PH measuring system used in harsh environment and measuring method thereof

Abstract

The invention provides a pH measuring system used in a harsh environment and a measuring method thereof, and the system comprises an electrode front end and an electrode rear end which are in threaded connection; the electrode front end comprises a temperature probe, an electrode front end shell, a sealing film, an electrode connecting plate, an electrode measuring bulb, a pH electrode accessory, an electrode reference bulb and electrode filling liquid, the sealing film is used for sealing the electrode filling liquid in the electrode front end shell, and the electrode measuring bulb and the electrode reference bulb are respectively used for measuring and calculating the outside and the filling liquid; the temperature probe is used for measuring the temperature; the electrode measuring bulb, the electrode reference bulb and the temperature probe are electrically connected with the electrode connecting plate respectively; the electrode rear end comprises a tail connecting plate, an electrode rear end shell, a waterproof connector, a signal processing module and a cable. The tail connecting plate is provided with a first spring piece, a second spring piece, a third spring piece and a fourth spring piece. According to the pH measurement system provided by the invention, the flow of replacing the pH electrode is simplified through split type design.

Description

Technical Field

[0001] The invention relates to the technical field of sensors, and in particular to a pH measurement system and a measurement method thereof for use in harsh environments. Background Art

[0002] pH testing plays an extremely important role in environmental science, industrial pharmaceuticals, food industry, medical diagnostics, agriculture and other fields, and is particularly critical in water quality monitoring. At present, with the rapid development of industrial manufacturing, water quality issues are attracting more and more attention. Water pollution seriously endangers human health. If the discharge of industrial wastewater is not monitored and controlled, it is likely to cause irreversible harm.

[0003] The pH measurement method uses a chemical reaction between the electrode and the liquid being measured to measure the acidity or alkalinity of the liquid. The principle of the pH electrode is to use the glass electrode method to detect the concentration of hydrogen ions in the solution. The principle of the glass electrode method is that the glass membrane will seep out or infiltrate when the pH is different. If the solution is alkaline, the hydrogen ions will seep out, and a negative charge will be formed outside the membrane, and vice versa. Since the electrolyte inside the glass electrode has a constant pH value, the potential on the surface of the membrane inside the measurement process remains constant. This results in different charges inside and outside the pH electrode.

[0004] It can be seen that pH measurement is an electrochemical process that consumes the electrolyte in the glass electrode. Therefore, most pH electrodes on the market are consumables. The life and service life of the electrode are determined by the electrolyte that can be stored inside the electrode.

[0005] In addition, the membrane internal resistance is an important parameter of the pH electrode, which is mainly related to the composition of the membrane material, the thickness of the membrane and the temperature, especially the current temperature value. The internal resistance of the glass electrode has a great influence on the stability of the pH test, which requires the pH meter to have a very high input impedance. When the internal resistance of the pH electrode is too large, the display of the instrument will drift, jitter, and become unstable, causing the electrode to polarize, seriously affecting the accuracy of the test.

[0006] When the pH electrode is in a harsh environment of high heat or high cold, the life of the pH electrode will be significantly reduced due to the rapid change of internal resistance. How to accurately determine the life of the electrode and when to replace the electrode becomes a problem. The replacement of the electrode is also very troublesome, wasting a lot of manpower costs and time.

[0007] Therefore, it is necessary to provide a pH measurement system and a measurement method thereof for use in harsh environments to effectively solve the above problems. Summary of the invention

[0008] The present invention provides a pH measurement system and a measurement method for use in harsh environments. Through a split design, the process of replacing a pH electrode is simplified, labor costs are reduced, and work efficiency is improved.

[0009] The embodiment of the present invention provides a pH measurement system for harsh environments, the system comprising an electrode front end and an electrode rear end, the electrode front end and the electrode rear end being connected by threads; the electrode front end comprises a temperature probe, an electrode front end housing, a sealing film, an electrode connecting plate, an electrode measuring bulb, a pH electrode accessory, an electrode reference bulb and an electrode filling liquid, the temperature probe, the sealing film, the electrode connecting plate, the electrode measuring bulb, the pH electrode accessory, the electrode reference bulb and the electrode filling liquid are arranged in the electrode front end housing, the sealing film is used to seal the electrode filling liquid inside the electrode front end housing, the electrode measuring bulb and the electrode reference bulb are respectively used to measure and calculate the outside world and the filling liquid, the temperature probe is used to measure the temperature, and the electrode measuring bulb, the electrode reference bulb and the temperature probe are respectively electrically connected to the electrode connecting plate;

[0010] The electrode rear end includes a tail connecting plate, an electrode rear end housing, a waterproof connector, a signal processing module and a cable. The tail connecting plate, the waterproof connector, the signal processing module and the cable are arranged in the electrode rear end housing. The tail connecting plate is provided with a first spring sheet, a second spring sheet, a third spring sheet and a fourth spring sheet, which correspond to a first signal ring, a second signal ring, a third signal ring and a fourth signal ring respectively.

[0011] Preferably, the system further comprises an electrode protection cap, which is sleeved on one side of the front end of the electrode, and the electrode protection cap is used to protect the temperature probe and the electrode measuring bulb.

[0012] Preferably, the electrode connecting plate is fixed to the front end housing of the electrode by clamping, the first signal ring, the second signal ring, the third signal ring and the fourth signal ring are fastened to the outer surface of the electrode connecting plate, and are connected to the measuring end of the pH electrode through a cable, the first signal ring is electrically connected to the first end of the temperature probe, the second signal ring is electrically connected to the electrode reference bulb, the third signal ring is electrically connected to the second end of the temperature probe, and the fourth signal ring is electrically connected to the electrode measuring bulb.

[0013] Preferably, the first spring piece, the second spring piece, the third spring piece and the fourth spring piece are elastic and can be pressed down by external force, and the movement trajectories of the first spring piece, the second spring piece, the third spring piece and the fourth spring piece during threaded installation are completely matched with the first signal ring, the second signal ring, the third signal ring and the fourth signal ring, respectively.

[0014] Preferably, after receiving the analog signal, the tail connecting board transmits it to the signal processing module for data processing and analysis.

[0015] Preferably, the signal processing module transmits the processed signal through the cable, and the cable is an RS-485 serial bus.

[0016] The embodiment of the present invention further provides a measurement method applicable to the pH measurement system used in the harsh environment, which calculates the resistance value of the membrane internal resistance of the electrode being measured by measuring the voltage difference before and after the external resistor is added to the electrode being measured, and is specifically calculated by the following formula:

[0017]

[0018] Among them, R e is the resistance value of the membrane internal resistance of the electrode being measured, E1 is the voltage value measured by the pH electrode when the external resistor is not added, E2 is the voltage value measured by the pH electrode when the external resistor is added, R s is the resistance value of the external resistor.

[0019] Preferably, the membrane internal resistance of the electrode to be measured is measured at preset intervals to determine whether the voltage value is stable, and if so, the voltage value is recorded; if not, the voltage value is not recorded;

[0020] The determination of whether the voltage value is stable is specifically performed in the following manner:

[0021] If the fluctuation value of the voltage value within the preset time is within the first threshold range, the voltage value is stable; if the fluctuation value of the voltage value within the preset time exceeds the first threshold, the voltage value is unstable.

[0022] Preferably, the membrane internal resistance is arranged between the electrode reference bulb and the electrode measurement bulb, and the external resistor is built into the signal processing module.

[0023] Preferably, a time-resistance curve is constructed based on the accumulated resistance value of the membrane internal resistance of the electrode being measured. According to the time-resistance curve, the slope obtained by derivation represents the changing trend of the resistance value of the membrane internal resistance of the electrode being measured, and the life of the electrode being measured is predicted based on the changing trend.

[0024] The technical solution of the embodiment of the present invention has the following beneficial effects:

[0025] The embodiment of the present invention provides a pH measurement system and a measurement method for harsh environments. The system includes an electrode front end and an electrode rear end, and the electrode front end and the electrode rear end are connected by a thread; the electrode front end includes a temperature probe, an electrode front end housing, a sealing film, an electrode connecting plate, an electrode measuring bulb, a pH electrode accessory, an electrode reference bulb and an electrode filling liquid, and the temperature probe, the sealing film, the electrode connecting plate, the electrode measuring bulb, the pH electrode accessory, the electrode reference bulb and the electrode filling liquid are arranged in the electrode front end housing, the sealing film is used to seal the electrode filling liquid inside the electrode front end housing, the electrode measuring bulb and the electrode reference bulb are used for measuring and calculating the outside world and the filling liquid respectively, and the temperature probe The head is used to measure the temperature, and the electrode measuring bulb, the electrode reference bulb, and the temperature probe are electrically connected to the electrode connecting plate respectively; the electrode rear end includes a tail connecting plate, an electrode rear end shell, a waterproof connector, a signal processing module, and a cable, and the tail connecting plate, the waterproof connector, the signal processing module, and the cable are arranged in the electrode rear end shell, and the tail connecting plate is provided with a first spring sheet, a second spring sheet, a third spring sheet, and a fourth spring sheet, which correspond to the first signal ring, the second signal ring, the third signal ring, and the fourth signal ring respectively. The split design solves the problem of repeated replacement of the pH electrode after the life of the electrode expires in a harsh environment, and the complicated process, simplifies the process of replacing the pH electrode, reduces the labor cost, and improves the work efficiency;

[0026] Furthermore, it provides the real-time measurement capability of the internal resistance of the pH membrane and the ability to predict the life span, which solves the problem that the life span of the pH electrode is difficult to predict and the replacement time cannot be determined due to complex conditions in harsh environments. It makes the process controllable and digitized, reducing the risk of using expired electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are some embodiments of the present invention, not all embodiments. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0028] Figure 1 A schematic diagram of the structure of a pH measurement system for use in harsh environments provided by one embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the structure of an electrode front end in a pH measurement system for use in a harsh environment provided by an embodiment of the present invention;

[0030] Figure 3A schematic diagram of the structure of an electrode connecting plate in a pH measurement system for use in a harsh environment provided by one embodiment of the present invention;

[0031] Figure 4 A schematic diagram of the structure of an electrode rear end in a pH measurement system for use in a harsh environment provided by one embodiment of the present invention;

[0032] Figure 5 A schematic diagram of the structure of a tail connection plate in a pH measurement system for use in a harsh environment provided by one embodiment of the present invention;

[0033] Figure 6 A schematic diagram of a circuit for measuring the internal resistance of an electrode membrane in a pH measurement system for use in a harsh environment is provided in accordance with an embodiment of the present invention.

[0034] Reference numerals:

[0035] 11. Front end of electrode; 12. Back end of electrode;

[0036] 21. Electrode protection cap; 22. Temperature probe; 23. Electrode front end housing; 24. Sealing film; 25. Electrode connection plate; 26. Electrode measurement bulb; 27. pH electrode accessories; 28. Electrode reference bulb; 29. ​​Electrode filling solution;

[0037] 31. First signal ring; 32. Second signal ring; 33. Third signal ring; 34. Fourth signal ring;

[0038] 41. Tail connection plate; 42. Electrode rear end housing; 43. Waterproof connector; 44. Signal processing module; 45. Cable;

[0039] 51. First spring piece; 52. Second spring piece; 53. Third spring piece; 54. Fourth spring piece. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0042] Based on the problems existing in the prior art, the embodiments of the present invention provide a pH measurement system and a measurement method thereof for use in harsh environments. Through a split design, the process of replacing the pH electrode is simplified, the labor cost is reduced, and the work efficiency is improved.

[0043] Figure 1 A schematic diagram of the structure of a pH measurement system for use in harsh environments provided by one embodiment of the present invention; Figure 2 A schematic diagram of the structure of an electrode front end in a pH measurement system for use in a harsh environment provided by an embodiment of the present invention; Figure 3 A schematic diagram of the structure of an electrode connecting plate in a pH measurement system for use in a harsh environment provided by one embodiment of the present invention; Figure 4 A schematic diagram of the structure of an electrode rear end in a pH measurement system for use in a harsh environment provided by one embodiment of the present invention; Figure 5 A schematic diagram of the structure of a tail connection plate in a pH measurement system for use in a harsh environment provided by one embodiment of the present invention; Figure 6 A schematic diagram of a circuit for measuring the internal resistance of an electrode membrane in a pH measurement system for use in harsh environments is provided in accordance with an embodiment of the present invention. Figure 1-Figure 6 The embodiment of the present invention provides a pH measurement system for harsh environments, the system comprising an electrode front end 11 and an electrode rear end 12, the electrode front end 11 and the electrode rear end 12 being connected by threads; the electrode front end 11 comprises a temperature probe, an electrode front end 11 housing, a sealing film 24, an electrode connecting plate 25, an electrode measuring bulb 26, a pH electrode accessory 27, an electrode reference bulb 28 and an electrode filling liquid 29, the temperature probe, the sealing film 24, the electrode connecting plate 25, the electrode measuring bulb 26, the pH electrode accessory 27, the electrode reference bulb 28 and the electrode filling liquid 29 are arranged in the electrode front end housing 23, the sealing film 24 is used to seal the electrode filling liquid 29 inside the electrode front end housing 23, the electrode measuring bulb 26 and the electrode reference bulb 28 are respectively used for measuring and calculating the outside world and the filling liquid, the temperature probe is used to measure the temperature, and the electrode measuring bulb 26, the electrode reference bulb 28 and the temperature probe are respectively electrically connected to the electrode connecting plate 25;

[0044] The electrode rear end 12 includes a tail connecting plate 41, an electrode rear end shell 42, a waterproof connector 43, a signal processing module 44 and a cable 45. The tail connecting plate 41, the waterproof connector 43, the signal processing module 44 and the cable 45 are arranged in the electrode rear end shell 42. The tail connecting plate 41 is provided with a first spring sheet 51, a second spring sheet 52, a third spring sheet 53 and a fourth spring sheet 54, which correspond to the first signal ring 31, the second signal ring 32, the third signal ring 33 and the fourth signal ring 34 respectively.

[0045] Among them, the mating parts of the electrode front end 11 and the electrode rear end 12 are sealed with the sealing thread through the sealing film 24, and the electrical signals are interacted with the first spring piece 51, the second spring piece 52, the third spring piece 53 and the fourth spring piece 54 through the metal first signal ring 31, the second signal ring 32, the third signal ring 33 and the fourth signal ring 34.

[0046] The electrode front end 11 is used to store measurement components related to the pH measurement system, store the electrode filling solution 29, and support electrochemical reactions related to pH measurement, including temperature-related measurements. The electrode rear end 12 is connected to the electrode front end 11 through a thread, and is used to store data processing and control modules related to the pH measurement system, as well as monitoring modules related to the life of the electrode front end 11, and transmit data to the outside through the cable 45, electrode analog signal processing and conversion, as well as real-time measurement of the electrode membrane internal resistance and big data analysis and life prediction.

[0047] A total of four wires, including the electrode measuring bulb 26 , the electrode reference bulb 28 and the temperature probe 22 , are connected to the electrode connecting plate 25 and transmit electrical signals to the electrode rear end 12 .

[0048] In a specific implementation, the system further includes an electrode protection cap 21 , which is sleeved on one side of the electrode front end 11 . The electrode protection cap 21 is used to protect the temperature probe 22 and the electrode measuring bulb 26 .

[0049] In a specific implementation, the electrode connecting plate 25 is fixed to the electrode front end housing 23 by clamping, the first signal ring 31, the second signal ring 32, the third signal ring 33 and the fourth signal ring 34 are fastened to the outer surface of the electrode connecting plate 25, and are connected to the pH electrode measuring end through a cable, the first signal ring 31 is electrically connected to the first end of the temperature probe 22, the second signal ring 32 is electrically connected to the electrode reference bulb 28, the third signal ring 33 is electrically connected to the second end of the temperature probe 22, and the fourth signal ring 34 is electrically connected to the electrode measuring bulb 26.

[0050] In a specific implementation, the first spring piece 51, the second spring piece 52, the third spring piece 53 and the fourth spring piece 54 are elastic and can be pressed down by an external force. The movement trajectories of the first spring piece, the second spring piece, the third spring piece and the fourth spring piece during threaded installation are completely matched with the first signal ring 31, the second signal ring 32, the third signal ring 33 and the fourth signal ring 34 respectively.

[0051] Figure 5 The four dotted tracks are the moving tracks of the spring sheets during threaded installation, which fully match the corresponding signal rings to ensure the normal path of the electrical signal.

[0052] In a specific implementation, after receiving the analog signal, the tail connecting board 41 transmits it to the signal processing module 44 for data processing and analysis.

[0053] In a specific implementation, the signal processing module 44 transmits the processed signal through the cable 45, and the cable 45 is an RS-485 serial bus.

[0054] Among them, there are four spring sheets on the tail connecting plate 41, namely, the first spring sheet 51, the second spring sheet 52, the third spring sheet 53 and the fourth spring sheet 54, corresponding to the four signal rings, the first signal ring 31, the second signal ring 32, the third signal ring 33 and the fourth signal ring 34. During the installation process, it is ensured that when the rotating thread tightens the electrode front end 11 and the electrode rear end 12, the electrical signal connection between the electrode front end 11 and the electrode rear end 12 can always be kept without interruption or error through the elasticity of the spring sheet.

[0055] The above system makes the pH electrode head replaceable. After the electrode filling liquid is used up or the life of the electrode is exhausted, the electrode front end 11 can be loosened by screwing, and the new electrode front end can be replaced and the old electrode rear end 12 can be used continuously.

[0056] The embodiment of the present invention further provides a measurement method applicable to the pH measurement system used in the harsh environment, which calculates the resistance value of the membrane internal resistance of the electrode being measured by measuring the voltage difference before and after the external resistor is added to the electrode being measured, and is specifically calculated by the following formula:

[0057]

[0058] Among them, R e is the resistance value of the membrane internal resistance of the electrode being measured, E1 is the voltage value measured by the pH electrode when the external resistor is not added, E2 is the voltage value measured by the pH electrode when the external resistor is added, R s is the resistance value of the external resistor.

[0059] The unit of the resistance value of the membrane internal resistance and the resistance value of the external resistor is megohm, and the unit of the voltage value is millivolt.

[0060] In a specific implementation, the membrane internal resistance of the electrode to be measured is measured at a preset time interval to determine whether the voltage value is stable, and if so, the voltage value is recorded; if not, the voltage value is not recorded;

[0061] The determination of whether the voltage value is stable is specifically performed in the following manner:

[0062] If the fluctuation value of the voltage value within the preset time is within the first threshold range, the voltage value is stable; if the fluctuation value of the voltage value within the preset time exceeds the first threshold, the voltage value is unstable.

[0063] The preset time may be assumed to be 30 seconds, and the first threshold may be assumed to be 5%. If the measured voltage value is unstable, it indicates that the external environmental conditions do not meet the requirements, and the operation of measuring the internal resistance of the electrode film is terminated.

[0064] In a specific implementation, the membrane internal resistance is arranged between the electrode reference bulb 28 and the electrode measurement bulb 26 , and the external resistor is built into the signal processing module 44 .

[0065] In a specific implementation, a time-resistance curve is constructed based on the accumulated resistance value of the membrane internal resistance of the electrode under test. The slope obtained by derivation of the time-resistance curve represents the changing trend of the resistance value of the membrane internal resistance of the electrode under test, and the life of the electrode under test is predicted based on the changing trend.

[0066] In summary, the embodiment of the present invention provides a pH measurement system and a measurement method for harsh environments. The system includes an electrode front end and an electrode rear end, and the electrode front end and the electrode rear end are connected by a thread; the electrode front end includes a temperature probe, an electrode front end housing, a sealing film, an electrode connecting plate, an electrode measuring bulb, a pH electrode accessory, an electrode reference bulb and an electrode filling liquid, and the temperature probe, the sealing film, the electrode connecting plate, the electrode measuring bulb, the pH electrode accessory, the electrode reference bulb, and the electrode filling liquid are arranged in the electrode front end housing, and the sealing film is used to seal the electrode filling liquid inside the electrode front end housing, the electrode measuring bulb and the electrode reference bulb are used for measuring and calculating the outside world and the filling liquid respectively, and the temperature probe, the sealing film, the electrode connecting plate, the electrode measuring bulb, the pH electrode accessory, the electrode reference bulb, and the electrode filling liquid are arranged in the electrode front end housing, and the sealing film is used to seal the electrode filling liquid inside the electrode front end housing, and the electrode measuring bulb and the electrode reference bulb are used for measuring and calculating the outside world and the filling liquid respectively. The temperature probe is used to measure the temperature. The electrode measuring bulb, the electrode reference bulb and the temperature probe are electrically connected to the electrode connecting plate respectively. The electrode rear end includes a tail connecting plate, an electrode rear end housing, a waterproof connector, a signal processing module and a cable. The tail connecting plate, the waterproof connector, the signal processing module and the cable are arranged in the electrode rear end housing. The tail connecting plate is provided with a first spring sheet, a second spring sheet, a third spring sheet and a fourth spring sheet, which correspond to the first signal ring, the second signal ring, the third signal ring and the fourth signal ring respectively. The split design solves the problem of repeated replacement of the pH electrode after the life of the electrode expires in a harsh environment and the complicated process, simplifies the process of replacing the pH electrode, reduces the labor cost and improves the work efficiency.

[0067] Furthermore, it provides the real-time measurement capability of the internal resistance of the pH membrane and the ability to predict the life span, which solves the problem that the life span of the pH electrode is difficult to predict and the replacement time cannot be determined due to complex conditions in harsh environments. It makes the process controllable and digitized, reducing the risk of using expired electrodes.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pH measurement system for use in harsh environments, characterized in that: The system comprises an electrode front end and an electrode rear end, wherein the electrode front end and the electrode rear end are connected by threads; the electrode front end comprises a temperature probe, an electrode front end housing, a sealing film, an electrode connecting plate, an electrode measuring bulb, a pH electrode accessory, an electrode reference bulb and an electrode filling liquid, wherein the temperature probe, the sealing film, the electrode connecting plate, the electrode measuring bulb, the pH electrode accessory, the electrode reference bulb and the electrode filling liquid are arranged in the electrode front end housing, wherein the sealing film is used to seal the electrode filling liquid inside the electrode front end housing, wherein the electrode measuring bulb and the electrode reference bulb are used to measure and calculate the outside world and the filling liquid respectively, wherein the temperature probe is used to measure the temperature, and wherein the electrode measuring bulb, the electrode reference bulb and the temperature probe are electrically connected to the electrode connecting plate respectively; The electrode rear end includes a tail connecting plate, an electrode rear end housing, a waterproof connector, a signal processing module and a cable. The tail connecting plate, the waterproof connector, the signal processing module and the cable are arranged in the electrode rear end housing. The tail connecting plate is provided with a first spring sheet, a second spring sheet, a third spring sheet and a fourth spring sheet, which correspond to a first signal ring, a second signal ring, a third signal ring and a fourth signal ring respectively.

2. The pH measurement system for harsh environments according to claim 1, characterized in that: The system also includes an electrode protection cap, which is sleeved on one side of the front end of the electrode, and the electrode protection cap is used to protect the temperature probe and the electrode measuring bulb.

3. The pH measurement system for harsh environments according to claim 1, characterized in that: The electrode connecting plate is fixed to the front end housing of the electrode by clamping, and the first signal ring, the second signal ring, the third signal ring and the fourth signal ring are fastened to the outer side of the electrode connecting plate and are connected to the measuring end of the pH electrode through a cable. The first signal ring is electrically connected to the first end of the temperature probe, the second signal ring is electrically connected to the electrode reference bulb, the third signal ring is electrically connected to the second end of the temperature probe, and the fourth signal ring is electrically connected to the electrode measuring bulb.

4. The pH measurement system for harsh environments according to claim 1, characterized in that: The first spring piece, the second spring piece, the third spring piece and the fourth spring piece are elastic and can be pressed down by external force. The movement trajectories of the first spring piece, the second spring piece, the third spring piece and the fourth spring piece during threaded installation are completely matched with the first signal ring, the second signal ring, the third signal ring and the fourth signal ring respectively.

5. The pH measurement system for harsh environments according to claim 1, characterized in that: After receiving the analog signal, the tail connecting board transmits it to the signal processing module for data processing and analysis.

6. The pH measurement system for harsh environments according to claim 5, characterized in that: The signal processing module transmits the processed signal through the cable, and the cable is an RS-485 serial bus.

7. A measurement method applicable to the pH measurement system for harsh environments as claimed in claim 1, characterized in that: The resistance value of the membrane internal resistance of the electrode being tested is calculated by measuring the voltage difference before and after the external resistor is added to the electrode being tested. The specific calculation is performed using the following formula: Among them, R e is the resistance value of the membrane internal resistance of the electrode being measured, E1 is the voltage value measured by the pH electrode when the external resistor is not added, E2 is the voltage value measured by the pH electrode when the external resistor is added, R s is the resistance value of the external resistor.

8. The measuring method according to claim 7, characterized in that: Measuring the membrane internal resistance of the electrode under test at preset intervals to determine whether the voltage value is stable, recording the voltage value if it is stable, and giving up recording the voltage value if it is unstable; The determination of whether the voltage value is stable is specifically performed in the following manner: If the fluctuation value of the voltage value within the preset time is within the first threshold range, the voltage value is stable; if the fluctuation value of the voltage value within the preset time exceeds the first threshold, the voltage value is unstable.

9. The measuring method according to claim 7, characterized in that: The membrane internal resistance is arranged between the electrode reference bulb and the electrode measurement bulb, and the external resistor is built in the signal processing module.

10. The measuring method according to claim 7, characterized in that: A time-resistance curve is constructed based on the accumulated resistance value of the membrane internal resistance of the electrode under test. The slope obtained by derivation of the time-resistance curve represents the change trend of the resistance value of the membrane internal resistance of the electrode under test, and the life of the electrode under test is predicted based on the change trend.

Images