Polarity and electrical property analysis equipment capable of adjusting dissociation state for organic matters in water

Abstract

The utility model discloses polarity and electrical property analysis equipment for organic matters in water capable of adjusting a dissociation state. The polarity and electrical property analysis equipment comprises a shell, a mixing container; the detection unit is connected to the mixing container and comprises a background channel, a first channel for intercepting non-polar organic matters, a second channel for intercepting strong electropositive organic matters, a third channel for intercepting weak electropositive organic matters and a detector for detecting the concentration of the organic matters; the cleaning, activating and sampling unit is connected to the mixing container and is used for introducing acid liquor and pure water into the mixing container to clean the mixing container, introducing pure water into the mixing container to activate the detection unit and introducing a sample to be detected into the mixing container; the extraction unit is connected to the mixing container and is used for carrying out acid regulation or alkali regulation on the to-be-detected sample in the mixing container; and the waste discharge unit is connected to the mixing container and is used for discharging the waste liquid in the mixing container. The equipment provided by the utility model is simple in structure and convenient to detect.

Description

Technical Field

[0001] The utility model relates to the technical field of analysis and detection, in particular to a polarity and electrical analysis device for organic matter in water capable of adjusting the dissociation state. Background Art

[0002] The safety of drinking water quality is related to human health and social stability. Organic matter is an important source of precursors of disinfection by-products. With climate change and industrial activities, the properties of organic matter in drinking water sources are becoming more complex and the concentration is increasing, which brings challenges to the control of drinking water disinfection by-products. Therefore, only by analyzing the properties of organic matter can we understand the migration and transformation laws of organic matter with different characteristics during drinking water treatment and disinfection, which is of great significance to the safety of drinking water quality.

[0003] Polarity and electrical properties are important characteristics of organic matter. The polarity of organic matter essentially comes from the unevenness of the net charge distribution. The greater the unevenness, the stronger the polarity. For example, when a molecule has very obvious alternating positive and negative atomic charges, it is considered to have a highly polar characteristic. Theoretical calculations can measure polarity through dipole moment, electrostatic potential, and other methods. The dipole moment essentially reflects the separation of the positive charge center and the negative charge center of the system, but due to the influence of the configuration, the overall dipole moment of the macromolecule may be offset by the local dipole moment. The electrostatic potential is directly determined by the charge distribution of the system. The electrostatic potential is of great significance for studying intermolecular electrostatic interactions and predicting the properties of molecular condensed phases. The uneven distribution of charge in the molecule will be reflected in the electrostatic potential distribution on the molecular surface. Therefore, by characterizing the characteristics of the electrostatic potential distribution on the molecular surface, the polarity of the molecule can be measured.

[0004] The electrical properties of organic matter refer to the charge on the surface of organic molecules. Taking amino acids, which are common natural organic matter in water sources, as an example, because of their amphoteric ionization characteristics, the pKa of the carboxyl group is around 2, while the pKa of the amine group is usually around 10. Among the 20 common amino acids, only histidine, lysine and arginine have isoelectric points greater than 7, while 17 common amino acids such as aspartic acid and glutamic acid are all negatively charged under neutral conditions.

[0005] The applicant's research found that the non-polar and positively charged properties of organic matter are related to the removal rate of organic matter in the water purification process in the drinking water treatment plant and the generation of disinfection by-products during the disinfection process. At present, the analysis of the characteristics of organic matter is mainly focused on scales such as hydrophobicity and molecular weight, and less attention is paid to polarity and electrical characteristics. However, the analytical methods from the perspective of hydrophobicity and molecular weight are expensive and time-consuming, and the results are mainly qualitative descriptions, which are difficult to quantify. Therefore, separating organic matter according to different polarities and electrical properties and characterizing it with the total amount of organic matter will help understand the properties of organic matter and the laws of migration and transformation in the drinking water treatment process.

[0006] Typically, analyzing organic matter in water requires a complex pretreatment process, which includes adjusting the pH of the sample to change the dissociation state of the organic matter, and then using different solid phase extraction techniques for separation. However, traditional equipment often has deficiencies in terms of flexibility in pH adjustment, processing speed, degree of automation, and separation efficiency. These limitations may lead to reduced accuracy and repeatability of the analysis, increasing the complexity and time cost of the operation.

[0007] In order to solve the above problems, the present utility model is provided. Utility Model Content

[0008] The utility model aims to provide a polarity and electrical analysis device for organic matter in water with adjustable dissociation state, which can realize the determination and analysis of polarity and electrical properties of organic matter in water samples with different dissociation states.

[0009] Based on the above problems, the technical solution provided by the utility model is:

[0010] A polarity and electrical analysis device for organic matter in water capable of adjusting the dissociation state, comprising:

[0011] shell;

[0012] a mixing container mounted on the housing;

[0013] A detection unit, which is mounted on the housing and connected to the mixing container, comprises a background channel, a first channel for intercepting non-polar organic matter, a second channel for intercepting strongly positively charged organic matter, a third channel for intercepting weakly positively charged organic matter, and a detector for detecting the concentration of organic matter;

[0014] A cleaning and activation sampling unit, which is connected to the mixing container and is used to pass acid solution and pure water into the mixing container to clean the mixing container, pass pure water into the mixing container to activate the detection unit, and pass a sample to be tested into the mixing container;

[0015] an extraction unit connected to the mixing container and used to perform acid adjustment or alkali adjustment on the sample to be tested in the mixing container;

[0016] A waste discharge unit is connected to the mixing container and is used to discharge the waste liquid in the mixing container.

[0017] In some embodiments, the number of the first channel, the second channel, and the third channel are three respectively, the first channel is loaded with an adsorption column for retaining non-polar organic matter, the second channel is loaded with an adsorption column for retaining strong electrical organic matter, and the third channel is loaded with an adsorption column for retaining weak electrical organic matter.

[0018] In some embodiments, the detection unit also includes a sample injection pump, a multi-channel selection control valve and a detection selection control valve, the inlet end of the sample injection pump is connected to the mixing container and the outlet end is connected to the multi-channel selection control valve, the two ends of the background channel, the first channel, the second channel and the third channel are respectively connected to the multi-channel selection control valve and the detection selection control valve, and the detection selection control valve is connected to the detector.

[0019] In some of the embodiments, the cleaning and activation sampling unit includes a sample container, an acid liquid container, and a pure water container arranged outside the shell, and an injection selection control valve and a peristaltic pump installed on the shell, the sample container, the acid liquid container, and the pure water container are respectively connected to the injection selection control valve via pipelines, and the injection selection control valve is connected to the mixing container via the peristaltic pump.

[0020] In some of the embodiments, a filter is further provided between the sample container and the injection selection control valve.

[0021] In some of the embodiments, the extraction unit includes an alkaline solution container, an acid solution container, and a pure water container arranged outside the shell, and an extraction selection control valve and an extraction injection pump installed on the shell, the alkaline solution container, the acid solution container, and the pure water container are respectively connected to the extraction selection control valve via pipelines, and the extraction selection control valve is connected to the mixing container via the extraction injection pump.

[0022] In some embodiments, the waste discharge unit includes a waste liquid container connected to the mixing container via a first waste discharge pipe and a waste discharge solenoid valve arranged on the first waste discharge pipe, an overflow pipe is connected between the mixing container and the waste liquid container, the waste liquid container is arranged outside the outer shell, and the waste discharge solenoid valve is installed on the outer shell.

[0023] In some of the embodiments, the mixing container is further connected to an aeration component disposed inside the shell.

[0024] In some embodiments, the detector is connected to the waste liquid container via a second waste pipe.

[0025] Compared with the prior art, the advantages of the utility model are:

[0026] 1. The equipment can measure the concentration of non-polar, strongly positively charged and weakly positively charged organic matter in the original state of the water sample, as well as the concentration of non-polar, strongly positively charged and weakly positively charged organic matter in protonated and non-protonated organic matter; in typical water purification processes such as coagulation, adsorption and oxidation, the removal capacity of organic matter with different characteristics is different. Therefore, by analyzing the concentration of the above-mentioned types of organic matter and the proportion of them in the total organic matter, the potential of each process for organic matter removal can be mastered, so as to adjust the process parameters accordingly and improve the water purification efficiency; when the proportion of positively charged organic matter is low, the removal rate of organic matter by the coagulation process can be increased by increasing the dosage of coagulant; when the proportion of non-polar organic matter is high, the removal of organic matter by the activated carbon process can be enhanced by reducing the filtration rate of the activated carbon unit and increasing the adsorption residence time;

[0027] 2. The equipment has a simple structure and can be operated automatically by simply placing the sample in a sample bottle. Compared with the organic matter analysis method under laboratory conditions, this method can be applied on-site and can provide timely analysis results and targeted process adjustment strategies based on the dynamic change characteristics of organic matter in water. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. The drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 This is a schematic structural diagram of an embodiment of a device for analyzing polarity and electrical properties of organic matter in water with adjustable dissociation state according to the utility model;

[0030] Figure 2 This is a schematic diagram of the pipeline connection of an embodiment of the utility model;

[0031] in:

[0032] 1. Shell; 2. Sample container; 3. Acid container; 4. Alkali container; 5. Pure water container; 6. Filter; 7. Injection selection control valve; 8. Peristaltic pump; 9. Extraction selection control valve; 10. Extraction injection pump; 11. Mixing container; 12. Sample injection pump; 13. Multi-channel selection control valve; 14. Background channel; 15. First channel; 16. Second channel; 17. Third channel; 18. Detection selection control valve; 19. Detector; 20. Waste liquid container; 21. Waste discharge solenoid valve; 22. Aeration component; 23. First waste pipe; 24. Second waste pipe; 25. Overflow pipe. DETAILED DESCRIPTION

[0033] The above scheme is further described below in conjunction with specific examples. It should be understood that these examples are used to illustrate the utility model and are not limited to the scope of the utility model. The implementation conditions used in the examples can be further adjusted according to the conditions of the specific manufacturer, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0034] like Figure 1 and Figure 2 As shown, it is a structural schematic diagram of an embodiment of the utility model, which provides a polarity and electrical analysis device for organic matter in water with adjustable dissociation state, including a shell 1, a mixing container 11, a detection unit, a cleaning activation sampling unit, an extraction unit and a waste discharge unit, wherein the mixing container 11 is installed on the shell 1.

[0035] The detection unit is installed on the housing 1 and connected to the mixing container 11, and includes a background channel 14, a first channel 15 for intercepting non-polar organic matter, a second channel 16 for intercepting strongly positively charged organic matter, a third channel 17 for intercepting weakly positively charged organic matter, and a detector 19 for detecting the concentration of organic matter. After the organic matter of the sample to be tested in the mixing container 11 is intercepted by the first channel 15, the second channel 16, and the third channel 17, the value is compared with the measured value of the background channel 14 to measure the concentration of non-polar organic matter, strongly positively charged organic matter, and weakly positively charged organic matter in the sample to be tested.

[0036] In this example, the number of the first channel 15, the second channel 16, and the third channel 17 are three respectively. The first channel 15 is loaded with an adsorption column for adsorbing non-polar organic matter, such as a C-18 column, the second channel 16 is loaded with an adsorption column for adsorbing strong electric organic matter, such as an SCX column, and the third channel 17 is loaded with an adsorption column for adsorbing weak electric organic matter, such as a PRS column.

[0037] In order to realize sampling in each channel, the detection unit also includes a sample injection pump 12, a multi-channel selection control valve 13 and a detection selection control valve 18. The inlet end of the sample injection pump 12 is connected to the mixing container 11 and the outlet end is connected to the multi-channel selection control valve 13. The two ends of the background channel 14, the first channel 15, the second channel 16, and the third channel 17 are respectively connected to the multi-channel selection control valve 13 and the detection selection control valve 18. The detection selection control valve 18 is connected to the detector 19. The sample to be tested can be introduced into each channel through the multi-channel selection control valve 13 and the detection selection control valve 18, and then the detection of organic matter is completed through the detector 19. The detector 19 can use an ultraviolet-visible spectrophotometer.

[0038] The cleaning and activation sampling unit is connected to the mixing container 11, and is used to pass acid solution and pure water into the mixing container 11 to clean the mixing container 11, pass pure water into the mixing container 11 to activate the detection unit, and pass the sample to be tested into the mixing container 11. The cleaning and activation sampling unit includes a sample container 2, an acid container 3, and a pure water container 5 arranged outside the shell 1, and a sampling selection control valve 7 and a peristaltic pump 8 installed on the shell 1. The sample container 2, the acid container 3, and the pure water container 5 are respectively connected to the sampling selection control valve 7 through pipelines, and the sampling selection control valve 7 is connected to the mixing container 11 through the peristaltic pump 8. The acid solution and pure water are selectively passed into the mixing container 11 through the sampling selection control valve 7 to clean the mixing container 11, or the detection unit is activated by pure water, or the sample to be tested is passed into the mixing container 11.

[0039] In order to filter impurities in the sample to be tested, a filter 6 is provided between the sample container 2 and the sample injection selection control valve 7 .

[0040] An extraction unit is connected to a mixing container 11 and is used to perform acid or alkali adjustment on a sample to be tested in the mixing container 11. The extraction unit comprises an alkali liquid container 4, an acid liquid container 3, and a pure water container 5 arranged outside the outer shell 1, and an extraction selection control valve 9 and an extraction injection pump 10 installed on the outer shell 1. The alkali liquid container 4, the acid liquid container 3, and the pure water container 5 are respectively connected to the extraction selection control valve 9 via pipelines. The extraction selection control valve 9 is connected to the mixing container 11 via the extraction injection pump 10. The acid liquid and the alkali liquid are selectively introduced into the mixing container 11 through the extraction selection control valve 9 to acidify or alkalize the sample to be tested, or the extraction selection control valve 9 and the extraction injection pump 10 are cleaned with pure water.

[0041] A waste discharge unit is connected to the mixing container 11 and is used to discharge waste water in the mixing container 11, including a waste liquid container 20 connected to the mixing container 11 via a first waste discharge pipe 23 and a waste discharge solenoid valve 21 arranged on the first waste discharge pipe 23, and the waste liquid in the mixing container 11 is discharged into the waste liquid container 20 by opening the waste discharge solenoid valve 21, wherein the waste liquid container 20 is arranged outside the outer shell 1, and the waste discharge solenoid valve 21 is installed on the outer shell 1.

[0042] In order to purge the mixing container 11 during waste discharge, the mixing container 11 is also connected to an aeration component 22 disposed inside the housing 1 .

[0043] When the liquid in the mixing container 11 exceeds the volume of the mixing container 11 , an overflow pipe 25 is connected between the mixing container 11 and the waste liquid container 20 to facilitate the discharge of the excess liquid.

[0044] In order to facilitate the collection of waste liquid after detection by the detector 19 , the detector 19 is connected to the waste liquid container 20 via a second row of waste pipes 24 .

[0045] The working principle of the utility model is:

[0046] Cleaning of mixing vessels:

[0047] For acid cleaning, the injection selection control valve 7 is switched to the channel connected to the acid container 3, the peristaltic pump 8 is started, and it runs at a rate of 5 mL / min for 1 min, 5 ml of acid adjustment liquid is sucked into the mixing container 11, and the mixing container 11 is rinsed with acid, then the waste solenoid valve 21 is opened, the aeration component 22 is started, and the rinsing liquid is discharged into the waste liquid container 20. For pure water cleaning, the injection selection control valve 7 is switched to the channel connected to the pure water container 5, and it runs at a rate of 20 mL / min for 2 min, 40 mL of pure water is sucked into the mixing container 11, and the mixing container 11 is rinsed with pure water, then the waste solenoid valve 21 is opened, the aeration component 22 is started, and the rinsing liquid is discharged into the waste liquid container 20.

[0048] Adsorption column activation:

[0049] Switch the injection selection control valve 7 to the pipeline connected to the pure water container 5, run at a rate of 10 mL / min for 5 minutes, draw 50 ml of sample into the mixing container 11, and when activating the first channel 15 No. 1, switch the multi-channel selection control valve 13 and the detection selection control valve 18 to connect to the first channel 15 No. 1, run the sample injection pump at 5 mL / min for 1 minute, draw 5 mL of pure water and inject it into the first channel 15 No. 1, and discharge it into the waste liquid container 20 after passing through the detector 19. At this time, the detector 19 does not need to record the detection data. Repeat the above steps to complete the activation of all the first channels 15, the second channels 16, and the third channels 17.

[0050] Sample test:

[0051] Background concentration test: switch the injection selection control valve 7 to the channel connected to the sample container 2, run at a rate of 10mL / min for 4min, draw 40ml of sample into the mixing container 11, switch the multi-channel selection control valve 13 and the detection selection control valve 18 to the background channel 14, run the sample injection pump 12 at 10mL / min for 4min, draw 40mL of sample and inject it into the background channel 14, the sample enters the detector 19 through the background channel 14, the detector 19 records real-time data, and the sample at the outlet of the detector 19 is discharged into the waste liquid container 20. The test result at this time is the background value C0 of the organic matter in the sample. The background value of the same sample only needs to be tested once.

[0052] Non-polar organic matter test: switch the injection selection control valve 7 to the channel connected to the sample container 2, run at a rate of 10 mL / min for 4 minutes, draw 40 ml of sample into the mixing container 11, switch the multi-channel selection control valve 13 and the detection selection control valve 18 to connect to the first channel 15, and run the sample injection pump 12 at 10 mL / min for 4 minutes, draw 40 mL of sample and inject it into the first channel 15, the non-polar organic matter is adsorbed by the C-18 column in the first channel 15, and the sample then enters the detector 19, and the sample at the outlet of the detector 19 is discharged into the waste liquid container 20. The detector 19 records the real-time data that the concentration of organic matter not retained by the first channel 15 is C1, and the concentration of organic matter C 非极性 =C0-C1.

[0053] Protonated non-polar organic matter test: switch the injection selection control valve 7 to the channel connected to the sample container 2, run at a rate of 10 mL / min for 4 minutes, draw 40 ml of sample into the mixing container 11, switch the extraction selection control valve 9 to the acid container 3, and the extraction injection pump 10 draws 2 ml of acid and injects it into the mixing container 11 to complete the acidification of the sample. The multi-channel selection control valve 13 and the detection selection control valve 18 are switched to the first channel 15 No. 2, and the sample injection pump 12 runs at 10 mL / min for 4 minutes, draws 40 mL of sample and injects it into the first channel 15 No. 2. The non-polar organic matter in the protonated analysis state is adsorbed by the C-18 column in the first channel 15 No. 2, and the sample then enters the detector 19. The sample at the outlet of the detector 19 is discharged into the waste liquid container 20. The detector 19 records real-time data that the concentration of organic matter not retained by the first channel No. 2 is C2, so the concentration of organic matter C 质子化 / 非极性 =C0-C2.

[0054] Deprotonated non-polar organic matter test: the extraction selection control valve 9 is switched to be connected to the pure water container 5, the extraction injection pump 10 draws pure water to clean the residual acid in the extraction injection pump 10, the injection selection control valve 7 is switched to be connected to the channel of the sample container 2, and runs at a rate of 10 mL / min for 4 minutes, and 40 ml of sample is drawn into the mixing container 11, the extraction selection control valve 9 is switched to be connected to the alkali solution container 4, the extraction injection pump 10 draws 2 ml of alkali solution and injects it into the mixing container 11 to complete the alkalization of the sample, the multi-channel selection control valve 13 and the detection selection control valve 18 are switched to be connected to the first channel 15 No. 3, the loading injection pump 12 runs at 10 mL / min for 4 minutes, draws 40 mL of sample and injects it into the first channel 15 No. 3, the non-polar organic matter in the deprotonated analytical state is adsorbed by the C-18 column in the first channel 15 No. 3, and the sample then enters the detector 19, and the detector 19 records the real-time data that the concentration of organic matter not retained by the first channel 15 No. 3 is C3, then the concentration of organic matter C 去质子化 / 非极性 =C0-C3.

[0055] The test methods of channels 4 to 6 and 7 to 9 are the same as those of channels 1 to 3. The test results of channels 4 to 6 loaded with SCX columns are C 强正电性 =(C0-C4), C 质子化 / 强正电性 =(C0-C5), C 去质子化 / 强正电性 =(C0-C6); The channel test results of No. 7 to 9 loaded PRS columns are: C 弱正电性 =(C0-C7), C 质子化 / 弱正电性 =(C0-C8), C 去质子化 / 弱正电性 =(C0-C9).

[0056] In summary, the equipment has a simple structure and is easy to operate. It can determine the concentrations of non-polar, strongly positively charged and weakly positively charged organic matter in the original state of the water sample, as well as the concentrations of non-polar, strongly positively charged and weakly positively charged organic matter in protonated and non-protonated organic matter, providing a theoretical reference for the selection of water purification technology and improving water purification efficiency.

[0057] The above examples are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A polarity and electrical analysis device for organic matter in water capable of adjusting the dissociation state, characterized in that: include: shell; a mixing container mounted on the housing; A detection unit, which is mounted on the housing and connected to the mixing container, comprises a background channel, a first channel for intercepting non-polar organic matter, a second channel for intercepting strongly positively charged organic matter, a third channel for intercepting weakly positively charged organic matter, and a detector for detecting the concentration of organic matter; A cleaning and activation sampling unit, which is connected to the mixing container and is used to pass acid solution and pure water into the mixing container to clean the mixing container, pass pure water into the mixing container to activate the detection unit, and pass a sample to be tested into the mixing container; an extraction unit connected to the mixing container and used to perform acid adjustment or alkali adjustment on the sample to be tested in the mixing container; A waste discharge unit is connected to the mixing container and is used to discharge the waste liquid in the mixing container.

2. The polarity and electrical analysis device for organic matter in water with adjustable dissociation state according to claim 1 is characterized by: The number of the first channel, the second channel and the third channel are three respectively. The first channel is loaded with an adsorption column for intercepting non-polar organic matter, the second channel is loaded with an adsorption column for intercepting strong electric organic matter, and the third channel is loaded with an adsorption column for intercepting weak electric organic matter.

3. The polarity and electrical analysis device for organic matter in water with adjustable dissociation state according to claim 2 is characterized by: The detection unit also includes a sample injection pump, a multi-channel selection control valve and a detection selection control valve. The inlet end of the sample injection pump is connected to the mixing container and the outlet end is connected to the multi-channel selection control valve. The two ends of the background channel, the first channel, the second channel and the third channel are respectively connected to the multi-channel selection control valve and the detection selection control valve. The detection selection control valve is connected to the detector.

4. The polarity and electrical analysis device for organic matter in water with adjustable dissociation state according to claim 1 is characterized by: The cleaning and activation sampling unit includes a sample container, an acid container, and a pure water container arranged outside the shell, and a sampling selection control valve and a peristaltic pump installed on the shell. The sample container, the acid container, and the pure water container are respectively connected to the sampling selection control valve via pipelines, and the sampling selection control valve is connected to the mixing container via the peristaltic pump.

5. The polarity and electrical analysis device for organic matter in water with adjustable dissociation state according to claim 4 is characterized by: A filter is also provided between the sample container and the injection selection control valve.

6. The polarity and electrical analysis device for organic matter in water with adjustable dissociation state according to claim 4 is characterized by: The extraction unit includes an alkaline solution container, an acid solution container, and a pure water container arranged outside the shell, and an extraction selection control valve and an extraction injection pump installed on the shell. The alkaline solution container, the acid solution container, and the pure water container are respectively connected to the extraction selection control valve via pipelines, and the extraction selection control valve is connected to the mixing container via the extraction injection pump.

7. The polarity and electrical properties analysis device for organic matter in water with adjustable dissociation state according to claim 1, characterized in that: The waste discharge unit includes a waste liquid container connected to the mixing container via a first waste discharge pipe and a waste discharge solenoid valve arranged on the first waste discharge pipe. An overflow pipe is connected between the mixing container and the waste liquid container. The waste liquid container is arranged outside the shell, and the waste discharge solenoid valve is installed on the shell.

8. The polarity and electrical analysis device for organic matter in water with adjustable dissociation state according to claim 7, characterized in that: The mixing container is also connected to an aeration component arranged inside the shell.

9. The polarity and electrical properties analysis device for organic matter in water with adjustable dissociation state according to claim 7, characterized in that: The detector is connected to the waste liquid container via a second row of waste pipes.

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