Integrated automatic gas chromatograph

Abstract

The utility model provides an integrated automatic gas chromatograph and relates to the technical field of separation and analysis instruments. Comprising a shell and a main body structure arranged in the shell, and the main body structure comprises a sample feeding module, a reaction module, a gas feeding module, an analysis module and a control module; the sample feeding module comprises a multi-way valve, and the multi-way valve is provided with a carrier gas inlet, a to-be-detected gas inlet and a sample gas outlet communicated with the reaction module; the reaction module comprises a reaction chamber and a flame ionization detector which are sequentially arranged along the flow direction of the sample gas; an inlet of the reaction chamber is communicated with a sample gas outlet of the multi-way valve, an outlet of the reaction chamber is communicated with the flame ionization detector, and a chromatographic column is arranged in the reaction chamber; the analysis module comprises a gas analysis unit; and the gas analysis unit is electrically connected with the flame ionization detector through a signal line. On the basis, the gas chromatograph solves the problem that the existing gas chromatograph has defects in the aspects of integrated layout of internal core components and automation control collaboration.

Description

Technical Field

[0001] This utility model relates to the field of separation and analysis instrument technology, specifically to an integrated automated gas chromatograph. Background Technology

[0002] Gas chromatographs are analytical instruments used to separate and detect components in a gas mixture. They are widely used in environmental monitoring, industrial safety, food safety, and biomedicine. Traditional laboratory gas chromatographs, limited by their design concepts and technical architecture, typically employ a modular assembly structure, resulting in a large overall size and heavy weight, making them difficult to adapt to mobile field testing scenarios. Furthermore, the complex layout of their internal gas pipelines, electrical systems, and core components makes operation and maintenance inconvenient. In addition, they require technicians with specialized chromatographic analysis knowledge to perform a series of operations such as parameter adjustment, sample pretreatment, and instrument maintenance.

[0003] Currently, the market demand for portable, automated, and highly integrated gas chromatographs is increasing. While existing portable chromatographs have improved in size with advancements in scientific research, significant room for improvement remains in the integrated layout of internal core components and the coordination of automated control. In practical applications, complex gas path connections and dispersed functional components can significantly impact the stability and reliability of detection. For example, patent CN105974023A discloses a portable gas chromatography-mass spectrometry (GC-MS) device that separates the gas chromatography module, ionization source module, and mass spectrometry detector module into three independent modules. Although coaxial arrangement optimizes connection accuracy, it fails to achieve coordinated control of core components, resulting in insufficient coordination and limited response efficiency during parameter adjustment and sample detection. Another example is patent CN223624193U, which presents a portable gas chromatograph with a separate main unit, power supply, and gas source unit design. The gas path lines need to be spliced ​​according to the usage scenario, leading to complex connections and a large space requirement.

[0004] In summary, how to highly integrate and modularize core components such as injection valves, chromatographic columns, detectors, and control circuits to achieve more compact, stable, and convenient automated chromatographs is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this invention is to provide an integrated automated gas chromatograph to solve the problems mentioned in the background art, namely, the defects in the integrated layout of internal core components and the coordination of automated control in existing gas chromatographs.

[0006] This utility model is achieved using the following technical solution:

[0007] An integrated automated gas chromatograph includes a housing and a main structure disposed within the housing. The main structure includes a sample delivery module, a reaction module, a gas delivery module, an analysis module, and a control module. The outputs of the sample delivery module and the gas delivery module are respectively connected to the reaction module, and the output of the reaction module is connected to the analysis module. The control module is electrically connected to the sample delivery module, the gas delivery module, and the analysis module. The sample delivery module is used to deliver the sample gas to be detected into the reaction module, specifically including a multi-way valve. The multi-way valve has a carrier gas inlet, a gas to be detected inlet, and a sample gas outlet connected to the reaction module. The reaction module is used to separate and ionize the components in the sample gas, specifically including a reaction chamber and a flame ionization detector arranged sequentially along the sample gas flow direction. The inlet of the reaction chamber is connected to the sample gas outlet of the multi-way valve, and the outlet is connected to the flame ionization detector. A chromatographic column is disposed in the reaction chamber. The gas delivery module is used to deliver fuel gas into the flame ionization detector, specifically including a fuel gas delivery control valve. The analysis module is used to analyze gas components and generate spectra, and specifically includes a gas analysis unit, which is electrically connected to a flame ionization detector via a signal line.

[0008] This invention provides a highly integrated gas chromatograph capable of automated collaborative operation. Specifically, the core components of the chromatograph are modularly designed, with each module integrated within the housing, avoiding the problems of complex wiring, cumbersome structure, and inconvenience associated with traditional split-type structures. Furthermore, the chromatographic column and flame ionization detector are integrated into a reaction module, effectively shortening the gas path connection and reducing cold spots, thus improving gas phase analysis efficiency and sensitivity. Based on the control module, the sample delivery module, gas delivery module, and analysis module can operate automatically, and the modules can coordinate with each other, thereby achieving automated detection operations and significantly improving operational efficiency and effectiveness.

[0009] Furthermore, the sample delivery module also includes a driver electrically connected to the control module, the driver being configured to drive the multi-way valve to switch between a sample injection state and a sample delivery state; the multi-way valve is configured to: in the sample injection state, the multi-way valve receives and stores the gas to be detected; in the sample delivery state, the multi-way valve delivers the sample gas into the reaction module.

[0010] In this solution, precise and repeatable quantitative injection can be achieved by switching between the sample injection state and the sample delivery state, thus making the detection process more controllable. The multi-way valve state switching can be automated through the actuator, avoiding errors caused by manual operation.

[0011] Furthermore, the multi-way valve is equipped with a quantitative tube for temporarily storing the gas to be detected. The quantitative tube is a spiral bend with a fixed volume. The quantitative tube is configured such that, in the sample injection state, the inlet of the quantitative tube is connected to the inlet of the gas to be detected, and the outlet of the quantitative tube is not connected to the outlet of the sample gas; in the sample delivery state, the inlet of the quantitative tube is connected to the inlet of the carrier gas, and the outlet of the quantitative tube is connected to the outlet of the sample gas.

[0012] In this scheme, the use of a fixed-volume quantitative tube ensures a consistent amount of sample gas entering the chromatographic column each time, which is the foundation for quantitative analysis. Specifically, in the sample injection state, the carrier gas reaches the sample gas outlet through the carrier gas inlet, and the carrier gas path and the quantitative tube do not interfere with each other. In the sample delivery state, the carrier gas reaches the quantitative tube inlet through the carrier gas inlet to push the temporarily stored analyte gas in the quantitative tube to the sample gas outlet, thereby allowing the sample gas to reach the reaction module.

[0013] Furthermore, the fuel gas delivery control valve is electrically connected to the control module, and the outlet of the fuel gas delivery control valve is connected to the flame ionization detector.

[0014] In this scheme, the control module can control the flow of fuel gas by controlling the fuel gas supply control valve, in coordination with the operation of the sample delivery module and the reaction module. In practical applications, the flame ionization detector is preferably a hydrogen flame ionization detector (FID), which has high sensitivity, a wide linear range, and good stability for most organic compounds, making it an ideal choice for detecting hydrocarbons and other organic compounds.

[0015] Furthermore, it also includes a display module, which is electrically connected to the control module; the display module includes a local display screen disposed on the outer surface of the housing and / or a remote display screen based on a wireless communication module.

[0016] This solution provides a flexible human-machine interaction method. On-site personnel can intuitively understand the equipment status and test results through the local display screen on the casing, while the remote display screen facilitates remote monitoring and data management in the central control room or office, meeting the needs of different application scenarios.

[0017] Furthermore, it also includes a heat tracing module; the heat tracing module includes a heating layer or heating pipeline covering the multi-way valve and the reaction chamber.

[0018] In this solution, the heat tracing module enables heat tracing during sample gas transport and reaction, keeping the entire gas path from sample introduction to detection at a constant high temperature. This ensures the vaporization and stable separation of each component in the sample gas, thereby helping to improve the accuracy and repeatability of the detection results.

[0019] Furthermore, the gas analysis unit and the control module are integrated on a single circuit board, which is fixedly installed inside the housing.

[0020] In this solution, the use of an integrated circuit board makes the structure more compact and robust, and also easier to install and maintain.

[0021] Furthermore, the display module is a display module that supports external input.

[0022] This solution increases the flexibility and maintainability of the equipment; when performing parameter adjustment, equipment calibration, method development, or troubleshooting, operators can switch to manual mode to flexibly control the flow and status of each valve, facilitating debugging and optimization analysis conditions.

[0023] The beneficial effects achieved by this utility model are:

[0024] This invention provides an integrated automated gas chromatograph. By incorporating a sample delivery module, reaction module, analysis module, and control module housed within the casing, it achieves modular design and centralized arrangement of the core components. Furthermore, through electrical connections between the control module and the sample delivery module, gas delivery module, and analysis module, it enables automated operation of each module and collaborative coordination between them. Compared to existing chromatographs with a split assembly structure, dispersed functional components, and a lack of automated and collaborative control, this invention offers a more compact structure, more stable performance, and easier operation. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the composition and structure of the gas chromatograph described in this embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the sample injection state of the multi-port valve described in this embodiment of the utility model;

[0027] Figure 3 This is a schematic diagram of the sample delivery state of the multi-way valve described in this embodiment of the utility model;

[0028] In the diagram: 1. Housing; 2. Actuator; 3. Reaction chamber; 4. Multi-way valve; 5. Flame ionization detector; 6. Signal line; 7. Circuit board; 8. Display screen; 9. Fuel gas delivery control valve; 10. Gas inlet to be detected; 11. Inlet of metering tube one; 12. Carrier gas inlet one; 13. Sample gas outlet one; 14. Outlet of metering tube one; 15. Outlet of metering tube two; 16. Sample gas outlet two; 17. Carrier gas inlet two; 18. Inlet of metering tube two; 19. Gas outlet to be detected. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0030] Example 1

[0031] This embodiment provides an integrated automated gas chromatograph. Please refer to [reference needed]. Figure 1 (For ease of reading, some gas and electrical lines are not shown in the diagram; please refer to the relevant descriptions below for specific connections.) The diagram includes a square housing 1 and a main structure housed within the housing 1. The main structure includes a sample delivery module, a reaction module, a gas delivery module, a heating module, an analysis module, a display module, and a control module. Specifically:

[0032] The outputs of the sample delivery module and the gas delivery module are connected to the reaction module, and the output of the reaction module is connected to the analysis module. The control module is electrically connected to the sample delivery module, the gas delivery module, the analysis module, the heating module, and the display module. Among these:

[0033] Regarding the sample delivery module:

[0034] The sample delivery module is used to deliver the sample gas to be tested into the reaction module, and specifically includes a multi-way valve 4 and an actuator 2. The actuator 2 is electrically connected to the control module and is configured to drive the multi-way valve 4 to switch between the sample injection state and the sample delivery state. The multi-way valve 4 is configured such that: in the sample injection state, the multi-way valve 4 receives and temporarily stores the gas to be tested; in the sample delivery state, the multi-way valve 4 delivers the sample gas into the reaction module.

[0035] The multi-port valve 4 has a carrier gas inlet, a gas to be detected inlet 10, and a sample gas outlet connected to the reaction module. The multi-port valve 4 contains a metering tube for temporarily storing the gas to be detected. The metering tube is a fixed-volume spiral bend. The metering tube is configured such that: in sample injection mode, the inlet of the metering tube is connected to the gas to be detected inlet 10, and the outlet of the metering tube is not connected to the sample gas outlet; in sample delivery mode, the inlet of the metering tube is connected to the carrier gas inlet, and the outlet of the metering tube is connected to the sample gas outlet.

[0036] Please refer to Figure 2 and Figure 3 Specifically, in this embodiment:

[0037] There are two carrier gas inlets, namely carrier gas inlet 12 and carrier gas inlet 2 17; in addition to one gas to be detected inlet 10, there is also one gas to be detected outlet 19; there are two quantitative tubes, namely quantitative tube 1 and quantitative tube 2; there are two sample gas outlets, namely sample gas outlet 13 and sample gas outlet 2 16; carrier gas inlet 12, gas to be detected inlet 10, quantitative tube 1 and sample gas outlet 13 are located on the same side, and carrier gas inlet 2 17, gas to be detected outlet 19, quantitative tube 2 and sample gas outlet 2 16 are located on the same side.

[0038] In the sample introduction state, the gas to be detected inlet 10 is connected to the inlet 11 of quantitative tube one, the outlet 14 of quantitative tube one is connected to the outlet 15 of quantitative tube two, and the inlet 18 of quantitative tube two is connected to the gas to be detected outlet 19; the carrier gas inlet one 12 is connected to the sample gas outlet one 13, and the carrier gas inlet two 17 is connected to the sample gas outlet two 16; the sample gas outlet one 13 and the sample gas outlet two 16 are respectively connected to the reaction module. Based on this, the external gas to be detected is pumped into the gas to be detected inlet 10, and then flows through and fills the quantitative tube one and quantitative tube two with a fixed volume. Excess gas is discharged from the gas to be detected outlet 19 (as an vent). At this time, the carrier gas (such as hydrocarbon-free air) enters from the carrier gas inlet one 12 and the carrier gas inlet two 17 respectively, but does not pass through quantitative tube one and quantitative tube two, but flows directly to the reaction module (or vents) through the sample gas outlet one 13 and the sample gas outlet two 16.

[0039] In the sample delivery state, the gas inlet 10 is connected to the gas outlet 19; the carrier gas inlet 12 is connected to the inlet 11 of the first metering tube, and the outlet 14 of the first metering tube is connected to the sample gas outlet 13; the carrier gas inlet 2 17 is connected to the inlet 18 of the second metering tube, and the outlet 15 of the second metering tube is connected to the sample gas outlet 2 16; the sample gas outlet 13 and the sample gas outlet 2 16 are respectively connected to the reaction module. Based on this, the high-pressure carrier gas flows through the first and second metering tubes respectively to push the gas to be detected stored in the tubes to the sample gas outlet 13 and the sample gas outlet 2 16, thereby allowing the sample to be delivered into the reaction module.

[0040] The driver 2 is specifically an electromagnetic driver or a stepper motor. It receives instructions from the control module and can precisely drive the valve core of the multi-way valve 4 to rotate to a specified position. The multi-way valve 4 can change the connection mode of the internal flow path by rotating the valve core, thereby realizing the switching between two states.

[0041] Regarding the reaction module, heat tracing module, gas supply module, analysis module, control module, and display module:

[0042] The reaction module is used to separate and ionize the components in the sample gas, specifically including a reaction chamber 3 and a flame ionization detector 5 arranged sequentially along the sample gas flow direction. The reaction chamber 3 is a precision-machined metal block (such as stainless steel) with good thermal conductivity, an internal hollow space, and is enclosed by a heat tracing module. In this embodiment, the heat tracing module also encloses the periphery of the multi-way valve 4. Specifically, the heat tracing module employs a heating layer (not shown in the figure; or may use a heating pipeline or other structural form) electrically connected to the control module and a temperature sensor.

[0043] A chromatographic column (not shown in the figure) is installed in the hollow space of reaction chamber 3. The inlet of reaction chamber 3 is connected to the sample gas outlet of multi-port valve 4, and the outlet is connected to flame ionization detector 5. In this embodiment, the chromatographic column is a packed column or a capillary column, which is filled with or has its inner wall coated with a specific stationary phase material; the flame ionization detector 5 is a hydrogen flame ionization detector, which includes a nozzle, a collecting electrode, and an ignition device; the fuel gas includes air as a combustion-supporting gas and hydrogen as a combustible gas.

[0044] The gas delivery module is used to deliver fuel gas into the flame ionization detector 5, and specifically includes a fuel gas delivery control valve 9 electrically connected to the control module. The analysis module is used to analyze the gas components and generate spectra, and specifically includes a gas analysis unit electrically connected to the control module. The gas analysis unit is electrically connected to the flame ionization detector 5 via a signal line 6. The gas analysis unit and the control module are integrated on a circuit board 7, which is fixedly mounted on the inner wall of the housing 1.

[0045] The control module includes a microprocessor, memory, and communication unit. The display module is electrically connected to the control module and includes a local display screen 8 mounted on the outer surface of the housing 1 and a remote display screen based on a wireless communication module; both the local display screen 8 and the remote display screen support external input. Users can view data and perform manual interventions through the two displays, such as starting / stopping detection, adjusting valve flow, and controlling detection parameters.

[0046] The overall workflow of the above-mentioned chromatograph is as follows:

[0047] Preparation: After the instrument is powered on, the heating module starts working, heating the gas system to the set temperature. Hydrogen and air enter the flame ionization detector 5 through the fuel gas supply control valve 9 and complete ignition.

[0048] Sample injection and delivery: The control module controls the driver 2 to switch the multi-way valve 4 to the sample injection state, so that the gas to be detected fills the quantitative tube; after the sample injection state is maintained for a specific time, the multi-way valve 4 is switched to the sample delivery state to deliver the sample gas into the reaction module.

[0049] Separation and detection: The sample gas sent out by the multi-port valve 4 will first enter the chromatographic column in the reaction chamber 3; when the sample gas containing mixed components flows through the chromatographic column, due to the different interaction forces (such as adsorption forces) between each gas component and the stationary phase, the movement speed is also different, so separation can be achieved, so that the gas components with stronger interaction forces exit the column later and the gas components with weaker interaction forces exit the column first.

[0050] After separation, the gas components flow out sequentially from the end of the chromatographic column and enter the adjacent flame ionization detector 5. Hydrogen and air, precisely controlled by the fuel gas supply control valve 9, are also fed into the flame ionization detector 5 and ignited by the internal ignition device to form a stable hydrogen flame. When the gas components containing organic matter enter the flame, a complex ionization reaction occurs, generating a weak ion flow. The flame ionization detector 5 is equipped with a pair of electrodes (the nozzle itself can serve as one electrode, with a collecting electrode above it). By applying a DC voltage between the electrodes, the ion flow can be directed under the influence of an external electric field, forming a weak current signal. The intensity of this current signal is proportional to the mass of organic matter entering the flame.

[0051] Data processing and display: Signal line 6 collects the current signal and transmits it to the gas analysis unit. The gas analysis unit receives and amplifies the weak current signal, digitizes it through the built-in analog-to-digital converter, and then the built-in microprocessor draws a chromatogram based on the time series. Subsequently, the analysis program written in the microprocessor performs calculations such as peak area integration and standard curve calibration to obtain the concentration of each gas component.

[0052] Under the coordinated control of the control module, the chromatogram and the concentration information of each gas component are displayed on the local display screen 8 and the remote display screen.

[0053] It should be noted that the parts not described in detail or in detail in this article, such as the specific structure and working principle of components such as the chromatographic column, flame ionization detector 5, gas analysis unit, driver 2, and valve core of multi-way valve 4, are all existing technologies and are not improvements made by this utility model to the existing technology, nor are they within the protection scope of the technical solution of this utility model. Therefore, they will not be elaborated on in this article.

[0054] Of course, the above description is only a preferred embodiment of this utility model and should not be considered as limiting the scope of the embodiments of this utility model. This utility model is not limited to the above examples, and all equivalent changes and improvements made by those skilled in the art within the scope of this utility model should be included in the patent coverage of this utility model.

Claims

1. An integrated automated gas chromatograph, comprising a housing (1) and a main structure disposed inside the housing (1), characterized in that: The main structure includes a sample delivery module, a reaction module, a gas delivery module, an analysis module, and a control module; the output terminals of the sample delivery module and the gas delivery module are respectively connected to the reaction module, the output terminal of the reaction module is connected to the analysis module, and the control module is electrically connected to the sample delivery module, the gas delivery module, and the analysis module respectively. The sample delivery module includes a multi-way valve (4); the multi-way valve (4) has a carrier gas inlet, a gas to be detected inlet (10) and a sample gas outlet connected to the reaction module; The reaction module includes a reaction chamber (3) and a flame ionization detector (5) arranged sequentially along the sample gas flow direction; the inlet of the reaction chamber (3) is connected to the sample gas outlet of the multi-way valve (4), and the outlet is connected to the flame ionization detector (5); a chromatographic column is provided in the reaction chamber (3). The gas delivery module includes a fuel gas delivery control valve (9); The analysis module includes a gas analysis unit, which is electrically connected to the flame ionization detector (5) via a signal line (6).

2. The integrated automated gas chromatograph according to claim 1, characterized in that: The sample delivery module also includes a driver (2) electrically connected to the control module, the driver (2) being configured to drive the multi-way valve (4) to switch between the sample injection state and the sample delivery state; The multi-way valve (4) is configured such that: in the sample injection state, the multi-way valve (4) receives and stores the gas to be detected; in the sample delivery state, the multi-way valve (4) delivers the sample gas into the reaction module.

3. The integrated automated gas chromatograph according to claim 2, characterized in that: The multi-way valve (4) is equipped with a metering tube for storing the gas to be detected. The metering tube is a spiral bend with a fixed volume. The quantitative tube is configured such that: in the sample injection state, the inlet of the quantitative tube is connected to the inlet of the gas to be detected (10), and the outlet of the quantitative tube is not connected to the outlet of the sample gas; in the sample delivery state, the inlet of the quantitative tube is connected to the inlet of the carrier gas, and the outlet of the quantitative tube is connected to the outlet of the sample gas.

4. The integrated automated gas chromatograph according to claim 1, characterized in that: The fuel gas delivery control valve (9) is electrically connected to the control module, and the outlet of the fuel gas delivery control valve (9) is connected to the flame ionization detector (5).

5. The integrated automated gas chromatograph according to claim 1, characterized in that: It also includes a display module, which is electrically connected to the control module; the display module includes a local display screen (8) disposed on the outer surface of the housing (1) and / or a remote display screen based on a wireless communication module.

6. The integrated automated gas chromatograph according to claim 1, characterized in that: It also includes a heat tracing module; the heat tracing module includes a heating layer or heating pipeline covering the multi-way valve (4) and the reaction chamber (3).

7. The integrated automated gas chromatograph according to claim 1, characterized in that: The gas analysis unit and control module are integrated on a circuit board (7), which is fixedly installed inside the housing (1).

8. The integrated automated gas chromatograph according to claim 5, characterized in that: The display module is a display module that supports external input.

Images