Online monitoring analyzer and monitoring method for trace chlorine content in hydrogen

Abstract

The invention belongs to the field of gas impurity on-line monitoring, and particularly relates to an on-line monitoring analyzer and monitoring method for trace chlorine content in hydrogen, and the whole system is composed of an absorption unit, an automatic standard solution preparation and sample introduction unit, an analysis unit and a central control platform. Specific trace ions in hydrogen are mainly absorbed through an absorption unit filled with specific absorption liquid, an absorbed sample is conveyed into a detection system and is analyzed and processed by the detection system, and then detection data are remotely transmitted to a central control platform.

Description

Technical Field

[0001] This application belongs to the field of online monitoring of gaseous impurities, specifically relating to an online monitoring and analysis instrument and method for trace chlorine content in hydrogen. Background Technology

[0002] The presence of chlorine in hydrogen, leading to high levels of chlorine condensation during hydrogenation, is a common problem faced by enterprises. Although hydrogen undergoes dechlorination treatment, HCl cannot be completely removed. When mixed with circulating hydrogen containing NH3, ammonium chloride condensation can form when flowing through heat exchangers, posing a corrosion risk to the equipment. Currently, the common method for detecting chloride ions in hydrogen is to collect hydrogen gas on-site using gas cylinders and then bring it back to the laboratory for analysis. The biggest problem with this method is that it is time-consuming, labor-intensive, and inefficient, failing to provide real-time concentration data and exhibiting data delays. Existing online detection technologies, such as online hydrogen chloride gas sensors based on electrochemical principles and online hydrogen chloride analyzers based on optical principles, are susceptible to interference from large amounts of hydrogen gas, resulting in low accuracy. Furthermore, optical methods require multiple light reflections to ensure accuracy, thus failing to meet explosion-proof requirements. In summary, due to the large fluctuations in chlorine content in hydrogen, the low frequency of routine offline sampling and detection, or the low precision of analytical methods, it is impossible to promptly grasp changes in chlorine content, detect high-risk opportunities, and make timely adjustments. To address this, this patent presents a novel system for the absorption and detection of trace amounts of chlorine in hydrogen, enabling online monitoring of chlorine content in high-purity hydrogen. This solves the problems of difficult offline sampling and inaccurate data, thereby accurately predicting the risks of salt deposition and corrosion in hydrogenation devices. Summary of the Invention

[0003] The method and system involved in this patent are mainly used for real-time and accurate online measurement of trace amounts of chlorine in high-purity hydrogen, solving the problems of difficult sampling and inaccurate data in offline detection. The technical solution is as follows:

[0004] An online monitoring and analysis instrument for trace chlorine content in hydrogen includes an absorption unit, an automatic standard solution preparation and injection unit, and an analysis unit;

[0005] The absorption unit absorbs specific trace ions in hydrogen gas.

[0006] Automatic standard solution preparation and injection unit: The absorbed liquid sample is delivered to the quantitative loop using an injection pump and injection tubing;

[0007] Analysis unit: Detection and analysis, automatic generation of calibration curves.

[0008] Preferably, the absorption unit includes a pressure reducing valve, a solenoid valve, a mass flow meter, a gas absorption bottle, and a waste liquid tank; one end of the pressure reducing valve is connected to the main pipeline, and the other end is connected to the mass flow meter through the solenoid valve, and the mass flow meter is connected to the gas absorption bottle; the bottom of the gas absorption bottle is connected to the waste liquid tank through a peristaltic pump; ultrapure water and absorbent are injected into the gas absorption bottle through a peristaltic pump and an injection pump, respectively.

[0009] Preferably, 30 mmol / L NaOH or KOH is used as the absorbent for chlorine in hydrogen; the solenoid valve is silanized.

[0010] Preferably, the gas absorption bottle is made of PFA soluble polytetrafluoroethylene, and a diffuser ball is added to the lower end of the inlet pipe. The volume of the diffuser ball is 1.8-3 cubic centimeters, the volume of the absorption bottle is 100 ml, and the ventilation rate is between 1 L / min and 10 L / min.

[0011] Preferably, the automatic standard solution preparation and injection unit includes a solenoid 10-way valve and a solenoid 6-way valve; the metering loop is connected to the injection valve position of the solenoid 6-way valve, and the injection valve positions of the solenoid 6-way valve are connected in pairs. After the sample passes through the metering loop in excess, the solenoid 6-way valve switches to standby mode; a solenoid 10-way valve is provided between the injection pump and the mass flow meter. When calibrating the standard sample, the standard solution is controlled by the central control platform to enter the solenoid 10-way valve, and then transported to the metering loop of the 6-way injection valve under the action of the injection pump.

[0012] Preferably, the analysis unit includes an eluent generator, a horizontal flow pump, a guard column, a column oven, a suppressor, and a conductivity detector. The eluent generator and the guard column are respectively connected to a solenoid six-way valve. The eluent generator is connected to the horizontal flow pump, through which ultrapure water enters the eluent generator. The guard column is connected to an anion exchange column. Chloride ions are separated by the anion exchange column and enter the suppressor. The suppressor is a self-regenerating electrolytic micromembrane suppressor, which uses electrolysis technology to generate the necessary H+ for suppression online. + or OH - The sample enters the conductivity cell of the conductivity detector. The conductivity cell quantifies chloride ions by detecting changes in conductivity within the cell, and simultaneously converts the electrical signal into a digital signal, which is then transmitted to the central control platform.

[0013] Preferably, the data from the analysis unit is transmitted to the IoT remote data transmission device via the MODBUS protocol, using 4G, WIFI, or wired network connection, and then transmitted to the cloud platform.

[0014] A method for online monitoring of trace chlorine content in hydrogen gas includes the following steps:

[0015] Open the main pipeline pressure reducing valve and adjust the main pipeline gas pressure to within the maximum withstand pressure of the mass flow meter. Set the time interval in the workstation to automatically run the sample sequence. Upon receiving the trigger signal from the workstation, the absorption unit starts the peristaltic pump to deliver ultrapure water to the gas absorption bottle for cleaning. The resulting waste liquid is transported to the waste liquid tank by the peristaltic pump to remove residual impurities. After cleaning, the syringe pump delivers 30 mmol / L NaOH or KOH absorbent solution to the gas absorption bottle through the infusion tube and diffuser. The absorbent volume is set and controlled in the workstation according to the detection requirements. After the absorbent solution is added, open the solenoid valve. The gas sample is absorbed through the absorbent solution. The workstation controls the opening and closing of the solenoid valve to adjust the instantaneous gas flow rate required for detection. The mass flow meter records the absorbed gas volume in real time, which is set by the workstation according to the detection requirements. After absorption, the solenoid valve closes, and the mass flow meter transmits the absorption process data to the workstation.

[0016] The absorbed liquid then enters the automated standard solution preparation and injection unit. The injection pump and injection tubing in the autosampler deliver the absorbed liquid sample to the quantitative loop of the solenoid six-way valve. Upon receiving a trigger signal from the autosampler, it switches from standby to injection mode. The quantitative loop is connected to the injection valve position of the solenoid six-way valve, and the injection valve positions of the solenoid six-way valve are interconnected. After an excess of sample passes through the quantitative loop, the solenoid six-way valve switches back to standby mode. The solenoid ten-way valve then transports the absorbed liquid sample or standard solution to the quantitative loop of the six-way injection valve under the action of the injection pump, completing the injection operation, and then proceeds to the next analysis unit.

[0017] The eluent generator in the analytical unit produces the required concentration of eluent through water electrolysis. The eluent carries the analyte chloride forward via a six-way injection valve to the guard column, and then into the anion exchange column in the column oven. The column oven provides a constant temperature environment for the stable operation of the anion exchange column. Chloride ions, after separation by the anion exchange column, enter the suppressor. The suppressor is a self-regenerating electrolytic micromembrane suppressor, which uses electrolysis technology to generate the necessary H+ for suppression online. + or OH - No acid or alkali is required for regeneration; the suppressor can reduce background conductivity and improve signal response value. Finally, the sample enters the conductivity cell of the conductivity detector. The conductivity cell quantifies chloride ions by detecting changes in conductivity within the cell and converts the electrical signal into a digital signal, which is then transmitted to the central control platform to form the final sample data.

[0018] Preferably, during standard sample calibration, the standard solution is controlled by the central control platform to enter the electromagnetic ten-way valve, and then transported to the quantitative loop of the six-way injection valve by the action of the injection pump, and enters the analysis unit. The system automatically generates a calibration curve of 6 points.

[0019] Preferably, a 15 mmol hydroxide system is used as the anion eluent, and the preparation method is as follows: First, saturated potassium hydroxide is stored in the eluent generator, and ultrapure water is introduced to generate hydrogen ions and hydroxide ions through online electrolysis. The magnitude of the current required for electrolysis can be controlled to obtain the required 15 mmol hydroxide system eluent. At the same time, gradient elution is performed by vacuum degassing to remove dissolved gases in the eluent, ensuring a degassing efficiency of over 80% and reducing the impact of bubbles on baseline noise.

[0020] Compared with the prior art, the beneficial effects of this application are as follows:

[0021] 1. An innovative online detection method for trace chlorine in hydrogen gas, with a detection limit ≤0.1 mg / L;

[0022] 2. The design of the high-efficiency absorption process and equipment route for trace chlorine in hydrogen ensures an absorption rate of over 95%, minimizes sample residue interference, and guarantees data accuracy.

[0023] 3. The design of the in-situ, timely, and highly sensitive detection module, including the eluent system and concentration, the degassing scheme of the eluent generator, the temperature of the column oven, and the selection of detectors, ensures the accuracy and timeliness of the data. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the present application;

[0025] Figure 2 This is a measurement graph showing the results when the concentrations of the standard solution are different.

[0026] In the diagram, 1-pressure reducing valve, 2-solenoid valve, 3-mass flow meter, 4-gas absorption bottle, 5-peristaltic pump, 6-waste tank, 7-injection pump, 8-solenoid 10-way valve, 9-solenoid 6-way valve, 10-elution fluid generator, 11-parallel flow pump, 12-guard column, 13-anion analysis column, 14-suppressor, 15-conductivity detector. Detailed Implementation

[0027] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0028] An online monitoring and analysis instrument for trace chlorine content in hydrogen includes an absorption unit, an automatic standard solution preparation and injection unit, and an analysis unit;

[0029] The absorption unit absorbs specific trace ions in hydrogen gas.

[0030] Automatic standard solution preparation and injection unit: The absorbed liquid sample is delivered to the quantitative loop using an injection pump and injection tubing;

[0031] Analysis unit: Detection and analysis, automatic generation of calibration curves.

[0032] The absorption unit includes a pressure reducing valve 1, a solenoid valve 2, a mass flow meter 3, a gas absorption bottle 4, and a waste liquid tank 6. One end of the pressure reducing valve 1 is connected to the main pipeline, and the other end is connected to the mass flow meter 3 through the solenoid valve 2. The mass flow meter 3 is connected to the gas absorption bottle 4. The bottom of the gas absorption bottle 4 is connected to the waste liquid tank 6 through a peristaltic pump 5. Ultrapure water and absorption liquid are injected into the gas absorption bottle 4 through the peristaltic pump 5 and the injection pump 7, respectively.

[0033] The automatic standard solution preparation and injection unit includes a solenoid 10-way valve 8 and a solenoid 6-way valve 9. The metering loop of the solenoid 6-way valve 9 is connected to its injection valve position, and the injection valve positions of the solenoid 6-way valve 9 are connected in pairs. After the sample passes through the metering loop in excess, the solenoid 6-way valve 9 switches to standby mode. A solenoid 10-way valve 8 is provided between the syringe pump 7 and the mass flow meter 3. When calibrating the standard sample, the standard solution is controlled by the central control platform to enter the solenoid 10-way valve 8, and then transported to the metering loop of the solenoid 6-way valve 9 under the action of the syringe pump 7.

[0034] The eluent generator 10 is connected to the horizontal flow pump 11, and ultrapure water enters the eluent generator 10 through the horizontal flow pump 11. The guard column 12 is connected to the anion analysis column 13, and chloride ions enter the suppressor 14 after separation by the anion separation column 13. The suppressor 14 is a self-regenerating electrolytic micromembrane suppressor, which uses electrolysis technology to generate the H+ required for suppression online. + or OH - The sample enters the conductivity cell of the conductivity detector 15. The conductivity cell quantifies chloride ions by detecting changes in conductivity within the cell and simultaneously converts the electrical signal into a digital signal, which is then transmitted to the central control platform.

[0035] This patented invention discloses a novel hydrogen trace chlorine absorption and detection analyzer, enabling online monitoring of trace chlorine content in high-purity hydrogen and solving the problems of difficult sampling and inaccurate data in offline detection. The entire system consists of an absorption unit, an automatic standard solution preparation and injection unit, an analysis unit, a central control platform, and an explosion-proof enclosure. It primarily uses an absorption unit containing a specific absorbent to absorb specific trace ions in hydrogen, and then delivers the absorbed sample into the detection system. After analysis and processing by the detection system, the detection data is remotely transmitted to the central control platform. The detection limit for trace chlorine in hydrogen using this system is ≤0.1 mg / L.

[0036] The absorption unit mainly performs sampling and absorption operations, as shown in the attached diagram. Figure 1 As shown in the figure. A 30 mmol / L solution (NaOH or KOH) was used as the absorbent for chlorine in hydrogen. Two solenoid valves underwent silanization treatment. The gas pipeline material was PTFE (Teflon). Gas absorption bottle 4 was made of PFA (soluble polytetrafluoroethylene). A diffuser ball with a volume of 1.8-3 cubic centimeters was added to the lower end of the inlet pipe of the gas absorption bottle. The absorption bottle volume was 100 ml, and the ventilation rate was between 1 L / min and 10 L / min. During measurement, first, open the main pipeline pressure reducing valve and adjust the main pipeline gas pressure to within the maximum withstand pressure of the mass flow meter (generally 0.5 MPa). Set the time interval in the workstation to automatically run the sample sequence. Upon receiving the trigger signal from the workstation, the peristaltic pump 5 starts delivering ultrapure water to the gas absorption bottle 4 for cleaning. The resulting waste liquid is transported to the waste liquid tank 6 by the peristaltic pump 5 to remove residual impurities. After cleaning, the syringe pump 7 delivers 30 mmol / L (NaOH or KOH) absorption liquid to the gas absorption bottle 4 through the infusion tube and diffuser. The volume of the absorption liquid is set and controlled in the workstation according to the detection requirements. After the absorption liquid is added, open the solenoid valve 2. The gas sample is fully absorbed by the absorption liquid. The workstation controls the opening and closing of the solenoid valve 2 to adjust the instantaneous gas flow rate required for detection. The mass flow meter 3 records the volume of absorbed gas in real time, and the volume of absorbed gas is set by the workstation according to the detection requirements.

[0037] After absorption is complete, solenoid valve 2 closes, and mass flow meter 3 transmits the absorption process data to the workstation. The absorbed liquid then enters the automatic standard solution preparation and injection unit. The injection pump 7 and injection tubing in the autosampler deliver the absorbed liquid sample to the metering loop of the solenoid six-way valve 9. Upon receiving the trigger signal from the autosampler, the system switches from the initial standby state to the injection state. The metering loop can be selected from 25μL, 50μL, and 100μL sizes, depending on the ion concentration in the sample. The metering loop is connected to the injection valve position of the solenoid six-way valve 9, and the injection valve positions of the solenoid six-way valve 9 are interconnected. After the sample passes through the metering loop in excess, the solenoid six-way valve 9 switches to the standby state.

[0038] During standard sample calibration, the standard solution is controlled by the central control platform to enter the electromagnetic 10-way valve 8, and then transported to the quantitative loop of the electromagnetic 6-way valve 9 by the syringe pump 7, entering the analysis unit. The system automatically generates a calibration curve at 6 points. This unit has a low-temperature storage function, which can provide a shelf life of 1 month for the standard solution, ensuring long-term operation.

[0039] The electromagnetic 10-way valve 8 transports the absorbed liquid sample or standard solution to the quantitative loop of the electromagnetic 6-way valve 9 under the action of the syringe pump, completing the injection operation. The sample then proceeds to the next analytical unit, allowing the absorbed liquid sample to enter the anion exchange column for separation under the delivery of the eluent. The analytical unit includes an eluent generator 10, a horizontal flow pump 11, a column oven, a suppressor 14, and a conductivity detector 15. The eluent generator 10 generates the required concentration of eluent by electrolyzing water, using a 15 mmol hydroxide system as the anion eluent. The eluent generator 10 initially stores saturated potassium hydroxide. Hydrogen ions and hydroxide ions are generated online through the introduction of ultrapure water via electrolysis. The required current for electrolysis can be controlled to obtain the desired 15 mmol hydroxide system eluent. Simultaneously, gradient elution is performed using vacuum degassing to remove dissolved gases from the eluent, ensuring a degassing efficiency of over 80% and reducing the impact of bubbles on baseline noise. The eluent carries the chlorine ions to be analyzed forward through the electromagnetic six-way valve 9 to the guard column 12. The guard column 12 ensures that the anion separation column is protected from contamination by organic matter, heavy metals, etc. in the sample. It then enters the anion separation column 13 in the column oven, which provides a constant temperature environment for the anion separation column to function stably. The column oven temperature is 35℃, using a contact heating mode, and the programmed temperature rise is controlled by the central control platform. Chlorine ions, after separation by the anion separation column 13, enter the suppressor 14. The suppressor 14 is a self-regenerating electrolytic micromembrane suppressor, using electrolysis technology to generate the necessary H+ for suppression online. + or OH - No acid or alkali is required for regeneration. The suppressor reduces background conductivity and improves signal response. The final sample enters the conductivity cell of the conductivity detector 15. The conductivity cell quantifies chloride ions by detecting changes in conductivity within the cell, and simultaneously converts the electrical signal into a digital signal, which is then transmitted to the central control platform to form the final sample data. Data can be transmitted to IoT remote data transmission devices via the MODBUS protocol, or via network connection using 4G, Wi-Fi, or Ethernet cables to transmit data to the cloud platform.

[0040] During testing, the explosion-proof enclosure must be connected to a dry and clean compressed air source (pressure 0.6-0.8 MPa, air volume 100-120 cubic meters / hour). To ensure the normal operation of the instruments inside the explosion-proof device, the main electrical equipment in the enclosure includes: explosion-proof air conditioning; explosion-proof electrical control box; explosion-proof lighting fixtures; explosion-proof gas detector electrical equipment; and positive pressure ventilation duct components, with an explosion-proof rating of Ex(d)ⅡC T2 or higher, to ensure the safe and effective conduct of on-site analysis and testing.

[0041] Through the design of the above detection unit and the setting of process conditions, the linearity reached above 0.999 when the standard solution concentrations were 0.1 mg / L, 0.2 mg / L, 0.3 mg / L, 0.4 mg / L, and 0.5 mg / L. The measured chloride ion concentration in the sample reached 0.0032 mg / L, which translates to 0.0025 μmol / mol in the gas, achieving accurate online real-time measurement of trace chlorine in hydrogen gas.

[0042] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), memory bus DRAM (RDRAM), and interface DRAM (DRDRAM), etc.

[0043] In the description of this specification, references to terms such as "some embodiments," "other embodiments," and "ideal embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0044] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. An online monitoring and analysis instrument for trace chlorine content in hydrogen gas, characterized in that, Includes an absorption unit, an automated standard solution preparation and injection unit, and an analysis unit; The absorption unit absorbs specific trace ions in hydrogen gas. Automatic standard solution preparation and injection unit: The absorbed liquid sample is delivered to the quantitative loop using an injection pump and injection tubing; Analysis unit: Detection and analysis, automatic generation of calibration curves.

2. The online monitoring and analysis instrument for trace chlorine content in hydrogen according to claim 1, characterized in that, The absorption unit includes a pressure reducing valve, a solenoid valve, a mass flow meter, a gas absorption bottle, and a waste liquid tank. One end of the pressure reducing valve is connected to the main pipeline, and the other end is connected to the mass flow meter via the solenoid valve. The mass flow meter is connected to the gas absorption bottle. The bottom of the gas absorption bottle is connected to the waste liquid tank via a peristaltic pump. Ultrapure water and absorbent are injected into the gas absorption bottle via a peristaltic pump and a syringe pump, respectively.

3. The on-line monitoring analyzer for trace chlorine content in hydrogen gas according to claim 2, characterized in that, 30 mmol / L NaOH or KOH was used as the absorbent for chlorine in hydrogen gas; the solenoid valve was silanized.

4. The online monitoring and analysis instrument for trace chlorine content in hydrogen according to claim 2, characterized in that, The gas absorption bottle is made of PFA soluble polytetrafluoroethylene. A diffuser ball is added to the lower end of the inlet pipe. The volume of the diffuser ball is 1.8-3 cubic centimeters. The volume of the absorption bottle is 100 ml, and the ventilation rate is between 1 L / min and 10 L / min.

5. The online monitoring and analysis instrument for trace chlorine content in hydrogen according to claim 1, characterized in that, The automatic standard solution preparation and injection unit includes a solenoid 10-way valve and a solenoid 6-way valve. The metering loop is connected to the injection valve position of the solenoid 6-way valve, and the injection valve positions of the solenoid 6-way valve are connected in pairs. After the sample passes through the metering loop in excess, the solenoid 6-way valve switches to standby mode. A solenoid 10-way valve is installed between the injection pump and the mass flow meter. When calibrating the standard sample, the standard solution is controlled by the central control platform to enter the solenoid 10-way valve, and then transported to the metering loop of the 6-way injection valve under the action of the injection pump.

6. The online monitoring and analysis instrument for trace chlorine content in hydrogen according to claim 1, characterized in that, The analytical unit includes an eluent generator, a horizontal flow pump, a guard column, a column oven, a suppressor, and a conductivity detector. The eluent generator and guard column are connected to a solenoid six-way valve. The eluent generator is connected to the horizontal flow pump, through which ultrapure water enters the eluent generator. The guard column is connected to an anion exchange column. Chloride ions are separated by the anion exchange column and enter the suppressor, which is a self-regenerating electrolytic micromembrane suppressor that uses electrolysis technology to generate the necessary H+ for suppression online. + or OH - The sample enters the conductivity cell of the conductivity detector. The conductivity cell quantifies chloride ions by detecting changes in conductivity within the cell, and simultaneously converts the electrical signal into a digital signal, which is then transmitted to the central control platform.

7. The online monitoring and analysis instrument for trace chlorine content in hydrogen according to claim 1, characterized in that, The data from the analysis unit is transmitted to the IoT remote data transmission device via the MODBUS protocol, using 4G, WIFI, or wired network connection to transmit the data to the cloud platform.

8. A method for online monitoring of trace chlorine content in hydrogen gas, characterized in that, The online monitoring and analysis instrument according to any one of claims 1-7 includes the following steps: Open the main pipeline pressure reducing valve and adjust the main pipeline gas pressure to within the maximum withstand pressure of the mass flow meter. Set the time interval in the workstation to automatically run the sample sequence. Upon receiving the trigger signal from the workstation, the absorption unit starts the peristaltic pump to deliver ultrapure water to the gas absorption bottle for cleaning. The resulting waste liquid is transported to the waste liquid tank by the peristaltic pump to remove residual impurities. After cleaning, the syringe pump delivers 30 mmol / L NaOH or KOH absorbent solution to the gas absorption bottle through the infusion tube and diffuser. The absorbent volume is set and controlled in the workstation according to the detection requirements. After the absorbent solution is added, open the solenoid valve. The gas sample is absorbed through the absorbent solution. The workstation controls the opening and closing of the solenoid valve to adjust the instantaneous gas flow rate required for detection. The mass flow meter records the absorbed gas volume in real time, which is set by the workstation according to the detection requirements. After absorption, the solenoid valve closes, and the mass flow meter transmits the absorption process data to the workstation. The absorbed liquid then enters the automated standard solution preparation and injection unit. The injection pump and injection tubing in the autosampler deliver the absorbed liquid sample to the quantitative loop of the solenoid six-way valve. Upon receiving a trigger signal from the autosampler, it switches from standby to injection mode. The quantitative loop is connected to the injection valve position of the solenoid six-way valve, and the injection valve positions of the solenoid six-way valve are interconnected. After an excess of sample passes through the quantitative loop, the solenoid six-way valve switches back to standby mode. The solenoid ten-way valve then transports the absorbed liquid sample or standard solution to the quantitative loop of the six-way injection valve under the action of the injection pump, completing the injection operation, and then proceeds to the next analysis unit. The eluent generator in the analytical unit produces the required concentration of eluent through water electrolysis. The eluent, carrying the chlorine ions to be analyzed, is transported forward to the guard column via a solenoid six-way valve, and then enters the anion exchange column in the column oven. The column oven provides a constant temperature environment for the stable operation of the anion exchange column. Chlorine ions, after separation by the anion exchange column, enter the suppressor. The suppressor is a self-regenerating electrolytic micromembrane suppressor, which uses electrolysis technology to generate the necessary H+ for suppression online. + or OH - No acid or alkali is required for regeneration; the suppressor can reduce background conductivity and improve signal response value. Finally, the sample enters the conductivity cell of the conductivity detector. The conductivity cell quantifies chloride ions by detecting changes in conductivity within the cell and converts the electrical signal into a digital signal, which is then transmitted to the central control platform to form the final sample data.

9. The monitoring method according to claim 8, characterized in that, During standard sample calibration, the standard solution is controlled by the central control platform to enter the electromagnetic ten-way valve, and then transported to the quantitative loop of the six-way injection valve by the action of the injection pump, and enters the analysis unit. The system automatically generates a calibration curve for 6 points.

10. The monitoring method according to claim 8, characterized in that, The 15 mmol hydroxide system was used as the anion eluent, and the preparation method is as follows: First, saturated potassium hydroxide is stored in the eluent generator. Ultrapure water is introduced and hydrogen ions and hydroxide ions are generated through online electrolysis. The magnitude of the current required for electrolysis can be controlled to obtain the required 15 mmol hydroxide system eluent. At the same time, gradient elution is performed by vacuum degassing to remove dissolved gases from the eluent, ensuring a degassing efficiency of over 80% and reducing the impact of bubbles on baseline noise.

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