Gas chromatography automatic sampling device and method for detecting organic sulfides

Abstract

The application discloses a kind of organic sulfide detection gas chromatography automatic sampling device and method, its pipeline purging system is by purging gas cylinder, electric control valve and diffusion port, for the purging diffusion of sample gas sampling storage system;Sample gas sampling storage system is by gas sampling bag, electric three-way valve, gas sampling steel bottle, pressure gauge, vacuum pump, the gas storage tank to be measured and electromagnetic stirrer, for the storage and mixing of to-be-measured sample gas;High-precision quantitative sampling system is by electric control valve, electric three-way valve, standard gas cylinder, vacuum pump, mass flow meter and chromatographic sampling port, for the sampling of sample gas;And through controller control valve, pump, pressure, flow and the like parameter.The application can realize continuous stable sampling, is equipped with passivation pipeline and continuous back-blowing cleaning function, eliminates sample pollution, is equipped with electromagnetic stirring function, improves sampling uniformity, can effectively solve the error of current manual sampling, complex operation, cannot stable sampling and other problems.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of automatic sampling of a gas chromatograph, in particular to a gas chromatograph automatic sampling device and method for detecting organic sulfides. BACKGROUND

[0002] A gas chromatograph is an instrument for qualitatively and quantitatively analyzing complex multi-component mixed gas by using chromatographic separation technology and detection technology. The gas chromatograph generally comprises a sampling system, a gas path system, a chromatographic column separation system, a control and detection system, an analysis software workstation and the like. For detection of organic sulfides in metallurgical coal gas, a high-precision sampling system is particularly important. Since organic sulfides are prone to adhere to the inside of a gas pipeline or a needle cylinder, causing detection deviation, currently, a pipeline subjected to passivation treatment is used for sampling of the organic sulfides in gas. The specific sampling operation is as follows: a sample bag or bottle (with pressure) to be detected is connected to a chromatographic sampling port, a valve of the sample bag or bottle is opened, the sample in the sample bag is manually squeezed to make the gas in the bag enter the gas chromatograph, and then a chromatographic sampling program is started, and when the sample gas completely fills a quantitative ring for detection, the sampling action is completed; for the sample in the sample bottle, the sample bottle is used to enter the gas chromatograph by using the gas pressure in the bottle, and when the sample gas completely fills the quantitative ring for detection, the sampling action is completed. The existing sampling mode has the following technical problems: (1) when the sample bag is used for sampling, the sampling flow cannot be stably controlled due to manual squeezing for sampling, the repeatability error of sampling is large, and time and labor are consumed; and (2) when the sample bottle is used for sampling, the sampling flow can be controlled by a valve, but the sample bottle pressure decreases after multiple samplings, the sample cannot be stably sampled for multiple times, and if the volume or pressure of the sample bottle is increased, the error of the sample will be caused, and the detection result is affected.

[0003] Through retrieval, patent No. CN116953137A discloses a full-automatic sampling device for gas chromatographic detection, patent No. CN101819193B discloses a multifunctional gas chromatograph automatic sampler, patent No. CN110609105A discloses a gas chromatograph automatic sampling device, patent No. CN214334806U discloses a gas chromatograph automatic sampler, patent No. CN212932516U discloses a gas chromatograph automatic sampling device, and patent No. CN209372773U discloses a gas chromatograph automatic sampler. It can be known from the above-mentioned retrieved patents that there are many automatic sampling devices for gas chromatographs at present, but the automatic sampling devices and methods are mainly for needle sampling, and there are few automatic sampling devices and methods for sample bag and sample bottle sampling. SUMMARY

[0004] The purpose of this invention is to provide an automated gas chromatography injection device and method for the detection of organic sulfides. It can achieve high-precision automated injection of gas cylinder and gas bag samples as well as fully automated injection of gaseous standards. It can be linked with a gas chromatograph to significantly reduce the errors caused by manual injection. It can be used for automated injection of various gas samples, simplifying operation steps and improving injection uniformity, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An automated gas chromatographic injection device for detecting organic sulfides includes a purge gas cylinder, a gas sampling bag, a gas sampling cylinder, a standard gas cylinder, a test gas storage tank, a controller, a vent, and a chromatographic injection port. The purge gas cylinder is connected to the test gas storage tank via a gas-liquid path. An electromagnetic stirrer is installed inside the test gas storage tank. One end of the gas-liquid path is equipped with an electrically controlled valve. The gas-liquid path output through the electrically controlled valve is divided into two branches connected in parallel to the test gas storage tank. Electric three-way valves are installed on the two branches. One branch's electric three-way valve is connected to the gas sampling bag, and the other... The branch circuit's electric three-way valve is connected to the gas sampling cylinder. A pressure gauge, vacuum pump, and electrically controlled valve are also installed on the gas-liquid circuit after the two branches are connected in parallel. The standard gas cylinder is connected to the vent and chromatographic inlet via a gas-liquid circuit, and a corresponding electric three-way valve and mass flow meter are installed on the connecting pipeline. An electrically controlled valve and vacuum pump are correspondingly installed on the gas-liquid circuit connecting the test gas storage tank and the standard gas cylinder. The electrically controlled valve, electric three-way valve, pressure gauge, vacuum pump, electromagnetic stirrer, and mass flow meter are all electrically connected to the controller via signal transmission lines.

[0007] Preferably, the purge gas cylinder is filled with nitrogen gas, and the purge gas cylinder, the electrically controlled valve and the venting port constitute a pipeline purging system for purging and venting the entire sample injection device.

[0008] Preferably, the vent pipe is made of stainless steel with a diameter of 1 / 8 inch, and is vented outdoors or into a fume hood together with the gas chromatograph vent pipe.

[0009] Preferably, the gas sampling bag, electric three-way valve, gas sampling cylinder, pressure gauge, vacuum pump, test gas storage tank and electromagnetic stirrer constitute a sample gas injection and storage system. The gas sampling bag and gas sampling cylinder are the test samples brought back from the field. The test samples are drawn into the test gas storage tank for storage by the vacuum pump.

[0010] Preferably, the vacuum pump is an oil-free diaphragm pressurizing pump with PTFE gaskets inside. Its pressurization range is 0 to 0.5 MPa, and its vacuum degree is -81 kPa. It is equipped with signal input and output to transmit operating parameters to the controller, and the controller controls the start and stop of the vacuum pump.

[0011] Preferably, the gas storage tank is equipped with electrically controlled valves in both the front and rear pipelines, a pressure gauge is installed on the gas storage tank, the volume of the gas storage tank is -L, the outer shell is made of stainless steel, and the inner wall is made of polytetrafluoroethylene.

[0012] Preferably, the electromagnetic stirrer is used to mix the gas inside the gas storage tank to be tested evenly. Its impeller and blades are wrapped with polytetrafluoroethylene material. The impeller and blades contain magnets. The speed of the impeller is controlled by the electromagnetic stirrer to be 0-5000 RPM. The electromagnetic stirrer is equipped with signal input and output to transmit the operating parameters to the controller, and the controller controls the start and stop of the electromagnetic stirrer and the operating parameters.

[0013] Preferably, the electrically controlled valve, electric three-way valve, standard gas cylinder, vacuum pump, mass flow meter and chromatographic injection port constitute a high-precision quantitative injection system. The system extracts the sample to be tested from the gas storage tank through the vacuum pump, controls the injection flow rate through the mass flow meter, and sends it to the gas chromatograph.

[0014] Preferably, the controller is equipped with an interface for communication with the chromatography host, used for automatic sample injection and synchronous control of chromatography. The controller forms feedback control with each system through feedback signals, and realizes the working mode of sample injection and purging by controlling the opening and closing of different valves and the start and stop of pumps.

[0015] This invention provides another technical solution: a method for automated gas chromatography injection for the detection of organic sulfides, based on an automated gas chromatography injection device for the detection of organic sulfides, comprising the following steps:

[0016] S1: Turn on the automatic sampler: The device automatically enters the self-test state and performs a self-test on all valves in the system. If the self-test passes, the system will prompt you to connect the gas sampling bag / gas sampling cylinder. If the self-test fails, the system will prompt that the self-test has failed and that you should repair the instrument. After repair, repeat S1.

[0017] S2: Sample connection: Connect to different interfaces depending on the sample. If it is a gas sampling bag, connect to the electric three-way valve at the gas sampling bag interface. If it is a gas sampling cylinder, connect to the electric three-way valve at the gas sampling cylinder interface. After connecting the sample, open the sealing valve of the gas sampling bag / gas sampling cylinder.

[0018] S3: After the sample is connected, the system automatically determines whether the sample connection is airtight. If a leak is detected, it will indicate that the sample is not connected properly. Please reconnect the sample and repeat S2. If the test passes, proceed to the next stage.

[0019] S4: After S3 is completed, select the purging mode in the controller and set the corresponding purging time; after setting, the system will automatically enter the purging mode and automatically stop purging after the set purging time is reached.

[0020] S5: After the purging is completed, a prompt will appear asking whether to enter the sample injection state. If yes is selected, the system will automatically enter the sample injection state; if no is selected, the system will enter the stop state and end the sample injection.

[0021] S6: When the system enters the sample injection state and then exits the sample injection state, the system prompts you to select the injection mode, which is gas bag mode, gas cylinder mode, or standard gas mode.

[0022] S7: If the standard gas mode is selected, the system will enter the standard gas mode and start the standard gas injection. After one injection is completed, the system will prompt whether to continue or stop the injection. Choose according to the chromatographic requirements. If no is selected, the system will return to the standard gas injection state and continue the injection. If yes is selected, the system will enter the stop state and end the standard gas injection.

[0023] S8: If the gas bag mode is selected, the system will automatically enter the gas bag mode; if the gas cylinder mode is selected, the system will automatically enter the gas cylinder mode. At this time, the system will prompt whether to start pre-injection. If yes is selected, the system will enter the pre-injection state; if no is selected, the system will enter the stop state and end the injection.

[0024] S9: After the pre-injection state is completed, the system prompts whether to inject the sample. If you select yes, the system will enter the injection state. After one injection is completed, the system will automatically enter the pause injection state. If you select no, the system will directly enter the pause injection state.

[0025] S10: When entering the pause injection state, the system prompts whether to continue injection. You need to judge according to the actual situation. If you need to continue injection, the system will return to the injection state and continue injection. If you choose no, the system will return to the purge state. The default purge time is 5 minutes. After the purge is completed, return to S5.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] The automated gas chromatography injection device and method for detecting organic sulfides of the present invention effectively solves the problems of detection errors caused by manual squeezing injection when using sample bags in gas chromatographs for organic sulfur detection, which makes it difficult to stably control the injection flow rate and pressure. It also addresses the issue of sample vial injection where pressure drops after multiple injections, making stable multiple injections impossible. By designing a fully automated injection device and control system, continuous and stable injection is achieved. Equipped with passivated tubing and continuous backflush cleaning functions to prevent sample contamination, and an electromagnetic stirring function to improve injection uniformity, the invention effectively solves the problems of large errors, complex operation, and unstable injection associated with current manual injection methods. Attached Figure Description

[0028] Figure 1 This is a block diagram of the device structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the conduction principle of the electric three-way valve of the present invention;

[0030] Figure 3 This is a flowchart of the method of the present invention.

[0031] In the diagram: 1. Purge gas cylinder; 2. Electrically controlled valve; 3. Gas sampling bag; 4. Electric three-way valve; 5. Gas sampling cylinder; 6. Pressure gauge; 7. Standard gas cylinder; 8. Vacuum pump; 9. Test gas storage tank; 10. Electromagnetic stirrer; 11. Mass flow meter; 12. Controller; 13. Vent port; 14. Chromatographic injection port. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Please see Figure 1 This invention provides an automated gas chromatography (GC) injection device for detecting organic sulfides, comprising a purge gas cylinder 1, a gas sampling bag 3, a gas sampling cylinder 5, a standard gas cylinder 7, a test gas storage tank 9, a controller 12, a vent port 13, and a chromatographic injection port 14. The purge gas cylinder 1 is connected to the test gas storage tank 9 via a gas-liquid path. An electromagnetic stirrer 10 is installed inside the test gas storage tank 9. One end of its gas-liquid path is equipped with an electrically controlled valve 2. The gas-liquid path output through the electrically controlled valve 2 is divided into two branches connected in parallel to the test gas storage tank 9. Electric three-way valves 4 are installed on the two branches respectively. One branch of the electric three-way valve 4 is connected to the gas sampling bag 3. One branch of the electric three-way valve 4 is connected to the gas sampling cylinder 5. The gas-liquid line after the two branches are connected in parallel is also equipped with a pressure gauge 6, a vacuum pump 8, and an electrically controlled valve 2. The standard gas cylinder 7 is connected to the vent 13 and the chromatographic injection port 14 through a gas-liquid line, and a corresponding electric three-way valve 4 and a mass flow meter 11 are installed on the connecting pipe. The gas-liquid line connecting the test gas storage tank 9 and the standard gas cylinder 7 is equipped with an electrically controlled valve 2 and a vacuum pump 8. The electrically controlled valve 2, the electric three-way valve 4, the pressure gauge 6, the vacuum pump 8, the electromagnetic stirrer 10, and the mass flow meter 11 are all electrically connected to the controller 12 through a signal transmission line.

[0034] In this embodiment of the invention, the purge gas cylinder 1 contains nitrogen gas with a purity requirement of 99.999%. The purge gas cylinder 1, the electrically controlled valve 2, and the vent 13 constitute a pipeline purging system for purging and venting the entire sample injection device. The purge gas is depressurized (to 0.1-1 MPa) from the purge gas cylinder 1 by the electrically controlled valve 2 and then used to purge the sample injection pipeline by controlling the switch of the electrically controlled valve 2. Finally, it is discharged through the vent 13. The electrically controlled valve 2 is equipped with a signal input / output system that can be connected to the controller 12 for control. The valve is made of PTFE and the valve opening and closing sends a clear signal to the controller 12 with a response time ≤0.5S. The vent 13 is made of stainless steel with a diameter of 1 / 8 inch and is vented outdoors or into a fume hood along with the gas chromatograph vent tube.

[0035] In this embodiment of the invention, the gas sampling bag 3, electric three-way valve 4, gas sampling cylinder 5, pressure gauge 6, vacuum pump 8, test gas storage tank 9, and electromagnetic stirrer 10 constitute a sample gas injection and storage system. The gas sampling bag 3 and gas sampling cylinder 5 are the test samples brought back from the field. The test samples are drawn into the test gas storage tank 9 by the vacuum pump 8 for storage. The choice between using the gas sampling bag 3 and the gas sampling cylinder 5 for sampling depends on the field sampling environment. Only one of them is connected during sample injection, and both the gas sampling bag 3 and the gas sampling cylinder are used. All 5 are connected to the electric three-way valve 4 (T01, T02) via pipelines. After confirming the connection, open the valve on the gas sampling bag 3 or the gas sampling cylinder 5. The electric three-way valve 4 can achieve two-to-two connection and complete disconnection of the three ports. The valve body is made of PTFE and is equipped with a signal input and output system, which can be connected to the controller 12 for control of the open circuit. The response time is ≤0.5S. The pressure gauge 6 is equipped with a signal output, which can transmit the pressure signal to the controller 12. The pressure gauge 6 has a range of -0.1 to 1MPa.

[0036] In this embodiment of the invention, the vacuum pump 8 is an oil-free diaphragm pressurizing pump with a PTFE gasket inside. Its pressurization range is 0 to 0.5 MPa, and its vacuum degree is -81 kPa. It is equipped with signal input and output to transmit operating parameters to the controller 12, and the controller 12 controls the start and stop of the vacuum pump 8.

[0037] In the above embodiment, the front and rear pipelines of the gas storage tank 9 are equipped with electrically controlled valves 2, and the gas storage tank 9 is equipped with a pressure gauge 6. The volume of the gas storage tank 9 is 1-2L, the outer shell is made of stainless steel, and the inner wall is made of polytetrafluoroethylene (PTFE) to prevent the sample gas from being adsorbed inside the gas storage tank 9 and causing inaccurate detection. The gas storage tank 9 is equipped with an electromagnetic stirrer 10, which is used to control the rotation of the impeller blades to make the gas inside the gas storage tank 9 mixed evenly. The impeller and blades are wrapped with PTFE material, and the impeller and blades contain magnets. The speed of the impeller is controlled by the electromagnetic stirrer 10 from 0-5000 RPM. The electromagnetic stirrer 10 is equipped with signal input and output to transmit the operating parameters to the controller 12, and the controller 12 controls the start and stop of the electromagnetic stirrer 10 and the operating parameters, etc.

[0038] In this embodiment of the invention, the electrically controlled valve 2, the electric three-way valve 4, the standard gas cylinder 7, the vacuum pump 8, the mass flow meter 11, and the chromatographic injection port 14 constitute a high-precision quantitative injection system. The system uses the vacuum pump 8 to extract the sample from the test gas storage tank 9, and the mass flow meter 11 controls the injection flow rate to deliver it to the gas chromatograph. The standard gas cylinder 7 is used for calibrating the chromatogram. The standard gas is determined based on the composition of the test sample, and multiple concentration gradients can be set to create a standard curve. The standard gas from the standard gas cylinder 7 is depressurized (to 0.1–0.5 MPa) by a pressure reducing valve and then controlled by a control valve. A switch is used to control the flow rate of the mass flow meter 11 to the chromatograph. The vacuum pump 8 is consistent with the model and parameters used in the gas storage tank 9. The mass flow meter 11 is electrically controlled and has a signal input / output system that can be connected to the controller 12 for control and parameter setting. The mass flow meter 11 has a range of 0 to 200 sccm, accuracy of ±(0.8% of the reading + 0.2% of the full scale), repeatability of ±0.2% of the full scale, control response time ≤100ms, and real-time flow display. The internal material of the flow meter is fluororubber.

[0039] In the above embodiments, the controller 12 is provided with an interface for communication with the chromatography host, which is used for automatic sample injection and synchronous control of chromatography. The controller 12 forms feedback control with each system through feedback signals, and realizes the working mode of sample injection and purging by controlling the opening and closing of different valves and the start and stop of pumps.

[0040] In actual use, all valves in the entire system are in the closed state by default. Different states are achieved by controlling the valves, as follows:

[0041] State 1: Purge Mode: Select purging mode in the control panel. At this time, the system controls the opening of electrically controlled valves 2 (S01, S02), and the passage of the electric three-way valve 4 (T01, T02) is 1-3 (e.g., Figure 2As shown), vacuum pump 8 starts working, electromagnetic stirrer 10 starts working (speed is 1500 rpm), when pressure gauge 6 (PO2) reaches 0.2 MPa, electric control valve 2 (S03) opens, vacuum pump 8 in the gas storage tank 9 starts working, electric three-way valve 4 (T03) is in the 2-3 passage, mass flow meter 11 is in the maximum range, electric three-way valve 4 (T04) is in the 1-2 passage, purge gas is released through vent 13, purge ends according to the purge time set by controller 12 and purge mode stops.

[0042] State 2: Purge stopped: ready for sample injection; at this time, the electric control valve 2 (S01) is closed. When the pressure gauge 6 (P01) reaches -80Kpa, the vacuum pump 8 in front of the gas storage tank 9 stops working, the electric three-way valve 4 (T01, T02) is closed, and the electric control valve 2 (S02) is closed. When the pressure gauge 6 (P02) reaches -80Kp, the vacuum pump 8 behind the gas storage tank 9 stops working, and the electric control valve 2 (S03) is closed. When the reading of the mass flow meter 11 is <1sccm, the electric three-way valve 4 (T04) is closed.

[0043] State 3: Pre-injection state. At this time, the vacuum pump 8 in front of the gas storage tank 9 starts to work, and the electromagnetic stirrer 10 starts to work (the speed is 2500 rpm, which can be adjusted by the controller 12). When the pressure gauge 6 (P02) reaches 0.2 MPa or the pressure gauge 6 (P01) reaches -80 kPa, the vacuum pump 8 in front of the gas storage tank 9 stops working, and the electric control valve 2 (S02) closes.

[0044] State 4: Sample injection state. At this time, the electric control valve 2 (S03) is open, the rear vacuum pump 8 of the gas storage tank 9 starts to work, the electric three-way valve 4 (T03) is in the 2-3 path, the mass flow meter 11 controls the flow rate to 80 sccm, the electric three-way valve 4 (T04) is in the 1-3 path, and the sample gas enters the chromatograph through the chromatograph injection port 14.

[0045] State 5: Sample injection paused. At this time, the electric control valve 2 (S03) is closed, the vacuum pump 8 of the gas storage tank 9 stops working, the mass flow meter 11 stops working, and the electric three-way valve 4 (T04) is closed.

[0046] State 6: Sample gas shortage. When pressure gauge 6 (P02) reaches -50 kPa, the electric control valve 2 (S03) closes, the vacuum pump 8 of the test gas storage tank 9 stops working, the electromagnetic stirrer 10 stops working, the mass flow meter 11 stops working, the electric three-way valve 4 (T04) closes, and the system prompts a sample gas shortage alarm.

[0047] State 7: Stopped state. All valves are returned to the closed state, and all equipment such as mass flow meter 11, vacuum pump 8, and electromagnetic stirrer 10 have stopped operating.

[0048] Mode 1: Airbag Mode: Select airbag mode in the control panel. At this time, the system controls the electric valve 2 (S02) to open, and the electric three-way valve 4 (T01) to open the passage 2-3.

[0049] Mode 2: Sample Bottle Mode: Select the gas cylinder mode in the control panel. At this time, the system controls the electric valve 2 (S02) to open, and the electric three-way valve 4 (T02) to have passages 2-3.

[0050] Mode 3: Standard gas mode. Select standard gas mode in the control panel. At this time, the electric three-way valve 4 (T03, T04) is in the 1-3 passage, all other valves are closed, the mass flow meter 11 controls the flow rate to 80 sccm, and the standard gas enters the chromatograph through the chromatograph injection port 14.

[0051] In the above embodiments, except for the pipes with specially specified materials, the embodiments of the present invention require that the material be Hastelloy passivated, and that all metal parts in direct contact with the sample gas be coated or passivated, with a pipe diameter of 1 / 8 inch, to ensure that the system does not adsorb the sample gas during the sampling process.

[0052] Please see Figure 3 To further explain the embodiments of the present invention, a method for automated gas chromatography injection for the detection of organic sulfides is also provided, comprising the following steps:

[0053] S1: Turn on the automatic sampler: The device automatically enters the self-test state and performs a self-test on all valves in the system. After the self-test passes, the system prompts to connect the gas sampling bag 3 / gas sampling cylinder 5. If the self-test fails, it prompts that the self-test has failed and the instrument should be repaired. After repair, repeat S1.

[0054] S2: Sample connection: Connect to different interfaces depending on the sample. If it is a gas sampling bag 3, connect to the electric three-way valve 4 at the interface of the gas sampling bag 3. If it is a gas sampling cylinder 5, connect to the electric three-way valve 4 at the interface of the gas sampling cylinder 5. After connecting the sample, open the sealing valve of the gas sampling bag 3 / gas sampling cylinder 5.

[0055] S3: After the sample is connected, the system automatically determines whether the sample connection is airtight. If a leak is detected, it will indicate that the sample is not connected properly. Please reconnect the sample and repeat S2. If the test passes, proceed to the next stage.

[0056] S4: After S3 is completed, select the purging mode in controller 12 and set the corresponding purging time; after setting, the system will automatically enter the purging mode and stop purging automatically after the set purging time is reached.

[0057] S5: After the purging is completed, a prompt will appear asking whether to enter the sample injection state. If yes is selected, the system will automatically enter the sample injection state; if no is selected, the system will enter the stop state and end the sample injection.

[0058] S6: When the system enters the sample injection state and then exits the sample injection state, the system prompts you to select the injection mode, which is gas bag mode, gas cylinder mode, or standard gas mode.

[0059] S7: If the standard gas mode is selected, the system will enter the standard gas mode and start the standard gas injection. After one injection is completed, the system will prompt whether to continue or stop the injection. Choose according to the chromatographic requirements. If no is selected, the system will return to the standard gas injection state and continue the injection. If yes is selected, the system will enter the stop state and end the standard gas injection.

[0060] S8: If the gas bag mode is selected, the system will automatically enter the gas bag mode; if the gas cylinder mode is selected, the system will automatically enter the gas cylinder mode. At this time, the system will prompt whether to start pre-injection. If yes is selected, the system will enter the pre-injection state; if no is selected, the system will enter the stop state and end the injection.

[0061] S9: After the pre-injection state is completed, the system prompts whether to inject the sample. If you select yes, the system will enter the injection state. After one injection is completed, the system will automatically enter the pause injection state. If you select no, the system will directly enter the pause injection state.

[0062] S10: When entering the pause injection state, the system prompts whether to continue injection. You need to judge according to the actual situation. If you need to continue injection, the system will return to the injection state and continue injection. If you choose no, the system will return to the purge state. The default purge time is 5 minutes. After the purge is completed, return to S5.

[0063] In summary, the gas chromatography automatic sampling device and method for detecting organic sulfides provided by the present invention are to solve the problems of detection errors caused by the inability to stably control the sampling flow rate and pressure during manual extrusion sampling when using a sample bag for sampling in a gas chromatograph during the detection of organic sulfur, and the inability to stably perform multiple samplings due to the decrease in the pressure of the sample bottle after multiple samplings when using a sample bottle for sampling. By designing a fully automated sampling device and control system, the storage and high-precision stable sampling of the sample gas to be measured can be achieved. The device uses a fully automated control system to control the sampling, which can be directly linked with the chromatograph, reducing the errors caused by manual sampling and meeting the continuous detection requirements of a single sample. Secondly, the controller controls valves, pumps, flow meters, sample gas storage tanks, electromagnetic stirrers, etc. to achieve the full-automatic sampling of the sample gas to be measured and the sampling control of the standard gas. A control logic is formed between the pressure sensor and the controller, and a communication interface is reserved between the controller and the mainframe of the chromatograph, enabling linkage control and quantitative sampling, etc. The sampling system is equipped with passivated pipelines and a continuous backflush cleaning function, which can prevent sample contamination. The sample gas storage tank is equipped with an electromagnetic stirring function, which can eliminate the shaking step before sampling with a sample bottle and improve the sampling uniformity.

[0064] As described above, the above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, should be covered within the protection scope of the present invention.

Claims

1. An automated gas chromatographic sampler for the detection of organic sulfides, characterized in that, The system includes a purge gas cylinder (1), a gas sampling bag (3), a gas sampling cylinder (5), a standard gas cylinder (7), a test gas storage tank (9), a controller (12), a vent (13), and a chromatographic inlet (14). The purge gas cylinder (1) is connected to the test gas storage tank (9) via a gas-liquid circuit. An electromagnetic stirrer (10) is installed inside the test gas storage tank (9). One end of its gas-liquid circuit is equipped with an electrically controlled valve (2). The gas-liquid circuit output through the electrically controlled valve (2) is divided into two branches connected in parallel to the test gas storage tank (9). Electric three-way valves (4) are installed on the two branches respectively. One branch of the electric three-way valve (4) is connected to the gas sampling bag (3), and the other branch of the electric three-way valve (4) is connected to the gas sampling bag (3). The gas cylinder (5) is connected, and a pressure gauge (6), a vacuum pump (8), and an electric control valve (2) are installed on the gas-liquid line after the two branches are connected in parallel. The standard gas cylinder (7) is connected to the vent (13) and the chromatographic injection port (14) through the gas-liquid line, and a corresponding electric three-way valve (4) and a mass flow meter (11) are installed on the connecting pipe. The gas-liquid line connecting the gas storage tank (9) to the standard gas cylinder (7) is equipped with an electric control valve (2) and a vacuum pump (8). The electric control valve (2), electric three-way valve (4), pressure gauge (6), vacuum pump (8), electromagnetic stirrer (10), and mass flow meter (11) are all electrically connected to the controller (12) through the signal transmission line. The electrically controlled valve (2), electric three-way valve (4), standard gas cylinder (7), vacuum pump (8), mass flow meter (11) and chromatographic injection port (14) constitute a high-precision quantitative injection system. The system extracts the sample to be tested from the gas storage tank (9) through the vacuum pump (8), controls the injection flow rate through the mass flow meter (11), and sends it to the gas chromatograph. The controller (12) is equipped with an interface for communication with the chromatography host, which is used for automatic sample injection and synchronous control of chromatography. The controller (12) forms feedback control with each system through feedback signals, and realizes the working mode of sample injection and purging by controlling the opening and closing of different valves and the start and stop of pumps.

2. The automated gas chromatography sampler for detecting organic sulfides as described in claim 1, characterized in that: The purge gas cylinder (1) is filled with nitrogen gas. The purge gas cylinder (1), the electrically controlled valve (2) and the vent (13) form a pipeline purging system for purging and venting the entire sample injection device.

3. The automated gas chromatography sampler for detecting organic sulfides as described in claim 1, characterized in that: The vent (13) is made of stainless steel with a diameter of 1 / 8 inch. It is vented outdoors or into a fume hood along with the gas chromatograph vent tube.

4. The automated gas chromatographic sampler for detecting organic sulfides as described in claim 1, characterized in that: The gas sampling bag (3), electric three-way valve (4), gas sampling cylinder (5), pressure gauge (6), vacuum pump (8), gas storage tank (9) and electromagnetic stirrer (10) constitute a sample gas injection and storage system. The gas sampling bag (3) and gas sampling cylinder (5) are the samples to be tested brought back from the field. The samples to be tested are pumped into the gas storage tank (9) for storage by the vacuum pump (8).

5. The automated gas chromatography sampler for detecting organic sulfides as described in claim 4, characterized in that: The vacuum pump (8) is an oil-free diaphragm pressurizing pump with a PTFE gasket inside. Its pressurization range is 0 to 0.5 MPa and its vacuum degree is -81 kPa. It is equipped with signal input and output to transmit operating parameters to the controller (12) and the controller (12) controls the start and stop of the vacuum pump (8).

6. The automated gas chromatography sampler for detecting organic sulfides as described in claim 4, characterized in that: The gas storage tank (9) is equipped with electrically controlled valves (2) in both the front and rear pipelines. The gas storage tank (9) is equipped with a pressure gauge (6). The volume of the gas storage tank (9) is 1-2L. The outer shell is made of stainless steel and the inner wall is made of polytetrafluoroethylene.

7. The automated gas chromatographic sampler for detecting organic sulfides as described in claim 4, characterized in that: The electromagnetic stirrer (10) is used to mix the gas inside the gas storage tank (9) evenly. Its impeller and blades are wrapped with polytetrafluoroethylene material. The impeller and blades contain magnets. The speed of the impeller is controlled by the electromagnetic stirrer (10) to be 0-5000 RPM. The electromagnetic stirrer (10) is equipped with signal input and output to transmit the operating parameters to the controller (12). The controller (12) controls the start and stop of the electromagnetic stirrer (10) and the operating parameters.

8. A method for automated gas chromatography injection for the detection of organic sulfides, implemented based on the automated gas chromatography injection device for the detection of organic sulfides according to any one of claims 1-7, characterized in that, Includes the following steps: S1: Open the automatic sampling device: The device automatically enters the self-test state and performs a self-test on all device valves in the system. After the self-test passes, the system prompts to connect the gas sampling bag (3) / gas sampling cylinder (5); if the self-test fails, it prompts that the self-test has failed and the instrument should be repaired. After repair, repeat S1. S2: Connect the sample: Connect to different interfaces depending on the sample. If it is a gas sampling bag (3), connect to the electric three-way valve (4) at the interface of the gas sampling bag (3). If it is a gas sampling cylinder (5), connect to the electric three-way valve (4) at the interface of the gas sampling cylinder (5). After connecting the sample, open the sealing valve of the gas sampling bag (3) / gas sampling cylinder (5). S3: After the sample is connected, the system automatically determines whether the sample connection is airtight. If a leak is detected, it will indicate that the sample is not connected properly. Please reconnect the sample and repeat S2. If the test passes, proceed to the next stage. S4: After S3 is completed, select the purging mode in the controller (12) and set the corresponding purging time; after setting, the system will automatically enter the purging mode and stop purging automatically after the set purging time is reached; S5: After the purging is completed, a prompt will appear asking whether to enter the sample injection state. If yes is selected, the system will automatically enter the sample injection state; if no is selected, the system will enter the stop state and end the sample injection. S6: When the system enters the sample injection state and then exits the sample injection state, the system prompts you to select the injection mode, which is gas bag mode, gas cylinder mode, or standard gas mode. S7: If the standard gas mode is selected, the system will enter the standard gas mode and start the standard gas injection. After one injection is completed, the system will prompt whether to continue to stop the injection. Choose according to the chromatographic requirements. If you choose no, the system will return to the standard gas injection state and continue the injection. If yes is selected, the system will enter a stopped state and the standard gas injection will end; S8: If the gas bag mode is selected, the system will automatically enter the gas bag mode; if the gas cylinder mode is selected, the system will automatically enter the gas cylinder mode. At this time, the system will prompt whether to start pre-injection. If yes is selected, the system will enter the pre-injection state; if no is selected, the system will enter the stop state and end the injection. S9: After the pre-injection state is completed, the system prompts whether to inject the sample. If you select yes, the system will enter the injection state. After one injection is completed, the system will automatically enter the pause injection state. If you select no, the system will directly enter the pause injection state. S10: When entering the pause injection state, the system prompts whether to continue injection. You need to judge according to the actual situation. If you need to continue injection, the system will return to the injection state and continue injection. If you choose no, the system will return to the purge state. The default purge time is 5 minutes. After the purge is completed, return to S5.

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