the screw on its surface to move upwards as the pusher plate pushes the gas in at a uniform speed. When the screw passes through the threaded sleeve, it drives the threaded sleeve and the centrifugal disc to rotate. The inner side of the centrifugal disc is divided into several spiral channels by centrifugal blades. The centrifugal force field is used to mechanically pre-separate some aerosol particles in the gas, effectively reducing the possibility of particulate matter entering the chromatographic column, providing convenience for subsequent filtration and purification steps, and further improving the accuracy and reliability of detection. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0021] Figure 2 This is a schematic cross-sectional view of the air intake assembly of this utility model;

[0022] Figure 3 This is a schematic diagram of the push plate structure of this utility model;

[0023] Figure 4 This is a schematic diagram of the inner structure of the centrifuge disc of this utility model;

[0024] In the diagram: 1. Chromatograph body; 2. Inlet cylinder; 201. Positioning strip; 3. Push plate; 301. Positioning groove; 302. Sealing ring; 4. Electric actuator; 5. Screw; 6. Centrifuge cylinder; 7. Centrifuge disc; 701. Threaded sleeve; 702. Centrifuge blades; 8. Inlet pipe; 801. First check valve; 802. Connector; 9. Secondary cylinder; 10. Second check valve; 11. Gas delivery pipe; 12. Filter cylinder. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0026] Example 1: A gas chromatograph for gas detection, see [link to example]. Figures 1 to 4The system includes an air inlet cylinder 2, with an electric actuator 4 fixedly connected to the center of its bottom. The telescopic end of the electric actuator 4 passes through the bottom of the air inlet cylinder 2 and is fixedly connected to a push plate 3 on the inner side of the air inlet cylinder 2. The push plate 3 is slidably connected to the inner side of the air inlet cylinder 2. In use, the sample gas is poured into the air inlet cylinder 2, and then the electric actuator 4 is activated, causing the push plate 3 to rise at a constant speed. As the push plate 3 moves, it pushes the sample gas upward, eventually entering the chromatograph body 1. Stable airflow conditions optimize separation efficiency, quantitative accuracy, and instrument stability, thereby improving analytical performance. A sealing ring 302 is fixedly connected to the outer wall of the air inlet cylinder 2, and the sealing ring 302 is attached to the inner wall of the air inlet cylinder 2. The sealing ring 302 prevents gas from leaking out from the gap between the push plate 3 and the air inlet cylinder 2, which would result in insufficient pushing air pressure and affect the uniformity of air intake. Two positioning strips 201 are fixedly connected to the inner wall of the air inlet cylinder 2, and a positioning groove 301 is opened on the outer wall of the push plate 3. The positioning strips 201 pass through the positioning groove 301 and slide in connection with the positioning groove 301. The positioning strips 201 make the lifting process of the push plate 3 more stable and prevent problems such as tilting of the push plate 3. It should also be noted that the positioning groove 301 of the push plate 3 is also covered with a sealing ring 302 to ensure the sealing effect. The sealing ring 302 needs to be inspected and replaced regularly to ensure its sealing performance.

[0027] For details, see Figure 2 and Figure 3 As shown, a centrifugal disc 7 is rotatably connected to the inner side of the centrifugal cylinder 6. A threaded sleeve 701 is fixedly connected to the center of the centrifugal disc 7. Several centrifugal blades 702 are fixedly connected in a circular array on the outer side wall of the threaded sleeve 701. A screw 5 is fixedly connected to the top of the push plate 3. The screw 5 passes through the threaded sleeve 701 and is threadedly connected to the threaded sleeve 701. The centrifugal disc 7 has the ability to rotate freely. When the push plate 3 pushes the gas to enter at a uniform speed, the screw 5 on its surface will move upward. When it passes through the threaded sleeve 701, it drives the threaded sleeve 701 and the centrifugal disc 7 to rotate. The inner side of the centrifugal disc 7 is divided into several spiral channels by the centrifugal blades 702. The centrifugal force field is used to mechanically pre-separate some aerosol particles in the gas, which is convenient for subsequent filtration and purification.

[0028] Furthermore, such as Figure 1 As shown, a centrifuge cylinder 6 is connected above the air inlet cylinder 2, and a secondary cylinder 9 is connected above the centrifuge cylinder 6. The main function of the secondary cylinder 9 is to provide storage space for the screw 5 after it rises. The secondary cylinder 9 and the filter cylinder 12 are connected to each other through a gas supply pipe 11. The filter cylinder 12 is connected to the air inlet of the chromatograph body 1 through a pipe. The gas passing through the secondary cylinder 9 will pass through the gas supply pipe 11 and enter the filter cylinder 12. After being filtered by the filter cylinder 12, it finally enters the chromatograph body 1 for detection. The filtered gas can avoid the interference of impurities on the detection, thus improving the detection efficiency.

[0029] It is worth mentioning that the filter cartridge 12 can be equipped with particulate filter materials such as glass fiber filter membranes, stainless steel sintered filter elements, or porous ceramic filter elements to intercept solid particles (such as dust and metal fragments). At the same time, adsorbents such as 5A molecular sieves, activated carbon, or silica gel can be added to adsorb impurities such as moisture, hydrocarbons, or oxygen in the carrier gas. Chemical filtration components such as reduced copper powder, activated alumina loaded with metal, or zinc oxide can be used to specifically remove harmful gases such as oxygen, halides, or sulfides. Alternatively, a composite filter layer can be formed by combining particulate filter materials with adsorbents / chemical filtration components to achieve the function of simultaneously removing particulate matter and gaseous impurities. The filter cartridge 12 can protect the chromatographic column from stationary phase loss or column efficiency reduction caused by particulate matter and moisture contamination, prevent the detector from generating baseline noise, signal drift, or even component damage due to impurity accumulation, and avoid interference from particulate matter or gaseous impurities in the sample with the separation and detection of target components, thereby improving the accuracy and repeatability of analytical results.

[0030] It is worth noting that, such as Figure 2 As shown, an air inlet pipe 8 is fixedly connected to the side wall of the air inlet cylinder 2. The air inlet pipe 8 is connected to the air inlet cylinder 2. A first-way valve 801 is sealed to the surface of the air inlet pipe 8. A connector 802 is fixedly connected to the outer end of the air inlet pipe 8. A second-way valve 10 is sealed to the surface of the gas delivery pipe 11 above the auxiliary cylinder 9. The length of the air inlet pipe 8 can be determined according to the actual situation and is not a fixed value. The connector 802 can be easily connected to the sample container, such as a gas cylinder or pressure vessel, or to some gas priming equipment, such as a blower. The first-way valve 801 and the second-way valve 10 can first intercept most of the sample gas inside the air inlet cylinder 2 and the auxiliary cylinder 9, waiting for the electric push rod 4 and the push plate 3 to move, and then start the gas intake and detection operation, thereby avoiding unevenness when the sample gas enters.

[0031] It's worth noting that the working principle of a gas chromatograph is based on the difference in interaction between substances in the mobile gas (carrier gas) and the stationary phase (chromatographic column) to achieve the separation of mixtures. Its core component, the chromatographic column, is filled with a special adsorbent material. When a gaseous sample passes through the column under the carrier gas, different components migrate at different speeds due to their different adsorption capacities on the stationary phase, thus achieving separation. Specifically, the gas chromatograph injects the sample into the column. The stationary phase inside the column has different adsorption or dissolution capacities for different components, causing each component to repeatedly partition between the mobile and stationary phases. Due to differences in partition coefficients, different elution times are achieved, completing the physical separation. The separated components enter the detector and are converted into electrical signals. The data processing system analyzes these signals to obtain information such as the concentration, purity, and relative content of each component.

[0032] First, check the instrument's condition to ensure it is level and all components are in good working order. Turn on the gas source and adjust the total and split flow rates. Set the column temperature, inlet temperature, and detector temperature. Turn on the detector and set the sensitivity and output signal attenuation. Next, prepare or collect the sample gas. Push the sample into the chromatographic column at a uniform speed using pusher plate 3. Once the parameters reach the set values, begin analysis and obtain the results. After the experiment, purge the column with nitrogen and then turn off the instrument. Since this invention focuses on improving and designing the gas inlet, no improvements have been made to the internal structure and working principle of the chromatograph. These are not technical solutions that require protection under this invention and will not be described further.

[0033] In addition, all components designed in this utility model are general standard parts or components known to those skilled in the art. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods. Those skilled in the art can fully implement them, so there is no need to elaborate. The content protected by this utility model does not involve improvements to the internal structure and method.

[0034] The embodiments disclosed herein are preferred embodiments, but are not limited thereto. Those skilled in the art can readily grasp the spirit of this utility model based on the above embodiments and make different extensions and variations. However, as long as they do not depart from the spirit of this utility model, they are all within the protection scope of this utility model.

Claims

1. A gas chromatograph for gas detection, comprising an inlet cylinder (2), characterized in that, An electric push rod (4) is fixedly connected to the center of the bottom of the air inlet cylinder (2). The telescopic end of the electric push rod (4) passes through the bottom of the air inlet cylinder (2) and is fixedly connected to the push plate (3) on the inner side of the air inlet cylinder (2). The push plate (3) is slidably connected to the inner side of the air inlet cylinder (2). A sealing ring (302) is fixedly connected to the outer wall of the air inlet cylinder (2). The sealing ring (302) fits against the inner wall of the air inlet cylinder (2).

2. The gas chromatograph for gas detection as described in claim 1, characterized in that, The upper part of the air inlet cylinder (2) is connected to the centrifuge cylinder (6), and the upper part of the centrifuge cylinder (6) is connected to the auxiliary cylinder (9). The auxiliary cylinder (9) and the filter cylinder (12) are connected to each other through the gas supply pipe (11). The filter cylinder (12) is connected to the air inlet of the chromatograph body (1) through a pipe.

3. A gas chromatograph for gas detection as described in claim 2, characterized in that, The centrifuge cylinder (6) is rotatably connected to a centrifuge disc (7), and a threaded sleeve (701) is fixedly connected to the center of the centrifuge disc (7). Several centrifuge blades (702) are fixedly connected to the outer side wall of the threaded sleeve (701) in a circumferential array.

4. A gas chromatograph for gas detection as described in claim 3, characterized in that, The top end of the push plate (3) is fixedly connected to a screw (5), which passes through the threaded sleeve (701) and is threadedly connected to the threaded sleeve (701).

5. A gas chromatograph for gas detection as described in claim 1, characterized in that, The inner wall of the air inlet cylinder (2) is fixedly connected with two positioning strips (201), and the outer wall of the push plate (3) is provided with a positioning groove (301). The positioning strips (201) pass through the positioning groove (301) and are slidably connected to the positioning groove (301).

6. A gas chromatograph for gas detection as described in claim 2, characterized in that, An air inlet pipe (8) is fixedly connected to the side wall of the air inlet cylinder (2). The air inlet pipe (8) is connected to the air inlet cylinder (2). A first-way valve (801) is sealed to the surface of the air inlet pipe (8). A connector (802) is fixedly connected to the outer end of the air inlet pipe (8). A second-way valve (10) is sealed to the surface of the air supply pipe (11) above the auxiliary cylinder (9).

Images