Method and system for monitoring anions and cations in underground thermal spring water

Abstract

The invention discloses a monitoring method and system for anions and cations in underground thermal spring water. The monitoring system comprises a sampling flow path, a sample injection flow path and a detection flow path. The sampling flow path comprises a water sampling pipeline, a grit chamber, a sample cup and a sampling tank, the sample injection flow path comprises a sample injection pipeline, an injection pump, a metering unit and a multi-way valve, and the detection flow path comprises a detection pipeline, a protection column, an analysis column and a suppressor. According to the monitoring method and system, manual sampling is not needed, analysis of the to-be-detected water sample, the standard sample, the quality control sample and the blank sample and the cleaning process of the pipeline are automatically achieved, and on-site continuous monitoring is facilitated. The whole monitoring system is simple in operation process and high in automation degree, reduces the consumption of manpower and material resources, saves the sample pretreatment time and tedious operation process, and is high in system stability and accuracy.

Description

Technical Field

[0001] The present invention relates to an ion chromatography detection technology, and particularly to a method and system for monitoring cations and anions in underground hot spring water. Background Art

[0002] As a kind of underground fluid, hot springs are mostly distributed along fault zones, carrying a large amount of geochemical information from the deep crust. They can carry information such as the migration, differentiation, and evolution of elements and isotopes in deep crustal fluids to the surface. Because of the sensitivity of their abnormal chemical and isotope compositions to the dynamic process of earthquake gestation, they have attracted much attention and have become a hot measurement item for earthquake precursor monitoring. The earthquake monitoring and prediction task of underground fluids is to reveal the laws of strong earthquake gestation, occurrence, and tectonic activities and the mechanism of fluid anomalies based on the observation products of shallow and deep fluid dynamics, establish an earthquake prediction and forecasting method with a physical basis, and provide scientific support for earthquake trend determination, earthquake situation tracking, fault activity, and anomaly verification. Earthquake precursor anomalies in hot springs mainly include hydrophysical anomalies and hydrochemical anomalies. Hydrophysical anomalies mainly consist of water temperature, water level, and flow rate, etc., while hydrochemistry mainly consists of ionic components, gas components, and isotopes, etc. Macroscopic anomalies are also commonly seen in turbid spring water, bubbling, etc. The ionic concentration anomalies in hot spring water, such as F - concentration, Cl - concentration, SO4 2- concentration, Na + concentration, K + concentration, Ca 2+ concentration, etc., have certain earthquake prediction significance and many application examples.

[0003] In previous work, researchers manually collected hot spring water samples and then sent them to relevant institutions for testing. Samples were usually collected only once or repeated after a long interval. The data obtained could only reflect the hydrogeological information at the sampling moment and could not continuously obtain the dynamic change data of the chemical and isotope compositions of hot spring water, which had certain limitations for accurately predicting earthquakes. In fact, the earth is active. During the earthquake gestation and occurrence process, the loading and unloading of crustal stress induce water mixing, dissolution of volatile components, and water-rock reactions, etc., making the chemical and isotope compositions of hot spring water show an increase or decrease change deviating from the non-seismic period fluctuations. Identifying the response law of this change to earthquakes will provide a more reliable theoretical basis for judging the earthquake situation based on continuous observation of hot spring water chemistry. Summary of the Invention

[0004] In order to solve the above deficiencies in the prior art, the purpose of the present invention is to provide a method and system for monitoring cations and anions in underground hot spring water.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows: A method for monitoring cations and anions in underground hot spring water includes the following steps

[0006] Baseline acquisition: Continuously transport the eluent to the ion chromatography detection system to make the ion chromatography system reach an equilibrium state. The baseline signal value of the eluent is detected by a conductivity detector and collected and recorded by the host computer software.

[0007] Sample pretreatment: Collect the underground hot spring water into the sand settling tank. After the underground hot spring water cools and stands in the sand settling tank for a period of time, transport the underground hot spring water into the sample cup, and then transport the underground hot spring water from the sample cup to the sampling tank.

[0008] Collection of anions and cations in underground hot spring water: Transport the underground hot spring water to the metering unit of the first six-way valve.

[0009] Analysis of underground hot spring water: By switching the states of the multi-way valve and the first six-way valve, transport the underground hot spring water in the metering unit to the guard column, analytical column, and suppressor. Detect the chromatographic data by a conductivity detector, and obtain and analyze the chromatographic data in the host computer software.

[0010] Upload monitoring data to the cloud platform: Process and analyze the chromatographic data by the host computer software, and upload the monitoring factor information to the cloud platform.

[0011] In addition, based on the above monitoring method, the present invention also proposes a monitoring system for anions and cations in underground hot spring water, which includes a sampling flow path, an injection flow path, and a detection flow path.

[0012] Among them, the sampling flow path includes a water sampling pipeline, a sand settling tank, a sample cup, and a sampling tank. When sampling the underground hot spring water, first collect it into the sand settling tank. After the underground hot spring water cools and stands in the sand settling tank for a period of time, transport the underground hot spring water into the sample cup, and then transport the underground hot spring water from the sample cup to the sampling tank.

[0013] The injection flow path includes an injection pipeline, an injection pump, a metering unit, and a multi-way valve. When collecting anions and cations in underground hot spring water, transport the underground hot spring water to the metering unit of the first six-way valve, and through the switching of the states of the multi-way valve and the first six-way valve, transport the underground hot spring water in the metering unit to the detection flow path.

[0014] The detection flow path includes a detection pipeline, a guard column, an analytical column, and a suppressor. When analyzing the underground hot spring water, the underground hot spring water flows through the guard column, analytical column, and suppressor in sequence, detects the chromatographic data by a conductivity detector, and obtains and analyzes the chromatographic data in the host computer software.

[0015] With the above technical solution, the monitoring method and system of the present invention do not require manual sampling, and can automatically realize the analysis of water samples to be measured, standard samples, quality control samples, blank samples, and the cleaning process of pipelines, which is conducive to on-site continuous monitoring. The operation process of the entire monitoring system is simple, with a high degree of automation, reducing the consumption of manpower and material resources, saving the time for sample pretreatment and the cumbersome operation process. At the same time, the system has high stability and high accuracy. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of the flow path system of the present invention;

[0017] Figure 2 is a schematic diagram of the anion detection flow path of the present invention;

[0018] Figure 3 is a schematic diagram of the cation detection flow path of the present invention;

[0019] Figure 4 is the chromatogram of the anion standard solution;

[0020] Figure 5 is the chromatogram of the cation standard solution;

[0021] Figure 6 is the anion chromatogram in the underground hot spring water sample;

[0022] Figure 7 is the cation chromatogram in the underground hot spring water sample. Detailed Embodiments

[0023] The following further elaborates on the present application in conjunction with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than limiting the invention. Additionally, it should be noted that for ease of description, only the parts related to the invention are shown in the drawings.

[0024] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The following will elaborate on the present application in detail with reference to the drawings and embodiments.

[0025] The present invention discloses a monitoring system for anions and cations in underground hot spring water. This monitoring system is a system for real-time monitoring of the content of conventional anions and cations in underground hot spring water. The monitoring data can capture the precursor changes in the corresponding ion content before an earthquake, and the monitoring data is mainly used for pre-earthquake analysis and research, and post-earthquake trend judgment.

[0026] Specifically, the monitoring system includes a sampling flow path, an injection flow path, and a detection flow path.

[0027] Such as Figure 1As shown, the sampling flow path includes a water sampling pipeline, a sand settling tank 1, a sample cup 2, and a sampling tank 3. When sampling underground hot spring water, it is first collected into the sand settling tank 1. After the underground hot spring water cools and stands in the sand settling tank 1 for a period of time, the underground hot spring water is then transported into the sample cup 2, and then the underground hot spring water is transported from the sample cup 2 into the sampling tank 3.

[0028] During this process, the underground hot spring water can be pumped into the sampling tank 3 after passing through two - stage filtration. Among them, the first - stage filter 4 is connected to the pipeline in front of the sample cup 2. The filter element material of the first - stage filter 4 can use a PP fiber membrane or a PVDF fiber membrane, which can filter out large - particle impurities, such as sulfur. The second - stage filter 5 is connected to the pipeline between the sample cup 2 and the sampling tank 3. The filter element of the second - stage filter 5 can use a PTFE membrane, which can perform fine filtration on the underground hot spring water, enabling the ions to be measured to pass through the second - stage filter 5.

[0029] In the present invention, the collection of underground hot spring water is pumped through various pumps. For example, when collecting underground hot spring water, the underground hot spring water can be pumped into the water sampling pipeline by a self - priming pump 6. After being treated by the sand settling tank 1, the underground hot spring water is then pumped into the sample cup 2 by a diaphragm pump, and then the underground hot spring water is sent into the sampling tank 3 by a peristaltic pump 7. Through the use of each pump, the underground hot spring water can be accurately and quantitatively transported into the sampling tank 3 for storage. In the present invention, since there is a second - stage filter 5 between the sampling tank 3 and the sample cup 2, the number of peristaltic pumps 7 can be set to two. The two peristaltic pumps 7 are respectively arranged at both ends of the second - stage filter 5 to improve the filtration efficiency. In addition, the number of second - stage filters 5 can also be set to multiple, such as 2. Multiple second - stage filters 5 are arranged in parallel for alternative use.

[0030] As Figure 1 shown, the sample injection flow path includes a sample injection pipeline, an injection pump 8, a metering unit 9, and a multi - way valve 10. The metering unit 9 and the injection pump 8 are connected in the first six - way valve 11. The first six - way valve 11 is connected to one of the interfaces of the metering unit 9 and the multi - way valve 10. In addition, the first six - way valve 11 is also connected to ultrapure water or a zero sample for flushing or rinsing the first six - way valve 11. When collecting cations and anions in the underground hot spring water, the underground hot spring water is first transported into the metering unit 9 of the first six - way valve 11, and through the switching of the multi - way valve 10, the underground hot spring water in the metering unit 9 is transported into the detection flow path.

[0031] In the present invention, the metering unit 9 can use, for example, a quantitative loop to quantitatively send the underground hot spring water for sampling. The injection pump 8 can use a plunger pump, and the multi - way valve 10 can use a ten - way valve.

[0032] As Figure 2 and Figure 3As shown, the detection flow path includes a detection pipeline, a guard column 12, an analytical column 13, and a suppressor 14. The detection flow path is divided into an anion detection flow path and a cation detection flow path. The anion detection flow path and the cation detection flow path are respectively connected to the interfaces of the multi-way valve 10, and the interfaces of the two are adjacent. Specifically, the anion detection flow path is connected to the multi-way valve 10 through the second six-way valve 15, and the cation detection flow path is connected to the multi-way valve 10 through the third six-way valve 16. When analyzing underground hot spring water, the underground hot spring water flows through the guard column 12, the analytical column 13, and the suppressor 14 in sequence, and the chromatographic data is detected by the conductivity detector 17, and the chromatographic data is obtained and analyzed in the upper computer software.

[0033] Based on the above monitoring system for anions and cations in underground hot spring water, the present invention provides a method for monitoring anions and cations in underground hot spring water, and its steps are as follows:

[0034] S1. Baseline acquisition.

[0035] The eluent is continuously transported to the ion chromatography detection system to make the ion chromatography system reach an equilibrium state. The baseline signal value of the eluent is detected by the conductivity detector 17 and collected and recorded by the upper computer software.

[0036] S2. Sample pretreatment.

[0037] The underground hot spring water is collected into the sand settling tank 1. After the underground hot spring water cools and stands in the sand settling tank 1 for a period of time, the underground hot spring water is transported into the sample cup 2, and then the underground hot spring water is transported from the sample cup 2 to the sampling tank 3.

[0038] S3. Collection of anions and cations in underground hot spring water.

[0039] The underground hot spring water is transported to the metering unit 9 of the first six-way valve 11.

[0040] S4. Analysis of underground hot spring water.

[0041] By switching the states of the multi-way valve 10 and the first six-way valve 11, the underground hot spring water in the metering unit 9 is transported to the guard column 12, the analytical column 13, and the suppressor 14, and the chromatographic data is detected by the conductivity detector 17, and the chromatographic data is obtained and analyzed in the upper computer software.

[0042] S5. Upload monitoring data to the cloud platform.

[0043] The chromatographic data is processed and analyzed by the upper computer software, and the monitoring factor information is uploaded to the cloud platform.

[0044] The following specifically describes the present invention through the technical solution of Example 1.

[0045] S10. Preparation of standard solution:

[0046] Prepare the required concentrations using the standard solutions (F-, Cl-, SO42-, Li+, Na+, K+, Mg2+, Ca2+) with a concentration of 1000 mg / L in the laboratory, and their concentrations are 5 mg / L, 300 mg / L, 100 mg / L, 0.2 mg / L, 300 mg / L, 20 mg / L, 50 mg / L, and 200 mg / L respectively, and place them in a refrigerated refrigerator. The automatic establishment of the calibration curve can be completed by means of partial injection.

[0047] S20. Eluent preparation:

[0048] Automatically prepare with an eluent generator, 15 mmol / L KOH and 30 mmol / L MSA.

[0049] S30. Pretreatment, collection, and injection analysis of samples:

[0050] The self-priming pump collects groundwater into the grit chamber 1 for static cooling, and then under the action of the diaphragm pump, the sample to be measured in the grit chamber 1 is transported to the sample cup 3 through the first-stage filter 4;

[0051] The solenoid valve 3 is in the NC state, the peristaltic pump 3 pumps pure water into the sampling tank. After the sampling tank is filled, the peristaltic pump 3 is turned off. The solenoid valve 4 is in the NC state, and the peristaltic pump 4 works to empty the sampling tank. This process is the cleaning of the sampling tank;

[0052] Both solenoid valves 1 and 2 are in the NC state, solenoid valve 3 is in the NO state, peristaltic pumps 1 and 2 work simultaneously to pump the sample to be measured in the front-end sample cup into the sampling tank after ultrafiltration. After the sampling tank is filled, peristaltic pumps 1 and 2 are turned off. The solenoid valve 4 is in the NC state, and the peristaltic pump 4 works to empty the sampling tank. This process is the rinsing of the sampling tank. Note: The use cycle of the ultrafiltration cell can be set by the states of solenoid valves 1 and 2 for automatic switching;

[0053] Both solenoid valves 1 and 2 are in the NC state, solenoid valve 3 is in the NO state, peristaltic pumps 1 and 2 work simultaneously to pump the sample to be measured in the front-end sample cup into the sampling tank after ultrafiltration and fill the sampling tank;

[0054] The 8th and 9th interfaces of the ten-port valve are connected to the second six-port valve and the third six-port valve respectively. The injection pump first injects ultrapure water into the quantitative loop of the second six-port valve, then switches the ten-port valve to the 10th interface to inject air into the quantitative loop of the second six-port valve, and finally switches the ten-port valve to the 1st interface to inject the sample to be measured into the quantitative loop of the second six-port valve to complete sample loading. This process can reduce the cross-contamination rate. Subsequently, after the position of the second six-port valve is switched, the sample is transported to the analytical column for separation and finally enters the conductivity detector for detection. The analysis process of cation components is the same as that of anion components and will not be elaborated here.

[0055] S40. Upload monitoring data to the cloud platform:

[0056] By pre-setting the processing method in the host computer software in advance, the monitoring data can be automatically uploaded to the cloud platform, and the data on the cloud platform can be remotely viewed and exported, including anion and cation concentrations, conductivity value, water temperature, ambient temperature and humidity, pH value of water sample, alarm information, etc.

[0057] Figure 4 It is the chromatogram of the anion standard solution. Peak 1 is F － , with a concentration of 5 mg / L; Peak 2 is Cl － , with a concentration of 300 mg / L; Peak 3 is SO4 2－ , with a concentration of 100 mg / L.

[0058] Figure 5 It is the chromatogram of the cation standard solution. Peak 1 is Li + , with a concentration of 0.2 mg / L; Peak 2 is Na + , with a concentration of 300 mg / L; Peak 3 is K + , with a concentration of 20 mg / L; Peak 4 is Mg 2+ , with a concentration of 50 mg / L; Peak 5 is Ca 2+ , with a concentration of 200 mg / L.

[0059] Figure 6 It is the anion chromatogram of the underground hot spring water sample. Peak 1 is F － , with a concentration of 0.843 mg / L; Peak 2 is Cl － , with a concentration of 166.656 mg / L; Peak 3 is SO4 2－ , with a concentration of 55.825 mg / L.

[0060] Figure 7 It is the cation chromatogram of the underground hot spring water sample. Peak 1 is Li + , with a concentration of 0.089 mg / L; Peak 2 is Na + , with a concentration of 153.355 mg / L; Peak 3 is K + , with a concentration of 7.706 mg / L; Peak 4 is Mg 2+ , with a concentration of 21.112 mg / L; Peak 5 is Ca 2+ , with a concentration of 135.340 mg / L.

[0061] The above description is only a preferred embodiment of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in the present application.

[0062] Except for the technical features described in the specification, the remaining technical features are well-known to those skilled in the art. To highlight the innovative features of the present invention, the remaining technical features are not described herein again.

Claims

1. A method for monitoring anions and cations in underground hot spring water, characterized in that: The following steps are included: Baseline acquisition: The eluent is continuously delivered to the ion chromatography detection system to allow the ion chromatography system to reach a balanced state. The baseline signal value of the eluent is detected by a conductivity detector and collected and recorded by the host computer software; Sample pretreatment: Collect underground hot spring water into a grit chamber, wait for the underground hot spring water to cool and stand for a period of time in the grit chamber, then transfer the underground hot spring water into a sample cup, and then transfer the underground hot spring water from the sample cup to a sampling tank; Collection of anions and cations in underground hot spring water: transporting underground hot spring water to the metering unit of the first six-way valve; Analysis of underground hot spring water: by switching the states of the multi-way valve and the first six-way valve, the underground hot spring water in the metering unit is transported to the protection column, analytical column and suppressor, the chromatographic data is detected by the conductivity detector, and the chromatographic data is obtained and analyzed in the upper computer software; Upload monitoring data to the cloud platform: Process and analyze chromatographic data through host computer software, and upload monitoring factor information to the cloud platform.

2. The method for monitoring anions and cations in underground hot spring water according to claim 1, characterized in that: In the sample pre-treatment step, the underground hot spring water enters the sampling tank after two-stage filtration, wherein the first-stage filter is arranged in the front-stage pipeline of the sample cup, and the second-stage filter is arranged between the sample cup and the sampling tank.

3. The method for monitoring anions and cations in underground hot spring water according to claim 2, characterized in that: The filter element material of the first-stage filter is PP fiber membrane or PVDF fiber membrane.

4. The method for monitoring anions and cations in underground hot spring water according to claim 2, characterized in that: The filter element material of the second-stage filter is PTFE membrane.

5. The method for monitoring anions and cations in underground hot spring water according to claim 4, characterized in that: There are at least two second-stage filters, which are connected in parallel in the pipeline.

6. A monitoring system for anions and cations in underground hot spring water, characterized in that: It includes a sampling flow path, an injection flow path and a detection flow path; The sampling flow path includes a water sampling pipeline, a grit chamber, a sample cup, and a sampling tank. When sampling underground hot spring water, the underground hot spring water is first collected in the grit chamber, and after the underground hot spring water is cooled and left to stand for a period of time in the grit chamber, the underground hot spring water is transported to the sample cup, and then the underground hot spring water is transported from the sample cup to the sampling tank; The sampling flow path includes a sampling pipeline, a syringe pump, a metering unit, and a multi-way valve. When collecting anions and cations in underground hot spring water, the underground hot spring water is transported to the metering unit of the first six-way valve, and the underground hot spring water in the metering unit is transported to the detection flow path by switching the multi-way valve and the first six-way valve. The detection flow path includes a detection pipeline and a protective column, an analytical column, and a suppressor. When analyzing underground hot spring water, the underground hot spring water flows through the protective column, the analytical column, and the suppressor in sequence, and the chromatographic data is detected by a conductivity detector, and the chromatographic data is acquired and analyzed in the host computer software.

7. The monitoring system for anions and cations in underground hot spring water according to claim 6, characterized in that: The front-stage pipeline of the sample cup is provided with a first-stage filter, and the filter element material of the first-stage filter is PP fiber membrane or PVDF fiber membrane.

8. The monitoring system for anions and cations in underground hot spring water according to claim 7, characterized in that: A second-stage filter is arranged between the sample cup and the sampling tank, and the filter element material of the second-stage filter is a PTFE membrane.

9. The monitoring system for anions and cations in underground hot spring water according to claim 8, characterized in that: There are at least two second-stage filters, which are connected in parallel in the pipeline.

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